WorldWideScience

Sample records for quasi-elastic rho0 electroproduction

  1. Exclusive rho^0 electroproduction on the proton at CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Morrow, Steven; Guidal, Michel; Garcon, Michel; Laget, Jean; Smith, Elton; Adams, Gary; Adhikari, Krishna; Aghasyan, Mher; Amaryan, Moscov; Amaryan, Moskov; Anghinolfi, Marco; Asryan, G.; Audit, Gerard; Avagyan, Harutyun; Bagdasaryan, H.; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Baltzell, Nathan; Barrow, Steve; Battaglieri, Marco; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bonner, Billy; Bookwalter, Craig; Bouchigny, Sylvain; Boyarinov, Sergey; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Bultmann, S.; Bueltmann, Stephen; Burkert, Volker; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Carnahan, Bryan; Casey, Liam; Cazes, Antoine; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Cords, Dieter; Corvisiero, Pietro; Crabb, Donald; Crannell, Hall; Crede, Volker; Cummings, John; Dale, Daniel; Dashyan, Natalya; De Masi, Rita; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Denizli, Haluk; Dennis, Lawrence; Deur, Alexandre; Dhamija, Seema; Dharmawardane, Kahanawita; Dhuga, Kalvir; Dickson, Richard; Didelez, Jean-Pierre; Djalali, Chaden; Dodge, Gail; Doughty, David; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fatemi, Renee; Fedotov, Gleb; Fersch, Robert; Feuerbach, Robert; Forest, Tony; Fradi, Ahmed; Gavalian, Gagik; Gevorgyan, Nerses; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gohn, Wesley; Gordon, Christopher; Gothe, Ralf; Graham, Lewis; Griffioen, Keith; Guillo, Matthieu; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hadjidakis, Cynthia; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Hardie, John; Hassall, Neil; Heddle, David; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hourany, E.; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Keller, Dustin; Kellie, James; Khandaker, Mahbubul; Khetarpal, Puneet; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Klimenko, Alexei; Kossov, Mikhail; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Kuznetsov, Viacheslav; Lachniet, Jeff; Langheinrich, Jorn; Lawrence, Dave; Li, Ji; Livingston, Kenneth; Lu, Haiyun; MacCormick, Marion; Marchand, Claude; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McCracken, Michael; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mehrabyan, Surik; Melone, Joseph; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Morand, Ludyvine; Moreno, Brahim; Moriya, Kei; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Nasseripour, Rakhsha; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; O' Rielly, Grant; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kijun; Park, Sungkyun; Pasyuk, Evgueni; Paterson, Craig; Pereira, S.Anefalos; Philips, Sasha; Pierce, Joshua; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Polli, Ermanno; Popa, Iulian; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Procureur, Sebastien; Prok, Yelena; Protopopescu, Dan; Qin, Liming; Raue, Brian; Riccardi, Gregory; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Rubin, Philip; Sabatie, Franck; Saini, Mukesh; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schott, Diane; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shvedunov, Nikolay; Skabelin, Alexander; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinskiy, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro

    2009-01-01

    The $e p\\to e^\\prime p \\rho^0$ reaction has been measured, using the 5.754 GeV electron beam of Jefferson Lab and the CLAS detector. This represents the largest ever set of data for this reaction in the valence region. Integrated and differential cross sections are presented. The $W$, $Q^2$ and $t$ dependences of the cross section are compared to theoretical calculations based on $t$-channel meson-exchange Regge theory on the one hand and on quark handbag diagrams related to Generalized Parton Distributions (GPDs) on the other hand. The Regge approach can describe at the $\\approx$ 30% level most of the features of the present data while the two GPD calculations that are presented in this article which succesfully reproduce the high energy data strongly underestimate the present data. The question is then raised whether this discrepancy originates from an incomplete or inexact way of modelling the GPDs or the associated hard scattering amplitude or whether the GPD formalism is simply in

  2. Quasi-elastic Neutrino Scattering - an Overview

    International Nuclear Information System (INIS)

    Sobczyk, Jan T.

    2011-01-01

    A non-technical overview of charge current quasi-elastic neutrino interaction is presented. Many body computations of multinucleon ejection which is proposed to explain recent large axial mass measurements are discussed. A few comments on recent experimental results reported at NuInt11 workshop are included.

  3. Elastic scattering and quasi-elastic transfers

    International Nuclear Information System (INIS)

    Mermaz, M.C.

    1978-01-01

    Experiments are presented which it will be possible to carry out at GANIL on the elastic scattering of heavy ions: diffraction phenomena if the absorption is great, refraction phenomena if absorption is low. The determination of the optical parameters can be performed. The study of the quasi-elastic transfer reactions will make it possible to know the dynamics of the nuclear reactions, form exotic nuclei and study their energy excitation spectrum, and analyse the scattering and reaction cross sections [fr

  4. Electroproduction of p0 mesons

    International Nuclear Information System (INIS)

    Cohen, I.; Erickson, R.; Messing, F.; Nordberg, E.; Siemann, R.; Smith-Kintner, J.; Stein, P.; Sadoff, A.; Drews, G.; Gebert, W.

    1980-03-01

    Cross-sections for rho 0 electroproduction measured in a streamer chamber experiment are separated into elastic (ep → eprho 0 ) and inelastic production channels. For the inelastic channel 1/sigma dsigma/dz, 1/sigma dsigma/dp 2 sub(t) and a density matrix element are shown and compared to quark-parton model predictions. The ratio of rho 0 to π 0 production is measured to be 2.0 +- 0.5. For the elastic channel, the total cross-section and t-dependence are presented. (orig.)

  5. Quasi-Elastic Light Scattering in Ophthalmology

    Science.gov (United States)

    Ansari, Rafat R.

    The eye is not just a "window to the soul"; it can also be a "window to the human body." The eye is built like a camera. Light which travels from the cornea to the retina traverses through tissues that are representative of nearly every tissue type and fluid type in the human body. Therefore, it is possible to diagnose ocular and systemic diseases through the eye. Quasi-elastic light scattering (QELS) also known as dynamic light scattering (DLS) is a laboratory technique routinely used in the characterization of macromolecular dispersions. QELS instrumentation has now become more compact, sensitive, flexible, and easy to use. These developments have made QELS/DLS an important tool in ophthalmic research where disease can be detected early and noninvasively before the clinical symptoms appear.

  6. Quasi-elastic and inelastic inclusive electron scattering from an oxygen jet target

    International Nuclear Information System (INIS)

    Anghinolfi, M.; Cenni, R.; Levi Sandri, P.; Longhi, A.; Mokeev, V.I.; Polli, E.; Reolon, A.; Ricco, G.; Simula, S.; Taiuti, M.; Teglia, A.; Zucchiatti, A.

    1996-01-01

    The results of an experiment on inclusive electron scattering from an oxygen jet target, performed in a wide range of energy and momentum transfer covering both quasi-elastic and Δ(1232) resonance regions, are reported. In the former region the theoretical predictions, obtained including effects of nucleon-nucleon correlations in both initial and final states, give a good description of the experimental data. In the inelastic region a broadening as well as a damping of the resonant part of the cross section with respect to the free nucleon case is observed. The need of more detailed calculations including nuclear structure effects on the electroproduction cross section of nucleon resonances is highlighted. (orig.)

  7. Measurement of Exclusive $\\rho^{0}\\rho^{0}$ Production in Mid-Virtuality Two-Photon Interactions at LEP

    CERN Document Server

    Achard, P.; Aguilar-Benitez, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M.G.; Anderhub, H.; Andreev, Valery P.; Anselmo, F.; Arefev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay, L.; Baldew, S.V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillere, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B.L.; Biasini, M.; Biglietti, M.; Biland, A.; Blaising, J.J.; Blyth, S.C.; Bobbink, G.J.; Bohm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J.G.; Brochu, F.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Capell, M.; Cara Romeo, G.; Carlino, G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Chamizo, M.; Chang, Y.H.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G.M.; Chen, H.F.; Chen, H.S.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; de la Cruz, B.; Cucciarelli, S.; de Asmundis, R.; Deglon, P.; Debreczeni, J.; Degre, A.; Dehmelt, K.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; Dionisi, C.; Dittmar, M.; Doria, A.; Dova, M.T.; Duchesneau, D.; Duda, M.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.; Engler, A.; Eppling, F.J.; Extermann, P.; Falagan, M.A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Fesefeldt, H.; Fiandrini, E.; Field, J.H.; Filthaut, F.; Fisher, P.H.; Fisher, W.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Iouri; Ganguli, S.N.; Garcia-Abia, Pablo; Gataullin, M.; Gentile, S.; Giagu, S.; Gong, Z.F.; Grenier, Gerald Jean; Grimm, O.; Gruenewald, M.W.; Guida, M.; Gupta, V.K.; Gurtu, A.; Gutay, L.J.; Haas, D.; Hatzifotiadou, D.; Hebbeker, T.; Herve, Alain; Hirschfelder, J.; Hofer, H.; Hohlmann, M.; Holzner, G.; Hou, S.R.; Jin, B.N.; Jindal, P.; Jones, Lawrence W.; de Jong, P.; Josa-Mutuberria, I.; Kaur, M.; Kienzle-Focacci, M.N.; Kim, J.K.; Kirkby, Jasper; Kittel, W.; Klimentov, A.; Konig, A.C.; Kopal, M.; Koutsenko, V.; Kraber, M.; Kraemer, R.W.; Kruger, A.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Le Goff, J.M.; Leiste, R.; Levtchenko, M.; Levtchenko, P.; Li, C.; Likhoded, S.; Lin, C.H.; Lin, W.T.; Linde, F.L.; Lista, L.; Liu, Z.A.; Lohmann, W.; Longo, E.; Lu, Y.S.; Luci, C.; Luminari, L.; Lustermann, W.; Ma, W.G.; Malgeri, L.; Malinin, A.; Mana, C.; Mans, J.; Martin, J.P.; Marzano, F.; Mazumdar, K.; McNeil, R.R.; Mele, S.; Merola, L.; Meschini, M.; Metzger, W.J.; Mihul, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G.B.; Muanza, G.S.; Muijs, A.J.M.; Musicar, B.; Musy, M.; Nagy, S.; Natale, S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak, T.; Kluge, Hannelies; Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci, P.; Paramatti, R.; Passaleva, G.; Patricelli, S.; Paul, Thomas Cantzon; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Piccolo, D.; Pierella, F.; Pioppi, M.; Piroue, P.A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofev, D.; Quartieri, J.; Rahal-Callot, G.; Rahaman, Mohammad Azizur; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P.G.; Ranieri, R.; Raspereza, A.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Riemann, S.; Riles, Keith; Roe, B.P.; Romero, L.; Rosca, A.; Rosemann, C.; Rosenbleck, C.; Rosier-Lees, S.; Roth, Stefan; Rubio, J.A.; Ruggiero, G.; Rykaczewski, H.; Sakharov, A.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Schafer, C.; Schegelsky, V.; Schopper, H.; Schotanus, D.J.; Sciacca, C.; Servoli, L.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.; Steuer, M.; Stickland, D.P.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sultanov, G.; Sun, L.Z.; Sushkov, S.; Suter, H.; Swain, J.D.; Szillasi, Z.; Tang, X.W.; Tarjan, P.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, Charles; Ting, Samuel C.C.; Ting, S.M.; Tonwar, S.C.; Toth, J.; Tully, C.; Tung, K.L.; Ulbricht, J.; Valente, E.; Van de Walle, R.T.; Vasquez, R.; Veszpremi, V.; Vesztergombi, G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobev, I.; Vorobyov, A.A.; Wadhwa, M.; Wang, Q.; Wang, X.L.; Wang, Z.M.; Weber, M.; Wynhoff, S.; Xia, L.; Xu, Z.Z.; Yamamoto, J.; Yang, B.Z.; Yang, C.G.; Yang, H.J.; Yang, M.; Yeh, S.C.; Zalite, An.; Zalite, Yu.; Zhang, Z.P.; Zhao, J.; Zhu, G.Y.; Zhu, R.Y.; Zhuang, H.L.; Zichichi, A.; Zimmermann, B.; Zoller, M.

    2004-01-01

    Exclusive rho^0 rho^0 production in two-photon collisions between a quasi-real and a mid-virtuality photon is studied with data collected at LEP at centre-of-mass energies 183GeV rho^0 rho^0 is determined as a function of the photon virtuality, q^2, and the two-photon centre-of-mass energy, Wgg, in the kinematic region: 0.2GeV^2 < q^2 < 0.85GeV^2 and 1.1GeV < Wgg < 3GeV.

  8. Charged pion electroproduction, a selective probe of nuclear spin isospin responses

    International Nuclear Information System (INIS)

    Chanfray, G.; Delorme, J.

    1983-05-01

    We study the reaction of pion electroproduction on nuclei in the quasi-elastic region. We show that detection of the pion in the direction of the virtual photon permits the separation of the spin longitudinal and transverse responses through a Rosenbluth plot. Emphasis is also put on consistency between medium effects and gauge invariance

  9. Quasi-elastic Charm Production In Neutrino-nucleon Scattering

    CERN Document Server

    Bischofberger, M

    2005-01-01

    A study of quasi elastic charm production in charged current neutrino-nucleon scattering is presented. A sample of about 1.3 million interactions recorded with the NOMAD detector in the CERN SPS wide band neutrino beam has been searched for quasi elastically produced charmed baryons ( L+c,Sc and S*c ). The search has been performed in two exclusive decay channels of the L+c, both including a L . Also, the semi-inclusive decay channels L+c,Sc,S *c→L+X have been studied. Kinematic selection criteria have been chosen in order to obtain samples enriched with quasi elastic charm events. Signal efficiencies and background expectations have been estimated by Monte Carlo simulations. The observed number of events in each searched channel has been found to agree with the background expectation from charged and neutral current reactions and an upper limit for the cross section has been derived. For the quasi elastic charm production cross section averaged over the neutrino energy spectrum (&lan...

  10. Quasi-elastic neutron line broadening in nematic liquid crystals

    International Nuclear Information System (INIS)

    Cvikl, B.; Dimic, V.; Dusic, M.; Kristof, E.; Srebotnjak, E.

    1979-01-01

    On the basis of a new random walk torsional oscillations model of the amplitude φ 0 of rigid flat molecules a quasi-elastic neutron line broadening has been calculated and the results compared to the measurements obtained on the sample of cholesteryl propionate. A good agreement was obtained. (author)

  11. Transverse target spin asymmetries in exclusive rho(0) muoproduction

    Czech Academy of Sciences Publication Activity Database

    Adolph, C.; Akhunzyanov, R.; Alekseev, M.; Alexakhin, V. Yu.; Alexandrov, Yu.; Alexeev, G. D.; Amoroso, A.; Andrieux, V.; Anosov, V. A.; Austregisilio, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Beck, R.; Bedfer, Y.; Berlin, A.; Bernhard, J.; Bertini, R.; Bicker, K.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bodlak, M.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Büchele, M.; Burtin, E.; Capozza, L.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Crespo, M.; Curiel, Q.; Dalla Torre, S.; Dasgupta, S. S.; Dasgupta, S.; Denisov, O.; Donskov, S.; Doshita, N.; Duic, V.; Dünnweber, W.; Dziewiecki, M.; Efremov, A.V.; Elia, C.; Eversheim, P.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger jr., M.; Fischer, H.; Franco, C.; Fresne von Hohenesche, N.; Friedrich, J.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Gorzellik, M.; Grabmüller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Guthörl, T.; Haas, F.; von Harrach, D.; Hahne, D.; Hashimoto, R.; Heinsius, F.; Herrmann, F.; Hess, C.; Hinterberger, F.; Höppner, Ch.; Horikawa, N.; d'Hose, N.; Huber, S.; Ishimoto, S.; Ivanov, A.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Joerg, P.; Joosten, R.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.; Khokhlov, Y.; Kisselev, Y.; Klein, F.; Klimaszewski, K.; Koivuniemi, J.; Kolosov, V.; Kondo, K.; Königsmann, K.; Konorov, I.; Konstantinov, V.; Kotzinian, A.; Kouznetsov, O.; Král, Z.; Krämer, M.; Kroumchtein, Z.; Kuchinski, N.; Kunne, F.; Kurek, K.; Kurjata, R. P.; Lednev, A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G.; Marchand, C.; Martin, A.; Marzec, J.; Matoušek, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Y.; Miyachi, Y.; Nagaytsev, A.; Nagel, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.; Nový, J.; Nowak, W. D.; Nunes, A.S.; Orlov, I.; Olshevsky, A.; Ostrick, M.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pešek, M.; Peshekhonov, D.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Reicherz, G.; Rocco, E.; Rodionov, V. K.; Rondio, E.; Rossiyskaya, N. S.; Ryabchikov, D.; Samoylenko, V.; Sandacz, A.; Sapozhnikov, M.; Sarkar, S.; Savin, I.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schlütter, T.; Schmidt, A.; Schmidt, K.; Schmiden, H.; Schmitt, L.; Schönning, K.; Schopferer, S.; Schott, M.; Shevchenko, O.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Sosio, S.; Sozzi, F.; Srnka, Aleš; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Szabelski, A.; Szameitat, T.; Sznajder, P.; Takekawa, S.; Ter Wolbeek, J.; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Vondra, J.; Wang, L.; Weisrock, T.; Wilfert, M.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Zhuravlev, N.; Ziembicki, M.

    2014-01-01

    Roč. 731, APR 4 (2014), s. 19-26 ISSN 0370-2693 R&D Projects: GA MŠk(CZ) LO1212 Keywords : generalized parton distributions * vector-meson electroproduction * scattering Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 6.131, year: 2014

  12. Exclusive rho(0) muoproduction on transversely polarised protons and deuterons

    Czech Academy of Sciences Publication Activity Database

    Adolph, C.; Alekseev, M.; Alexakhin, V. Yu.; Alexandrov, Yu.; Alexeev, G. D.; Amoroso, A.; Antonov, A. A.; Austregisilio, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Bedfer, Y.; Bernhard, J.; Bertini, R.; Bettinelli, M.; Bicker, K.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Büchele, M.; Burtin, E.; Capozza, L.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Crespo, M.; Dalla Torre, S.; Das, S.; Dasgupta, S. S.; Dasgupta, S.; Denisov, O.; Dhara, L.; Donskov, S.; Doshita, N.; Duic, V.; Dünnweber, W.; Dziewiecki, M.; Efremov, A.V.; Elia, C.; Eversheim, P.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger jr., M.; Fischer, H.; Franco, C.; Fresne von Hohenesche, N.; Friedrich, J.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmüller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Guthörl, T.; Haas, F.; von Harrach, D.; Heinsius, F.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Höppner, Ch.; d'Hose, N.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Jegou, G.; Joosten, R.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.; Khokhlov, Y.; Kisselev, Y.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.; Kolosov, V.; Kondo, K.; Königsmann, K.; Konorov, I.; Konstantinov, V.; Korzenev, A.; Kotzinian, A.; Kouznetsov, O.; Krämer, M.; Kroumchtein, Z.; Kunne, F.; Kurek, K.; Lauser, L.; Lednev, A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G.; Mann, A.; Marchand, C.; Martin, A.; Marzec, J.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Y.; Moinester, M.; Morreale, A.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Negrini, S.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.; Nowak, W. D.; Nunes, A.S.; Olshevsky, A.; Ostrick, M.; Padee, A.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Perevalova, E.; Pesaro, G.; Peshekhonov, D.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.; Pretz, J.; Quaresma, M.; Quintans, C.; Rajotte, J.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Richter, A.; Rocco, E.; Rondio, E.; Rossiyskaya, N. S.; Ryabchikov, D.; Samoylenko, V.; Sandacz, A.; Sapozhnikov, M.; Sarkar, S.; Savin, I.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schlütter, T.; Schmidt, K.; Schmitt, L.; Schönning, K.; Schopferer, S.; Schott, M.; Schröder, W.; Shevchenko, O.; Silva, L.; Sinha, L.; Sissakian, A.; Slunecka, M.; Smirnov, G.; Sosio, S.; Sozzi, F.; Srnka, Aleš; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Sznajder, P.; Takekawa, S.; Ter Wolbeek, J.; Tessaro, S.; Tessarotto, F.; Tkatchev, L.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Vlassov, N.; Wang, L.; Wilfert, M.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zhuravlev, N.; Zvyagin, A.

    2012-01-01

    Roč. 865, č. 1 (2012), s. 1-20 ISSN 0550-3213 Institutional support: RVO:68081731 Keywords : vector-meson electroproduction * generalized parton distributions * virtual compton-scattering Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 4.327, year: 2012

  13. Double spin asymmetry in exclusive $\\rho^0$ muoproduction at COMPASS

    CERN Document Server

    Alexakhin, V Yu; Alexandrov, Yu A; Alexeev, G D; Amoroso, A; Arbuzov, A; Badelek, B; Balestra, F; Ball, J; Baum, G; Barth, J; Bedfer, Y; Bernet, C; Bertini, R; Bettinelli, M; Birsa, R; Bisplinghoff, J; Bordalo, P; Bradamante, Franco; Bravar, A; Bressan, A; Brona, G; Burtin, E; Bussa, M P; Chapiro, A; Chiosso, M; Cicuttin, A; Colantoni, M L; Costa, S; Crespo, M L; D'Hose, N; Dalla Torre, S; Das, S; Das-Gupta, S S; De Masi, R; Dedek, N; Denisov, O Yu; Dhara, L; Díaz, V; Dinkelbach, A M; Donskov, S V; Dorofeev, V A; Doshita, N; Duic, V; Dünnweber, W; Eversheim, P D; Eyrich, W; Fabro, M; Faessler, M; Falaleev, V; Ferrero, A; Ferrero, L; Finger, M; Finger, M Jr; Fischer, H; Franco, C; Franz, J; Friedrich, J M; Frolov, V; Garfagnini, R; Gautheron, F; Gavrichtchouk, O P; Gazda, R; Gerassimov, S G; Geyer, R; Giorgi, M; Gobbo, B; Görtz, S; Gorin, A M; Grabmuller, S; Grajek, O A; Grasso, A; Grube, B; Gushterski, R; Guskov, A; Haas, F; Hannappel, J; Von Harrach, D; Hasegawa, T; Heckmann, J; Hedicke, S; Heinsius, F H; Hermann, R; Hess, C; Hinterberger, F; Von Hodenberg, M; Horikawa, N; Horikawa, S; Ilgner, C; Ioukaev, A I; Ishimoto, S; Ivanov, O; Ivanshin, Yu; Iwata, T; Jahn, R; Janata, A; Jasinski, P; Joosten, R; Jouravlev, N I; Kabuss, E M; Kang, D; Ketzer, B; Khaustov, G V; Khokhlov, Yu A; Kisselev, Yu; Klein, F; Klimaszewski, K; Koblitz, S; Koivuniemi, J H; Kolosov, V N; Komissarov, E V; Kondo, K; Knigsmann, K; Konorov, I; Konstantinov, V F; Korentchenko, A S; Korzenev, A; Kotzinian, A M; Koutchinski, N A; Kuznetsov, O; Kravchuk, N P; Kral, A; Kroumchtein, Z V; Kühn, R; Kunne, Fabienne; Kurek, K; Ladygin, M E; Lamanna, M; Le Goff, J M; Lednev, A A; Lehmann, A; Lichtenstadt, J; Liska, T; Ludwig, I; Maggiora, A; Maggiora, M; Magnon, A; Mallot, G K; Mann, A; Marchand, C; Marroncle, J; Martin, A; Marzec, J; Massmann, F; Matsuda, T; Maksimov, A N; Meyer, W; Mielech, A; Mikhailov, Yu V; Moinester, M A; Mutter, A; Nahle, O; Nagaytsev, A; Nagel, T; Nassalski, J P; Neliba, S; Nerling, F; Neubert, a S; Neyret, D P; Nikolaenko, V I; Nikolaev, K; Olshevskii, A G; Ostrick, M; Padee, A; Pagano, P; Panebianco, S; Panknin, R; Panzieri, D; Paul, S; Pawlukiewicz-Kaminska, B; Peshekhonov, V D; Piragino, G; Platchkov, S; Pochodzalla, J; Polak, J; Polyakov, V A; Pretz, J; Procureur, S; Quintans, C; Rajotte, J F; Rapatsky, V; Ramos, S; Reicherz, G; Richter, A; Robinet, F; Rocco, E; Rondio, E; Rozhdestvensky, A M; Ryabchikov, D I; Samoylenko, V D; Sandacz, A; Santos, H; Sapozhnikov, M G; Sarkar, S; Savin, I A; Schiavon, Paolo; Schill, C; Schmitt, L; Schonmeier, P; Schroder, W; Shevchenko, O Yu; Siebert, H W; Silva, L; Sinha, L; Sissakian, A N; Slunecka, M; Smirnov, G I; Sosio, S; Sozzi, F; Sugonyaev, V P; Srnka, A; Stinzing, F; Stolarski, M; Sulc, M; Sulej, R; Takabayashi, N; Tchalishev, V V; Tessaro, S; Tessarotto, F; Teufel, A; Tkatchev, L G; Venugopal, G; Virius, M; Vlassov, N V; Vossen, A; Webb, R; Weise, E; Weitzel, Q; Windmolders, R; Wirth, S; Wilicki, W; Zaremba, s K; Zavertyaev, M; Zemlyanichkina, E; Zhao, J; Ziegler, R; Zvyagin, A

    2007-01-01

    The longitudinal double spin asymmetry A_1^rho for exclusive leptoproduction of rho^0 mesons, mu + N -> mu + N + rho, is studied using the COMPASS 2002 and 2003 data. The measured reaction is incoherent exclusive rho^0 production on polarised deuterons. The Q^2 and x dependence of A_1^rho is presented in a wide kinematical range: 3x10^-3 < Q^2 < 7 (GeV/c)^2 and 5x10^-5 < x < 0.05. The presented results are the first measurements of A_1^rho at small Q2 (Q2 < 0.1 (GeV/c)^2) and small x (x < 3x10^-3). The asymmetry is in general compatible with zero in the whole kinematical range.

  14. Quasi-elastic measurements using neutron spin flippers

    International Nuclear Information System (INIS)

    Bleuel, M.; Fitzsimmons, M.R.; Lal, J.

    2008-01-01

    A method for low-resolution quasi-elastic measurements using commonly available components on a polarized neutron beam reflectometer is demonstrated. By amplitude modulation of the current in a neutron spin flipper placed between the neutron beam polarizer and polarization analyzer, the intensity of the neutron beam illuminating a sample is similarly modulated (or chopped). We show that the intensity contrast between subsequent chopped pulses is dramatically reduced by a sample that changes neutron velocity

  15. Nucleon in nuclei from quasi-elastic electron scattering

    International Nuclear Information System (INIS)

    Gerard, A.

    1987-04-01

    One challenging problem in modern nuclear physics is to understand how the internal structure of the nucleon interferes with the dynamics of nucleons in a nucleus. The purpose of this paper is to review the present status of data in quasi-elastic electron scattering, to connect them with recent theoretical developments and to outline some future directions of research not accessible to present electron facilities

  16. Observation of the ${B^0 \\to \\rho^0 \\rho^0}$ decay from an amplitude analysis of ${B^0 \\to (\\pi^+\\pi^-)(\\pi^+\\pi^-)}$ decays

    CERN Document Server

    Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Bizzeti, Andrea; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casanova Mohr, Raimon; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cavallero, Giovanni; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Counts, Ian; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Di Ruscio, Francesco; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gastaldi, Ugo; Gauld, Rhorry; Gavardi, Laura; Gazzoni, Giulio; Geraci, Angelo; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Gianì, Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, Vladimir; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Humair, Thibaud; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Kenzie, Matthew; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lowdon, Peter; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Maciuc, Florin; Maev, Oleg; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathad, Abhijit; Mathe, Zoltan; Matteuzzi, Clara; Mauri, Andrea; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Mitzel, Dominik Stefan; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Katharina; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Osorio Rodrigues, Bruno; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Aranzazu; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parkes, Christopher; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Petridis, Konstantin; Petrolini, Alessandro; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Poikela, Tuomas; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skillicorn, Ian; Skwarnicki, Tomasz; Smith, Anthony; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Sterpka, Christopher Francis; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szumlak, Tomasz; T'Jampens, Stephane; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Todd, Jacob; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Trabelsi, Karim; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viana Barbosa, Joao Vitor; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Weiden, Andreas; Whitehead, Mark; Wiedner, Dirk; Wilkinson, Guy; Wilkinson, Michael; Williams, Mark Richard James; Williams, Matthew; Williams, Mike; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang

    2015-01-01

    Proton-proton collision data recorded in 2011 and 2012 by the LHCb experiment, corresponding to an integrated luminosity of 3.0 fb$^{-1}$i, are analysed to search for the charmless ${B^0 \\to \\rho^0 \\rho^0}$ decay. More than 600 ${B^0 \\to (\\pi^+\\pi^-)(\\pi^+\\pi^-)}$ signal decays are selected and used to perform an amplitude analysis from which the ${B^0 \\to \\rho^0 \\rho^0}$ decay is observed for the first time with 7.1 standard deviations significance. The fraction of ${B^0 \\to \\rho^0 \\rho^0}$ decays yielding a longitudinally polarised final state is measured to be $fL = 0.745^{+0.048}_{-0.058} ({\\rm stat}) \\pm 0.034 ({\\rm syst})$. The ${B^0 \\to \\rho^0 \\rho^0}$ branching fraction, using the ${B^0 \\to \\phi K^*(892)^{0}}$ decay as reference, is also reported as $\\mathcal B (B^0 \\to \\rho^0 \\rho^0) = (0.94 \\pm 0.17 ({\\rm stat}) \\pm 0.09 ({\\rm syst}) \\pm 0.06 ({\\rm BF})) \\times 10^{-6}$.

  17. Studying neutrino oscillations using quasi-elastic events in MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Kumaratunga, Sujeewa Terasita [Univ. of Minnesota, Minneapolis, MN (United States)

    2008-02-01

    MINOS (Main Injector Neutrino Oscillation Search), is a long baseline neutrino experiment designed to search for neutrino oscillations using two detectors at Fermi National Accelerator Laboratory, IL (Near Detector) and Soudan, MN (Far Detector). It will study vμ → vτ oscillations and make a measurement on the oscillation parameters, Δm$2\\atop{23}$ and sin223, via a vμ beam made at Fermilab. Charge current neutrino interactions in the MINOS detectors are of three types: quasi-elastic scattering (QEL), resonance scattering (RES) and deep inelastic scattering (DIS). Of these, quasi-elastic scattering leaves the cleanest signal with just one μ and one proton in the final state, thus rendering the reconstruction of the neutrino energy more accurate. This thesis will outline a method to separate QEL events from the others in the two detectors and perform a calculation of Δm$2\\atop{23}$ and sin223 using those events. The period under consideration was May 2005 to February 2006. The number of observed quasi-elastic events with energies below 10 GeV was 29, where the expected number was 60 ± 3. A fit to the energy distribution of these events gives Δm$2\\atop{23}$ = 2.91$+0.49\\atop{-0.53}$(stat)$+0.08\\atop{-0.09}$(sys) x 10-3 eV2 and sin223 = 0.990-0.180(stat)-0.030(sys).

  18. Systematics of quasi-elastic processes induced by heavy ions

    International Nuclear Information System (INIS)

    Baltz, A.J.

    1976-01-01

    An attempt is made to delineate the areas in the systematics of quasi-elastic processes induced by heavy ions that are well described theoretically from the specific features that seem not to be understood. One- and two-particle transfer reactions are considered. A general systematic seen in transfer angular distribution data and theory, some successes and failures of the DWBA and coupled-channels theories in describing heavy-ion-reaction data, and the specific example 232 Th( 40 Ar,K) and implications for deep inelastic reactions with even heavier projectiles such as Kr and Xe are considered

  19. Selectron production in quasi-elastic electron-proton scattering

    International Nuclear Information System (INIS)

    Bartels, J.; Hollik, W.

    1985-08-01

    We calculate the cross section for the production of selectrons in quasi-elastic electron proton scattering at HERA energies. In the region of very small momentum transfer the cross section turns out to be large: e.g. sigma=36 pb for a selectron mass of 60 GeV, tsub(min) 2 ), and photino mass small compared to the selectron mass. Together with the clean experimental signature, this large cross section makes the reaction e+P->e+γ tilde+P one of the most promising HERA-processes in connection with the search for supersymmetric particles. (orig.)

  20. Exclusive $\\rho^0$ muoproduction on transversely polarised protons and deuterons

    CERN Document Server

    Adolph, C.; Alexakhin, V.Yu.; Alexandrov, Yu.; Alexeev, G.D.; Amoroso, A.; Antonov, A.A.; Austregesilo, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Bedfer, Y.; Bernhard, J.; Bertini, R.; Bettinelli, M.; Bicker, K.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Buchele, M.; Burtin, E.; Capozza, L.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Crespo, M.L.; Dalla Torre, S.; Das, S.; Dasgupta, S.S.; Dasgupta, S.; Denisov, O.Yu.; Dhara, L.; Donskov, S.V.; Doshita, N.; Duic, V.; Dunnweber, W.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger, M., Jr.; Fischer, H.; Franco, C.; du Fresne von Hohenesche, N.; Friedrich, J.M.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.P.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmuller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Guthorl, T.; Haas, F.; von Harrach, D.; Heinsius, F.H.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Hoppner, Ch.; d'Hose, N.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Jegou, G.; Joosten, R.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu.A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.H.; Kolosov, V.N.; Kondo, K.; Konigsmann, K.; Konorov, I.; Konstantinov, V.F.; Korzenev, A.; Kotzinian, A.M.; Kouznetsov, O.; Kramer, M.; Kroumchtein, Z.V.; Kunne, F.; Kurek, K.; Lauser, L.; Lednev, A.A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G.K.; Mann, A.; Marchand, C.; Martin, A.; Marzec, J.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Yu.V.; Moinester, M.A.; Morreale, A.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Negrini, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.I.; Nowak, W.D.; Nunes, A.S.; Olshevsky, A.G.; Ostrick, M.; Padee, A.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Perevalova, E.; Pesaro, G.; Peshekhonov, D.V.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.A.; Pretz, J.; Quaresma, M.; Quintans, C.; Rajotte, J.F.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Richter, A.; Rocco, E.; Rondio, E.; Rossiyskaya, N.S.; Ryabchikov, D.I.; Samoylenko, V.D.; Sandacz, A.; Sapozhnikov, M.G.; Sarkar, S.; Savin, I.A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schluter, T.; Schmidt, K.; Schmitt, L.; Schonning, K.; Schopferer, S.; Schott, M.; Schroder, W.; Shevchenko, O.Yu.; Silva, L.; Sinha, L.; Sissakian, A.N.; Slunecka, M.; Smirnov, G.I.; Sosio, S.; Sozzi, F.; Srnka, A.; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Sznajder, P.; Takekawa, S.; Ter Wolbeek, J.; Tessaro, S.; Tessarotto, F.; Tkatchev, L.G.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Vlassov, N.V.; Wang, L.; Wilfert, M.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zhuravlev, N.; Zvyagin, A.

    2012-01-01

    The transverse target spin azimuthal asymmetry A_UT in hard exclusive production of rho^0 mesons was measured at COMPASS by scattering 160 GeV/c muons off transversely polarised protons and deuterons. The measured asymmetry is sensitive to the nucleon helicity-flip generalised parton distributions E^q, which are related to the orbital angular momentum of quarks in the nucleon. The Q^2, x_B and p_t^2 dependence of A_UT is presented in a wide kinematic range. Results for deuterons are obtained for the first time. The measured asymmetry is small in the whole kinematic range for both protons and deuterons, which is consistent with the theoretical interpretation that contributions from GPDs E^u and E^d approximately cancel.

  1. Transverse target spin asymmetries in exclusive $\\rho^0$ muoproduction

    CERN Document Server

    Adolph, C; Alexakhin, V Yu; Alexandrov, Yu; Alexeev, G D; Amoroso, A; Andrieux, V; Austregesilo, A; Badelek, B; Balestra, F; Barth, J; Baum, G; Bedfer, Y; Berlin, A; Bernhard, J; Bertini, R; Bicker, K; Bieling, J; Birsa, R; Bisplinghoff, J; Boer, M; Bordalo, P; Bradamante, F; Braun, C; Bravar, A; Bressan, A; Büchele, M; Burtin, E; Capozza, L; Chiosso, M; Chung, S U; Cicuttin, A; Crespo, M L; Dalla Torre, S; Dasgupta, S S; Dasgupta, S; Denisov, O Yu; Donskov, S V; Doshita, N; Duic, V; Dünnweber, W; Dziewiecki, M; Efremov, A; Elia, C; Eversheim, P D; Eyrich, W; Faessler, M; Ferrero, A; Filin, A; Finger, M; Finger, M jr; Fischer, H; Franco, C; du Fresne von Hohenesche, N; Friedrich, J M; Frolov, V; Garfagnini, R; Gautheron, F; Gavrichtchouk, O P; Gerassimov, S; Geyer, R; Giorgi, M; Gnesi, I; Gobbo, B; Goertz, S; Grabmüller, S; Grasso, A; Grube, B; Gushterski, R; Guskov, A; Guthörl, T; Haas, F; von Harrach, D; Hahne, D; Heinsius, F H; Herrmann, F; Hess, C; Hinterberger, F; Höppner, Ch; Horikawa, N; d'Hose, N; Huber, S; Ishimoto, S; Ivanshin, Yu; Iwata, T; Jahn, R; Jary, V; Jasinski, P; Joosten, R; Kabuss, E; Kang, D; Ketzer, B; Khaustov, G V; Khokhlov, Yu A; Kisselev, Yu; Klein, F; Klimaszewski, K; Koivuniemi, J H; Kolosov, V N; Kondo, K; Königsmann, K; Konorov, I; Konstantinov, V F; Kotzinian, A M; Kouznetsov, O; Krämer, M; Kroumchtein, Z V; Kuchinski, N; Kunne, F; Kurek, K; Kurjata, R P; Lednev, A A; Lehmann, A; Levorato, S; Lichtenstadt, J; Maggiora, A; Magnon, A; Makke, N; Mallot, G K; Marchand, C; Martin, A; Marzec, J; Matousek, J; Matsuda, H; Matsuda, T; Meshcheryakov, G; Meyer, W; Michigami, T; Mikhailov, Yu V; Miyachi, Y; Morreale, A; Nagaytsev, A; Nagel, T; Nerling, F; Neubert, S; Neyret, D; Nikolaenko, V I; Novy, J; Nowak, W D; Nunes, A.S; Olshevsky, A G; Ostrick, M; Panknin, R; Panzieri, D; Parsamyan, B; Paul, S; Pesek, M; Piragino, G; Platchkov, S; Pochodzalla, J; Polak, J; Polyakov, V A; Pretz, J; Quaresma, M; Quintans, C; Ramos, S; Reicherz, G; Rocco, E; Rodionov, V; Rondio, E; Rossiyskaya, N S; Ryabchikov, D I; Samoylenko, V D; Sandacz, A; Sapozhnikov, M G; Sarkar, S; Savin, I A; Sbrizzai, G; Schiavon, P; Schill, C; Schlüter, T; Schmidt, A; Schmidt, K; Schmitt, L; Schmïden, H; Schönning, K; Schopferer, S; Schott, M; Shevchenko, O Yu; Silva, L; Sinha, L; Sirtl, S; Slunecka, M; Sosio, S; Sozzi, F; Srnka, A; Steiger, L; Stolarski, M; Sulc, M; Sulej, R; Suzuki, H; Sznajder, P; Takekawa, S; Ter Wolbeek, J; Tessaro, S; Tessarotto, F; Thibaud, F; Uhl, S; Uman, I; Vandenbroucke, M; Virius, M; Vondra, J; Wang, L; Weisrock, T; Wilfert, M; Windmolders, R; Wislicki, W; Wollny, H; Zaremba, K; Zavertyaev, M; Zemlyanichkina, E; Zhuravlev, N; Ziembicki, M

    2014-01-01

    Exclusive production of $\\rho^0$ mesons was studied at the COMPASS experiment by scattering 160 GeV/$c$ muons off transversely polarised protons. Five single-spin and three double-spin azimuthal asymmetries were measured as a function of $Q^2$, $x_{Bj}$, or $p_{T}^{2}$. The $\\sin \\phi_S$ asymmetry is found to be $-0.019 \\pm 0.008(stat.) \\pm 0.003(syst.)$. All other asymmetries are also found to be of small magnitude and consistent with zero within experimental uncertainties. Very recent calculations using a GPD-based model agree well with the present results. The data is interpreted as evidence for the existence of chiral-odd, transverse generalized parton distributions.

  2. Quasi-elastic spectral change of stored UCN

    International Nuclear Information System (INIS)

    Geltenbort, P.; Butterworth, J.; Steyerl, A.; Kwon, O.; Yerozolimsky, B.; Achiwa, N.

    2001-01-01

    UCN within a narrow spectral range were stored in a Fomblin grease coated trap. After filling the trap the bandwidth of storable UCN could be reduced to zero by an absorber. This procedure did, however, not remove all UCN. As in our previous measurements, the remaining UCN were found to leave the trap with an efflux time constant significantly larger than the value measured for the initial UCN spectrum. The remaining fraction of UCN was reduced to zero only when the absorber was brought down almost to the bottom of the trap. The data can be explained, qualitatively, by quasi-elastic UCN down-scattering by about 4 neV during the filling process. The deduced probability for this process is compared to a calculation for a model of hydrogen diffusing within a thin hydrogenous layer on top of the Fomblin grease. (author)

  3. The Measurement of the Quasi-Elastic Neutrino-Nucleon Scattering Cross Section at the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Suwonjandee, Narumon [Cincinnati U.

    2004-01-01

    The quasi-elastic neutrino nucleon cross section measurement has been measured in the low energy region less than 100 Ge V. The data agree well with the model proposed by C. H. Llewellyn Smith. This model predicts that the quasi-elastic cross section should be constant in the high enery region. The NuTeV experiment at Fermilab provides data which allows us to measure the quasi-elastic cross section for both neutrinos and anti-neutrinos at high energy. We find that $\\sigma^{Neucleon}_{qe}(v) = 0.94 \\pm 0.03(stat.) \\pm 0.07(syst.)$, and $\\sigma^{Neucleon}_{qe}(\\bar\

  4. Inclusive rho0 production in anti pp interactions at 22.4 GeV/c

    International Nuclear Information System (INIS)

    Ermilova, D.I.; Filippova, V.V.; Samojlov, V.V.

    1978-01-01

    Inclusive rho 0 production has been investigated in anti pp reactions at 22.4 GeV/c. The total cross section for rho 0 production is 8.1+-2.0 mb. The average number of rhosup(0') s per event is 0.17+-0.03. The average transverse momentum, as obtained by extrapolation of a simple exponential to the psub(T)sup(2) distribution, is 0.52+-0.12 GeV. The Feynman x and center of mass rapidity distributions show rho 0 to be ''centrally'' produced

  5. Exchange current contributions to quasi-elastic electron scattering

    International Nuclear Information System (INIS)

    Conte, J.S. Jr.

    1981-01-01

    Because electromagnetic interactions are weak and well understood, inelastic electron scattering has been very useful in elucidating aspects of nuclear structure. In the region of large electron energy loss, an extremely simple reaction picture (quasi-free knockout of a single nucleon or electroproduction of an isobar) and a simple nuclear model (Fermi gas) have provided both a good fit to experimental data and a dynamical determination of the nuclear Fermi momentum (k/sub F/). However, there exists an anomalous region where this picture fails. Two body correlations have not seemed to help give any better agreement. We have investigated the following questions: Do exchange current processes contribute importantly in this region. Do they help produce agreement with experiment. Also, how do they effect our previous picture of quasifree knockout. We calculate the effects of exchange currents in this region using the standard Feynman graph rules. We have included all important long range exchange currents: pair, pionic, and isobar exchange currents. We found it necessary to make non-relativistic reductions of these currents in order to facilitate calculations. The resulting multidimensional integrals were done using Monte Carlo techniques. All exchange currents which were investigated were found to be appreciable in the anomalous region, and also important in the quasi-free peak region. Inclusion of these amplitudes would supply all of the missing cross section in the anomalous region: however, it would destroy the agreement between theory and experiment in the region of the quasi-free nucleon peak, and thereby cast suspicion on the aforementioned dynamical determination of k/sub F/

  6. Inclusive rho0 production in anti νsub(μ)p charged current interactions

    International Nuclear Information System (INIS)

    Graessler, H.; Lanske, D.; Schulte, R.; Barnham, K.W.J.; Clayton, E.F.; Hamisi, F.; Miller, D.B.; Mobayyen, M.M.; Corrigan, G.; Myatt, G.; Radojicic, D.; Saitta, B.; Wells, J.

    1986-01-01

    Inclusive rho 0 production has been studied in antineutrino-proton charged current interactions, using a sample of 3340 events obtained in BEBC filled with hydrogen and exposed to the CERN wideband antineutrino beam. An average multiplicity of 0.11+-0.02 rho 0 per event at a mean hadronic mass W of 4.2 GeV is observed. The rho 0 production characteristics are determined as functions of psub(T), chisub(F), and z. The ratio rho 0 /'π 0 ' is found to be low at small z values consistent with centrally produced pions coming mainly from resonances. At large z values this ratio approaches 0.45+-0.15 which is compatible with a vector/pseudoscalar meson direct production ratio of one. The results are compared with those obtained from neutrino-proton interactions in the same experimental set-up. (orig.)

  7. etaγ decays of rho0, ω, and phi mesons

    International Nuclear Information System (INIS)

    Andrews, D.E.; Fukushima, Y.; Harvey, J.; Lobkowicz, F.; May, E.N.; Nelson, C.A. Jr.; Thorndike, E.H.

    1977-01-01

    etaγ decays of rho 0 , ω, and phi are studied. We find GAMMA (phi→etaγ) =55 +- 12 keV. Our data admit two solutions for (rho 0 , ω) →etaγ: Either GAMMA (rho 0 →etaγ) =50 +- 13 keV, GAMMA (ω→etaγ) =3.0 +2 /sup ./ 5 /sub -/ 1 /sub ./ 8 keV, and the (ω,rho) →etaγ relative decay phase is near zero; or GAMMA (rho 0 →etaγ) =76 +- 15 keV, GAMMA (ω→etaγ) =29 +- 7 keV, and the decay phase is near 180degree

  8. Report of study meeting on nuclear physics of quasi-elastic scattering

    International Nuclear Information System (INIS)

    1992-10-01

    This meeting was held for three days from June 8 to 10, 1992, as one of the study meetings of Research Center for Nuclear Physics, Osaka University. The lectures were given on spin observables in quasi-elastic scattering, calculation of spin observables in 12 C, 40 Ca(p,n) reaction in quasifree scattering region, present state of quasi-elastic scattering, first results of (p,n) quasifree scattering with the new facility of the RCNP, spin-isospin response function and effect of Δ-hole configuration in finite nuclei, effective polarization of nuclei and observed amount of spin, (p,2p) measurement in the RCNP, quasi-elastic scattering in 2 H, 3 He and 4 He of polarized protons, quasifree Δ formation, 3 He(gamma, pπ ± ) reaction in Δ region, search for isobar components in 3 He by quasifree knockout studies, nonquasi-elastic process in photonuclear reaction, QF and NQF processes in gamma d→π + π - pn, coincidence scattering experiment in quasi-elastic scattering region, exclusive electron scattering of 3 He with full inclusion of final state interaction, quasi-elastic electron scattering and internucleon correlation and 13 other themes. (K.I.)

  9. Shadowing in electroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Vilela Mendes, R; Leao, J P [Instituto de Fisica e Matematica, Av. Gama Pinto 2, Lisbon 4 (Portugal)

    1977-09-01

    The notorious absence of shadowing effects in electroproduction may have either a deep dynamical origin or a very simple geometrical one. We argue in favour of a simple origin for this effect, having to do with the geometrical nature of the source that generates the virtual photons in electroproduction.

  10. Inclusive and semi-inclusive rho0 production in π-p interactions at 147 GeV/c

    International Nuclear Information System (INIS)

    Fong, D.; Heller, M.; Shapiro, A.M.; Widgoff, M.; Bruyant, F.; Bogert, D.; Johnson, M.; Burnstein, R.; Fu, C.; Petersen, D.; Robertson, M.; Rubin, H.; Sard, R.; Snyder, A.; Tortora, J.; Alyea, D.; Chien, C.-Y.; Lucas, P.; Pevsner, A.; Zdanis, R.; Brau, J.; Grunhaus, J.; Hafen, E.S.; Hulsizer, R.I.; Karshon, U.; Kistiakowsky, V.; Levy, A.; Napier, A.; Pless, I.A.; Trepagnier, P.C.; Wolfson, J.; Yamamoto, R.K.; Cohn, H.; Ou, T.C.; Plano, R.; Watts, T.; Brucker, E.; Koller, E.; Stamer, P.; Taylor, S.; Bugg, W.; Condo, G.; Handler, T.; Hart, E.; Kraybill, H.; Ljung, D.; Ludlam, T.; Taft, H.D.

    1975-01-01

    Data on inclusive and semi-inclusive rho 0 production in 147 GeV/c π - p interactions are presented. A total cross section of 7.3+-1.3 mb is found. Most of this cross section is found in the lower topology events ( 2 dependence of rho 0 production, sub(rho 0 ) per event, and the rho 0 /π + ratios are also discussed. (Auth.)

  11. Interpretation of quasi-elastic barrier distributions for weakly bound systems

    International Nuclear Information System (INIS)

    Monteiro, D.S.; Gomes, P.R.S.; Lubian, J.

    2009-01-01

    Full text: We verify that quasi-elastic (elastic + inelastic) backscattering barrier distributions for weakly bound systems do not strictly correspond to fusion barrier distributions, but rather to reaction threshold distribution, as proposed by Zagrebaev in a recent paper concerning very heavy systems. In this work, we investigate whether Zagrebaevs interpretation is valid by comparing experimental results obtained in two very recent works with the 6 Li + 144 Sm system. Monteiro et al derived the quasi-elastic barrier distribution (or reaction threshold distribution, following Zagrebaevs interpretation) by adding elastic and inelastic backscattering for this system. Rath et al obtained fusion barrier distribution for the same system from the measured complete fusion cross section for the same system. We conclude that the quasi-elastic barrier distributions can be associated with fusion barrier distributions only in situations where there are no relevant reaction channels apart from fusion. This is not the situation for very heavy nor for weakly bound systems. (author)

  12. Study of the Quasi-Elastic Scattering in the NOvA Detector Prototype

    Energy Technology Data Exchange (ETDEWEB)

    Betancourt, Minerba [Univ. of Minnesota, Minneapolis, MN (United States)

    2013-06-01

    NOvA is a 810 km long base-line neutrino oscillation experiment with two detectors (far 14 KTon and near detector 300 Ton) currently being installed in the NUMI o -axis neutrino beam produced at Fermilab. A 222 Ton prototype NOvA detector (NDOS) was built and operated in the neutrino beam for over a year to understand the response of the detector and its construction. The goal of this thesis is to study the muon neutrino interaction data collected in this test, specifically the identification of quasi-elastic charged-current interactions and measure the behavior of the quasi-elastic muon neutrino cross section.

  13. Quasi-elastic neutrino production of charmed baryons from the point of view of local duality

    International Nuclear Information System (INIS)

    Kovalenko, S.G.

    1990-01-01

    The cross sections of quasi-elastic neutrino production of Λ c + , Σ c + , Σ c ++ - charmed baryons have been obtained on the basis of Bloom-Gilman local duality and approximate SU 4 -symmetry of strong interactions. 17 refs.; 3 figs

  14. Cross-section measurement for quasi-elastic production of charmed baryons in $\

    CERN Document Server

    Kayis-Topaksu, A; Van Dantzig, R; De Jong, M; Melzer, O; Oldeman, R G C; Pesen, E; Spada, F R; Visschers, J L; Güler, M; Köse, U; Serin-Zeyrek, M; Sever, R; Tolun, P; Zeyrek, M T; Catanesi, M G; De Serio, M; Ieva, M; Muciaccia, M T; Radicioni, E; Simone, S; Bülte, A; Winter, Klaus; Van de Vyver, B; Vilain, P; Wilquet, G; Pittoni, G L; Saitta, B; Di Capua, E; Ogawa, S; Shibuya, H; Artamonov, A V; Chizhov, M; Doucet, M; Hristova, I R; Kawamura, T; Kolev, D; Meinhard, H; Panman, J; Papadopoulos, I M; Ricciardi, S; Rozanov, A; Tsenov, R V; Uiterwijk, J W E; Zucchelli, P; Goldberg, J; Chikawa, M; Arik, E; Song, J S; Yoon, C S; Kodama, K; Ushida, N; Aoki, S; Hara, T; Delbar, T; Favart, D; Grégoire, G; Kalinin, S; Makhlyoueva, I V; Gorbunov, P; Khovanskii, V D; Shamanov, V V; Tsukerman, I; Bruski, N; Frekers, D; Hoshino, K; Kawada, J; Komatsu, M; Miyanishi, M; Nakamura, M; Nakano, T; Narita, K; Niu, K; Niwa, K; Nonaka, N; Sato, O; Toshito, T; Buontempo, S; Cocco, A G; D'Ambrosio, N; De Lellis, G; De Rosa, G; Di Capua, F; Ereditato, A; Fiorillo, G; Marotta, A; Messina, M; Migliozzi, P; Pistillo, C; Scotto-Lavina, L; Strolin, P; Tioukov, V; Nakamura, K; Okusawa, T; Dore, U; Loverre, P F; Ludovici, L; Righini, P; Rosa, G; Santacesaria, R; Satta, A; Barbuto, E; Bozza, C; Grella, G; Romano, G; Sirignano, C; Sorrentino, S; Sato, Y; Tezuka, I

    2003-01-01

    A study of quasi-elastic production of charmed baryons in charged-current interactions of neutrinos with the nuclear emulsion target of CHORUS is presented. In a sample of about 46000 interactions located in the emulsion, candidates for decays of short-lived particles were identified by using new automatic scanning systems and later confirmed through visual inspection. Criteria based both on topologival and kinematical characteristics of quasi-elastic charm production allowed a clear separation between events of this type and those in which charm is produced in deep inelastic processes. A final sample containing 13 candidates consistent with quasi-elastic production of a charmed baryon with an estimated background of 1.7 events was obtained. At the average neutrino energy of 27GeV the cross section for total quasi-elastic production of charmed baryons relative to the nuN charged-current cross-section was measured to be sigma(QE)/sigma(CC)=(0.23^+0.12_-0.06(stat)^+0.02_-0.03(syst))x10^-2. Through an analysis o...

  15. Modifications of nucleons in nuclei in quasi-elastic electron-nucleus scattering

    International Nuclear Information System (INIS)

    Mulders, P.J.

    1988-01-01

    In inelastic electron scattering two scaling regions are observed in which the scattering is dominated by quasi-elastic scattering. For large momentum transfers, √Q 2 > 2 GeV/c, the scattering process is dominated by quasi-elastic scattering off quarks, whereas for √Q 2 ≅ 0.5 GeV/c the dominant contribution is quasi-elastic scattering off nucleons. This corresponds nicely to our first order picture of the nucleus consisting of nucleons, which in turn are composed of quarks. In the nucleon-scaling region, possible modifications of nucleon properties show up through a study of the Q 2 dependence and the relative strength of the transverse and longitudinal cross sections. Results of both inclusive (e,e') and exclusive (e,e'p) experiments in the quasi-elastic scattering region indeed show a behavior that could indicate modifications of intrinsic properties of individual nucleons in the nucleus, although the question remains if one has correctly disentangled the effects of the (long range) interactions between nucleons and those connected to the internal structure of nucleons. Even so, a simple (one-parameter) size rescaling for nucleons appears to be inconsistent with the data and also with some known conventional nuclear physics observables. Therefore the inclusion of two-nucleon correlations appears necessary in order to be able to understand the data. Such correlations can for instance be due to the effect of the Pauli principle on the quark level. (orig.)

  16. Nuclear re-interaction effects in quasi-elastic neutrino nucleus scattering

    Energy Technology Data Exchange (ETDEWEB)

    Co, G.; Bleve, C.; De Mitri, I.; Martello, D

    2002-11-01

    The quasi-elastic {nu}-nucleus cross section has been calculated by using a Fermi gas model corrected to consider the re-scattering between the emitted nucleon and the rest nucleus. As an example of the relevance of this effect we show results for the muon production cross section on {sup 16}O target.

  17. Study of the diffusion movements of water by quasi-elastic scattering of slow neutrons

    International Nuclear Information System (INIS)

    Yamazaki, Ione Makiko

    1980-01-01

    The diffusion movements of water at three different temperatures in the liquid state have been studied by slow neutron quasi-elastic scattering. The measurements have been performed using the IPEN Triple Axis Spectrometer. Broadening and integrated intensity of the quasi-elastic line have been determined for several momentum transfer (K) in the range 0,7627 ≤ K ≤ 2,993 A -1 . The broadening of the quasi-elastic peaks as function of momentum transfer (K) observed at various temperatures has been interpreted in terms of globular diffusion models. The results obtained at 30 deg C have been explained in a consistent way considering the translational and rotational globular diffusion movements. To describe the results obtained at 55 deg and 70 deg C only the translational globular diffusion model was sufficient. This analysis indicates the existence in water of globules with distance of the farest proton position to the center of gravity of the globule 4,5 A, corroborating the idea of quasi-crystalline structure for water. The Debye-Waller factor has been obtained through the analysis of the integrated intensity of quasi-elastic scattering peaks over the K 2 measured range. From this analysis an estimative of the mean square displacement was obtained. (author)

  18. Photoproduction of $\\rho^0$ in ultra--peripheral nuclear collisions at ALICE

    CERN Document Server

    Skjerdal, Kyrre

    2013-01-01

    Photoproduction of $\\rho^0$ mesons in ultra-peripheral Pb+Pb collisions has been studied by the ALICE Collaboration at the CERN LHC. The strong photon flux associated with relativistic charged nuclei leads to a very large cross section for exclusive photoproduction of $\\rho^0$ meson in interactions of the type $Pb + Pb \\rightarrow Pb + Pb + \\rho^0$. For a $\\rho^0$ produced at mid-rapidity at the LHC, the photon-nucleus center of mass energy is higher than in any previous experiment. The ALICE detector is a general purpose detector dedicated to study heavy--ion collisions. ALICE has excellent performance in the low $p_T$ region, and can reconstruct charged particle tracks with 0.1 GeV/c $\\leq p_T \\leq 100$ GeV/c. In this analysis all tracks were required to be within ALICE's central barrel. Analysis of data from the first heavy ion run at the LHC in 2010 will be discussed in this paper.

  19. Exclusive $\\rho^0$ Meson Photoproduction with a Leading Neutron at HERA

    CERN Document Server

    Andreev, V.; Begzsuren, K.; Belousov, A.; Bolz, A.; Boudry, V.; Brandt, G.; Brisson, V.; Britzger, D.; Buniatyan, A.; Bylinkin, A.; Bystritskaya, L.; Campbell, A.J.; Cantun Avila, K.B.; Cerny, K.; Chekelian, V.; Contreras, J.G.; Cvach, J.; Dainton, J.B.; Daum, K.; Diaconu, C.; Dobre, M.; Dodonov, V.; Eckerlin, G.; Egli, S.; Elsen, E.; Favart, L.; Fedotov, A.; Feltesse, J.; Ferencei, J.; Fleischer, M.; Fomenko, A.; Gabathuler, E.; Gayler, J.; Ghazaryan, S.; Goerlich, L.; Gogitidze, N.; Gouzevitch, M.; Grab, C.; Grebenyuk, A.; Greenshaw, T.; Grindhammer, G.; Haidt, D.; Henderson, R.C.W.; Hladký, J.; Hoffmann, D.; Horisberger, R.; Hreus, T.; Huber, F.; Jacquet, M.; Janssen, X.; Jung, H.; Kapichine, M.; Kiesling, C.; Klein, M.; Kleinwort, C.; Kogler, R.; Kostka, P.; Kretzschmar, J.; Krüger, K.; Landon, M.P.J.; Lange, W.; Laycock, P.; Lebedev, A.; Levonian, S.; Lipka, K.; List, B.; List, J.; Lobodzinski, B.; Malinovski, E.; Martyn, H.-U.; Maxfield, S.J.; Mehta, A.; Meyer, A.B.; Meyer, H.; Meyer, J.; Mikocki, S.; Morozov, A.; Müller, K.; Naumann, Th.; Newman, P.R.; Niebuhr, C.; Nowak, G.; Olsson, J.E.; Ozerov, D.; Pascaud, C.; Patel, G.D.; Perez, E.; Petrukhin, A.; Picuric, I.; Pirumov, H.; Pitzl, D.; Plačakytė, R.; Pokorny, B.; Polifka, R.; Povh, B.; Radescu, V.; Raicevic, N.; Ravdandorj, T.; Reimer, P.; Rizvi, E.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Rotaru, M.; Rusakov, S.; Šálek, D.; Sankey, D.P.C.; Sauter, M.; Sauvan, E.; Schmitt, S.; Schoeffel, L.; Schöning, A.; Sefkow, F.; Shushkevich, S.; Soloviev, Y.; Sopicki, P.; South, D.; Spaskov, V.; Specka, A.; Steder, M.; Stella, B.; Straumann, U.; Sykora, T.; Thompson, P.D.; Traynor, D.; Truöl, P.; Tsakov, I.; Tseepeldorj, B.; Turnau, J.; Valkárová, A.; Vallée, C.; Van Mechelen, P.; Vazdik, Y.; Wegener, D.; Wünsch, E.; Žáček, J.; Zhang, Z.; Žlebčík, R.; Zohrabyan, H.; Zomer, F.

    2016-01-23

    A first measurement is presented of exclusive photoproduction of $\\rho^0$ mesons associated with leading neutrons at HERA. The data were taken with the H1 detector in the years $2006$ and $2007$ at a centre-of-mass energy of $\\sqrt{s}=319$ GeV and correspond to an integrated luminosity of $1.16$ pb$^{-1}$. The $\\rho^0$ mesons with transverse momenta $p_T0.35$, are detected in the Forward Neutron Calorimeter. The phase space of the measurement is defined by the photon virtuality $Q^2 < 2$ GeV$^2$, the total energy of the photon-proton system $20 < W_{\\gamma p} < 100$ GeV and the polar angle of the leading neutron $\\theta_n < 0.75$ mrad. The cross section of the reaction $\\gamma p \\to \\rho^0 n \\pi^+$ is measured as a function of several variables. The data are interpreted in terms of a double peripheral process, involving pion exchange at the proton vertex followed by elastic photoproduction of a $\\rho^0$ meson on the virtual pion. In the framework of one-pion-exchange dominance the elastic cross se...

  20. Testing quantum chromodynamics in electroproduction

    International Nuclear Information System (INIS)

    Brodsky, S.J.

    1987-05-01

    The exclusive channels in electroproduction are discussed. The study of color transparency, the formation zone, and other novel aspects of QCD by measuring exclusive reactions inside nuclear targets is covered. Diffractive electroproduction channels are discussed, and exclusive nuclear processes in QCD are examined. Non-additivity of nuclear structure functions (EMC effect) is also discussed, as well as jet coalescence in electroproduction

  1. An annular ionization detector for quasi-elastic and transfer reaction studies

    CERN Document Server

    Dinesh, B V; Nayak, B K; Biswas, D C; Saxena, A; Pant, L M; Sahu, P K; Choudhury, R K

    2000-01-01

    An annular ionization chamber detector has been developed to study quasi-elastic and transfer reactions in heavy-ion collisions at near-barrier and sub-barrier energies. The important feature of the detector is that it has a near 2 pi coverage in the azimuthal angle phi for the particles entering in the detector at a given theta direction. This feature makes the detector very useful for measurement of the differential cross-sections at backward angles with respect to the beam direction, involving low cross-section reaction channels. The split anode configuration of the detector makes it capable of both particle identification and energy measurement for heavy ions and fission fragments. The detector has been tested using heavy-ion beams from the 14 MV-pelletron accelerator at Mumbai. Results on quasi-elastic excitation function measurements and barrier distribution studies in many heavy-ion reactions using this detector setup are discussed.

  2. Quasi-elastic helium-atom scattering from surfaces: experiment and interpretation

    International Nuclear Information System (INIS)

    Jardine, A.P.; Ellis, J.; Allison, W.

    2002-01-01

    Diffusion of an adsorbate is affected both by the adiabatic potential energy surface in which the adsorbate moves and by the rate of thermal coupling between the adsorbate and substrate. In principle both factors are amenable to investigation through quasi-elastic broadening in the energy spread of a probing beam of helium atoms. This review provides a topical summary of both the quasi-elastic helium-atom scattering technique and the available data in relation to the determination of diffusion parameters. In particular, we discuss the activation barriers deduced from experiment and their relation to the adiabatic potential and the central role played by the friction parameter, using the CO/Cu(001) system as a case study. The main issues to emerge are the need for detailed molecular dynamics simulations in the interpretation of data and the desirability of significantly greater energy resolution in the experiments themselves. (author)

  3. A quasi-elastic neutron scattering and neutron spin-echo study of hydrogen bonded system

    Energy Technology Data Exchange (ETDEWEB)

    Branca, C.; Faraone, A.; Magazu, S.; Maisano, G.; Mangione, A

    2004-07-15

    This work reports neutron spin echo results on aqueous solutions of trehalose, a naturally occurring disaccharide of glucose, showing an extraordinary bioprotective effectiveness against dehydration and freezing. We collected data using the SPAN spectrometer (BENSC, Berlin) on trehalose aqueous solutions at different temperature values. The obtained findings are compared with quasi-elastic neutron scattering results in order to furnish new results on the dynamics of the trehalose/water system on the nano and picoseconds scale.

  4. Cluster folding-model for quasi-elastic scattering of 23Na from 208Pb

    International Nuclear Information System (INIS)

    Kabir, A.; Johnson, R.C.; Tostevin, M.H.

    1991-01-01

    A cluster model of 23 Na is used to calculate the 23 Na-target interaction potentials by folding the cluster wavefunction with the cluster-target interaction potentials. Coupled channels calculations are carried out for the quasi-elastic scattering of polarized 23 Na from 208 Pb at 170 MeV and compared with recent experiments. Qualitative agreement with experiment is obtained when the interaction is adjusted by a single overall normalization constant. (author)

  5. Cross section measurements for quasi-elastic neutrino-nucleus scattering with the MINOS near detector

    Energy Technology Data Exchange (ETDEWEB)

    Dorman, Mark Edward [Univ. College London, Bloomsbury (United Kingdom)

    2008-04-01

    The Main Injector Neutrino Oscillation Search (MINOS) is a long baseline neutrino oscillation experiment based at the Fermi National Accelerator Laboratory (FNAL) in Chicago, Illinois. MINOS measures neutrino interactions in two large iron-scintillator tracking/sampling calorimeters; the Near Detector on-site at FNAL and the Far Detector located in the Soudan mine in northern Minnesota. The Near Detector has recorded a large number of neutrino interactions and this high statistics dataset can be used to make precision measurements of neutrino interaction cross sections. The cross section for charged-current quasi-elastic scattering has been measured by a number of previous experiments and these measurements disagree by up to 30%. A method to select a quasi-elastic enriched sample of neutrino interactions in the MINOS Near Detector is presented and a procedure to fit the kinematic distributions of this sample and extract the quasi-elastic cross section is introduced. The accuracy and robustness of the fitting procedure is studied using mock data and finally results from fits to the MINOS Near Detector data are presented.

  6. Cross section measurements for quasi-elastic neutrino-nucleus scattering with the MINOS near detector

    International Nuclear Information System (INIS)

    Dorman, Mark Edward

    2008-01-01

    The Main Injector Neutrino Oscillation Search (MINOS) is a long baseline neutrino oscillation experiment based at the Fermi National Accelerator Laboratory (FNAL) in Chicago, Illinois. MINOS measures neutrino interactions in two large iron-scintillator tracking/sampling calorimeters; the Near Detector on-site at FNAL and the Far Detector located in the Soudan mine in northern Minnesota. The Near Detector has recorded a large number of neutrino interactions and this high statistics dataset can be used to make precision measurements of neutrino interaction cross sections. The cross section for charged-current quasi-elastic scattering has been measured by a number of previous experiments and these measurements disagree by up to 30%. A method to select a quasi-elastic enriched sample of neutrino interactions in the MINOS Near Detector is presented and a procedure to fit the kinematic distributions of this sample and extract the quasi-elastic cross section is introduced. The accuracy and robustness of the fitting procedure is studied using mock data and finally results from fits to the MINOS Near Detector data are presented

  7. Position calibration of silicon strip detector using quasi-elastic scattering of 16O+197Au

    International Nuclear Information System (INIS)

    Yan Wenqi; Hu Hailong; Zhang Gaolong

    2013-01-01

    Background: Elastic scattering is induced by weakly unstable nuclei. Generally, a good angular resolution for angular distribution of elastic scattering is needed. The silicon strip detector is often used for this kind of experiment. Purpose: In order to use silicon strip detector to study the elastic scattering of weakly unbound nuclei, it is important to get the information of its position calibration. It is well known that the elastic scattering of stable nuclei has a good angular distribution and many experimental data have been obtained. Methods: So the scattering of stable nuclei can be used to calibrate the position information of silicon strip detector. In this experiment, the positions of silicon strip detectors are calibrated using 101 MeV and 59 MeV 16 O scattering on the 197 Au target. Results: The quasi-elastic peaks can be observed in the silicon strip detectors and the counts of quasi-elastic 16 O can be obtained. The solid angles of the silicon strip detectors are calibrated by using alpha source which has three alpha energy values. The angular distribution of quasi-elastic scattering of 16 O+ 197 Au is obtained at these two energy values. Conclusions: The experimental data of angular distribution are reasonable and fit for the principle of angular distribution of elastic scattering. It is concluded that in the experiment these silicon strip detectors can accurately give the position information and can be used for the elastic scattering experiment. (authors)

  8. Quasi-elastic cross sections for 1GeV proton incident on {sup 4}He and {sup 12}C

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, M.; Nakamoto, T.; Shigyo, N. [Kyushu Univ., Fukuoka (Japan). Faculty of Engineering] [and others

    1997-03-01

    The experiment of p-n quasi-elastic scattering cross sections was carried out for 1GeV protons on {sup 4}He and {sup 12}C. The coincident measurement was made at c.m. angles of {+-} 90deg. The experiment was simulated by the use of HETC (High Energy Transport Code). It was examined to apply the p-n quasi-elastic scattering cross sections to neutron flux measurement. (author)

  9. A study of quasi-elastic muon (anti)neutrino scattering in he NOMAD experiment

    International Nuclear Information System (INIS)

    Lyubushkin, Vladimir

    2009-01-01

    We have studied the muon neutrino and antineutrino quasi-elastic (QEL) scattering reactions (v μ n→μ - p and v-bar μ p→μ + n using a set of experimental data collected by the NOMAD collaboration. We have performed measurements of the cross-section of these processes on a nuclear target (mainly Carbon) normalizing it to the total v μ (v-bar μ ) charged current cross-section. The results for the flux averaged QEL cross-sections in the (anti)neutrino energy interval 3-100 GeV are qel >v μ = (0.92±0.02(stat)±0.06(syst))x10 -38 cm 2 and qel >v-bar μ = (0.81±0.05(stat)±0.09(syst))x10 -38 cm 2 for neutrino and antineutrino, respectively. The axial mass parameter MA was extracted from the measured quasi-elastic neutrino cross-section. The corresponding result is M A = 1.05±0.02(stat)±0.06(syst) GeV. It is consistent with the axial mass values recalculated from the antineutrino cross-section and extracted from the pure Q 2 shape analysis of the high purity sample of v μ quasi-elastic 2-track events, but has smaller systematic error and should be quoted as the main result of this work. Our measured MA is found to be in good agreement with the world average value obtained in previous deuterium filled bubble chamber experiments. The NOMAD measurement of M A is lower than those recently published by K2K and MiniBooNE collaborations. However, within the large errors quoted by these experiments on M A , these results are compatible with the more precise NOMAD value.

  10. A study of quasi-elastic muon (anti) neutrino scattering in the NOMAD experiment

    International Nuclear Information System (INIS)

    Lyubushkin, V.V.; Popov, B.A.

    2008-01-01

    We have studied the muon neutrino and antineutrino-quasi-elastic (QEL) scattering reactions (ν μ n → μ - p and νbar μ p → μ + n) using a set of experimental data collected by the NOMAD collaboration. We have performed measurements of the cross section of these processes on a nuclear target (mainly carbon) normalizing it to the total ν μ (νbar μ ) charged current cross section. The results for the flux averaged QEL cross sections in the (anti)neutrino energy interval 3-100 GeV are (σ qel )ν μ = (0.92 ± 0.02 (stat.) ± 0.06 (syst.)) · 10 -38 cm 2 and (σ qel )νbar μ = (0.81 ± 0.05 (stat.) ± 0.08 (syst.)) · 10 -38 cm 2 for neutrino and antineutrino, respectively. The axial mass parameter M A was extracted from the measured quasi-elastic neutrino cross section. The corresponding result is M A = 1.05 ± 0.02 (stat.) ± 0.06 (syst.) GeV. It is consistent with the axial mass values recalculated from the antineutrino cross section and extracted from the pure Q 2 shape analysis of the high purity sample of ν μ quasi-elastic 2-track events, but has smaller systematic error and should be quoted as the main result of this work. The measured M A is found to be in good agreement with the world average value obtained in the previous deuterium filled bubble chamber experiments. These results do not support M A measurements published recently by the K2K and MiniBooNE collaborations, which reported somewhat larger values, which are however compatible with our results within their large errors

  11. High-energy elastic and quasi-elastic deuteron-nucleus scattering

    International Nuclear Information System (INIS)

    Tekou, Amouzou

    1974-01-01

    A study is made of deuteron-nucleus elastic and quasi-elastic scattering and the connection between the opaque nucleus model and the Glauber model is pointed out. The contributions to different cross-sections of the collisions in which the nucleus, excited by one of the nucleons of the deuteron, is brought back to the ground state by the other nucleon is analysed. Coherent deuteron disintegration is found to be highly improbable when the target nucleus is heavy and incoherent disintegration accounts for nearly all the deuteron disintegration. Thus a correct comparison between theoretical and experimental data on proton stripping must take the incoherent deuteron disintegration into consideration

  12. Quasi-elastic Scattering Measurements in the 6,7Li+144Sm Systems

    International Nuclear Information System (INIS)

    Capurro, O. A.; Arazi, A.; Fernandez Niello, J. O.; Figueira, J. M.; Marti, G. V.; Martinez Heimann, D.; Negri, A. E.; Pacheco, A. J.; Monteiro, D. S.; Otomar, D. R.; Gomes, P. R. S.; Guimaraes, V.

    2009-01-01

    In the present work, results of measurements of quasi-elastic scattering cross sections using a silicon-telescope detector at backward angles are reported. They allowed us to deduce fusion barrier distributions from the first derivative of the corresponding excitation function (-d(dσ qes /dσ Rut )/dE). We report data for the systems 6,7 Li on 144 Sm which are characterized by loosely bound projectiles onto a closed neutron shell target. The experimental excitation functions and the associated barrier distributions are compared for both systems.

  13. Analysis of the Quasi-Elastic Scattering of Neutrons in Hydrogenous Liquids

    International Nuclear Information System (INIS)

    Porohit, S.N.

    1966-11-01

    A critical discussion of the quasi-elastic scattering of neutrons by incoherent (hydrogenous) liquids is presented. Using the line shape expression a comparative discussion of several phenomenological models has been carried out. Extension of the Singwi-Sjoelander zero phonon expression, for the jump-diffusion model, so as to include the one phonon expression has also been given. For a delayed diffusion model a complete treatment of S(K, ω) is presented. Along the lines of the macroscopic diffusion cooling, a microscopic diffusion cooling effect in fluids is speculated

  14. Quasi-elastic high-pressure waves in 2024 Al and Cu

    International Nuclear Information System (INIS)

    Morris, C.E.; Fritz, J.N.; Holian, B.L.

    1981-01-01

    Release waves from the back of a plate slap experiment are used to estimate the longitudinal modulus, bulk modulus and shear strength of the metal in the state produced by a symmetric collision. The velocity of the interface between the metal target and a window material is measured by the axially symmetric magnetic (ASM) probe. Wave profiles for initial states up to 90 GPa for 2024 Al and up to 150 GPa for Cu have been obtained. Elastic perfectly-plastic (EPP) theory cannot account for the results. A relatively simple quasi-elastic plastic (QEP) model can

  15. Analysis of the Quasi-Elastic Scattering of Neutrons in Hydrogenous Liquids

    Energy Technology Data Exchange (ETDEWEB)

    Porohit, S N [Nuclear Science and Engineering Dept., Rensselaer Polytechnique Inst., Troy, NY (United States)

    1966-11-15

    A critical discussion of the quasi-elastic scattering of neutrons by incoherent (hydrogenous) liquids is presented. Using the line shape expression a comparative discussion of several phenomenological models has been carried out. Extension of the Singwi-Sjoelander zero phonon expression, for the jump-diffusion model, so as to include the one phonon expression has also been given. For a delayed diffusion model a complete treatment of S(K, {omega}) is presented. Along the lines of the macroscopic diffusion cooling, a microscopic diffusion cooling effect in fluids is speculated.

  16. Ion conducting behavior in secondary battery materials detected by quasi-elastic neutron scattering measurements

    International Nuclear Information System (INIS)

    Nozaki, Hiroshi

    2014-01-01

    Ionic conducting behaviors in secondary battery materials, i.e. cathode and solid electrolyte, were studied with quasi-elastic neutron scattering (QENS) measurements. Although the incoherent scattering length for Li and Na is lower by two orders of magnitude than that for H, the QENS spectra were clearly detected using the combination of an intense neutron source and a low background spectrometer. The fundamental parameters, such as, the activation energy, the jump distance, and the diffusion coefficient were obtained by analyzing QENS spectra. These parameters are consistent with the previous results estimated by muon-spin relaxation (μSR) measurements and first principles calculations. (author)

  17. Short Range Correlations in Nuclei at Large xbj through Inclusive Quasi-Elastic Electron Scattering

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Zhihong [Univ. of Virginia, Charlottesville, VA (United States)

    2013-12-01

    The experiment, E08-014, in Hall-A at Jefferson Lab aims to study the short-range correlations (SRC) which are necessary to explain the nuclear strength absent in the mean field theory. The cross sections for 2H, 3He, 4He, 12C, 40Ca and 48Ca, were measured via inclusive quasi-elastic electron scattering from these nuclei in a Q2 range between 0.8 and 2.8 (GeV/c)2 for x>1. The cross section ratios of heavy nuclei to 2H were extracted to study two-nucleon SRC for 1

  18. Excitation functions for quasi-elastic transfer reactions induced with heavy ions in bismuth

    International Nuclear Information System (INIS)

    Gardes, D.; Bimbot, R.; Maison, J.; Reilhac, L. de; Rivet, M.F.; Fleury, A.; Hubert, F.; Llabador, Y.

    1977-01-01

    The excitation functions for the production of 210 Bi, 210 Po, sup(207-211)At and 211 Rn through quasi-elastic transfer reactions induced with heavy ions in 209 Bi have been measured. The corresponding reactions involved the transfer of one neutron, one proton, two and three charges from projectile to target. The projectiles used were 12 C, 14 N, 16 O, 19 F, 20 Ne, 40 Ca, 56 Fe and 63 Cu. The experimental techniques involved target irradiations and off-line α and γ activity measurements. Chemical separations were used to solve specific problems. Careful measurements of incident energies and cross sections were performed close to the reaction thresholds

  19. π0, rho0 ω0 production in high energy neutrino and antineutrino interactions

    International Nuclear Information System (INIS)

    Velasco, J.

    1980-09-01

    The work presented in this thesis is concerned with the hadronic shower in the neutrino and antineutrino interactions of the high energy charged-current type. The π 0 particles issued from this hadronic shower are analysed and the rho 0 and ω 0 production rate are determined in view to try to understand the quark fragmentation process, that is to say the QCD theory relative to the quark confinement problem. The experimental device is described in the chapter II. Chapter III is dealing with the analysis of the exposures obtained with this device, together with the incident neutrino energy determination methods and a general description of the final data characteristics. The π 0 production is studied from the decay γ observed in the bubble chamber. The existing different methods are analyzed and compared with the used one. The π 0 properties are studied in detail. In chapter 5, the rho 0 and ω 0 resonance production rate is calculated, using the previous chapter results. Finally, chapter 6 summarizes the thesis conclusions [fr

  20. Analysis of Quasi-Elastic e-n and e-p Scattering from Deuterium

    Science.gov (United States)

    Balsamo, Alexander; Gilfoyle, Gerard; CLAS12 Collaboration

    2017-09-01

    One of Jefferson Lab's goals is to unravel the quark-gluon structure of nuclei. We will use the ratio, R, of electron-neutron to electron-proton scattering on deuterium to probe the magnetic form factor of the neutron. We have developed an end-to-end analysis from simulation to extraction of R in quasi-elastic kinematics for an approved experiment with the CLAS12 detector. We focus on neutrons detected in the CLAS12 calorimeters and protons measured with the CLAS12 forward detector. Events were generated with the Quasi-Elastic Event Generator (QUEEG) and passed through the Monte Carlo code gemc to simulate the CLAS12 response. These simulated events were reconstructed using the latest CLAS12 Common Tools. We first match the solid angle for e-n and e-p events. The electron information is used to predict the path of both a neutron and proton through CLAS12. If both particles interact in CLAS12 the e-n and e-p events have the same solid angle. We select QE events by searching for nuclei near the predicted position. An angular cut between the predicted 3-momentum of the nucleon and the measured value, θpq, separates QE and inelastic events. We will show the simulated R as a function of the four-momentum transfer Q2. Work supported by the University of Richmond and the US Department of Energy.

  1. Quasi-elastic (QENS) and inelastic neutron scattering (INS) on hexamethylbenzene

    Energy Technology Data Exchange (ETDEWEB)

    Krawczyk, J. [H. Niewodniczanski Institute of Nuclear Physics PAN, NZ3, ul. Radzikowskiego 152, 31-342 Cracow (Poland)]. E-mail: jan.krawczyk@ifj.edu.pl; Mayer, J. [H. Niewodniczanski Institute of Nuclear Physics PAN, NZ3, ul. Radzikowskiego 152, 31-342 Cracow (Poland); Natkaniec, I. [H. Niewodniczanski Institute of Nuclear Physics PAN, NZ3, ul. Radzikowskiego 152, 31-342 Cracow (Poland): Frank Laboratory of Neutron Physics, JINR, 141980 Dubna, Russia (Russian Federation); Nowina Konopka, M. [H. Niewodniczanski Institute of Nuclear Physics PAN, NZ3, ul. Radzikowskiego 152, 31-342 Cracow (Poland); Pawlukojc [Frank Laboratory of Neutron Physics, JINR, 141980 Dubna, Russia (RU): Institute of Nuclear Chemistry and Technology, 03-195 Warszawa (Poland); Steinsvoll, O. [Institute for Energy Technology, 2007 Kjeller (Norway); Janik, J.A. [H. Niewodniczanski Institute of Nuclear Physics PAN, NZ3, ul. Radzikowskiego 152, 31-342 Cracow (Poland)

    2005-05-15

    The Quasi-elastic Neutron scattering (QENS) spectra of polycrystalline hexamethylbenzene (HMB) were measured for temperatures from 10K to room temperature (phase III and phase II) for momentum transfer 1.9A{sup -1}. The Inelastic Neutron scattering (INS) and QENS spectra for momentum transfer 0.5-2.9A{sup -1} were measured at T=20, 100 and 130K for energy transfer up to 200meV. The low-resolution diffraction patterns, used as the phase indicator, were also obtained. In the phase III (below 117K), we see practically no quasi-elastic broadening. In phase II, the broadening changes with the temperature are in good agreement with the Arrhenius law. The estimated activation barrier to reorientation is 6kJ/mol. The fitted mean time between instantaneous 120{sup o} jumps of CH{sub 3} groups changes from 10{sup -11}s at T=130K to 2x10{sup -13}s at room temperature. On the basis of EISF versus momentum transfer dependency it is hardly possible to decide what is the geometry of the reorientation. Both reorientation of the CH{sub 3} groups around the three-fold symmetry axis and reorientation of the whole molecule around the six-fold symmetry axis of the benzene ring could describe our results, the former being more probable. The measured INS spectra are compared with the quantum chemical ab initio calculations performed for an isolated HMB molecule.

  2. Quasi-elastic (QENS) and inelastic neutron scattering (INS) on hexamethylbenzene

    International Nuclear Information System (INIS)

    Krawczyk, J.; Mayer, J.; Natkaniec, I.; Nowina Konopka, M.; Pawlukojc; Steinsvoll, O.; Janik, J.A.

    2005-01-01

    The Quasi-elastic Neutron scattering (QENS) spectra of polycrystalline hexamethylbenzene (HMB) were measured for temperatures from 10K to room temperature (phase III and phase II) for momentum transfer 1.9A -1 . The Inelastic Neutron scattering (INS) and QENS spectra for momentum transfer 0.5-2.9A -1 were measured at T=20, 100 and 130K for energy transfer up to 200meV. The low-resolution diffraction patterns, used as the phase indicator, were also obtained. In the phase III (below 117K), we see practically no quasi-elastic broadening. In phase II, the broadening changes with the temperature are in good agreement with the Arrhenius law. The estimated activation barrier to reorientation is 6kJ/mol. The fitted mean time between instantaneous 120 o jumps of CH 3 groups changes from 10 -11 s at T=130K to 2x10 -13 s at room temperature. On the basis of EISF versus momentum transfer dependency it is hardly possible to decide what is the geometry of the reorientation. Both reorientation of the CH 3 groups around the three-fold symmetry axis and reorientation of the whole molecule around the six-fold symmetry axis of the benzene ring could describe our results, the former being more probable. The measured INS spectra are compared with the quantum chemical ab initio calculations performed for an isolated HMB molecule

  3. Derivation of capture and reaction cross sections from experimental quasi-elastic and elastic backscattering probabilities

    International Nuclear Information System (INIS)

    Sargsyan, V.V.; Adamian, G.G.; Antonenko, N.V.; Gomes, P.R.S.

    2014-01-01

    We suggest simple and useful methods to extract reaction and capture (fusion) cross sections from the experimental elastic and quasi-elastic backscattering data.The direct measurement of the reaction or capture (fusion) cross section is a difficult task since it would require the measurement of individual cross sections of many reaction channels, and most of them could be reached only by specific experiments. This would require different experimental setups not always available at the same laboratory and, consequently, such direct measurements would demand a large amount of beam time and would take probably some years to be reached. Because of that, the measurements of elastic scattering angular distributions that cover full angular ranges and optical model analysis have been used for the determination of reaction cross sections. This traditional method consists in deriving the parameters of the complex optical potentials which fit the experimental elastic scattering angular distributions and then of deriving the reaction cross sections predicted by these potentials. Even so, both the experimental part and the analysis of this latter method are not so simple. In the present work we present a much simpler method to determine reaction and capture (fusion) cross sections. It consists of measuring only elastic or quasi-elastic scattering at one backward angle, and from that, the extraction of the reaction or capture cross sections can easily be performed. (author)

  4. Quasi-elastic scattering of electrons from 40Ca at high momentum transfer

    International Nuclear Information System (INIS)

    Yates, T.C.

    1992-01-01

    Previous quasi-elastic electron scattering experiments have yielded seemingly inconsistent results when the integrated longitudinal strength is compared to calculations using the relativistic fermi gas model. Measurements made at Saclay on 12 C, 40 Ca, 48 Ca, 56 Fe, and 208 Pb indicated a smaller integrated longitudinal strength than expected on the basis of the relativistic fermi gas model. However, 238 U data taken at Bates showed nearly the full expected longitudinal strength at a momentum transfer of 550 MeV/c. This is one of the outstanding discrepancies in nuclear physics. Earlier experiments were hampered in that high momentum transfer could not be obtained at forward angles where the longtudinal strength is a large fraction of the total strength. The present experiment was designed to take advantage of the higher energy capability (greater than 800 MeV) at Bates recirculated linac in order to obtain momentum transfers greater than 600 MeV/c at a scattering angle of 45.5 degrees. Under these conditions the longitudinal strength is 40-75% of the total quasi-elastic strength

  5. Analysing power for quasi-elastic pp scattering in carbon and for elastic pp scattering on free protons

    International Nuclear Information System (INIS)

    Bystricky, J.; Deregel, J.; Lehar, F.

    1984-01-01

    The ratio of the analysing powers for quasi-elastic pp scattering in carbon and for elastic scattering on free protons was measured from T = 0.52 to 2.8 GeV by scattering of the SATURNE II polarized proton beam on carbon and CH 2 . It was found to have a maximum at about 0.8 GeV. The energy dependence for quasi-elastic scattering on carbon had not been measured before above 1 GeV. The observed effect was not expected from simple models

  6. Interpretation of the quasi-elastic neutron scattering on PAA by rotational diffusion models

    International Nuclear Information System (INIS)

    Bata, L.; Vizi, J.; Kugler, S.

    1974-10-01

    First the most important data determined by other methods for para azoxy anisolon (PAA) are collected. This molecule makes a rotational oscillational motion around the mean molecular direction. The details of this motion can be determined by inelastic neutron scattering. Quasielastic neutron scattering measurements were carried out without orienting magnetic field on a time-of-flight facility with neutron beam of 4.26 meV. For the interpretation of the results two models, the spherical rotation diffusion model and the circular random walk model are investigated. The comparison shows that the circular random walk model (with N=8 sites, d=4A diameter and K=10 10 s -1 rate constant) fits very well with the quasi-elastic neutron scattering, while the spherical rotational diffusion model seems to be incorrect. (Sz.N.Z.)

  7. Search for neutrino oscillations in the MINOS experiment by using quasi-elastic interactions

    Energy Technology Data Exchange (ETDEWEB)

    Piteira, Rodolphe [Univ. Pierre et Marie Curie, Paris (France)

    2005-09-29

    The enthusiasm of the scientific community for studying oscillations of neutrinos is equaled only by the mass of their detectors. The MINOS experiment determines and compares the near spectrum of muonic neutrinos from the NUMI beam to the far one, in order to measure two oscillation parameters: Δm$2\\atop{23}$ and sin2 (2θ23). The spectra are obtained by analyzing the charged current interactions which difficulty lies in identifying the interactions products (e.g. muons). An alternative method identifying the traces of muons, bent by the magnetic field of the detectors, and determining their energies is presented in this manuscript. The sensitivity of the detectors is optimal for the quasi-elastic interactions, for which a selection method is proposed, to study their oscillation. Even though it reduces the statistics, such a study introduces fewer systematic errors, constituting the ideal method on the long range.

  8. Broadband Dielectric Spectroscopy and Quasi-Elastic Neutron Scattering on Single-Ion Polymer Conductors

    Science.gov (United States)

    Soles, Christopher; Peng, Hua-Gen; Page, Kirt; Snyder, Chad; Pandy, Ashoutosh; Jeong, Youmi; Runt, James; NIST Collaboration; Pennsylvania Collaboration

    2011-03-01

    The application of solid polymer electrolytes in rechargeable batteries has not been fully realized after decades of research due to its low conductivity. Dramatic increases of the ion conductivity are needed and this progress requires the understanding of conduction mechanism. We address this topic in two fronts, namely, the effect of plasticizer additives and geometric confinement on the charge transfer mechanism. To this end, we combine broadband dielectric spectroscopy (BDS) to characterize the ion mobility and quasi-elastic neutron scattering (QENS) to quantify segmental motion on a single-ion model polymer electrolyte. Deuterated small molecules were used as plasticizers so that the segmental motion of the polymer electrolyte could be monitored by QENS to understand the mechanism behind the increased conductivity. Anodic aluminum oxide (AAO) membranes with well defined channel sizes are used as the matrix to study the transport of ions solvated in a 1D polymer electrolyte.

  9. Measurement of the parity violation in quasi-elastic electroweak electron-scattering from 9Be

    International Nuclear Information System (INIS)

    Achenbach, W.; Andresen, H.G.

    1987-01-01

    Measurement of the Parity Violation in Quasi-Elastic Electroweak Electron-Scattering from 9 Be in the energy range of about 300 MeV is fulfilled. The measurement of the parity violating asymmetry is obtained by a comparison of scattering for a + helicity beam to that for a - helicity beams. To permit a meaningful comparison required that the + helicity and the - helicity beams being identical in all other respects. Measurements at different energies and targets (hydrogen, deuterium) in the medium energy region will allow to determine α, β, γ, δ in a model-independent way. Regarding future experiments at the Mainz microtron cw accelerator, coincidence experiments will open new experimental possibilities for large solid angle detector systems

  10. Quasi-elastic neutron scattering studies of the diffusion of hydrogen in metals

    Energy Technology Data Exchange (ETDEWEB)

    Ross, D K [Birmingham Univ. (UK). School of Physics and Space Research

    1989-01-01

    Quasi-elastic neutron scattering provides a uniquely detailed way of investigating microscopic models for diffusion in lattice gases. In the present paper we discuss extensions of the original Chudley-Elliott model to cover systems containing high concentrations of interacting particles for both the incoherent and coherent cases. In the former case, the peak width is changed by site blocking and by interactions and its shape is altered by correlation effects between successive jumps. In the coherent case, although interactions introduce different correlation effects, the most important changes are due to the short-range order caused by the interactions. A simple Mean Field theory is described which predicts peak narrowing where the diffuse scattering is at a maximum. Experimental tests of both coherent and incoherent theories are described for the case of {alpha}'NbD{sub x}. (orig.).

  11. Quasi-elastic neutron scattering studies of the diffusion of hydrogen in metals

    International Nuclear Information System (INIS)

    Ross, D.K.

    1989-01-01

    Quasi-elastic neutron scattering provides a uniquely detailed way of investigating microscopic models for diffusion in lattice gases. In the present paper we discuss extensions of the original Chudley-Elliott model to cover systems containing high concentrations of interacting particles for both the incoherent and coherent cases. In the former case, the peak width is changed by site blocking and by interactions and its shape is altered by correlation effects between successive jumps. In the coherent case, although interactions introduce different correlation effects, the most important changes are due to the short-range order caused by the interactions. A simple Mean Field theory is described which predicts peak narrowing where the diffuse scattering is at a maximum. Experimental tests of both coherent and incoherent theories are described for the case of α'NbD x . (orig.)

  12. mQfit, a new program for analyzing quasi-elastic neutron scattering data

    Directory of Open Access Journals (Sweden)

    Martinez Nicolas

    2015-01-01

    Full Text Available Analysis of Quasi-elastic Neutron Scattering (QENS data of complex systems such as biological or soft matter samples in a comprehensive and explicit way often requires great efforts. Most popular software only allows to fit spectra originating from one single instrument and does not permit to extract parameters from a model that is fitted simultaneously to data taken at different instrumental resolutions. We present here a new program, mQfit (multiple QENS dataset fitting, that enables to fit QENS data taken at different spectrometers (with typical resolutions between 0.01 and 0.1 meV and momentum transfer ranges. This allows drastically reducing the number of fitting parameters. The routine is implemented with a user friendly Graphical User's Interface (GUI, and freely available. As an example, we will present results obtained on E. coli bacterial pellets, and compare them to values published in the literature.

  13. Mode coupling analysis of coherent quasi-elastic neutron scattering from fluorite-type materials approaching the superionic transition

    International Nuclear Information System (INIS)

    Chaturvedi, D.K.; Tosi, M.P.

    1987-08-01

    Neutron scattering experiments on SrCl 2 , CaF 2 and PbF 2 have shown that intensity and width of the coherent diffuse quasi-elastic spectrum increase rapidly with temperature into the fast-ion conducting phase, the main feature in the integrated quasi-elastic intensity being a peak just beyond the (200) point along the (100) direction in scattering wave vector space. The Zwanzig-Mori memory function formalism is used in this work to analyze the quasi-elastic scattering cross section from charge density fluctuations in terms of anharmonic couplings between the vibrational modes of the crystal. The two- and three-mode channels are examined for compatibility with the quasi-elastic neutron scattering evidence, on the basis of (i) energy and momentum conservation and van Hove singularity arguments and (ii) measured phonon dispersion curves along the main symmetry directions in SrCl 2 , CaF 2 , SrF 2 and BaF 2 . The analysis identifies a specific microscopic role for the Raman-active optic branches. The eigenvectors of the relevant Raman-active and partner modes in the three-mode channel describe relative displacements of the two halogens in the unit cell superposed on relative displacements of the halogen and alkaline earth components. This microscopic picture is thus consistent with the superionic transition being associated with the onset of dynamic disorder in the anionic component of the crystal. (author). 13 refs, 2 tabs

  14. Polarized coincidence electroproduction

    International Nuclear Information System (INIS)

    Heimann, R.L.

    1975-03-01

    A study is made of the inclusive electroproduction of single hadrons off a polarized target. Bjorken scaling laws and the hadron azimuthal distribution are derived from the quark parton model. The polarization asymmetries scale when the target spin is along the direction of the virtual photon, and (apart from significant exception) vanish for transverse spin. These results have a simple explanation; emphasis is given both to the general mathematical formalism and to intuitive physical reasoning. Through this framework other cases are considered: quarks with anomalous magnetic moment; renormalization group effects and asymptotic freedom; production of vector mesons (whose spin state is analysed by their decay); relation to large transverse momentum hadron production; and a covariant parton model calculation. Spin 0 partons and Regge singularities are also considered. All of these cases (apart from the last two) modify the pattern of conclusions. Vector meson production shows polarization enhancements in the density matrix element rhosub(0+); the renormalization group approach does not lead to any significant suppressions. They are also less severe in parton models for large Psub(T) hadrons, and are not supported by the covariantly formulated calculation. The origins of these differences are isolated and used to exemplify the sensitivity polarized hadron electroproduction has to delicate detail that is otherwise concealed. (author)

  15. A sub-GeV charged-current quasi-elastic $\

    Energy Technology Data Exchange (ETDEWEB)

    Walding, Joseph James [Imperial College, London (United Kingdom)

    2009-12-01

    Neutrino-nucleus charged-current quasi-elastic scattering is the signal interaction used by many neutrino oscillation experiments. For muon disappearance studies the signal mode is νμn → μp. Modern oscillation experiments, such as T2K, produce neutrino beams with peak beam energies of order a few-GeV. It is therefore vitally important to have accurate measurements of the charged-current quasi-elastic crosssection for future neutrino oscillation experiments. Neutrino-nucleus cross-sections in the few-GeV region are not well understood, with the main uncertainties coming from understanding of the neutrino beam flux and the final state interactions within nuclei. SciBooNE is a sub-GeV neutrino-nucleus cross-section experiment based at Fermilab, Batavia, USA, with the goal to measure neutrino cross-sections with precision of order 5%. SciBooNE took data from June 2007 until August 2008, in total 0.99×1020 and 1.53×1020 protons on target were collected in neutrino and anti-neutrino mode, respectively. In this thesis a νμ charged-current quasi-elastic (CCQE) cross-section contained within the SciBar sub-detector is presented. A method to tag muons in SciBar was developed and three samples were isolated. An excess in backwards tracks in the one-track sample is observed. A Poisson maximum likelihood is used to extract the CCQE cross-section. The fit was applied using a basic fit parameter model, successfully used to obtain the cross-section in the SciBar-MRD matched CCQE analysis. This method was found to be insufficient in describing the data for the SciBarcontained CCQE analysis. By adding two migration parameters the cross-section was calculated to be 1.004 ± 0.031 (stat)+0.101 -0.150(sys) × 10-38 cm2/neutron, excluding backwards tracks with a χ2 = 203.8/76 d.o.f. and 1.083 ± 0.030(stat)+0.115 -0.177(sys) × 10-38 cm2

  16. MODELING OF RAILWAY TRACK OPERATION AS A SYSTEM OF QUASI-ELASTIC ORTHOTROPIC LAYERS

    Directory of Open Access Journals (Sweden)

    Sychev Vyacheslav Petrovich

    2016-03-01

    Full Text Available In this paper the authors give a solution to the problem of the impact of a rolling stock on the rail track on the basis of modeling a railway track as a multi-layered space, introducing each of the layers is a quasi-elastic orthotropic layer with cylindrical anisotropy in the polar coordinate system. The article describes wave equations, taking into account the rotational inertia of cross sectional and transverse shear strains. From the point of view of classical structural mechanics train path can be represented as a multilayer system comprising separate layers with different stiffness, lying on the foundation being the elastic-isotropic space. Winkler model provides that the basis is linearly deformable space, there are loads influencing its surface. These loads are transferred through a layered deformable half-space. This representation is used in this study as an initial approximation. For more accurate results of the deformation of a railway track because of rolling dynamic loads it is proposed to present a railway track in the form of a layered structure, where each element (assembled rails and sleepers, ballast section, the soil in the embankment, basement soils is modeled as a planar quasi-elastic orthotropic layer with cylindrical anisotropy. The equations describing the dynamic behaviour of flat element in a polar coordinate system are hyperbolic in nature and take into account the rotational inertia of the cross sectional and the transverse shear strains. This allows identifying the impact on the final characteristics of the blade wave effects, and oscillatory processes. In order to determine the unknown functions included in the constitutive equations it is proposed to use decomposition in power series in spatial coordinate and time. In order to determine the coefficients of ray series for the required functions, it is necessary to differentiate the defining wave equations k times on time, to take their difference on the different

  17. Heterodyne quasi-elastic light-scattering instrument for biomedical diagnostics.

    Science.gov (United States)

    Lebedev, A D; Ivanova, M A; Lomakin, A V; Noskin, V A

    1997-10-20

    The heterodyne technique has a number of advantages over the homodyne technique when an accurate characterization of particle-size distribution (PSD) of heterogeneous systems is required. However, there are problems related to acoustic vibrations that make it difficult to take advantage of the heterodyne technique. An instrument developed for quasi-elastic light scattering (QELS) that uses the optical heterodyning principle is described. Vibration-related problems are considerably reduced because of the incorporation of all optical elements into one solid optical block. A real-time correlation analysis of the photocurrent fluctuations is performed by a PC-embedded analog-to-digital converter card with a digital signal processor. Investigation of the PSD in biological fluids for medical diagnostics is presented as a typical application. A diagnostic analysis of the PSD requires a simultaneous processing of a huge number of QELS data. An original statistical algorithm to accomplish this analysis has been developed. Technical specifications of instrumentation for heterodyne QELS measurement are discussed.

  18. Quasi-elastic neutron scattering studies of the slow dynamics of supercooled and glassy aspirin

    International Nuclear Information System (INIS)

    Zhang Yang; Mamontov, Eugene; Tyagi, Madhusudan; Chen, Sow-Hsin

    2012-01-01

    Aspirin, also known as acetylsalicylic acid (ASA), is not only a wonderful drug, but also a good glass former. Therefore, it serves as an important molecular system to study the near-arrest and arrested phenomena. In this paper, a high-resolution quasi-elastic neutron scattering (QENS) technique is used to investigate the slow dynamics of supercooled liquid and glassy aspirin from 410 down to 350 K. The measured QENS spectra can be analyzed with a stretched exponential model. We find that (i) the stretched exponent β(Q) is independent of the wavevector transfer Q in the measured Q range and (ii) the structural relaxation time τ(Q) follows a power-law dependence on Q. Consequently, the Q-independent structural relaxation time τ 0 can be extracted for each temperature to characterize the slow dynamics of aspirin. The temperature dependence of τ 0 can be fitted with the mode-coupling power law, the Vogel-Fulcher-Tammann equation and a universal equation for fragile glass forming liquids recently proposed by Tokuyama in the measured temperature range. The calculated dynamic response function χ T (Q, t) using the experimentally determined self-intermediate scattering function of the hydrogen atoms of aspirin shows direct evidence of the enhanced dynamic fluctuations as the aspirin is increasingly supercooled, in agreement with the fixed-time mean squared displacement (x 2 ) and the non-Gaussian parameter α 2 extracted from the elastic scattering.

  19. Quasi-Elastic Neutron Scattering Studies of the Slow Dynamics of Supercooled and Glassy Aspirin

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yang [ORNL; Tyagi, M. [NCNR and University of Maryland; Mamontov, Eugene [ORNL; Chen, Sow-hsin H [ORNL

    2011-01-01

    Aspirin, also known as acetylsalicylic acid (ASA), is not only a wonderful drug, but also a good glass former. Therefore, it serves as an important molecular system to study the near-arrest and arrested phenomena. In this paper, a high-resolution quasi-elastic neutron scattering (QENS) technique is used to investigate the slow dynamics of supercooled liquid and glassy aspirin from 410 K down to 350 K. The measured QENS spectra can be analyzed with a stretched exponential model. We find that (i) the stretched exponent (Q) is independent of the wave vector transfer Q in the measured Q-range, and (ii) the structural relaxation time (Q) follows a power law dependence on Q. Consequently, the Q-independent structural relaxation time 0 can be extracted for each temperature to characterize the slow dynamics of aspirin. The temperature dependence of 0 can be fitted with the mode coupling power law, the Vogel-Fulcher-Tammann equation and a universal equation for fragile glass forming liquids recently proposed by M. Tokuyama in the measured temperature range. The calculated dynamic response function T(Q,t) using the experimentally determined self-intermediate scattering function of the hydrogen atoms of aspirin shows a direct evidence of the enhanced dynamic fluctuations as the aspirin is increasingly supercooled, in agreement with the fixed-time mean squared displacement x2 and non-Gaussian parameter 2 extracted from the elastic scattering.

  20. Application of quasi-elastic neutron scattering to dynamics study of confined water

    International Nuclear Information System (INIS)

    Li Hua; Zhang Lili; Yi Zhou

    2014-01-01

    Background: Quasi-elastic neutron scattering (QENS) is an important experiment for dynamics study of confined water. It is significant to study the dynamics of confined water in cement paste. Purpose: In this paper, we have two aims. One is to present a reviewer of QENS study on dynamics of confined water in cement paste in recent years. The other is to illustrate the QENS application to the study on dynamics of confined water based on cement paste. Method: Relaxing cage model (RCM) is specially introduced for the analyses of QENS spectra. Results: Based on RCM, several parameters for describing the dynamics of confined water in cement paste, can be obtained from the analyses of QENS spectra: a fraction of mobile 'glassy' water molecules embedded in amorphous gel region surrounding the hydration products, 1-p, the capture time of confined water molecule in some place-τ 0 , the average translational relaxation time-<τ>, the self-diffusion coefficient-D, and a phenomenological shape parameter describing the uniform of amorphous in cement paste-β. Conclusion: All these provide a practical method for QENS study on dynamics of confined water in cement paste. (authors)

  1. Quasi-elastic neutron scattering studies of the slow dynamics of supercooled and glassy aspirin

    Science.gov (United States)

    Zhang, Yang; Tyagi, Madhusudan; Mamontov, Eugene; Chen, Sow-Hsin

    2012-02-01

    Aspirin, also known as acetylsalicylic acid (ASA), is not only a wonderful drug, but also a good glass former. Therefore, it serves as an important molecular system to study the near-arrest and arrested phenomena. In this paper, a high-resolution quasi-elastic neutron scattering (QENS) technique is used to investigate the slow dynamics of supercooled liquid and glassy aspirin from 410 down to 350 K. The measured QENS spectra can be analyzed with a stretched exponential model. We find that (i) the stretched exponent β(Q) is independent of the wavevector transfer Q in the measured Q range and (ii) the structural relaxation time τ(Q) follows a power-law dependence on Q. Consequently, the Q-independent structural relaxation time τ0 can be extracted for each temperature to characterize the slow dynamics of aspirin. The temperature dependence of τ0 can be fitted with the mode-coupling power law, the Vogel-Fulcher-Tammann equation and a universal equation for fragile glass forming liquids recently proposed by Tokuyama in the measured temperature range. The calculated dynamic response function χT(Q, t) using the experimentally determined self-intermediate scattering function of the hydrogen atoms of aspirin shows direct evidence of the enhanced dynamic fluctuations as the aspirin is increasingly supercooled, in agreement with the fixed-time mean squared displacement langx2rang and the non-Gaussian parameter α2 extracted from the elastic scattering.

  2. The Measurement of Neutrino Induced Quasi-Elastic Cross Section In NOMAD

    CERN Document Server

    Kim, Jae Jun

    2010-01-01

    NOMAD (Neutrino Oscillation MAgnetic Detector) was a short baseline neutrino experiment conducted at CERN (the European Laboratory for Particle physics) West Area Neutrino Facility (WANF) with a neutrino beam provided by the super proton synchrotron (SPS) accelerator. In this dissertation, we present a measurement of muon-neutrino induced quasi-elastic cross section and its axial-mass off an isoscalar target in the NOMAD detector. The incident neutrino energy in NOMAD experiment spans from 2.5 to 300 GeV. The measurement of cross-section is conducted in two seperate kinematic-based topology, two-track and one-track topologies, where a proton is not properly reconstructed. The QEL cross-section as a function of the incoming neutrino energy is consistent for the two different topologies, and within errors , constant as a function of the neutrino energy. We determine the energy-averaged cross-section. From the shape-comparisons of kinematics of QEL-like events, the parameter of QEL axial mass is estimated. It i...

  3. Dynamics of water and ions in clays of type montmorillonite by microscopic simulation and quasi-elastic neutron scattering

    International Nuclear Information System (INIS)

    Malikova, N.

    2005-09-01

    Montmorillonite clays in low hydration states, with Na + and Cs + compensating counter ions, are investigated by a combination of microscopic simulation and quasi-elastic neutron scattering to obtain information on the local structure and dynamics of water and ions in the interlayer. At first predictions of simulation into the dynamics of water and ions at elevate temperatures are shown (0 deg C 80 deg C, pertinent for the radioactive waste disposal scenario) Marked difference is observed between the modes of diffusion of the Na + and C + counter ions. In water dynamics, a significant step towards bulk water behaviour is seen on transition from the mono- to bilayer states. Secondly, a detailed comparison between simulation and quasi-elastic neutron scattering (Neutron Spin Echo and Time-of-Flight) regarding ambient temperature water dynamics is presented. Overall, the approaches are found to be in good agreement with each other and limitations of each of the methods are clearly shown. (author)

  4. Recent advances and open questions in neutrino-induced quasi-elastic scattering and single photon production

    Energy Technology Data Exchange (ETDEWEB)

    Garvey, G.T., E-mail: garvey@lanl.gov [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545 (United States); Harris, D.A., E-mail: dharris@fnal.gov [Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL, 60510-5011 (United States); Tanaka, H.A., E-mail: tanaka@phas.ubc.ca [Institute of Particle Physics and Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Tayloe, R., E-mail: rtayloe@indiana.edu [Department of Physics, Indiana University, 727 E. Third St., Bloomington, IN 47405-7105 (United States); Zeller, G.P., E-mail: gzeller@fnal.gov [Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL, 60510-5011 (United States)

    2015-06-15

    The study of neutrino–nucleus interactions has recently seen rapid development with a new generation of accelerator-based neutrino experiments employing medium and heavy nuclear targets for the study of neutrino oscillations. A few unexpected results in the study of quasi-elastic scattering and single photon production have spurred a revisiting of the underlying nuclear physics and connections to electron–nucleus scattering. A thorough understanding and resolution of these issues is essential for future progress in the study of neutrino oscillations. A recent workshop hosted by the Institute of Nuclear Theory at the University of Washington (INT-13-54W) examined experimental and theoretical developments in neutrino–nucleus interactions and related measurements from electron and pion scattering. We summarize the discussions at the workshop pertaining to the aforementioned issues in quasi-elastic scattering and single photon production, particularly where there was consensus on the highest priority issues to be resolved and the path towards resolving them.

  5. Neutron quasi-elastic scattering study of translational motions in the smectic H, C and A phases of TBBA

    International Nuclear Information System (INIS)

    Dianoux, A.J.; Volino, F.; Heidemann, A.; Hervet, H.

    1975-01-01

    Neutron quasi-elastic scattering experiments in the smectic H, C and A phases of TBBA are presented, using the high resolution backscattering technique. The data are analyzed in terms of translational motion and are characterized by an apparent self diffusion coefficient Dsub(ap). The physical meaning of Dsub(ap) is discussed in terms of the true bulk self diffusion tensor and other kinds of translational motions [fr

  6. Quasi-elastic scattering an alternative tool for mapping the fusion barriers for heavy-ion induced fusion reaction

    International Nuclear Information System (INIS)

    Behera, B.R.

    2016-01-01

    Heavy element synthesis through heavy-ion induced fusion reaction is an active field in contemporary nuclear physics. Exact knowledge of fusion barrier is one of the essential parameters for planning any experiments for heavy element production. Theoretically there are many models available to predict the exact barrier. Though these models are successful for predicting the fusion of medium mass nuclei, it somehow fails for predicting the exact location of barrier for fusion of heavy nuclei. Experimental determination of barrier for such reactions is required for future experiments for the synthesis of heavy elements. Traditionally fusion barrier is determined taking a double derivative of fusion excitation function. However, such method is difficult in case of fusion of heavy nuclei due to its very low fusion/capture cross section and its experimental complications. Alternatively fusion barrier can be determined by measuring the quasi-elastic cross section at backward angles. This method can be applied for determining the fusion barrier for the fusion of heavy nuclei. Experimental determination of fusion barrier by different methods and comparison of the fusion excitation function and quasi-elastic scattering methods for the determination of fusion barrier are reviewed. At IUAC, New Delhi recently a program has been started for the measurement of fusion barrier through quasi-elastic scattering methods. The experimental facility and the first results of the experiments carried out with this facility are presented. (author)

  7. Sensitivity of fusion and quasi-elastic barrier distributions of {sub 16}O+{sub 144}Sm reaction on the coupling radius parameter

    Energy Technology Data Exchange (ETDEWEB)

    Zamrun, Muhammad; Usman, Ida; Variani, Viska Inda [Department of Physics, Haluoleo University, Kendari, Sulawesi Tengagra, 93232 (Indonesia); Kassim, Hasan Abu [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2014-03-05

    We study the heavy-ion collision at sub-barrier energies of {sub 16}O+{sub 144}Sm system using full order coupled-channels formalism. We especially investigate the sensitivity of fusion and quasi-elastic barrier distributions for this system on the coupling radius parameter. We found that the coupled-channels calculations of the fusion and the quasi-elastic barrier distributions are sensitive to the coupling radius for this reaction in contrast to the fusion and quasi-elastic cross section. Our study indicates that the larger coupling radius, i.e., r{sub coup}=1.20, is required by the experimental quasi-elastic barrier distribution. However, the experimental fusion barrier distribution compulsory the small value, i.e., r{sub coup}=1.06.

  8. Inclusive production of $\\rho^{0}(770), f_0(980)$ and $f_2(1270)$ mesons in $\

    CERN Document Server

    Astier, P.; Baldisseri, A.; Baldo-Ceolin, M.; Banner, M.; Bassompierre, G.; Benslama, K.; Besson, N.; Bird, I.; Blumenfeld, Barry J.; Bobisut, F.; Bouchez, J.; Boyd, S.; Bueno, A.; Bunyatov, S.; Camilleri, L.; Cardini, A.; Cattaneo, P.W.; Cavasinni, V.; Cervera-Villanueva, A.; Collazuol, G.; Conforto, G.; Conta, C.; Contalbrigo, M.; Cousins, R.; Daniels, D.; Degaudenzi, H.; Del Prete, T.; De Santo, Antonella; Dignan, T.; Di Lella, L.; do Couto e Silva, E.; Dumarchez, J.; Ellis, Malcolm; Fazio, T.; Feldman, G.J.; Ferrari, R.; Ferrere, D.; Flaminio, V.; Fraternali, M.; Gaillard, J.M.; Gangler, E.; Geppert, D.; Gibin, D.; Gninenko, S.; Godley, A.; Gomez-Cadenas, J.J.; Gosset, J.; Gossling, C.; Gouanere, M.; Grant, A.; Graziani, G.; Guglielmi, A.; Hagner, C.; Hernando, J.; Hubbard, D.; Hurst, P.; Hyett, N.; Iacopini, E.; Joseph, C.; Juget, F.; Kirsanov, M.; Klimov, O.; Kokkonen, J.; Kovzelev, A.; Krasnoperov, A.; Kuznetsov, V.; Lacaprara, S.; Lachaud, C.; Lakic, B.; Lanza, A.; La Rotonda, L.; Laveder, M.; Letessier-Selvon, A.; Levy, J.M.; Linssen, L.; Ljubicic, A.; Long, J.; Lupi, A.; Marchionni, A.; Martelli, F.; Mechain, X.; Mendiburu, J.P.; Meyer, J.P.; Mezzetto, M.; Mishra, S.R.; Moorhead, G.F.; Naumov, D.; Nedelec, P.; Nefedov, Yu.; Nguyen-Mau, C.; Orestano, D.; Pastore, F.; Peak, L.S.; Pennacchio, E.; Pessard, H.; Petti, R.; Placci, A.; Polesello, G.; Pollmann, D.; Polyarush, A.; Popov, B.; Poulsen, C.; Rathouit, P.; Rico, J.; Roda, C.; Rubbia, A.; Salvatore, F.; Schahmaneche, K.; Schmidt, B.; Sevior, M.; Sillou, D.; Soler, F.J.P.; Sozzi, G.; Steele, D.; Stiegler, U.; Stipcevic, M.; Stolarczyk, T.; Tareb-Reyes, M.; Taylor, G.N.; Tereshchenko, V.; Toropin, A.; Touchard, A.M.; Tovey, S.N.; Tran, M.T.; Tsesmelis, E.; Ulrichs, J.; Vacavant, L.; Valdata-Nappi, M.; Valuev, V.; Vannucci, F.; Varvell, K.E.; Veltri, M.; Vercesi, V.; Vidal-Sitjes, G.; Vieira, J.M.; Vinogradova, T.; Weber, F.V.; Weisse, T.; Wilson, F.F.; Winton, L.J.; Yabsley, Bruce D.; Zaccone, H.; Zuber, K.; Zuccon, P.

    2001-01-01

    The inclusive production of the meson resonances $\\rho^{0}(770)$, $f_0(980)$ and $f_2(1270)$ in neutrino-nucleus charged current interactions has been studied with the NOMAD detector exposed to the wide band neutrino beam generated by 450 GeV protons at the CERN SPS. For the first time the $f_{0}(980)$ meson is observed in neutrino interactions. The statistical significance of its observation is 6 standard deviations. The presence of $f_{2}(1270)$ in neutrino interactions is reliably established. The average multiplicity of these three resonances is measured as a function of several kinematic variables. The experimental results are compared to the multiplicities obtained from a simulation based on the Lund model. In addition, the average multiplicity of $\\rho^{0}(770)$ in antineutrino - nucleus interactions is measured.

  9. Quantum numbers of the $X(3872)$ state and orbital angular momentum in its $\\rho^0 J/\\psi$ decays

    CERN Document Server

    Aaij, Roel; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; d'Argent, Philippe; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Bird, Thomas; Birnkraut, Alex; Bizzeti, Andrea; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Brett, David; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casanova Mohr, Raimon; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cavallero, Giovanni; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pieter; Davis, Adam; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Silva, Weeraddana; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Di Ruscio, Francesco; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dufour, Laurent; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farinelli, Chiara; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forty, Roger; Francisco, Oscar; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garofoli, Justin; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gastaldi, Ugo; Gauld, Rhorry; Gavardi, Laura; Gazzoni, Giulio; Geraci, Angelo; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianelle, Alessio; Gianì, Sebastiana; Gibson, Valerie; Giubega, Lavinia-Helena; Gligorov, V.V.; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Hampson, Thomas; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; Hernando Morata, Jose Angel; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Humair, Thibaud; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kelsey, Matthew; Kenyon, Ian; Kenzie, Matthew; Ketel, Tjeerd; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Korolev, Mikhail; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kurek, Krzysztof; Kvaratskheliya, Tengiz; La Thi, Viet Nga; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lambert, Robert W; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Lohn, Stefan; Longstaff, Iain; Lopes, Jose; Lowdon, Peter; Lucchesi, Donatella; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Machefert, Frederic; Maciuc, Florin; Maev, Oleg; Maguire, Kevin; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Märki, Raphael; Marks, Jörg; Martellotti, Giuseppe; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathad, Abhijit; Mathe, Zoltan; Matteuzzi, Clara; Mauri, Andrea; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; Meadows, Brian; Meier, Frank; Meissner, Marco; Merk, Marcel; Milanes, Diego Alejandro; Minard, Marie-Noelle; Mitzel, Dominik Stefan; Molina Rodriguez, Josue; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Janine; Müller, Katharina; Müller, Vanessa; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Ninci, Daniele; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Osorio Rodrigues, Bruno; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Aranzazu; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parkes, Christopher; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Petridis, Konstantinos; Petrolini, Alessandro; Petruzzo, Marco; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Playfer, Stephen; Plo Casasus, Maximo; Poikela, Tuomas; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Rachwal, Bartolomiej; Rademacker, Jonas; Rakotomiaramanana, Barinjaka; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz, Hugo; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santimaria, Marco; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmelzer, Timon; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sepp, Indrek; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Silva Coutinho, Rafael; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skillicorn, Ian; Skwarnicki, Tomasz; Smith, Edmund; Smith, Eluned; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Steinkamp, Olaf; Stenyakin, Oleg; Sterpka, Christopher Francis; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Stroili, Roberto; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szczypka, Paul; Szumlak, Tomasz; T'Jampens, Stephane; Tekampe, Tobias; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Todd, Jacob; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Trabelsi, Karim; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Weiden, Andreas; Whitehead, Mark; Wiedner, Dirk; Wilkinson, Guy; Wilkinson, Michael; Williams, Mark Richard James; Williams, Matthew; Williams, Mike; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang

    2015-07-30

    Angular correlations in $B^+\\to X(3872) K^+$ decays, with $X(3872)\\to \\rho^0 J/\\psi$, $\\rho^0\\to\\pi^+\\pi^-$ and $J/\\psi \\to\\mu^+\\mu^-$, are used to measure orbital angular momentum contributions and to determine the $J^{PC}$ value of the $X(3872)$ meson. The data correspond to an integrated luminosity of 3.0 fb$^{-1}$ of proton-proton collisions collected with the LHCb detector. This determination, for the first time performed without assuming a value for the orbital angular momentum, confirms the quantum numbers to be $J^{PC}=1^{++}$. The $X(3872)$ is found to decay predominantly through S wave and an upper limit of $4\\%$ at $95\\%$ C.L. is set on the fraction of D wave.

  10. Hard electroproduction of hybrid mesons

    International Nuclear Information System (INIS)

    Anikin, I.V.; LPT Universite Paris-Sud, Orsay; Szymanowski, L.; Teryaev, O.V.; ); Wallon, S.

    2005-01-01

    We estimate the sizeable cross section for deep exclusive electroproduction of an exotic J PC = 1 -+ hybrid meson in the Bjorken regime. The production amplitude scales like the one for usual meson electroproduction, i.e. as 1/Q 2 . This is due to the non-vanishing leading twist distribution amplitude for the hybrid meson, which may be normalized thanks to its relation to the energy momentum tensor and to the QCD sum rules technique. The hard amplitude is considered up to next-to-leading order in as and we explore the consequences of fixing the renormalization scale ambiguity through the BLM procedure. (author)

  11. Anti-Neutrino Charged Current Quasi-Elastic Scattering in MINER$\

    Energy Technology Data Exchange (ETDEWEB)

    Chvojka, Jesse John [Univ. of Rochester, NY (United States)

    2012-01-01

    The phenomenon of neutrino oscillation is becoming increasingly understood with results from accelerator-based and reactor-based experiments, but unanswered questions remain. The proper ordering of the neutrino mass eigenstates that compose the neutrino avor eigenstates is not completely known. We have yet to detect CP violation in neutrino mixing, which if present could help explain the asymmetry between matter and anti-matter in the universe. We also have not resolved whether sterile neutrinos, which do not interact in any Standard Model interaction, exist. Accelerator-based experiments appear to be the most promising candidates for resolving these questions; however, the ability of present and future experiments to provide answers is likely to be limited by systematic errors. A significant source of this systematic error comes from limitations in our knowledge of neutrino-nucleus interactions. Errors on cross-sections for such interactions are large, existing data is sometimes contradictory, and knowledge of nuclear effects is incomplete. One type of neutrino interaction of particular interest is charged current quasi-elastic (CCQE) scattering, which yields a final state consisting of a charged lepton and nucleon. This process, which is the dominant interaction near energies of 1 GeV, is of great utility to neutrino oscillation experiments since the incoming neutrino energy and the square of the momentum transferred to the final state nucleon, Q2, can be reconstructed using the final state lepton kinematics. To address the uncertainty in our knowledge of neutrino interactions, many experiments have begun making dedicated measurements. In particular, the MINER A experiment is studying neutrino-nucleus interactions in the few GeV region. MINERvA is a fine-grained, high precision, high statistics neutrino scattering experiment that will greatly improve our understanding of neutrino cross-sections and nuclear effects that affect the final state particles

  12. Weak transitions in the quasi-elastic reaction 12C(e,e'p)11B

    International Nuclear Information System (INIS)

    Steenhoven, G. van der; Blok, H.P.; Vrije Univ., Amsterdam; Jans, E.; Lapikas, L.; Quint, E.N.M.; Witt Huberts, P.K.A. de

    1988-01-01

    In a high-resolution quasi-elastic 12 C(e,e'p) 11 B experiment several weak transitions have been observed to excited final states with spin and parity characteristic of direct knockout from orbitals above the 1p shell. The momentum distributions, which have been measured in parallel kinematics at an outgoing-proton energy of 70 MeV in the range of missing momentum - 170 ≤ p m ≤ 210 MeV/c, show the shape expected for a single-step knockout process. It is demonstrated that the interference between a direct-knockout process and a two-step process leading to the same final state in the (e,e'p) reaction may cause important modifications of the deduced spectroscopic factors. Explicit coupled-channels (CC) calculations show that the spectroscopic factor for the transition to the 7 - /2 state at 6.743 MeV is reduced by a factor of 6, whereas the spectroscopic factors of the other weak transitions observed in the present experiment are uncertain by a factor of 2 due to CC-effects. Since the strength of these transitions is larger than can be explained by a pure two-step process, we interpret the observation of these transitions as direct evidence for the existence of ground-state correlations in 12 C. The total spectroscopic strength in the E x region between 6 and 12 MeV amounts to 0.1, or 4.1% of the observed strength for 1p knockout in the low E x region. Two peaks have been identified in the missing-energy spectrum that hitherto have not been reported: A narrow peak at E x =9.82 (3) MeV with an l=0 character and a broad structure centered at about 11.5 MeV with an l=1 character. The missing-energy spectrum between E x =12 and 24 MeV corresponding to 1s 1/2 knockout has also been analyzed. The deduced momentum distribution shows evidence for the onset of a two-nucleon mechanism beyond the two-particle emission threshold. (orig.)

  13. Electroproduction at large momentum transfers

    International Nuclear Information System (INIS)

    van Bibber, K.

    1991-03-01

    The possibilities of electroproduction experiments at a facility such as the proposed European electron accelerator are discussed. Examples given are from studies of hadronization, color transparency, backward production, virtual Compton scattering and target spectator decay. Some conclusions about machine parameters are drawn. 25 refs., 15 figs

  14. Deep electroproduction of exotic hybrid mesons

    International Nuclear Information System (INIS)

    Anikin, I.V.; Pire, B.; Szymanowski, L.; Teryaev, O.V.; Wallon, S.

    2004-01-01

    We evaluate the leading order amplitude for the deep exclusive electroproduction of an exotic hybrid meson in the Bjorken regime. We show that, contrarily to naive expectation, this amplitude factorizes at the twist 2 level and thus scales like usual meson electroproduction when the virtual photon and the hybrid meson are longitudinally polarized. Exotic hybrid mesons may thus be studied in electroproduction experiments at JLAB, HERA (HERMES) or CERN (Compass)

  15. Morphology, surface roughness, electron inelastic and quasi-elastic scattering in elastic peak electron spectroscopy of polymers

    International Nuclear Information System (INIS)

    Lesiak, B.; Kosinski, A.; Nowakowski, R.; Koever, L.; Toth, J.; Varga, D.; Cserny, I.; Sulyok, A.; Gergely, G.

    2006-01-01

    Complete text of publication follows. Elastic peak electron spectroscopy (EPES) deals with the interaction of electrons with atoms of a solid surface, studying the distribution of electrons backscattered elastically. The nearest vicinity of the elastic peak, (low kinetic energy region) reflects both, electron inelastic and quasi-elastic processes. The incident electrons produce surface excitations, inducing surface plasmons with the corresponding loss peaks separated by 1 - 20 eV energy from the elastic peak. Quasi-elastic losses result from the recoil of scattering atoms of different atomic number, Z. The respective energy shift and Doppler broadening of the elastic peak depend on Z, the primary electron energy, E, and the measurement geometry. Quantitative surface analytical application of EPES, such as determination of parameters describing electron transport, requires a comparison of experimental data with corresponding data derived from Monte Carlo (MC) simulation. Several problems occur in EPES studies of polymers. The intensity of elastic peak, considered in quantitative surface analysis, is influenced by both, the inelastic and quasi-elastic scattering processes (especially for hydrogen scattering atoms and primary electron energy above 1000 eV). An additional factor affecting the elastic peak intensity is the surface morphology and roughness. The present work compares the effect of these factors on the elastic peak intensity for selected polymers (polyethylene, polyaniline and polythiophenes). X-ray photoelectron spectroscopy (XPS) and helium pycnometry are applied for deriving the surface atomic composition and the bulk density, while scanning electron microscopy (SEM) and atomic force microscopy (AFM) for determining surface morphology and roughness. According to presented results, the influence of surface morphology and roughness is larger than those of surface excitations or recoil of hydrogen atoms. The component due to recoil of hydrogen atoms can be

  16. Breakup coupling effects on near-barrier quasi-elastic scattering of 6,7Li on 144Sm

    International Nuclear Information System (INIS)

    Otomar, D. R.; Lubian, J.; Gomes, P. R. S.; Monteiro, D. S.; Capurro, O. A.; Arazi, A.; Figueira, J. M.; Marti, G. V.; Heimann, D. Martinez; Negri, A. E.; Pacheco, A. J.; Niello, J. O. Fernandez; Guimaraes, V.; Chamon, L. C.

    2009-01-01

    Excitation functions of quasi-elastic scattering at backward angles have been measured for the 6,7 Li+ 144 Sm systems at near-barrier energies, and fusion barrier distributions have been extracted from the first derivatives of the experimental cross sections with respect to the bombarding energies. The data have been analyzed in the framework of continuum discretized coupled-channel calculations, and the results have been obtained in terms of the influence exerted by the inclusion of different reaction channels, with emphasis on the role played by the projectile breakup.

  17. Recent Advances and Open Questions in Neutrino-induced Quasi-elastic Scattering and Single Photon Production

    Energy Technology Data Exchange (ETDEWEB)

    Garvey, G. T. [Los Alamos; Harris, D. A. [Fermilab; Tanaka, H. A. [British Columbia U.; Tayloe, R. [Indiana U.; Zeller, G. P. [Fermilab

    2015-06-15

    The study of neutrino–nucleus interactions has recently seen rapid development with a new generation of accelerator-based neutrino experiments employing medium and heavy nuclear targets for the study of neutrino oscillations. A few unexpected results in the study of quasi-elastic scattering and single photon production have spurred a revisiting of the underlying nuclear physics and connections to electron–nucleus scattering. A thorough understanding and resolution of these issues is essential for future progress in the study of neutrino oscillations.

  18. Microscopic dynamics of the hydrogen bonded systems studied by quasi-elastic slow neutron scattering

    International Nuclear Information System (INIS)

    Padureanu, I.; Aranghel, D.; Radulescu, A.; Ion, M.; Lechner, R. E.; Desmedt, A.; Pieper, J.

    2002-01-01

    provide a satisfactory description of supercooled liquid dynamics. In order to contribute to an answer, we performed a new experiment of incoherent slow neutron scattering. Part of the obtained results is presented in a previously paper. Neutron scattering experiments were done at the time of flight spectrometer NEAT of the Berlin Neutron Scattering Center(BENSC). In this study we have used cold neutrons with the wavelength of λ = 5.1 A, which corresponds to an incident energy E o = 3.145 meV and a resolution ΔE = 98 μeV (full width at half-maximum, FWHM, of the elastic line of the vanadium sample). The scattering spectra were taken with 140 detectors in a large angular range 15.41 angle -1 for the elastic wave and the energy transfer hω s (θ,ω). The final data are obtained at 27 scattering angles as a function of the energy transfer hω for 8 temperatures 50 K, 100 K, 150 K, 188 K, 240 K, 290 K, 320 K and 400 K. The data have been also analyzed in terms of the generalized frequency distribution g (ω), the angular distribution dσ/dΩ of the quasi-elastically scattered neutrons and the observed line width ΔE = f (Q 0 2 , T). An obvious feature attribute to as boson peak is present at all temperatures from 50 K to 290 K in the dynamic scattering function Ss (θ,ω) and the generalized frequency distribution g (ω)/ω 2 of glycerol. The temperature dependence of the peak position shows an anomalous behavior near T g . This effect proves a soft dynamics additionally to the acoustic modes. At the same time the temperature dependence of the FWHM of the quasielastic line leads to a possible two step process approach in glycerol. (authors)

  19. Static and quasi-elastic small angle neutron scattering on biocompatible ionic ferrofluids: magnetic and hydrodynamic interactions

    CERN Document Server

    Gazeau, F; Dubois, E; Perzynski, R

    2003-01-01

    We investigate the structure and dynamics of ionic magnetic fluids (MFs), based on ferrite nanoparticles, dispersed at pH approx 7 either in H sub 2 O or in D sub 2 O. Polarized and non-polarized static small angle neutron scattering (SANS) experiments in zero magnetic field allow us to study both the magnetic and the nuclear contributions to the neutron scattering. The magnetic interparticle attraction is probed separately from the global thermodynamic repulsion and compares well to direct magnetic susceptibility measurements. The magnetic interparticle correlation is in these fluid samples independent of the probed spatial scale. In contrast, a spatial dependence of the interparticle correlation is evidenced at large PHI by the nuclear structure factor. A model of magnetic interaction quantitatively explains the under-field anisotropy of the SANS nuclear contribution. In a quasi-elastic neutron spin-echo experiment, we probe the Brownian dynamics of translation of the nanoparticles in the range 1.3 sup<=...

  20. Analysis of different multiplicities and their interference in quasi-elastic cluster knock-out by fast hadrons

    International Nuclear Information System (INIS)

    Golovanova, N.F.; Ibraeva, E.T.; Neudatchin, V.G.

    1978-01-01

    Different multiplicities and their interference in hadron scattering have been investigated on the basis of a new dynamic approach to quasi-elastic knock-out of nucleon clusters by fast hadrons from light nuclei. It is shown that in the region of momentum transfer values p, where scattering multiplicities less than b are predominant, the effective numbers and form factors determined in Refs. 1) -- 3) no longer act as pure structural nuclear factors (b means the number of nucleons in the knocked-out cluster). These characteristics are significantly dependent on the process dynamics. Only in the region of values p, where the maximum hadron scattering multiplicity b is realized, the effective numbers and form factors do assume the purely structural meaning. (auth.)

  1. Quasi-elastic interactions and one-pion production by neutrinos and anti-neutrinos on a deuterium target

    International Nuclear Information System (INIS)

    Barlag, S.J.M.

    1984-01-01

    In this thesis, the weak charged current interactions of neutrinos and antineutrinos with nucleons are described, in which the neutrino scatters in a quasi-elastic way with the nucleon, leaving an excited nucleon state. The experiments have been performed in the bubble chamber BEBC, filled with deuterium and exposed to the CERN Wide Band (anti-)neutrino beams. This gave the opportunity to study both interactions on protons and on neutrons separately, whereas the measurement of the exclusive channels could be performed with a high precision. After a short introduction of the relevant theories (standard model; QCD; one-pion production models; FKR quark model), the experimental set-up at CERN is described as well as the bubble chamber picture facility in Amsterdam. Next, results of the neutrino and antineutrino experiments are given followed by a comparison with theory. (Auth.)

  2. Experimental study of the fusion dynamics of 32,34S + 197Au with quasi-elastic scattering

    International Nuclear Information System (INIS)

    Schuck, T.J.; Dasgupta, M.; Timmers, H.

    2000-01-01

    Full text: The fusion dynamics of heavy systems, such as 64 Ni + 208 Pb, leading to the synthesis of super-heavy elements is presently not fully understood. Typical beam energies in such reactions are of the order or smaller than the Coulomb barrier height to minimize the excitation energy of the compound system and increase the survival probability of evaporation residues. It is known that at such energies the relative motion of projectile and target couples to internal degrees of freedom of the system, such as collective motion and particle transfer. This can give rise to a distribution of fusion barriers, which generally leads to an enhancement of the fusion cross-section below the Coulomb barrier. The important role of the individual degrees of freedom can be identified by extracting representations of the barrier distribution from fusion excitation functions. Complementary representations can be obtained from measurements of the quasi-elastic or elastic scattering excitation functions at backward angles. The sensitivity of the representations from scattering is limited to the lower energy part of the barrier distribution, which, however, may contain important signatures of positive Q-value neutron transfer channels. Neutron transfer may be a precursor of neutron flow and neck-formation, which are considered in macroscopic models of the fusion of heavy systems. In order to study the influence of neutron transfer in heavy fusion reactions, quasielastic scattering has been measured for 32 , 34 S + 197 Au at energies spanning the Coulomb barrier. The quasi-elastic yield, including inelastic and transfer reactions, was detected at 165 deg with a Si-surface barrier detector. The excitation functions have been normalized to Rutherford scattering, detected at 30 deg using an existing gas ionisation detector. Representations of the barrier distributions have been extracted and are compared with earlier measurements for 32 S + 208 Pb

  3. Exclusive electroproduction of pion pairs

    International Nuclear Information System (INIS)

    Warkentin, N.; Schaefer, A.; Diehl, M.; Ivanov, D. Yu.

    2007-01-01

    We investigate electroproduction of pion pairs on the nucleon in the framework of QCD factorization for hard exclusive processes. We extend previous analyses by taking the hard-scattering coefficients at next-to-leading order in α s . The dynamics of the produced pion pair is described by two-pion distribution amplitudes, for which we perform a detailed theoretical and phenomenological analysis. In particular, we obtain constraints on these quantities by comparing our results with measurements of angular observables that are sensitive to the interference between two-pion production in the isoscalar and isovector channels. (orig.)

  4. Coherent $\\rho^0$ photoproduction in ultra-peripheral Pb-Pb collisions at $\\mathbf{\\sqrt{\\textit{s}_{\\rm NN}}} = 2.76$ TeV

    CERN Document Server

    Adam, Jaroslav; Aggarwal, Madan Mohan; Aglieri Rinella, Gianluca; Agnello, Michelangelo; Agrawal, Neelima; Ahammed, Zubayer; Ahn, Sang Un; Aimo, Ilaria; Aiola, Salvatore; Ajaz, Muhammad; Akindinov, Alexander; Alam, Sk Noor; Aleksandrov, Dmitry; Alessandro, Bruno; Alexandre, Didier; Alfaro Molina, Jose Ruben; Alici, Andrea; Alkin, Anton; Alme, Johan; Alt, Torsten; Altinpinar, Sedat; Altsybeev, Igor; Alves Garcia Prado, Caio; Andrei, Cristian; Andronic, Anton; Anguelov, Venelin; Anielski, Jonas; Anticic, Tome; Antinori, Federico; Antonioli, Pietro; Aphecetche, Laurent Bernard; Appelshaeuser, Harald; Arcelli, Silvia; Armesto Perez, Nestor; Arnaldi, Roberta; Aronsson, Tomas; Arsene, Ionut Cristian; Arslandok, Mesut; Augustinus, Andre; Averbeck, Ralf Peter; Azmi, Mohd Danish; Bach, Matthias Jakob; Badala, Angela; Baek, Yong Wook; Bagnasco, Stefano; Bailhache, Raphaelle Marie; Bala, Renu; Baldisseri, Alberto; Baltasar Dos Santos Pedrosa, Fernando; Baral, Rama Chandra; Barbano, Anastasia Maria; Barbera, Roberto; Barile, Francesco; Barnafoldi, Gergely Gabor; Barnby, Lee Stuart; Ramillien Barret, Valerie; Bartalini, Paolo; Barth, Klaus; Bartke, Jerzy Gustaw; Bartsch, Esther; Basile, Maurizio; Bastid, Nicole; Basu, Sumit; Bathen, Bastian; Batigne, Guillaume; Batista Camejo, Arianna; Batyunya, Boris; Batzing, Paul Christoph; Bearden, Ian Gardner; Beck, Hans; Bedda, Cristina; Behera, Nirbhay Kumar; Belikov, Iouri; Bellini, Francesca; Bello Martinez, Hector; Bellwied, Rene; Belmont Iii, Ronald John; Belmont Moreno, Ernesto; Belyaev, Vladimir; Bencedi, Gyula; Beole, Stefania; Berceanu, Ionela; Bercuci, Alexandru; Berdnikov, Yaroslav; Berenyi, Daniel; Bertens, Redmer Alexander; Berzano, Dario; Betev, Latchezar; Bhasin, Anju; Bhat, Inayat Rasool; Bhati, Ashok Kumar; Bhattacharjee, Buddhadeb; Bhom, Jihyun; Bianchi, Livio; Bianchi, Nicola; Bianchin, Chiara; Bielcik, Jaroslav; Bielcikova, Jana; Bilandzic, Ante; Biswas, Rathijit; Biswas, Saikat; Bjelogrlic, Sandro; Blanco, Fernando; Blau, Dmitry; Blume, Christoph; Bock, Friederike; Bogdanov, Alexey; Boggild, Hans; Boldizsar, Laszlo; Bombara, Marek; Book, Julian Heinz; Borel, Herve; Borissov, Alexander; Borri, Marcello; Bossu, Francesco; Botje, Michiel; Botta, Elena; Boettger, Stefan; Braun-Munzinger, Peter; Bregant, Marco; Breitner, Timo Gunther; Broker, Theo Alexander; Browning, Tyler Allen; Broz, Michal; Brucken, Erik Jens; Bruna, Elena; Bruno, Giuseppe Eugenio; Budnikov, Dmitry; Buesching, Henner; Bufalino, Stefania; Buncic, Predrag; Busch, Oliver; Buthelezi, Edith Zinhle; Buxton, Jesse Thomas; Caffarri, Davide; Cai, Xu; Caines, Helen Louise; Calero Diaz, Liliet; Caliva, Alberto; Calvo Villar, Ernesto; Camerini, Paolo; Carena, Francesco; Carena, Wisla; Castillo Castellanos, Javier Ernesto; Castro, Andrew John; Casula, Ester Anna Rita; Cavicchioli, Costanza; Ceballos Sanchez, Cesar; Cepila, Jan; Cerello, Piergiorgio; Chang, Beomsu; Chapeland, Sylvain; Chartier, Marielle; Charvet, Jean-Luc Fernand; Chattopadhyay, Subhasis; Chattopadhyay, Sukalyan; Chelnokov, Volodymyr; Cherney, Michael Gerard; Cheshkov, Cvetan Valeriev; Cheynis, Brigitte; Chibante Barroso, Vasco Miguel; Dobrigkeit Chinellato, David; Chochula, Peter; Choi, Kyungeon; Chojnacki, Marek; Choudhury, Subikash; Christakoglou, Panagiotis; Christensen, Christian Holm; Christiansen, Peter; Chujo, Tatsuya; Chung, Suh-Urk; Zhang, Chunhui; Cicalo, Corrado; Cifarelli, Luisa; Cindolo, Federico; Cleymans, Jean Willy Andre; Colamaria, Fabio Filippo; Colella, Domenico; Collu, Alberto; Colocci, Manuel; Conesa Balbastre, Gustavo; Conesa Del Valle, Zaida; Connors, Megan Elizabeth; Contreras Nuno, Jesus Guillermo; Cormier, Thomas Michael; Corrales Morales, Yasser; Cortes Maldonado, Ismael; Cortese, Pietro; Cosentino, Mauro Rogerio; Costa, Filippo; Crochet, Philippe; Cruz Albino, Rigoberto; Cuautle Flores, Eleazar; Cunqueiro Mendez, Leticia; Dahms, Torsten; Dainese, Andrea; Danu, Andrea; Das, Debasish; Das, Indranil; Das, Supriya; Dash, Ajay Kumar; Dash, Sadhana; De, Sudipan; De Caro, Annalisa; De Cataldo, Giacinto; De Cuveland, Jan; De Falco, Alessandro; De Gruttola, Daniele; De Marco, Nora; De Pasquale, Salvatore; Deisting, Alexander; Deloff, Andrzej; Denes, Ervin Sandor; D'Erasmo, Ginevra; Di Bari, Domenico; Di Mauro, Antonio; Di Nezza, Pasquale; Diaz Corchero, Miguel Angel; Dietel, Thomas; Dillenseger, Pascal; Divia, Roberto; Djuvsland, Oeystein; Dobrin, Alexandru Florin; Dobrowolski, Tadeusz Antoni; Domenicis Gimenez, Diogenes; Donigus, Benjamin; Dordic, Olja; Dubey, Anand Kumar; Dubla, Andrea; Ducroux, Laurent; Dupieux, Pascal; Ehlers Iii, Raymond James; Elia, Domenico; Engel, Heiko; Erazmus, Barbara Ewa; Erhardt, Filip; Eschweiler, Dominic; Espagnon, Bruno; Estienne, Magali Danielle; Esumi, Shinichi; Eum, Jongsik; Evans, David; Evdokimov, Sergey; Eyyubova, Gyulnara; Fabbietti, Laura; Fabris, Daniela; Faivre, Julien; Fantoni, Alessandra; Fasel, Markus; Feldkamp, Linus; Felea, Daniel; Feliciello, Alessandro; Feofilov, Grigorii; Ferencei, Jozef; Fernandez Tellez, Arturo; Gonzalez Ferreiro, Elena; Ferretti, Alessandro; Festanti, Andrea; Figiel, Jan; Araujo Silva Figueredo, Marcel; Filchagin, Sergey; Finogeev, Dmitry; Fionda, Fiorella; Fiore, Enrichetta Maria; Fleck, Martin Gabriel; Floris, Michele; Foertsch, Siegfried Valentin; Foka, Panagiota; Fokin, Sergey; Fragiacomo, Enrico; Francescon, Andrea; Frankenfeld, Ulrich Michael; Fuchs, Ulrich; Furget, Christophe; Furs, Artur; Fusco Girard, Mario; Gaardhoeje, Jens Joergen; Gagliardi, Martino; Gago Medina, Alberto Martin; Gallio, Mauro; Gangadharan, Dhevan Raja; Ganoti, Paraskevi; Gao, Chaosong; Garabatos Cuadrado, Jose; Garcia-Solis, Edmundo Javier; Gargiulo, Corrado; Gasik, Piotr Jan; Germain, Marie; Gheata, Andrei George; Gheata, Mihaela; Ghosh, Premomoy; Ghosh, Sanjay Kumar; Gianotti, Paola; Giubellino, Paolo; Giubilato, Piero; Gladysz-Dziadus, Ewa; Glassel, Peter; Gomez Ramirez, Andres; Gonzalez Zamora, Pedro; Gorbunov, Sergey; Gorlich, Lidia Maria; Gotovac, Sven; Grabski, Varlen; Graczykowski, Lukasz Kamil; Grelli, Alessandro; Grigoras, Alina Gabriela; Grigoras, Costin; Grigoryev, Vladislav; Grigoryan, Ara; Grigoryan, Smbat; Grynyov, Borys; Grion, Nevio; Grosse-Oetringhaus, Jan Fiete; Grossiord, Jean-Yves; Grosso, Raffaele; Guber, Fedor; Guernane, Rachid; Guerzoni, Barbara; Gulbrandsen, Kristjan Herlache; Gulkanyan, Hrant; Gunji, Taku; Gupta, Anik; Gupta, Ramni; Haake, Rudiger; Haaland, Oystein Senneset; Hadjidakis, Cynthia Marie; Haiduc, Maria; Hamagaki, Hideki; Hamar, Gergoe; Hanratty, Luke David; Hansen, Alexander; Harris, John William; Hartmann, Helvi; Harton, Austin Vincent; Hatzifotiadou, Despina; Hayashi, Shinichi; Heckel, Stefan Thomas; Heide, Markus Ansgar; Helstrup, Haavard; Herghelegiu, Andrei Ionut; Herrera Corral, Gerardo Antonio; Hess, Benjamin Andreas; Hetland, Kristin Fanebust; Hilden, Timo Eero; Hillemanns, Hartmut; Hippolyte, Boris; Hristov, Peter Zahariev; Huang, Meidana; Humanic, Thomas; Hussain, Nur; Hussain, Tahir; Hutter, Dirk; Hwang, Dae Sung; Ilkaev, Radiy; Ilkiv, Iryna; Inaba, Motoi; Ionita, Costin; Ippolitov, Mikhail; Irfan, Muhammad; Ivanov, Marian; Ivanov, Vladimir; Izucheev, Vladimir; Jacobs, Peter Martin; Jahnke, Cristiane; Jang, Haeng Jin; Janik, Malgorzata Anna; Pahula Hewage, Sandun; Jena, Chitrasen; Jena, Satyajit; Jimenez Bustamante, Raul Tonatiuh; Jones, Peter Graham; Jung, Hyungtaik; Jusko, Anton; Kalinak, Peter; Kalweit, Alexander Philipp; Kamin, Jason Adrian; Kang, Ju Hwan; Kaplin, Vladimir; Kar, Somnath; Karasu Uysal, Ayben; Karavichev, Oleg; Karavicheva, Tatiana; Karpechev, Evgeny; Kebschull, Udo Wolfgang; Keidel, Ralf; Keijdener, Darius Laurens; Keil, Markus; Khan, Kamal; Khan, Mohammed Mohisin; Khan, Palash; Khan, Shuaib Ahmad; Khanzadeev, Alexei; Kharlov, Yury; Kileng, Bjarte; Kim, Beomkyu; Kim, Do Won; Kim, Dong Jo; Kim, Hyeonjoong; Kim, Jinsook; Kim, Mimae; Kim, Minwoo; Kim, Se Yong; Kim, Taesoo; Kirsch, Stefan; Kisel, Ivan; Kiselev, Sergey; Kisiel, Adam Ryszard; Kiss, Gabor; Klay, Jennifer Lynn; Klein, Carsten; Klein, Jochen; Klein-Boesing, Christian; Kluge, Alexander; Knichel, Michael Linus; Knospe, Anders Garritt; Kobayashi, Taiyo; Kobdaj, Chinorat; Kofarago, Monika; Kollegger, Thorsten; Kolozhvari, Anatoly; Kondratev, Valerii; Kondratyeva, Natalia; Kondratyuk, Evgeny; Konevskikh, Artem; Kouzinopoulos, Charalampos; Kovalenko, Oleksandr; Kovalenko, Vladimir; Kowalski, Marek; Kox, Serge; Koyithatta Meethaleveedu, Greeshma; Kral, Jiri; Kralik, Ivan; Kravcakova, Adela; Krelina, Michal; Kretz, Matthias; Krivda, Marian; Krizek, Filip; Kryshen, Evgeny; Krzewicki, Mikolaj; Kubera, Andrew Michael; Kucera, Vit; Kugathasan, Thanushan; Kuhn, Christian Claude; Kuijer, Paulus Gerardus; Kulakov, Igor; Kumar, Jitendra; Lokesh, Kumar; Kurashvili, Podist; Kurepin, Alexander; Kurepin, Alexey; Kuryakin, Alexey; Kushpil, Svetlana; Kweon, Min Jung; Kwon, Youngil; La Pointe, Sarah Louise; La Rocca, Paola; Lagana Fernandes, Caio; Lakomov, Igor; Langoy, Rune; Lara Martinez, Camilo Ernesto; Lardeux, Antoine Xavier; Lattuca, Alessandra; Laudi, Elisa; Lea, Ramona; Leardini, Lucia; Lee, Graham Richard; Lee, Seongjoo; Legrand, Iosif; Lemmon, Roy Crawford; Lenti, Vito; Leogrande, Emilia; Leon Monzon, Ildefonso; Leoncino, Marco; Levai, Peter; Li, Shuang; Li, Xiaomei; Lien, Jorgen Andre; Lietava, Roman; Lindal, Svein; Lindenstruth, Volker; Lippmann, Christian; Lisa, Michael Annan; Ljunggren, Hans Martin; Lodato, Davide Francesco; Lonne, Per-Ivar; Loggins, Vera Renee; Loginov, Vitaly; Loizides, Constantinos; Lopez, Xavier Bernard; Lopez Torres, Ernesto; Lowe, Andrew John; Luettig, Philipp Johannes; Lunardon, Marcello; Luparello, Grazia; Ferreira Natal Da Luz, Pedro Hugo; Maevskaya, Alla; Mager, Magnus; Mahajan, Sanjay; Mahmood, Sohail Musa; Maire, Antonin; Majka, Richard Daniel; Malaev, Mikhail; Maldonado Cervantes, Ivonne Alicia; Malinina, Liudmila; Mal'Kevich, Dmitry; Malzacher, Peter; Mamonov, Alexander; Manceau, Loic Henri Antoine; Manko, Vladislav; Manso, Franck; Manzari, Vito; Marchisone, Massimiliano; Mares, Jiri; Margagliotti, Giacomo Vito; Margotti, Anselmo; Margutti, Jacopo; Marin, Ana Maria; Markert, Christina; Marquard, Marco; Martin, Nicole Alice; Martin Blanco, Javier; Martinengo, Paolo; Martinez Hernandez, Mario Ivan; Martinez-Garcia, Gines; Martinez Pedreira, Miguel; Martynov, Yevgen; Mas, Alexis Jean-Michel; Masciocchi, Silvia; Masera, Massimo; Masoni, Alberto; Massacrier, Laure Marie; Mastroserio, Annalisa; Masui, Hiroshi; Matyja, Adam Tomasz; Mayer, Christoph; Mazer, Joel Anthony; Mazzoni, Alessandra Maria; Mcdonald, Daniel; Meddi, Franco; Menchaca-Rocha, Arturo Alejandro; Meninno, Elisa; Mercado-Perez, Jorge; Meres, Michal; Miake, Yasuo; Mieskolainen, Matti Mikael; Mikhaylov, Konstantin; Milano, Leonardo; Milosevic, Jovan; Minervini, Lazzaro Manlio; Mischke, Andre; Mishra, Aditya Nath; Miskowiec, Dariusz Czeslaw; Mitra, Jubin; Mitu, Ciprian Mihai; Mohammadi, Naghmeh; Mohanty, Bedangadas; Molnar, Levente; Montano Zetina, Luis Manuel; Montes Prado, Esther; Morando, Maurizio; Moreira De Godoy, Denise Aparecida; Moretto, Sandra; Morreale, Astrid; Morsch, Andreas; Muccifora, Valeria; Mudnic, Eugen; Muhlheim, Daniel Michael; Muhuri, Sanjib; Mukherjee, Maitreyee; Muller, Hans; Mulligan, James Declan; Gameiro Munhoz, Marcelo; Murray, Sean; Musa, Luciano; Musinsky, Jan; Nandi, Basanta Kumar; Nania, Rosario; Nappi, Eugenio; Naru, Muhammad Umair; Nattrass, Christine; Nayak, Kishora; Nayak, Tapan Kumar; Nazarenko, Sergey; Nedosekin, Alexander; Nellen, Lukas; Ng, Fabian; Nicassio, Maria; Niculescu, Mihai; Niedziela, Jeremi; Nielsen, Borge Svane; Nikolaev, Sergey; Nikulin, Sergey; Nikulin, Vladimir; Noferini, Francesco; Nomokonov, Petr; Nooren, Gerardus; Norman, Jaime; Nyanin, Alexander; Nystrand, Joakim Ingemar; Oeschler, Helmut Oskar; Oh, Saehanseul; Oh, Sun Kun; Ohlson, Alice Elisabeth; Okatan, Ali; Okubo, Tsubasa; Olah, Laszlo; Oleniacz, Janusz; Oliveira Da Silva, Antonio Carlos; Oliver, Michael Henry; Onderwaater, Jacobus; Oppedisano, Chiara; Ortiz Velasquez, Antonio; Oskarsson, Anders Nils Erik; Otwinowski, Jacek Tomasz; Oyama, Ken; Ozdemir, Mahmut; Pachmayer, Yvonne Chiara; Pagano, Paola; Paic, Guy; Pajares Vales, Carlos; Pal, Susanta Kumar; Pan, Jinjin; Pandey, Ashutosh Kumar; Pant, Divyash; Papikyan, Vardanush; Pappalardo, Giuseppe; Pareek, Pooja; Park, Woojin; Parmar, Sonia; Passfeld, Annika; Paticchio, Vincenzo; Patra, Rajendra Nath; Paul, Biswarup; Peitzmann, Thomas; Pereira Da Costa, Hugo Denis Antonio; Pereira De Oliveira Filho, Elienos; Peresunko, Dmitry Yurevich; Perez Lara, Carlos Eugenio; Peskov, Vladimir; Pestov, Yury; Petracek, Vojtech; Petrov, Viacheslav; Petrovici, Mihai; Petta, Catia; Piano, Stefano; Pikna, Miroslav; Pillot, Philippe; Pinazza, Ombretta; Pinsky, Lawrence; Piyarathna, Danthasinghe; Ploskon, Mateusz Andrzej; Planinic, Mirko; Pluta, Jan Marian; Pochybova, Sona; Podesta Lerma, Pedro Luis Manuel; Poghosyan, Martin; Polishchuk, Boris; Poljak, Nikola; Poonsawat, Wanchaloem; Pop, Amalia; Porteboeuf, Sarah Julie; Porter, R Jefferson; Pospisil, Jan; Prasad, Sidharth Kumar; Preghenella, Roberto; Prino, Francesco; Pruneau, Claude Andre; Pshenichnov, Igor; Puccio, Maximiliano; Puddu, Giovanna; Pujahari, Prabhat Ranjan; Punin, Valery; Putschke, Jorn Henning; Qvigstad, Henrik; Rachevski, Alexandre; Raha, Sibaji; Rajput, Sonia; Rak, Jan; Rakotozafindrabe, Andry Malala; Ramello, Luciano; Raniwala, Rashmi; Raniwala, Sudhir; Rasanen, Sami Sakari; Rascanu, Bogdan Theodor; Rathee, Deepika; Read, Kenneth Francis; Real, Jean-Sebastien; Redlich, Krzysztof; Reed, Rosi Jan; Rehman, Attiq Ur; Reichelt, Patrick Simon; Reidt, Felix; Ren, Xiaowen; Renfordt, Rainer Arno Ernst; Reolon, Anna Rita; Reshetin, Andrey; Rettig, Felix Vincenz; Revol, Jean-Pierre; Reygers, Klaus Johannes; Riabov, Viktor; Ricci, Renato Angelo; Richert, Tuva Ora Herenui; Richter, Matthias Rudolph; Riedler, Petra; Riegler, Werner; Riggi, Francesco; Ristea, Catalin-Lucian; Rivetti, Angelo; Rocco, Elena; Rodriguez Cahuantzi, Mario; Rodriguez Manso, Alis; Roeed, Ketil; Rogochaya, Elena; Rohr, David Michael; Roehrich, Dieter; Romita, Rosa; Ronchetti, Federico; Ronflette, Lucile; Rosnet, Philippe; Rossi, Andrea; Roukoutakis, Filimon; Roy, Ankhi; Roy, Christelle Sophie; Roy, Pradip Kumar; Rubio Montero, Antonio Juan; Rui, Rinaldo; Russo, Riccardo; Ryabinkin, Evgeny; Ryabov, Yury; Rybicki, Andrzej; Sadovskiy, Sergey; Safarik, Karel; Sahlmuller, Baldo; Sahoo, Pragati; Sahoo, Raghunath; Sahoo, Sarita; Sahu, Pradip Kumar; Saini, Jogender; Sakai, Shingo; Saleh, Mohammad Ahmad; Salgado Lopez, Carlos Alberto; Salzwedel, Jai Samuel Nielsen; Sambyal, Sanjeev Singh; Samsonov, Vladimir; Sanchez Castro, Xitzel; Sandor, Ladislav; Sandoval, Andres; Sano, Masato; Santagati, Gianluca; Sarkar, Debojit; Scapparone, Eugenio; Scarlassara, Fernando; Scharenberg, Rolf Paul; Schiaua, Claudiu Cornel; Schicker, Rainer Martin; Schmidt, Christian Joachim; Schmidt, Hans Rudolf; Schuchmann, Simone; Schukraft, Jurgen; Schulc, Martin; Schuster, Tim Robin; Schutz, Yves Roland; Schwarz, Kilian Eberhard; Schweda, Kai Oliver; Scioli, Gilda; Scomparin, Enrico; Scott, Rebecca Michelle; Seeder, Karin Soraya; Seger, Janet Elizabeth; Sekiguchi, Yuko; Selyuzhenkov, Ilya; Senosi, Kgotlaesele; Seo, Jeewon; Serradilla Rodriguez, Eulogio; Sevcenco, Adrian; Shabanov, Arseniy; Shabetai, Alexandre; Shadura, Oksana; Shahoyan, Ruben; Shangaraev, Artem; Sharma, Ankita; Sharma, Natasha; Shigaki, Kenta; Shtejer Diaz, Katherin; Sibiryak, Yury; Siddhanta, Sabyasachi; Sielewicz, Krzysztof Marek; Siemiarczuk, Teodor; Silvermyr, David Olle Rickard; Silvestre, Catherine Micaela; Simatovic, Goran; Simonetti, Giuseppe; Singaraju, Rama Narayana; Singh, Ranbir; Singha, Subhash; Singhal, Vikas; Sinha, Bikash; Sarkar - Sinha, Tinku; Sitar, Branislav; Sitta, Mario; Skaali, Bernhard; Skjerdal, Kyrre; Slupecki, Maciej; Smirnov, Nikolai; Snellings, Raimond; Snellman, Tomas Wilhelm; Soegaard, Carsten; Soltz, Ron Ariel; Song, Jihye; Song, Myunggeun; Song, Zixuan; Soramel, Francesca; Sorensen, Soren Pontoppidan; Spacek, Michal; Spiriti, Eleuterio; Sputowska, Iwona Anna; Spyropoulou-Stassinaki, Martha; Srivastava, Brijesh Kumar; Stachel, Johanna; Stan, Ionel; Stefanek, Grzegorz; Steinpreis, Matthew Donald; Stenlund, Evert Anders; Steyn, Gideon Francois; Stiller, Johannes Hendrik; Stocco, Diego; Strmen, Peter; Alarcon Do Passo Suaide, Alexandre; Sugitate, Toru; Suire, Christophe Pierre; Suleymanov, Mais Kazim Oglu; Sultanov, Rishat; Sumbera, Michal; Symons, Timothy; Szabo, Alexander; Szanto De Toledo, Alejandro; Szarka, Imrich; Szczepankiewicz, Adam; Szymanski, Maciej Pawel; Takahashi, Jun; Tanaka, Naoto; Tangaro, Marco-Antonio; Tapia Takaki, Daniel Jesus; Tarantola Peloni, Attilio; Tariq, Mohammad; Tarzila, Madalina-Gabriela; Tauro, Arturo; Tejeda Munoz, Guillermo; Telesca, Adriana; Terasaki, Kohei; Terrevoli, Cristina; Teyssier, Boris; Thaeder, Jochen Mathias; Thomas, Deepa; Tieulent, Raphael Noel; Timmins, Anthony Robert; Toia, Alberica; Trogolo, Stefano; Trubnikov, Victor; Trzaska, Wladyslaw Henryk; Tsuji, Tomoya; Tumkin, Alexandr; Turrisi, Rosario; Tveter, Trine Spedstad; Ullaland, Kjetil; Uras, Antonio; Usai, Gianluca; Utrobicic, Antonija; Vajzer, Michal; Vala, Martin; Valencia Palomo, Lizardo; Vallero, Sara; Van Der Maarel, Jasper; Van Hoorne, Jacobus Willem; Van Leeuwen, Marco; Vanat, Tomas; Vande Vyvre, Pierre; Varga, Dezso; Diozcora Vargas Trevino, Aurora; Vargyas, Marton; Varma, Raghava; Vasileiou, Maria; Vasiliev, Andrey; Vauthier, Astrid; Vechernin, Vladimir; Veen, Annelies Marianne; Veldhoen, Misha; Velure, Arild; Venaruzzo, Massimo; Vercellin, Ermanno; Vergara Limon, Sergio; Vernet, Renaud; Verweij, Marta; Vickovic, Linda; Viesti, Giuseppe; Viinikainen, Jussi Samuli; Vilakazi, Zabulon; Villalobos Baillie, Orlando; Vinogradov, Alexander; Vinogradov, Leonid; Vinogradov, Yury; Virgili, Tiziano; Vislavicius, Vytautas; Viyogi, Yogendra; Vodopyanov, Alexander; Volkl, Martin Andreas; Voloshin, Kirill; Voloshin, Sergey; Volpe, Giacomo; Von Haller, Barthelemy; Vorobyev, Ivan; Vranic, Danilo; Vrlakova, Janka; Vulpescu, Bogdan; Vyushin, Alexey; Wagner, Boris; Wagner, Jan; Wang, Hongkai; Wang, Mengliang; Wang, Yifei; Watanabe, Daisuke; Weber, Michael; Weber, Steffen Georg; Wessels, Johannes Peter; Westerhoff, Uwe; Wiechula, Jens; Wikne, Jon; Wilde, Martin Rudolf; Wilk, Grzegorz Andrzej; Wilkinson, Jeremy John; Williams, Crispin; Windelband, Bernd Stefan; Winn, Michael Andreas; Yaldo, Chris G; Yamaguchi, Yorito; Yang, Hongyan; Yang, Ping; Yano, Satoshi; Yin, Zhongbao; Yokoyama, Hiroki; Yoo, In-Kwon; Yurchenko, Volodymyr; Yushmanov, Igor; Zaborowska, Anna; Zaccolo, Valentina; Zaman, Ali; Zampolli, Chiara; Correia Zanoli, Henrique Jose; Zaporozhets, Sergey; Zarochentsev, Andrey; Zavada, Petr; Zavyalov, Nikolay; Zbroszczyk, Hanna Paulina; Zgura, Sorin Ion; Zhalov, Mikhail; Zhang, Haitao; Zhang, Xiaoming; Zhang, Yonghong; Zhao, Chengxin; Zhigareva, Natalia; Zhou, Daicui; Zhou, You; Zhou, Zhuo; Zhu, Hongsheng; Zhu, Jianhui; Zhu, Xiangrong; Zichichi, Antonino; Zimmermann, Alice; Zimmermann, Markus Bernhard; Zinovjev, Gennady; Zyzak, Maksym

    2015-09-15

    We report the first measurement at the LHC of coherent photoproduction of $\\rho^0$ mesons in ultra-peripheral Pb-Pb collisions. The invariant mass and transverse momentum distributions for $\\rho^0$ production are studied in the $\\pi^+ \\pi^-$ decay channel at mid-rapidity. The production cross section in the rapidity range $|y|<0.5$ is found to be $\\mathrm{d}\\sigma/\\mathrm{d}y = 425 \\pm 10 \\, (\\mathrm{stat.})$ $^{+42}_{-50} \\, (\\mathrm{sys.})$ mb. Coherent $\\rho^0$ production is studied with and without requirement of nuclear breakup, and the fractional yields for various breakup scenarios are presented. The results are compared with those from lower energies and with model predictions based on the Glauber model and the color dipole model. The measured cross section is found to be inconsistent with a scaling of the $\\gamma$-nucleon cross section using the Glauber model.

  5. Rho0 production and possible modification in Au+Au and p+p collisions at square root [sNN] = 200 GeV.

    Science.gov (United States)

    Adams, J; Adler, C; Aggarwal, M M; Ahammed, Z; Amonett, J; Anderson, B D; Arkhipkin, D; Averichev, G S; Badyal, S K; Balewski, J; Barannikova, O; Barnby, L S; Baudot, J; Bekele, S; Belaga, V V; Bellwied, R; Berger, J; Bezverkhny, B I; Bhardwaj, S; Bhati, A K; Bichsel, H; Billmeier, A; Bland, L C; Blyth, C O; Bonner, B E; Botje, M; Boucham, A; Brandin, A; Bravar, A; Cadman, R V; Cai, X Z; Caines, H; Calderón de la Barca Sánchez, M; Carroll, J; Castillo, J; Cebra, D; Chaloupka, P; Chattopadhyay, S; Chen, H F; Chen, Y; Chernenko, S P; Cherney, M; Chikanian, A; Christie, W; Coffin, J P; Cormier, T M; Cramer, J G; Crawford, H J; Das, D; Das, S; Derevschikov, A A; Didenko, L; Dietel, T; Dong, W J; Dong, X; Draper, J E; Du, F; Dubey, A K; Dunin, V B; Dunlop, J C; Dutta Majumdar, M R; Eckardt, V; Efimov, L G; Emelianov, V; Engelage, J; Eppley, G; Erazmus, B; Estienne, M; Fachini, P; Faine, V; Faivre, J; Fatemi, R; Filimonov, K; Filip, P; Finch, E; Fisyak, Y; Flierl, D; Foley, K J; Fu, J; Gagliardi, C A; Gagunashvili, N; Gans, J; Ganti, M S; Gaudichet, L; Geurts, F; Ghazikhanian, V; Ghosh, P; Gonzalez, J E; Grachov, O; Grebenyuk, O; Gronstal, S; Grosnick, D; Guertin, S M; Gupta, A; Gutierrez, T D; Hallman, T J; Hamed, A; Hardtke, D; Harris, J W; Heinz, M; Henry, T W; Heppelmann, S; Hippolyte, B; Hirsch, A; Hjort, E; Hoffmann, G W; Horsley, M; Huang, H Z; Huang, S L; Hughes, E; Humanic, T J; Igo, G; Ishihara, A; Jacobs, P; Jacobs, W W; Janik, M; Jiang, H; Johnson, I; Jones, P G; Judd, E G; Kabana, S; Kaplan, M; Keane, D; Khodyrev, V Yu; Kiryluk, J; Kisiel, A; Klay, J; Klein, S R; Klyachko, A; Koetke, D D; Kollegger, T; Kopytine, M; Kotchenda, L; Kovalenko, A D; Kramer, M; Kravtsov, P; Kravtsov, V I; Krueger, K; Kuhn, C; Kulikov, A I; Kumar, A; Kunde, G J; Kunz, C L; Kutuev, R Kh; Kuznetsov, A A; Lamont, M A C; Landgraf, J M; Lange, S; Lasiuk, B; Laue, F; Lauret, J; Lebedev, A; Lednický, R; LeVine, M J; Li, C; Li, Q; Lindenbaum, S J; Lisa, M A; Liu, F; Liu, L; Liu, Z; Liu, Q J; Ljubicic, T; Llope, W J; Long, H; Longacre, R S; Lopez-Noriega, M; Love, W A; Ludlam, T; Lynn, D; Ma, J; Ma, Y G; Magestro, D; Mahajan, S; Mangotra, L K; Mahapatra, D P; Majka, R; Manweiler, R; Margetis, S; Markert, C; Martin, L; Marx, J; Matis, H S; Matulenko, Yu A; McClain, C J; McShane, T S; Meissner, F; Melnick, Yu; Meschanin, A; Miller, M L; Milosevich, Z; Minaev, N G; Mironov, C; Mischke, A; Mishra, D; Mitchell, J; Mohanty, B; Molnar, L; Moore, C F; Mora-Corral, M J; Morozov, D A; Morozov, V; De Moura, M M; Munhoz, M G; Nandi, B K; Nayak, S K; Nayak, T K; Nelson, J M; Netrakanti, P K; Nikitin, V A; Nogach, L V; Norman, B; Nurushev, S B; Odyniec, G; Ogawa, A; Okorokov, V; Oldenburg, M; Olson, D; Paic, G; Pal, S K; Panebratsev, Y; Panitkin, S Y; Pavlinov, A I; Pawlak, T; Peitzmann, T; Perevoztchikov, V; Perkins, C; Peryt, W; Petrov, V A; Phatak, S C; Picha, R; Planinic, M; Pluta, J; Porile, N; Porter, J; Poskanzer, A M; Potekhin, M; Potrebenikova, E; Potukuchi, B V K S; Prindle, D; Pruneau, C; Putschke, J; Rai, G; Rakness, G; Raniwala, R; Raniwala, S; Ravel, O; Ray, R L; Razin, S V; Reichhold, D; Reid, J G; Renault, G; Retiere, F; Ridiger, A; Ritter, H G; Roberts, J B; Rogachevski, O V; Romero, J L; Rose, A; Roy, C; Ruan, L J; Sahoo, R; Sakrejda, I; Salur, S; Sandweiss, J; Savin, I; Schambach, J; Scharenberg, R P; Schmitz, N; Schroeder, L S; Schweda, K; Seger, J; Seyboth, P; Shahaliev, E; Shao, M; Shao, W; Sharma, M; Shestermanov, K E; Shimanskii, S S; Singaraju, R N; Simon, F; Skoro, G; Smirnov, N; Snellings, R; Sood, G; Sorensen, P; Sowinski, J; Speltz, J; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stock, R; Stolpovsky, A; Strikhanov, M; Stringfellow, B; Struck, C; Suaide, A A P; Sugarbaker, E; Suire, C; Sumbera, M; Surrow, B; Symons, T J M; Szanto de Toledo, A; Szarwas, P; Tai, A; Takahashi, J; Tang, A H; Thein, D; Thomas, J H; Timoshenko, S; Tokarev, M; Tonjes, M B; Trainor, T A; Trentalange, S; Tribble, R E; Tsai, O; Ullrich, T; Underwood, D G; Van Buren, G; VanderMolen, A M; Varma, R; Vasilevski, I; Vasiliev, A N; Vernet, R; Vigdor, S E; Viyogi, Y P; Voloshin, S A; Vznuzdaev, M; Waggoner, W; Wang, F; Wang, G; Wang, G; Wang, X L; Wang, Y; Wang, Z M; Ward, H; Watson, J W; Webb, J C; Wells, R; Westfall, G D; Whitten, C; Wieman, H; Willson, R; Wissink, S W; Witt, R; Wood, J; Wu, J; Xu, N; Xu, Z; Xu, Z Z; Yamamoto, E; Yepes, P; Yurevich, V I; Yuting, B; Zanevski, Y V; Zhang, H; Zhang, W M; Zhang, Z P; Zhaomin, Z P; Zizong, Z P; Zołnierczuk, P A; Zoulkarneev, R; Zoulkarneeva, J; Zubarev, A N

    2004-03-05

    We report results on rho(770)(0)-->pi(+)pi(-) production at midrapidity in p+p and peripheral Au+Au collisions at sqrt[s(NN)]=200 GeV. This is the first direct measurement of rho(770)(0)-->pi(+)pi(-) in heavy-ion collisions. The measured rho(0) peak in the invariant mass distribution is shifted by approximately 40 MeV/c(2) in minimum bias p+p interactions and approximately 70 MeV/c(2) in peripheral Au+Au collisions. The rho(0) mass shift is dependent on transverse momentum and multiplicity. The modification of the rho(0) meson mass, width, and shape due to phase space and dynamical effects are discussed.

  6. Using quasi-elastic neutron diffraction to study positive electrode for lithium and sodium-ion batteries

    International Nuclear Information System (INIS)

    Pramudita, James C.; Sharma, Neeraj

    2015-01-01

    Sodium-ion batteries has recently been proposed as the alternative for lithium-ion batteries to be the low cost energy storage system. However, challenges still remains for the development of sodium-ion batteries. Optimization of electrode materials and electrolyte capable of insertion/extraction of sodium-ion in a safe and economic way under high current density is needed in order to produce commercially viable sodium-ion batteries. While possible positive electrode material is more prevalent than negative electrode material, many of these material still need further understanding. Quasi-elastic Neutron Scatteringis a technique that utilize the inelastic Neutron Scatteringthat can be used to study solid-state diffusion in materials. This technique can be used to study the diffusion of sodium-ion under electric field through the electrolyte and positive electrode materials in order to further understand the mechanism of sodium insertion/extraction in a working battery. This technique can also be used to study available positive electrode material for lithium-ion batteries to further understand the mechanism of lithium-ion diffusion in current working lithiumion batteries.

  7. Using Quasi-Elastic Events to Measure Neutrino Oscillations with MINOS Detectors in the NuMI Neutrino Beam

    Energy Technology Data Exchange (ETDEWEB)

    Watabe, Masaki [Texas A & M Univ., College Station, TX (United States)

    2010-05-01

    MINOS (Main Injector Neutrino Oscillation Search) experiment has been designed to search for a change in the avor composition of a beam of muon neutrinos as they travel between the Near Detector at Fermi National Accelerator Laboratory and the Far Detector in the Soudan mine in Minnesota, 735 km from the target. The MINOS oscillation analysis is mainly performed with the charged current (CC) events and sensitive to constrain high- Δm2 values. However, the quasi-elastic (QEL) charged current interaction is dominant in the energy region important to access low- m2 values. For further improvement, the QEL oscillation analysis is performed in this dissertation. A data sample based on a total of 2.50 x 1020 POT is used for this analysis. In summary, 55 QEL-like events are observed at the Far detector while 87.06 ± 13.17 (syst:) events are expected with null oscillation hypothesis. These data are consistent with disappearance via oscillation with m2 = 2:10 0.37 (stat:) ± 0.24 (syst:) eV2 and the maximal mixing angle.

  8. Synchrotron radiation-based quasi-elastic scattering using time-domain interferometry with multi-line gamma rays.

    Science.gov (United States)

    Saito, Makina; Masuda, Ryo; Yoda, Yoshitaka; Seto, Makoto

    2017-10-02

    We developed a multi-line time-domain interferometry (TDI) system using 14.4 keV Mössbauer gamma rays with natural energy widths of 4.66 neV from 57 Fe nuclei excited using synchrotron radiation. Electron density fluctuations can be detected at unique lengths ranging from 0.1 nm to a few nm on time scales from several nanoseconds to the sub-microsecond order by quasi-elastic gamma-ray scattering (QGS) experiments using multi-line TDI. In this report, we generalize the established expression for a time spectrum measured using an identical single-line gamma-ray emitter pair to the case of a nonidentical pair of multi-line gamma-ray emitters by considering the finite energy width of the incident synchrotron radiation. The expression obtained illustrates the unique characteristics of multi-line TDI systems, where the finite incident energy width and use of a nonidentical emitter pair produces further information on faster sub-picosecond-scale dynamics in addition to the nanosecond dynamics; this was demonstrated experimentally. A normalized intermediate scattering function was extracted from the spectrum and its relaxation form was determined for a relaxation time of the order of 1 μs, even for relatively large momentum transfer of ~31 nm -1 . The multi-line TDI method produces a microscopic relaxation picture more rapidly and accurately than conventional single-line TDI.

  9. Measurement of the Antineutrino Double-Differential Charged-Current Quasi-Elastic Scattering Cross Section at MINERvA

    Energy Technology Data Exchange (ETDEWEB)

    Patrick, Cheryl [Northwestern U.

    2016-01-01

    Next-generation neutrino oscillation experiments, such as DUNE and Hyper-Kamiokande, hope to measure charge-parity (CP) violation in the lepton sector. In order to do this, they must dramatically reduce their current levels of uncertainty, particularly those due to neutrino-nucleus interaction models. As CP violation is a measure of the difference between the oscillation properties of neutrinos and antineutrinos, data about how the less-studied antineutrinos interact is especially valuable. We present the MINERvA experiment's first double-differential scattering cross sections for antineutrinos on scintillator, in the few-GeV range relevant to experiments such as DUNE and NOvA. We also present total antineutrino-scintillator quasi-elastic cross sections as a function of energy, which we compare to measurements from previous experiments. As well as being useful to help reduce oscillation experiments' uncertainty, our data can also be used to study the prevalence of various cor relation and final-state interaction effects within the nucleus. We compare to models produced by different model generators, and are able to draw first conclusions about the predictions of these models.

  10. Exclusive Electroproduction of meson rho on the nucleon Virtualite Intermediate With the CLAS Detector at Jlab; Electroproduction Exclusive de meson rho sur le nucleon Virtualite Intermediaire Avec le Detecteur CLAS at Jlab

    Energy Technology Data Exchange (ETDEWEB)

    Hadjidakis, Cynthia [Univ. of Paris-Sud, Orsay (France). Inst. of Nuclear Physics of Orsay

    2002-12-17

    This report presents the exclusive rho0 meson electroproduction on the nucleon at intermediate square momentum transfers Q2 (1.5 < Q2 < 3 GeV2) and above the resonance region. The experiment has been taken place at the Jefferson laboratory with the CLAS detector, with a 4.2 GeV beam energy on a hydrogen target in the February-March 1999 period. They present the results and in particular the L/T separated cross sections. This experimentally unexplored domain experimentally is at the intersection between traditional ''soft'' hadronic physics models (VDM and Regge inspired models) and ''hard'' pQCD inspired approaches (recently introduced Generalized Parton Distribution). They discuss both approaches and their domain of validity.

  11. Quasi-elastic neutron scattering study of a re-entrant side-chain liquid-crystal polyacrylate

    Science.gov (United States)

    Benguigui, L.; Noirez, L.; Kahn, R.; Keller, P.; Lambert, M.; Cohen de Lara, E.

    1991-04-01

    We present a first investigation of the dynamics of a side chain liquid crystal polyacrylate in the isotropic (I), nematic (N), smectic A (SA), and re-entrant nematic (NRe) phases by means of quasi-elastic neutron scattering. The motion or/and the mobility of the mesogen protons decreases as soon as the temperature decreases after the isotropic-nematic transition. The I-N and SA-NRe transitions corrspond to a jump in the curve of the Elastic Incoherent Structure Factor (ratio: elastic scattering/ total scattering) versus temperature, on the other hand the transition N-SA occurs without any change of slope. We conclude that the local order is very similar in the nematic and the smectic A phases. Nous présentons une première étude dynamique par diffusion quasi-élastique des neutrons, d'un échantillon de polyacrylate mésomorphe en peigne dans chacune des phases : isotrope, nématique, smectique et nématique rentrante. On montre que le mouvement et/ou la mobilité des protons du mésogène se restreint à mesure que la température diminue après la transition isotrope-nématique. Contrairement à la transition N-SA, les transitions I-N et SA-NRe correspondent à une discontinuité dans la courbe du Facteur de Structure Incohérent Elastique (rapport : intensité élastique/intensité totale) en fonction de la température ; l'ordre local semble donc très proche pour les phases nématique et smectique.

  12. Probing the hydrogen equilibrium and kinetics in zeolite imidazolate frameworks via molecular dynamics and quasi-elastic neutron scattering experiments.

    Science.gov (United States)

    Pantatosaki, Evangelia; Jobic, Hervé; Kolokolov, Daniil I; Karmakar, Shilpi; Biniwale, Rajesh; Papadopoulos, George K

    2013-01-21

    The problem of simulating processes involving equilibria and dynamics of guest sorbates within zeolitic imidazolate frameworks (ZIF) by means of molecular dynamics (MD) computer experiments is of growing importance because of the promising role of ZIFs as molecular "traps" for clean energy applications. A key issue for validating such an atomistic modeling attempt is the possibility of comparing the MD results, with real experiments being able to capture analogous space and time scales to the ones pertained to the computer experiments. In the present study, this prerequisite is fulfilled through the quasi-elastic neutron scattering technique (QENS) for measuring self-diffusivity, by elaborating the incoherent scattering signal of hydrogen nuclei. QENS and MD experiments were performed in parallel to probe the hydrogen motion, for the first time in ZIF members. The predicted and measured dynamics behaviors show considerable concentration variation of the hydrogen self-diffusion coefficient in the two topologically different ZIF pore networks of this study, the ZIF-3 and ZIF-8. Modeling options such as the flexibility of the entire matrix versus a rigid framework version, the mobility of the imidazolate ligand, and the inclusion of quantum mechanical effects in the potential functions were examined in detail for the sorption thermodynamics and kinetics of hydrogen and also of deuterium, by employing MD combined with Widom averaging towards studying phase equilibria. The latter methodology ensures a rigorous and efficient way for post-processing the dynamics trajectory, thereby avoiding stochastic moves via Monte Carlo simulation, over the large number of configurational degrees of freedom a nonrigid framework encompasses.

  13. Quasi-elastic transfer and charge-exchange reactions in collisions of 48Ti on 42Ca and 26Mg

    International Nuclear Information System (INIS)

    Brendel, C.

    1985-01-01

    At the GSI magnetic spectrometer quasi-elastic transfer and charge-exchange reactions of the system 48 Ti + 42 Ca at incident energies E lab = 240, 300, and 385 MeV and additionally at the higher projectile energy the system 48 Ti + 26 Mg were studied each in the excitation energy range up to E x ≅ 80 MeV. The transition strength was for each particle-hole configuration of the final system calculated by means of the DWBA and subsequently folded with a Breit-Wigner distribution. The localization of the strength of the cross section and the specific structure of the energy spectra were at incident energies between 6 and 8 MeV/amu for all angles well reproduced. By an extension of the core-excitation model to many-stage reactions the charge-exchange reaction 48 Ti + 42 Ca → 48 Sc + 42 Sc could be described as sequential two-stage process. In the two-neutron stripping reaction 48 Ti + 42 Ca → 46 Ti + 44 Ca a surprisingly narrow line with a width of the experimental resolution and an excitation energy of E x = 17.8 MeV was measured at angles smaller than the grazing angle. In the 48 Ti + 26 Mg system the corresponding 46 Ti spectra show also under forward angles structures at excitation energies between 8 and 16 MeV. These lines can be explained as two-neutron states with high spin. (orig./HSI) [de

  14. Quasi-elastic scattering

    International Nuclear Information System (INIS)

    Pizzi, J.R.

    1975-01-01

    In a first part, the kinematical conditions which are chosen to study quasi free scattering reactions are presented, as well as the impulse approximation which is used to interpret the experimental data. Then, the evolution of the study of these reactions in the last few years is analyzed. Three recent experiments are presented and discussed. Two of them deal with α-clusters studied by (p,pα) reaction at 157 and 600MeV. The third is concerned with d, t and 3 He clusters studied by (p,px) reaction at 75MeV [fr

  15. Measurement of the Charged-Current Quasi-Elastic Cross-Section for Electron Neutrinos on a Hydrocarbon Target

    Energy Technology Data Exchange (ETDEWEB)

    Wolcott, Jeremy [Univ. of Rochester, NY (United States)

    2016-01-01

    Appearance-type neutrino oscillation experiments, which observe the transition from muon neutrinos to electron neutrinos, promise to help answer some of the fundamental questions surrounding physics in the post-Standard-Model era. Because they wish to observe the interactions of electron neutrinos in their detectors, and because the power of current results is typically limited by their systematic uncertainties, these experiments require precise estimates of the cross-section for electron neutrino interactions. Of particular interest is the charged-current quasi-elastic (CCQE) process, which gures signi cantly in the composition of the reactions observed at the far detector. However, no experimental measurements of this crosssection currently exist for electron neutrinos; instead, current experiments typically work from the abundance of muon neutrino CCQE cross-section data and apply corrections from theoretical arguments to obtain a prediction for electron neutrinos. Veri cation of these predictions is challenging due to the di culty of constructing an electron neutrino beam, but the advent of modern high-intensity muon neutrino beams|together with the percent-level electron neutrino impurity inherent in these beams| nally presents the opportunity to make such a measurement. We report herein the rst-ever measurement of a cross-section for an exclusive state in electron neutrino scattering, which was made using the MINER A detector in the NuMI neutrino beam at Fermilab. We present the electron neutrino CCQE di erential cross-sections, which are averaged over neutrinos of energies 1-10 GeV (with mean energy of about 3 GeV), in terms of various kinematic variables: nal-state electron angle, nal-state electron energy, and the square of the fourmomentum transferred to the nucleus by the neutrino , Q2. We also provide a total cross-section vs. neutrino energy. While our measurement of this process is found to be in agreement with the predictions of the GENIE

  16. Exotic hybrid mesons in hard electroproduction

    International Nuclear Information System (INIS)

    Anikin, I.V.; Pire, B.; Szymanowski, L.; Teryaev, O.V.; Wallon, S.

    2005-01-01

    We estimate the sizeable cross section for deep exclusive electroproduction of an exotic J PC =1 -+ hybrid meson in the Bjorken regime. The production amplitude scales like the one for usual meson electroproduction, i.e., as 1/Q 2 . This is due to the nonvanishing leading twist distribution amplitude for the hybrid meson, which may be normalized thanks to its relation to the energy-momentum tensor and to the QCD sum rules technique. The hard amplitude is considered up to next-to-leading order in α S and we explore the consequences of fixing the renormalization scale ambiguity through the Brodsky-Lepage-Mackenzie (BLM) procedure. We study the particular case where the hybrid meson decays through a πη meson pair. We discuss the πη generalized distribution amplitude and then calculate the production amplitude for this process. We propose a forward-backward asymmetry in the production of π and η mesons as a signal for the hybrid meson production. We briefly comment on hybrid electroproduction at very high energy, in the diffractive limit where a QCD Odderon exchange mechanism should dominate. The conclusion of our study is that hard electroproduction is a promising way to study exotic hybrid mesons, in particular, at JLAB, HERA (HERMES), or CERN (Compass)

  17. {phi} meson electroproduction at small Bjorken-x

    Energy Technology Data Exchange (ETDEWEB)

    Kroll, P. [Wuppertal Univ., Fachbereich Physik (Germany)

    2005-07-01

    It is reported on an analysis of {phi}-meson electroproduction at small Bjorken-x(x{sub B{sub j}}) within the handbag approach. The amplitudes can be factorized into generalized parton distribution (GPDs) and a partonic subprocess, electroproduction off gluons. Cross-sections and spin density matrix elements are evaluated for {phi}-meson electroproduction and found to be in fair agreement with recent HERA data. (author)

  18. Excited states of virtual clusters in a nucleus and the processes of quasi-elastic cluster knock-out at high energies

    International Nuclear Information System (INIS)

    Golovanova, N.F.; Il'in, I.M.; Neudatchin, V.G.; Smirnov, Yu.F.; Tchuvil'sky, Yu.M.

    1976-01-01

    The quasi-elastic knock-out of nucleon clusters from nuclei by an incident high-energy hadron is considered within the framework of the Glauber-Sitenko multiple scattering theory. It is shown that the significant contribution to the cross section for the process comes not only from the hadron elastic scattering by a nonexcited virtual cluster but also from collisions with an excited virtual cluster, accompanied by de-excitation of this cluster. This necessitates modification of the usual theory of quasi-elastic cluster knock-out. First, the angular correlations of the knocked-out cluster and scattered hadron are no longer determined by the momentum distribution of the cluster in the nucleus. They are determined by another form factor F(q) which can be called the modified momentum distribution. Secondly, the meaning and values of the effective numbers of clusters Nsup(eff) have been changed. Thirdly, the characteristics of the processes depend not only on the modulus of momentum q, which the cluster had in the nucleus, but also on its direction relative to an incident beam. A method has been developed for the calculation of the fractional parentage coefficients, which are necessary for the calculation of the cluster knock-out from the p-shell nuclei. (Auth.)

  19. A new apparatus design for high temperature (up to 950 °C) quasi-elastic neutron scattering in a controlled gaseous environment

    International Nuclear Information System (INIS)

    Al-Wahish, Amal; Armitage, D.; Hill, B.; Mills, R.; Santodonato, L.; Herwig, K. W.; Al-Binni, U.; Jalarvo, N.; Mandrus, D.

    2015-01-01

    A design for a sample cell system suitable for high temperature Quasi-Elastic Neutron Scattering (QENS) experiments is presented. The apparatus was developed at the Spallation Neutron Source in Oak Ridge National Lab where it is currently in use. The design provides a special sample cell environment under controlled humid or dry gas flow over a wide range of temperature up to 950 °C. Using such a cell, chemical, dynamical, and physical changes can be studied in situ under various operating conditions. While the cell combined with portable automated gas environment system is especially useful for in situ studies of microscopic dynamics under operational conditions that are similar to those of solid oxide fuel cells, it can additionally be used to study a wide variety of materials, such as high temperature proton conductors. The cell can also be used in many different neutron experiments when a suitable sample holder material is selected. The sample cell system has recently been used to reveal fast dynamic processes in quasi-elastic neutron scattering experiments, which standard probes (such as electrochemical impedance spectroscopy) could not detect. In this work, we outline the design of the sample cell system and present results demonstrating its abilities in high temperature QENS experiments

  20. A new apparatus design for high temperature (up to 950°C) quasi-elastic neutron scattering in a controlled gaseous environment.

    Science.gov (United States)

    al-Wahish, Amal; Armitage, D; al-Binni, U; Hill, B; Mills, R; Jalarvo, N; Santodonato, L; Herwig, K W; Mandrus, D

    2015-09-01

    A design for a sample cell system suitable for high temperature Quasi-Elastic Neutron Scattering (QENS) experiments is presented. The apparatus was developed at the Spallation Neutron Source in Oak Ridge National Lab where it is currently in use. The design provides a special sample cell environment under controlled humid or dry gas flow over a wide range of temperature up to 950 °C. Using such a cell, chemical, dynamical, and physical changes can be studied in situ under various operating conditions. While the cell combined with portable automated gas environment system is especially useful for in situ studies of microscopic dynamics under operational conditions that are similar to those of solid oxide fuel cells, it can additionally be used to study a wide variety of materials, such as high temperature proton conductors. The cell can also be used in many different neutron experiments when a suitable sample holder material is selected. The sample cell system has recently been used to reveal fast dynamic processes in quasi-elastic neutron scattering experiments, which standard probes (such as electrochemical impedance spectroscopy) could not detect. In this work, we outline the design of the sample cell system and present results demonstrating its abilities in high temperature QENS experiments.

  1. Charge retention in deep inelastic electroproduction

    International Nuclear Information System (INIS)

    Erickson, R.; Cohen, I.; Messing, F.; Nordberg, E.; Siemann, R.; Smith-Kintner, J.; Stein, P.; Drews, G.; Gebert, W.; Janata, F.

    1978-11-01

    We have measured the net charge of the forward hadrons electroproduced from a proton target and have observed a rise with increasing x (=Q 2 /2Mv). This effect is expected in the quark-parton model as the electroproduction of hadrons becomes dominated by the fragmentation of u quarks. The data are also consistent with jet models in which a high momentum leading hadron is more likely to be carrying the parent quark than is a slower hadron. (orig.) [de

  2. Probing the partonic structure of exotic particles in hard electroproduction

    International Nuclear Information System (INIS)

    Anikin, I.V.; Pire, B.; Szymanowski, L.; Teryaev, O.V.; Wallon, S.

    2005-01-01

    We argue that the electroproduction of exotic particles is a useful tool for study of their partonic structure. In the case of hybrid mesons, the magnitude of their cross sections shows that they are accessible for measurements in existing electroproduction experiments

  3. Exotic hybrid mesons in hard electroproduction

    CERN Document Server

    Anikin, I V; Szymanowski, L; Teryaev, O V; Wallon, S

    2005-01-01

    We estimate the sizeable cross section for deep exclusive electroproduction of an exotic $J^{PC}=1^{-+}$ hybrid meson in the Bjorken regime. The production amplitude scales like the one for usual meson electroproduction, i.e. as $1/Q^2$. This is due to the non-vanishing leading twist distribution amplitude for the hybrid meson, which may be normalized thanks to its relation to the energy momentum tensor and to the QCD sum rules technique. The hard amplitude is considered up to next-to-leading order in $\\alpha_{S}$ and we explore the consequences of fixing the renormalization scale ambiguity through the BLM procedure. We study the particular case where the hybrid meson decays through a $\\pi\\eta $ meson pair. We discuss the $\\pi\\eta$ generalized distribution amplitude and then calculate the production amplitude for this process. We propose a forward-backward asymmetry in the production of $\\pi$ and $\\eta$ mesons as a signal for the hybrid meson production. We briefly comment on hybrid electroproduction at very ...

  4. Measurement of the spin density matrix for the $\\rho^0$, $K^{*0}(892)$ and $\\phi$ produced in $Z^0$ Decays

    CERN Document Server

    Abreu, P; Adye, T; Alekseev, G D; Alemany, R; Allport, P P; Almehed, S; Amaldi, Ugo; Amato, S; Andersson, P; Andreazza, A; Antilogus, P; Apel, W D; Arnoud, Y; Åsman, B; Augustin, J E; Augustinus, A; Baillon, Paul; Bambade, P; Barão, F; Barbi, M S; Barbiellini, Guido; Bardin, Dimitri Yuri; Barker, G; Baroncelli, A; Bärring, O; Bates, M J; Battaglia, Marco; Baubillier, M; Baudot, J; Becks, K H; Begalli, M; Beillière, P; Belokopytov, Yu A; Benvenuti, Alberto C; Bérat, C; Berggren, M; Bertini, D; Bertrand, D; Besançon, M; Bianchi, F; Bigi, M; Bilenky, S M; Billoir, P; Bizouard, M A; Bloch, D; Blume, M; Bonesini, M; Bonivento, W; Booth, P S L; Borgland, A W; Borisov, G; Bosio, C; Botner, O; Boudinov, E; Bouquet, B; Bourdarios, C; Bowcock, T J V; Bozzo, M; Branchini, P; Brand, K D; Brenke, T; Brenner, R A; Bricman, C; Brown, R C A; Brückman, P; Brunet, J M; Bugge, L; Buran, T; Burgsmüller, T; Buschmann, P; Cabrera, S; Caccia, M; Calvi, M; Camacho-Rozas, A J; Camporesi, T; Canale, V; Canepa, M; Cao, F; Carena, F; Carroll, L; Caso, Carlo; Castillo-Gimenez, M V; Cattai, A; Cavallo, F R; Chabaud, V; Chapkin, M M; Charpentier, P; Chaussard, L; Checchia, P; Chelkov, G A; Chen, M; Chierici, R; Chliapnikov, P V; Chochula, P; Chorowicz, V; Chudoba, J; Cindro, V; Collins, P; Contri, R; Cortina, E; Cosme, G; Cossutti, F; Cowell, J H; Crawley, H B; Crennell, D J; Crosetti, G; Cuevas-Maestro, J; Czellar, S; Dahm, J; D'Almagne, B; Dam, M; Damgaard, G; Dauncey, P D; Davenport, Martyn; Da Silva, W; Deghorain, A; Della Ricca, G; Delpierre, P A; Demaria, N; De Angelis, A; de Boer, Wim; De Brabandere, S; De Clercq, C; La Vaissière, C de; De Lotto, B; De Min, A; De Paula, L S; Dijkstra, H; Di Ciaccio, Lucia; Di Diodato, A; Djannati, A; Dolbeau, J; Doroba, K; Dracos, M; Drees, J; Drees, K A; Dris, M; Durand, J D; Edsall, D M; Ehret, R; Eigen, G; Ekelöf, T J C; Ekspong, Gösta; Elsing, M; Engel, J P; Erzen, B; Espirito-Santo, M C; Falk, E; Fanourakis, G K; Fassouliotis, D; Feindt, Michael; Fenyuk, A; Ferrari, P; Ferrer, A; Fichet, S; Filippas-Tassos, A; Firestone, A; Fischer, P A; Föth, H; Fokitis, E; Fontanelli, F; Formenti, F; Franek, B J; Frodesen, A G; Frühwirth, R; Fulda-Quenzer, F; Fuster, J A; Galloni, A; Gamba, D; Gandelman, M; García, C; García, J; Gaspar, C; Gasparini, U; Gavillet, P; Gazis, E N; Gelé, D; Gerber, J P; Gerdyukov, L N; Gokieli, R; Golob, B; Gonçalves, P; Gopal, Gian P; Gorn, L; Górski, M; Guz, Yu; Gracco, Valerio; Graziani, E; Green, C; Grefrath, A; Gris, P; Grosdidier, G; Grzelak, K; Günther, M; Guy, J; Hahn, F; Hahn, S; Hajduk, Z; Hallgren, A; Hamacher, K; Harris, F J; Hedberg, V; Henriques, R P; Hernández, J J; Herquet, P; Herr, H; Hessing, T L; Heuser, J M; Higón, E; Holmgren, S O; Holt, P J; Holthuizen, D J; Hoorelbeke, S; Houlden, M A; Hrubec, Josef; Huet, K; Hultqvist, K; Jackson, J N; Jacobsson, R; Jalocha, P; Janik, R; Jarlskog, C; Jarlskog, G; Jarry, P; Jean-Marie, B; Johansson, E K; Jönsson, L B; Jönsson, P E; Joram, Christian; Juillot, P; Kaiser, M; Kapusta, F; Karafasoulis, K; Katsanevas, S; Katsoufis, E C; Keränen, R; Khokhlov, Yu A; Khomenko, B A; Khovanskii, N N; King, B J; Kjaer, N J; Klapp, O; Klein, H; Kluit, P M; Knoblauch, D; Kokkinias, P; Koratzinos, M; Korcyl, K; Kostyukhin, V; Kourkoumelis, C; Kuznetsov, O; Krammer, Manfred; Kreuter, C; Kronkvist, I J; Krstic, J; Krumshtein, Z; Krupinski, W; Kubinec, P; Kucewicz, W; Kurvinen, K L; Lacasta, C; Laktineh, I; Lamsa, J; Lanceri, L; Lane, D W; Langefeld, P; Laugier, J P; Lauhakangas, R; Leder, Gerhard; Ledroit, F; Lefébure, V; Legan, C K; Leisos, A; Leitner, R; Lemonne, J; Lenzen, Georg; Lepeltier, V; Lesiak, T; Libby, J; Liko, D; Lipniacka, A; Lippi, I; Lörstad, B; Loken, J G; López, J M; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J N; Maehlum, G; Mahon, J R; Maio, A; Malmgren, T G M; Malychev, V; Mandl, F; Marco, J; Marco, R P; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Martínez-Rivero, C; Martínez-Vidal, F; Martí i García, S; Masik, J; Matorras, F; Matteuzzi, C; Matthiae, Giorgio; Mazzucato, M; McCubbin, M L; McKay, R; McNulty, R; McPherson, G; Medbo, J; Meroni, C; Meyer, S; Meyer, W T; Myagkov, A; Michelotto, M; Migliore, E; Mirabito, L; Mitaroff, Winfried A; Mjörnmark, U; Moa, T; Møller, R; Mönig, K; Monge, M R; Morettini, P; Müller, H; Münich, K; Mulders, M; Mundim, L M; Murray, W J; Muryn, B; Myatt, Gerald; Myklebust, T; Naraghi, F; Navarria, Francesco Luigi; Navas, S; Nawrocki, K; Negri, P; Némécek, S; Neumann, W; Neumeister, N; Nicolaidou, R; Nielsen, B S; Nieuwenhuizen, M; Nikolaenko, V; Nikolenko, M; Niss, P; Nomerotski, A; Normand, Ainsley; Nygren, A; Oberschulte-Beckmann, W; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, Risto; Orazi, G; Österberg, K; Ouraou, A; Paganini, P; Paganoni, M; Pain, R; Palka, H; Papadopoulou, T D; Papageorgiou, K; Pape, L; Parkes, C; Parodi, F; Parzefall, U; Passeri, A; Pegoraro, M; Peralta, L; Pernegger, H; Pernicka, Manfred; Perrotta, A; Petridou, C; Petrolini, A; Phillips, H T; Piana, G; Pierre, F; Pimenta, M; Podobnik, T; Podobrin, O; Pol, M E; Polok, G; Poropat, P; Pozdnyakov, V; Privitera, P; Pukhaeva, N; Pullia, Antonio; Radojicic, D; Ragazzi, S; Rahmani, H; Ratoff, P N; Read, A L; Reale, M; Rebecchi, P; Redaelli, N G; Regler, Meinhard; Reid, D; Reinhardt, R; Renton, P B; Resvanis, L K; Richard, F; Rídky, J; Rinaudo, G; Røhne, O M; Romero, A; Ronchese, P; Roos, L; Rosenberg, E I; Rosinsky, P; Roudeau, Patrick; Rovelli, T; Ruhlmann-Kleider, V; Ruiz, A; Rybicki, K; Saarikko, H; Sacquin, Yu; Sadovskii, A; Sajot, G; Salt, J; Sannino, M; Schneider, H; Schwickerath, U; Schyns, M A E; Sciolla, G; Scuri, F; Seager, P; Sedykh, Yu; Segar, A M; Seitz, A; Sekulin, R L; Serbelloni, L; Shellard, R C; Sheridan, A; Siegrist, P; Silvestre, R; Simonetto, F; Sissakian, A N; Skaali, T B; Smadja, G; Smirnov, N; Smirnova, O G; Smith, G R; Sokolov, A; Solovyanov, O; Sosnowski, R; Souza-Santos, D; Spassoff, Tz; Spiriti, E; Sponholz, P; Squarcia, S; Stampfer, D; Stanescu, C; Stanic, S; Stapnes, Steinar; Stavitski, I; Stevenson, K; Stocchi, A; Strauss, J; Strub, R; Stugu, B; Szczekowski, M; Szeptycka, M; Tabarelli de Fatis, T; Tavernet, J P; Tegenfeldt, F; Terranova, F; Thomas, J; Tilquin, A; Timmermans, J; Tkatchev, L G; Todorov, T; Todorova, S; Toet, D Z; Tomaradze, A G; Tonazzo, A; Tortora, L; Tranströmer, G; Treille, D; Tristram, G; Trombini, A; Troncon, C; Tsirou, A L; Turluer, M L; Tyapkin, I A; Tyndel, M; Tzamarias, S; Überschär, B; Ullaland, O; Uvarov, V; Valenti, G; Vallazza, E; van Apeldoorn, G W; van Dam, P; Van Eldik, J; Van Lysebetten, A; Vassilopoulos, N; Vegni, G; Ventura, L; Venus, W A; Verbeure, F; Verlato, M; Vertogradov, L S; Vilanova, D; Vincent, P; Vitale, L; Vlasov, E; Vodopyanov, A S; Vrba, V; Wahlen, H; Walck, C; Weiser, C; Wetherell, Alan M; Wicke, D; Wickens, J H; Wielers, M; Wilkinson, G R; Williams, W S C; Winter, M; Witek, M; Wlodek, T; Yi, J; Yip, K; Yushchenko, O P; Zach, F; Zaitsev, A; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zevgolatakos, E; Zimin, N I; Zucchelli, G C; Zumerle, G

    1997-01-01

    The spin density matrix elements for the $\\rho^0$, K$^{*0}(892)$ and $\\phi$ produced in hadronic Z$^0$ decays are measured in the DELPHI detector. There is no evidence for spin alignment of the K$^{*0}(892)$ and $\\phi$ in the region $x_p \\leq 0.3$ ($x_p = p/p_{beam}$), where $\\rho_{00} = 0.33 \\pm 0.05$ and $\\rho_{00} = 0.30 \\pm 0.04$, respectively. In the fragmentation region, $x_p \\geq 0.4$, there is some indication for spin alignment of the $\\rho^0$ and K$^{*0}(892)$, since $\\rho_{00} = 0.43 \\pm 0.05$ and $\\rho_{00} = 0.46 \\pm 0.08$, respectively. These values are compared with those found in meson-induced hadronic reactions. For the $\\phi$, $\\rho_{00} = 0.30 \\pm 0.04$ for $x_p \\geq 0.4$ and $0.55 \\pm 0.10$ for $x_p \\geq 0.7$. The off-diagonal spin density matrix element $\\rho_{1-1}$ is consistent with zero in all cases.

  5. A sub-GeV charged-current quasi-elastic νμ cross-section on carbon at SciBooNE

    International Nuclear Information System (INIS)

    Walding, Joseph James

    2010-01-01

    Neutrino-nucleus charged-current quasi-elastic scattering is the signal interaction used by many neutrino oscillation experiments. For muon disappearance studies the signal mode is ν μ n → μp. Modern oscillation experiments, such as T2K, produce neutrino beams with peak beam energies of order a few-GeV. It is therefore vitally important to have accurate measurements of the charged-current quasi-elastic cross-section for future neutrino oscillation experiments. Neutrino-nucleus cross-sections in the few-GeV region are not well understood, with the main uncertainties coming from understanding of the neutrino beam flux and the final state interactions within nuclei. SciBooNE is a sub-GeV neutrino-nucleus cross-section experiment based at Fermilab, Batavia, USA, with the goal to measure neutrino cross-sections with precision of order 5%. SciBooNE took data from June 2007 until August 2008, in total 0.99 x 10 20 and 1.53 x 10 20 protons on target were collected in neutrino and anti-neutrino mode, respectively. In this thesis a ν μ charged-current quasi-elastic (CCQE) cross-section contained within the SciBar sub-detector is presented. A method to tag muons in SciBar was developed and three samples were isolated. An excess in backwards tracks in the one-track sample is observed. A Poisson maximum likelihood is used to extract the CCQE cross-section. The fit was applied using a basic fit parameter model, successfully used to obtain the cross-section in the SciBar-MRD matched CCQE analysis. This method was found to be insufficient in describing the data for the SciBar-contained CCQE analysis. By adding two migration parameters the cross-section was calculated to be 1.004 ± 0.031 (stat) -0.150 +0.101 (sys) x 10 -38 cm 2 /neutron, excluding backwards tracks with a χ 2 = 203.8/76 d.o.f. and 1.083 ± 0.030(stat) -0.177 +0.115 (sys) x 10 -38 cm 2 /neutron, including backwards tracks with a χ 2 = 659.8/133 d.o.f. Only neutrino beam and detector systematics have been

  6. Fusion barrier distributions from capture and quasi-elastic excitation functions measured in reaction 36S, 48Ca, 64Ni+238U

    International Nuclear Information System (INIS)

    Kozulin, E. M.

    2009-01-01

    The subbarrier fusion enhancement in reactions with heavy ions were explained by taking into account coupling between relative motion and intrinsic degrees of freedom of interacting nuclei. The coupling of reaction channels manifests itself in the potential barrier between interacting nuclei giving rise to a distribution of fusion barrier instead of single barrier.Capture and quasi-elastic scattering excitation functions at backward angles were measured for 3 6S , 4 8C a, 6 4N i+2 38U reactions systems at energies close and below the Coulomb barrier (i.e. when the influence of the shell effects on the fusion and characteristics of the decay of the composite system is considerable). Representations of the barrier distributions were extracted from both capture and quasi-elastic data. The experimental representations of barrier distributions were compared with coupled-channel calculations using CCFULL code. The major part of these experiments has been performed at the U-400 accelerator of the Flerov Laboratory of Nuclear Reactions (JINR, Dubna); at the TANDEM-ALPI accelerator of the LNL (INFN, Legnaro, Italy) and at the Accelerator Laboratory of University of Jyvaeskylae (JYFL, Finland) using a time-of-flight spectrometer of fission fragments CORSET (CORrelation SET-up.) The extraction of the masses and Total Kinetic Energy (TKE) of the binary reaction products is based upon the analysis of the two-body velocity In the case of the fusion-fission and quasi-fission processes, the observed peculiarities of mass and energy distributions of the fragments, the ratio between the fusion-fission and quasi-fission cross sections are determined deformations of interaction nuclei and angular momentum carried in the di-nuclear system and the shell structure of the formed fragments. In this work, the high-precision capture and quasi-elastic scattering excitation function data are presented.The influence of projectile and target excitations and nucleon transfer on fusion barrier

  7. Density-dependent Hartree-Fock response functions in quasi-elastic electron scattering on 12C and related sum rules

    International Nuclear Information System (INIS)

    Kohno, M.

    1983-01-01

    We report fully consistent calculations of the longitudinal and transverse response functions of the inclusive quasi-elastic electron scattering on 12 C in the Hartree-Fock approximation. The distorted wave for the outgoing nucleon is constructed from the same non-local Hartree-Fock field as in the ground-state description. Thus the orthogonality and Pauli principle requirements are naturally satisfied. The theoretical prediction, based on the standard density-dependent effective interaction (GO force), shows a good correspondence to the experimental data. Since the calculated response functions automatically satisfy the relevant sum rule, this work illuminates the well-known puzzle concerning the longitudinal part, which remains to be solved. We study the energy-weighted sum rules and discuss effects beyond the mean-field approximation. Meson-exchange-current contributions to the transverse response function are also estimated and found to be small due to cancellations among them. (orig.)

  8. New Insights into the Molecular Dynamics of P3HT:PCBM Bulk Heterojunction: A Time-of-Flight Quasi-Elastic Neutron Scattering Study.

    Science.gov (United States)

    Guilbert, Anne A Y; Zbiri, Mohamed; Jenart, Maud V C; Nielsen, Christian B; Nelson, Jenny

    2016-06-16

    The molecular dynamics of organic semiconductor blend layers are likely to affect the optoelectronic properties and the performance of devices such as solar cells. We study the dynamics (5-50 ps) of the poly(3-hexylthiophene) (P3HT): phenyl-C61-butyric acid methyl ester (PCBM) blend by time-of-flight quasi-elastic neutron scattering, at temperatures in the range 250-360 K, thus spanning the glass transition temperature region of the polymer and the operation temperature of an OPV device. The behavior of the QENS signal provides evidence for the vitrification of P3HT upon blending, especially above the glass transition temperature, and the plasticization of PCBM by P3HT, both dynamics occurring on the picosecond time scale.

  9. Spectroscopy study after quasi-elastic collision in the system 208Pb+232Th at an incident energy of 17 MeV per nucleon

    International Nuclear Information System (INIS)

    Happ, T.

    1989-01-01

    In the present thesis by means of a particle-particle-γ and particle-particle-neutron coincidence experiment γ and neutron spectroscopic studies after quasi-elastic collisions at incident energies far above the Coulomb barrier were performed. For the study of the γ decay by the necessary correction of the Doppler shift the possibility results to study excitations in the projectile and in the target. So in the case of 232 Th beside the observation of the ground state band up to the spin 14 ℎ also a very large number of transitions from vibrational side bands. From the spectra the γ emission probabilities in dependence on the distance of closest approximation were extracted. (orig./HSI) [de

  10. Ratio of spin transfer parameters dt/rt in d(p vector, n vector)pp quasi-elastic scattering

    International Nuclear Information System (INIS)

    Abegg, R.; Green, W.; Greeniaus, L.G.; Miller, C.A.; Bardyopadhyay, D.; Birchall, J.; Davis, C.A.; Davison, N.E.; Page, S.A.; Ramsay, W.D.; van Oers, W.T.H.; Lapointe, C.; Moss, G.A.; Tkachuk, R.R.

    1988-05-01

    The ratio of spin transfer parameters d t /r t for the quasi-elastic process d(p,n)pp has been measured at four energies between 200 and 500 MeV at a neutron scattering angle of 9 degrees. From this, the following values of D t /R t for free np scattering have been deduced: -0.0190 ± 0.0072 (T p = 223 MeV); -0.2328 ± 0.0057 (324 MeV); -0.3731 ± 0.0068 (425 MeV); -0.4892 ± 0.0107 (492 MeV). These values have a noticeable effect on present day phase shift solutions. The magnitude of the ε 1 mixing parameter is reduced and other phase shifts are smoother around 300 MeV. (Author) (17 refs., 2 tabs., 3 figs.)

  11. Using the quasi-elastic pion-proton backscattering at 0.7 GeV/c for studying the Fermi motion in light nuclei

    International Nuclear Information System (INIS)

    Abramov, B.M.; Borodin, Yu.A.; Bulychev, S.A.; Dukhovskoj, I.A.; Krutenkova, A.P.; Kulikov, V.V.; Matsyuk, M.A.; Radkevich, I.A.; Turdakina, E.N.; Khanov, A.I.

    2000-01-01

    In terms of the experiment to study the quasi-elastic pion-nucleon scattering with pulse intensive pulse transfer in nuclei within plane-wave approximation one analyzed proton distributions along the Fermi-pulse for 6 Li, 7 Li, 12 C light nuclei. Model of the Fermi-gas was found to describe the experiment data inadequately in contrast to (e, e') experiments while the oscillation model turned to describe spectrum form quate properly. However, the derived values of the parameters of these distributions are noticeably less than in case of (e, e') experiments. It indicates the weak point of the plane-wave approach and demonstrates the necessity to apply more sophisticated approaches to analyze data [ru

  12. First observation of the decay $D^{0}\\rightarrow K^{-}\\pi^{+}\\mu^{+}\\mu^{-}$ in the $\\rho^{0}$-$\\omega$ region of the dimuon mass spectrum

    CERN Document Server

    Aaij, Roel; Adeva, Bernardo; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassi, Guido; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; d'Argent, Philippe; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Bellee, Violaine; Belloli, Nicoletta; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Billoir, Pierre; Bird, Thomas; Birnkraut, Alex; Bizzeti, Andrea; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Buchanan, Emma; Burr, Christopher; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cavallero, Giovanni; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dall'Occo, Elena; Dalseno, Jeremy; David, Pieter; Davis, Adam; De Aguiar Francisco, Oscar; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Demmer, Moritz; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Di Ruscio, Francesco; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dufour, Laurent; Dujany, Giulio; Dupertuis, Frederic; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fohl, Klaus; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forshaw, Dean Charles; Forty, Roger; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gauld, Rhorry; Gavardi, Laura; Gazzoni, Giulio; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianì, Sebastiana; Gibson, Valerie; Girard, Olivier Göran; Giubega, Lavinia-Helena; Gligorov, V.V.; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadavizadeh, Thomas; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Heister, Arno; Hennessy, Karol; Henrard, Pierre; Henry, Louis; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Humair, Thibaud; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; Jing, Fanfan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kecke, Matthieu; Kelsey, Matthew; Kenyon, Ian; Kenzie, Matthew; Ketel, Tjeerd; Khairullin, Egor; Khanji, Basem; Khurewathanakul, Chitsanu; Kirn, Thomas; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Kozeiha, Mohamad; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Krzemien, Wojciech; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kuonen, Axel Kevin; Kurek, Krzysztof; Kvaratskheliya, Tengiz; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Lemos Cid, Edgar; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Liu, Xuesong; Loh, David; Longstaff, Iain; Lopes, Jose; Lucchesi, Donatella; Lucio Martinez, Miriam; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Lusiani, Alberto; Machefert, Frederic; Maciuc, Florin; Maev, Oleg; Maguire, Kevin; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Marks, Jörg; Martellotti, Giuseppe; Martin, Morgan; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathad, Abhijit; Mathe, Zoltan; Matteuzzi, Clara; Mauri, Andrea; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; Meadows, Brian; Meier, Frank; Meissner, Marco; Melnychuk, Dmytro; Merk, Marcel; Michielin, Emanuele; Milanes, Diego Alejandro; Minard, Marie-Noelle; Mitzel, Dominik Stefan; Molina Rodriguez, Josue; Monroy, Ignacio Alberto; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Dominik; Müller, Janine; Müller, Katharina; Müller, Vanessa; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nandi, Anita; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Osorio Rodrigues, Bruno; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Aranzazu; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Pappenheimer, Cheryl; Parker, William; Parkes, Christopher; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Petridis, Konstantinos; Petrolini, Alessandro; Petruzzo, Marco; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Piucci, Alessio; Playfer, Stephen; Plo Casasus, Maximo; Poikela, Tuomas; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Rachwal, Bartolomiej; Rademacker, Jonas; Rama, Matteo; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Ronayne, John William; Rotondo, Marcello; Rouvinet, Julien; Ruf, Thomas; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santimaria, Marco; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schael, Stefan; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmelzer, Timon; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schubiger, Maxime; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Siddi, Benedetto Gianluca; Silva Coutinho, Rafael; Silva de Oliveira, Luiz Gustavo; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skwarnicki, Tomasz; Smith, Edmund; Smith, Eluned; Smith, Iwan Thomas; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Stefkova, Slavomira; Steinkamp, Olaf; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szumlak, Tomasz; T'Jampens, Stephane; Tayduganov, Andrey; Tekampe, Tobias; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Todd, Jacob; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Trabelsi, Karim; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; van Veghel, Maarten; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Volkov, Vladimir; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Weiden, Andreas; Whitehead, Mark; Wilkinson, Guy; Wilkinson, Michael; Williams, Mark Richard James; Williams, Matthew; Williams, Mike; Williams, Timothy; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xu, Zhirui; Yang, Zhenwei; Yu, Jiesheng; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang; Zhukov, Valery; Zucchelli, Stefano

    2016-06-10

    A study of the decay $D^{0}\\rightarrow K^{-}\\pi^{+}\\mu^{+}\\mu^{-}$ is performed using data collected by the LHCb detector in proton-proton collisions at a centre-of-mass energy of 8 TeV, corresponding to an integrated luminosity of 2.0 fb$^{-1}$. Decay candidates with muon pairs that have an invariant mass in the range 675--875 MeV$/c^2$ are considered. This region is dominated by the $\\rho^{0}$ and $\\omega$ resonances. The branching fraction in this range is measured to be ${\\cal B}$($D^{0}\\rightarrow K^{-}\\pi^{+}\\mu^{+}\\mu^{-}$ ) = $( 4.17 \\pm 0.12(stat) \\pm 0.40(syst) )\\times10^{-6}$. This is the first observation of the decay $D^{0}\\rightarrow K^{-}\\pi^{+}\\mu^{+}\\mu^{-}$. Its branching fraction is consistent with the value expected in the Standard Model.

  13. Regge expansion of a casual spectral function in electroproduction

    International Nuclear Information System (INIS)

    Ahmed, M.A.; Taha, M.O.

    1975-01-01

    The conjecture that a term in the Regge espansion of the Deser-Gilbert-Sudarshan spectral function in electroproduction may identically vanish is investigated. It is shown that this conjecture does not appear to be in agreement with experiment

  14. Low-energy photo- and electroproduction for physical pions

    International Nuclear Information System (INIS)

    MacMullen, J.T.

    1979-02-01

    The Ward identities of current algebra are combined with gauge invariance constraints, on-shell PCAC and the Bjorken limit to obtain the low-energy expressions of the pion photo- and electroproduction invariant amplitudes for physical pions

  15. Adsorption and desorption behaviors of cationic liposome-DNA complexes upon lipofection in inside and outside biomembrane models using a dynamic quasi-elastic laser scattering method.

    Science.gov (United States)

    Uchiyama, Yoshiko; Yui, Hiroharu; Sawada, Tsuguo

    2004-11-01

    The dynamic behaviors of cationic liposome-DNA complexes in inside and outside biomembrane models upon lipofection were investigated using the time-resolved quasi-elastic laser scattering (QELS) method. Inside and outside biomembrane models with similar phospholipid compositions to those in living cells were formed at a tetradecane/phosphate buffered saline (TD/PBS) interface. Cationic liposome-DNA complexes were injected into the buffer subphase, and their adsorption/desorption behaviors at the biomembrane models were monitored through changes in the interfacial tension. We found that the adsorption rate of the complexes increased 2.6 times more in the outside model than in the inside one. The adsorption rate of DNA alone did not show a remarkable difference from one side to the other; however, the adsorption rate of the cationic liposome alone showed a similar tendency to that of the liposome-DNA complex. These results indicated that the difference in lipid composition induced a different dynamic behavior of exogenous biomolecules and that the cationic liposomes played an important role in the faster incorporation of DNA into cells upon lipofection.

  16. On possible contribution of standing wave like spacer dynamics in polymer liquid crystals to quasi-elastic cold neutron scattering spectra

    International Nuclear Information System (INIS)

    Jecl, R.; Cvikl, B.

    1998-01-01

    The quasi-elastic cold neutron incoherent scattering law, QNS, for the assumed case of transversal standing wave type of motion of the linear chain a spacer-of the polyacrylate polymer liquid crystal, based upon the random walk of the particle between two perfectly potential barriers, is derived. The spacer protons are taken to vibrate (within the stationary plane) transversely to the line joining the oxygen atoms in a way where they are all simultaneously displaced in the same direction with amplitudes of the standing wave fundamental mode of the vibration excited. The calculated relevant incoherent scattering law is found to be a non-distinct function of the scattering vector Q, in the sense that the postulated dynamical effect of the spacer protons causes the peak value of the calculated incoherent scattering law, S(Q,ω), to remain constant throughout the experimentally accessible range of the scattering vector Q. It appears that, when the experimental resolution broadening effects is taken into account, the contribution of the postulated dynamical behavior to the measured QNS spectra might be small, particularly so, if dome additional motion of the scatters is present, and consequently the standing wave like spacer dynamics in polymer liquid crystals will be very difficult to be identified uniquely in the quasielastic neutron scattering experiments.(author)

  17. Meaurement of the target single-spin asymmetry in quasi-elastic region from the reaction {sup 3}He{up_arrow}(e,e')

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yawei [Rutgers

    2013-10-01

    A measurement of the inclusive target single-spin asymmetry has been performed using the quasi-elastic {sup 3}He{up_arrow}(e,e') reaction with a vertically polarized {sup 3}He target at Q{sup 2} values of 0.13, 0.46 and 0.97 GeV{sup 2}. This asymmetry vanishes under the one photon exchange assumption. But the interference between two-photon exchange and one-photon exchange gives rise to an imaginary amplitude, so that a non-zero A{sub y} is allowed. The experiment, conducted in Hall A of Jefferson Laboratory in 2009, used two independent spectrometers to simultaneously measure the target single-spin asymmetry. Using the effective polarization approximation, the neutron single-spin asymmetries were extracted from the measured {sup 3}He asymmetries. The measurement is to establish a non-vanishing A{sub y}. Non-zero asymmetries were observed at all Q{sup 2} points, and the overall precision is an order of magnitude improved over the existing proton data. The data provide new constraints on Generalized Parton Distribution (GPD) models and new information on the dynamics of the two-photon exchange process.

  18. Measurement of the $M_A^{QE}$ parameter using multiple quasi-elastic dominated sub-samples in the minos near detector

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, Nathan Samuel [Indiana Univ., Bloomington, IN (United States)

    2011-12-05

    The Main Injector Neutrino Oscillation Search (MINOS) is a two detector, long baseline neutrino oscillation experiment. The MINOS near detector is an ironscintillator tracking/sampling calorimeter and has recorded the world’s largest data set of neutrino interactions in the 0-5 GeV region. This high statistics data set is used to make precision measurements of neutrino interaction cross-sections on iron. The Q2 dependence in charged current quasi-elastic (CCQE) scattering probes the axial and vector structure (form factor) of the nucleon/nuclear target, and nuclear effects in neutrino scattering. Presented here is a study of the MINOS Data that will introduce a method that improves the existing MINOS CCQE analysis. This analysis uses an additional CCQE dominated sub-sample from a different kinematic region to reduce correlations between fit parameters in the existing MINOS CCQE analysis. The measured value of the axial-vector mass is MQE A = 1.312+0.037 -0.038(fit)+0.123 -0.265(syst.) GeV.

  19. Calculation of the RPA response function of nuclei to quasi-elastic electron scattering with a density-dependent NN interaction

    International Nuclear Information System (INIS)

    Caillon, J-C.; Labarsouque, J.

    1997-01-01

    So far, the non-relativistic longitudinal and transverse functions in electron quasi-elastic scattering on the nuclei failed in reproducing satisfactorily the existent experimental data. The calculations including relativistic RPA correlations utilize until now the relativistic Hartree approximation to describe the nuclear matter. But, this provides an incompressibility module two times higher than its experimental value what is an important drawback for the calculation of realistic relativistic RPA correlations. Hence, we have determined the RPA response functions of nuclei by utilising a description of the relativistic nuclear matter leading to an incompressibility module in agreement with the empirical value. To do that we have utilized an interaction in the relativistic Hartree approximation in which we have determined the coupling constants σ-N and ω-N as a function of the density in order to reproduce the saturation curve obtained by a Dirac-Brueckner calculation. The results which we have obtained show that the longitudinal response function and the Coulomb sum generally overestimated when one utilizes the pure relativistic Hartree approximation, are here in good agreement with the experimental data for several nuclei

  20. An Improved Measurement of the Muon Neutrino Charged Current Quasi-Elastic Cross-Section on Hydrocarbon at MINERnuA

    Science.gov (United States)

    Zhang, Dun

    Neutrino interactions in the detectors of long baseline oscillation experiments are analyzed to determine the neutrino flavor and energy spectrum, allowing the neutrino mass ordering and mixing parameters to be determined. For neutrino interactions below the pion production threshold, the dominant reaction is charged current quasi-elastic (CCQE) scattering. Oscillation experiments are made of heavy nuclei so the QE process occurs on nucleons that are embedded in the nuclear environment. Predictions of the QE cross-section suffer from significant uncertainties due to our understanding of that nuclear environment and the way it is probed by the weak interaction. I have developed a new technique to reduce the inelastic background to CCQE process by identifying the "Michel electrons" produced by pions. Additionally an updated neutrino flux was used to extract the cross-section and estimates for some sources of systematic uncertainties have been improved. The measured cross-section is compared to several theoretical models and the effect that the signal definition ("CCQE" vs "CCQE-like") has on the measurement is also explored.

  1. Self and transport diffusivity of CO2 in the metal-organic framework MIL-47(V) explored by quasi-elastic neutron scattering experiments and molecular dynamics simulations.

    Science.gov (United States)

    Salles, Fabrice; Jobic, Hervé; Devic, Thomas; Llewellyn, Philip L; Serre, Christian; Férey, Gérard; Maurin, Guillaume

    2010-01-26

    Quasi-elastic neutron scattering measurements are combined with molecular dynamics simulations to determine the self-diffusivity, corrected diffusivity, and transport diffusivity of CO(2) in the metal-organic framework MIL-47(V) (MIL = Materials Institut Lavoisier) over a wide range of loading. The force field used for describing the host/guest interactions is first validated on the thermodynamics of the MIL-47(V)/CO(2) system, prior to being transferred to the investigations of the dynamics. A decreasing profile is then deduced for D(s) and D(o) whereas D(t) presents a non monotonous evolution with a slight decrease at low loading followed by a sharp increase at higher loading. Such decrease of D(t) which has never been evidenced in any microporous systems comes from the atypical evolution of the thermodynamic correction factor that reaches values below 1 at low loading. This implies that, due to intermolecular interactions, the CO(2) molecules in MIL-47(V) do not behave like an ideal gas. Further, molecular simulations enabled us to elucidate unambiguously a 3D diffusion mechanism within the pores of MIL-47(V).

  2. Exclusive Backward-Angle Omega Meson Electroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Wenliang, Li [Univ. of Regina, Regina, SK (Canada)

    2017-10-01

    Exclusive meson electroproduction at different squared four-momenta of the exchanged virtual photon, Q2 , and at different four-momentum transfers, t and u, can be used to probe QCD's transition from hadronic degrees of freedom at the long distance scale to quark-gluon degrees of freedom at the short distance scale. Backward-angle meson electroproduction was previously ignored, but is anticipated to offer complimentary information to conventional forward-angle meson electroproduction studies on nucleon structure. This work is a pioneering study of backward-angle ω cross sections through the exclusive 1H(e, e'p)ω reaction using the missing mass reconstruction technique. The extracted cross sections are separated into the transverse (T), longitudinal (L), and LT, TT interference terms. The analyzed data were part of experiment E01-004 (Fπ-2), which used 2.6-5.2 GeV electron beams and HMS+SOS spectrometers in Jefferson Lab Hall C. The primary objective was to detect coincidence π in the forward-angle, where the backward-angle omega events were fortuitously detected. The experiment has central Q2 values of 1.60 and 2.45 GeV2 , at W = 2.21 GeV. There was significant coverage in phi and epsilon, which allowed separation of σT,L,LT,TT . The data set has a unique u coverage of -u ~ 0, which corresponds to -t > 4 GeV2 . The separated σT result suggest a flat ~ 1/Q1.33±1.21 dependence, whereas sigma_L seems to hold a stronger 1/Q9.43±6.28 dependence. The σL/σT ratio indicate σT dominance at Q2 = 2.45 GeV2 at the ~90% confidence level. After translating the results into the -t space of the published CLAS data, our data show evidence of a backward-angle omega electroproduction peak at both Q2 settings. Previously, this phenomenon showing both forward and backward-angle peaks was only observed in the meson

  3. Longitudinal Electroproduction of Charged Pions from

    International Nuclear Information System (INIS)

    David Gaskell; Abdellah Ahmidouch; Pawel Ambrozewicz; H. Anklin; John Arrington; K. Assamagan; Steven Avery; Kevin Bailey; Oliver K. Baker; Shelton Beedoe; Elizabeth Beise; Herbert Breuer; D. S. Brown; Roger Carlini; Jinseok Cha; Nicholas Chant; Anthony Cowley; Samuel Danagoulian; D. De Schepper; Jim Dunne; Dipangkar Dutta; Rolf Ent; Liping Gan; Ashot Gasparian; Donald Geesaman; Ron Gilman; Charles Glashausser; Paul Gueye; M. Harvey; O. Hashimoto; Wendy Hinton; G. Hofman; Ceasar Jackson; Hal Jackson; Cynthia Keppel; Ed Kinney; Doug Koltenuk; G. Kyle; Allison Lung; David Mack; D. McKee; Joseph Mitchell; Hamlet Mkrtchyan; B. Mueller; Gabriel Niculescu; Ioana Niculescu; Tom O'Neill; V. Papavassiliou; Dave Potterveld; Juerg Reinhold; Philip Roos; Reyad Sawafta; Ralph Segel; Stepan Stepanyan; Vardan Tadevosyan; T. Takahashi; Liguang Tang; B. Terburg; D. Van Westrum; J. Volmer; T. P. Welch; Stephen Wood; Lulin Yuan; Ben Zeidman; Beni Zihlmann

    2001-01-01

    Separated longitudinal and transverse cross sections for charged pion electroproduction from 1 H, 2 H, and 3 He were measured at Q 2 = 0.4 (GeV/c) 2 for two values of the invariant mass, (bar W) = 1.15 GeV and (bar W) = 1.60 GeV, in a search for a mass dependence which would signal the effect of nuclear pions. This is the first such study that includes recoil momenta significantly above the Fermi surface. The longitudinal cross section, if dominated by the pion-pole process, should be sensitive to nuclear pion currents. Comparisons of the longitudinal cross section target ratios to a quasifree calculation reveal a significant suppression in 3> He at (bar W) = 1.60 GeV. The (bar W) = 1.15 GeV results are consistent with simple estimates of the effect of nuclear pion currents, but are also consistent with pure quasifree production

  4. Exclusive electroproduction of two pions at HERA

    CERN Document Server

    Abramowicz, H.

    2012-01-25

    The exclusive electroproduction of two pions in the mass range 0.4 < M{\\pi}{\\pi} < 2.5 GeV has been studied with the ZEUS detector at HERA using an integrated luminosity of 82 pb-1. The analysis was carried out in the kinematic range of 2 < Q2 < 80 GeV2, 32 < W < 180 GeV and |t| < 0.6 GeV2, where Q2 is the photon virtuality, W is the photon-proton centre-of-mass energy and t is the squared four-momentum transfer at the proton vertex. The two-pion invariant-mass distribution is interpreted in terms of the pion electromagnetic form factor, |F(M{\\pi}{\\pi})|, assuming that the studied mass range includes the contributions of the {\\rho}, {\\rho}' and {\\rho}" vector-meson states. The masses and widths of the resonances were obtained and the Q2 dependence of the cross-section ratios {\\sigma}({\\rho}' \\rightarrow {\\pi}{\\pi})/{\\sigma}({\\rho}) and {\\sigma}({\\rho}" \\rightarrow {\\pi}{\\pi})/{\\sigma}({\\rho}) was extracted. The pion form factor obtained in the present analysis is compared to that obtained...

  5. Exclusive electroproduction of two pions at HERA

    International Nuclear Information System (INIS)

    Abramowicz, H.; Ashery, D.; Gueta, O.; Gurvich, E.; Ingbir, R.; Kananov, S.; Levy, A.; Stern, A.

    2012-01-01

    The exclusive electroproduction of two pions in the mass range 0.4 ππ -1 . The analysis was carried out in the kinematic range of 2 2 2 , 32 2 , where Q 2 is the photon virtuality, W is the photon-proton centre-of-mass energy and t is the squared four-momentum transfer at the proton vertex. The two-pion invariant-mass distribution is interpreted in terms of the pion electromagnetic form factor, vertical stroke F(M ππ ) vertical stroke, assuming that the studied mass range includes the contributions of the ρ, ρ' and ρ'' vector-meson states. The masses and widths of the resonances were obtained and the Q 2 dependence of the cross-section ratios σ(ρ'→ππ)/ σ(ρ) and σ(ρ''→ππ)/ σ(ρ) was extracted. The pion form factor obtained in the present analysis is compared to that obtained in e + e - →π + π - . (orig.)

  6. Exclusive electroproduction of two pions at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Abramowicz, H. [Tel Aviv Univ. (Israel). School of Physics; Max Planck Institute for Physics, Munich (Germany); Abt, I. [Max Planck Institute for Physics, Munich (Germany); Adamczyk, L. [AGH-Univ. of Science and Technology, Krakow (PL). Faculty of Physics and Applied Computer Science] (and others)

    2011-11-15

    The exclusive electroproduction of two pions in the mass range 0.4< M{sub {pi}}{sub {pi}} <2.5 GeV has been studied with the ZEUS detector at HERA using an integrated luminosity of 82 pb{sup -1}. The analysis was carried out in the kinematic range of 2< Q{sup 2}<80 GeV{sup 2}, 32

  7. Exploring Hadron Structure Through Exclusive Kaon Electroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Carmignotto, Marco A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2017-04-01

    The kaon electroproduction cross section was extracted from data from the E93-018 and the E01-004 (FPI-2) experiments taken at the Thomas Jefferson National Accelerator Facility in the p(e,e'K+)Λ channel. The cross section was fully separated into longitudinal, transverse, and two interference components at four-momentum transfers Q2 of 1.0 (GeV/c)2 (with center of mass energy W=1.81 GeV), 1.36 and 2.07 (GeV/c)2 (W=2.31 GeV). The kaon form factor (FK) was extracted from the longitudinal cross section in these kinematics using the Regge model by Vanderhaeghen, Guidal, and Laget. Results show FK to be systematically lower than the empirical monopole form, although still compatible with this form within the estimated uncertainties. The resulting kaon form factor values were combined with the world pion and kaon form factor data to extract the transverse change densities of the pion and kaon. These were compared to that of the proton, showing a possible experimental glimpse of the transition between the proton core and the meson cloud in terms of transverse densities.

  8. Pion photo- and electroproduction in relativistic baryon ChPT

    Directory of Open Access Journals (Sweden)

    Tiator Lothar

    2014-06-01

    Full Text Available We present a calculation of pion photo- and electroproduction in manifestly Lorentz-invariant baryon chiral perturbation theory up to and including order q4. We fix the low-energy constants by fitting experimental data in all available reaction channels. Our results can be accessed via a web interface, the so-called chiral MAID.

  9. SLAC workshop on high energy electroproduction and spin physics

    International Nuclear Information System (INIS)

    1992-01-01

    These Proceedings contain copies of the transparencies presented at the Workshop on High Energy Electroproduction and Spin Physics held at SLAC on February 5--8, 1992. The purpose of this Workshop was to bring people together to discuss the possibilities for new experiments using the SLAC high intensity electron and photon beams and the facilities of End Station A

  10. {pi}{eta} pair hard electroproduction and exotic hybrid mesons

    Energy Technology Data Exchange (ETDEWEB)

    Anikin, I.V. [LPT, Universite Paris-Sud, 91405-Orsay, France, UMR 8627 du CNRS (France); BLTP, JINR, 141980 Dubna (Russian Federation); CPHT, Ecole Polytechnique, 91128 Palaiseau, France, UMR 7644 du CNRS (France); Pire, B. [CPHT, Ecole Polytechnique, 91128 Palaiseau, France, UMR 7644 du CNRS (France); Szymanowski, L. [Soltan Institute for Nuclear Studies, Warsaw (Poland) and Univ. de Liege, B-4000 Liege (Belgium); Teryaev, O.V. [BLTP, JINR, 141980 Dubna (Russian Federation); Wallon, S. [LPT, Universite Paris-Sud, 91405-Orsay, France, UMR 8627 du CNRS (France)

    2005-06-13

    We show that hard electroproduction is a promising way to study exotic hybrid mesons, in particular through the hybrid decay channel H->{pi}{eta}. We discuss the {pi}{eta} generalized distribution amplitude, calculate the production amplitude and propose a forward-backward asymmetry as a signal for the hybrid meson production.

  11. πη pair hard electroproduction and exotic hybrid mesons

    International Nuclear Information System (INIS)

    Anikin, I.V.; Pire, B.; Szymanowski, L.; Teryaev, O.V.; Wallon, S.

    2005-01-01

    We show that hard electroproduction is a promising way to study exotic hybrid mesons, in particular through the hybrid decay channel H->πη. We discuss the πη generalized distribution amplitude, calculate the production amplitude and propose a forward-backward asymmetry as a signal for the hybrid meson production

  12. Strange hadronic physics in electroproduction experiments at the Mainz Microtron

    Czech Academy of Sciences Publication Activity Database

    Achenbach, P.; Esser, A.; Gayoso, C. A.; Böhm, R.; Borodina, O.; Bosnar, D.; Bozkurt, V.; Bydžovský, Petr; Debenjak, L.; Distler, M. O.; Friscic, I.; Fujii, Y.; Gogami, T.; Gomez, M.R.; Hashimoto, O.; Hirose, S.; Kim, E.; Margaryan, A.; Merkel, H.; Müller, U.; Nagao, S.; Nakamura, S. N.; Pochodzalla, J.; Rappold, C.; Reinhold, J.; Saito, T.; Lorente, A.S.; Majos, S. S.; Schlimme, B. S.; Schoth, M.; Schulz, F.; Sfienti, C.; Sirca, S.; Tang, L.; Thiel, M.; Tsukada, K.

    2012-01-01

    Roč. 881, 5/6 (2012), s. 187-198 ISSN 0375-9474 R&D Projects: GA MŠk(CZ) LG11005 Institutional support: RVO:61389005 Keywords : strangeness reactions * Kaon electroproduction * missing mass spectroscopy * hypernuclei * decay-pion spectroscopy Subject RIV: BE - Theoretical Physics Impact factor: 1.525, year: 2012

  13. Spin O decay angular distribution for interfering mesons in electroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Funsten, H.; Gilfoyle, G.

    1994-04-01

    Self analyzing meson electroproduction experiments are currently being planned for the CEBAF CLAS detector. These experiments deduce the spin polarization of outgoing unstable spin s (?)0 mesons from their decay angular distribution, W({theta},{psi}). The large angular acceptance of the CLAS detector permits kinematic tracking of a sufficient number of these events to accurately determine electroproduction amplitudes from the deduced polarization. Maximum polarization information is obtained from W({theta},{psi}) for decay into spin 0 daughters. The helicity of the decaying meson is transferred to the daughter`s relative orbital angular momentum m-projection; none is {open_quotes}absorbed{close_quotes} into daughter helicities. The decaying meson`s helicity maximally appears in W({theta},{psi}). W({theta},{psi}) for spin 0 daughters has been derived for (1) vector meson electroproduction and (2) general interfering mesons produced by incident pions. This paper derives W({theta},{psi}) for electroproduction of two interfering mesons that decay into spin 0 daughters. An application is made to the case of interfering scalar and vector mesons. The derivation is an extension of work by Schil using the general decay formalism of Martin. The expressions can be easily extended to the case of N interfering mesons since interference occurs pairwise in the observable W ({theta},{psi}), a quadratic function of the meson amplitudes. The derivation uses the virtual photon density matrix of Schil which is transformed by a meson electroproduction transition operator, T. The resulting density matrix for the interfering mesons is then converted into a corresponding statistical tensor and contracted into the efficiency tensor for spin 0 daughters.

  14. Precision measurement of quasi-elastic transverse and longitudinal response functions in the range 0.55 GeV/c lte |q-right arrow| lte 1.0 GeV/c

    Energy Technology Data Exchange (ETDEWEB)

    Atac, Hamza [Temple University, Philadelphia, PA

    2017-12-01

    The Coulomb Sum is defined by the quasi-elastic nucleon knock-out process and it is the integration of the longitudinal response function over the energy loss of the incident electron. The Coulomb sum goes to the total charge at large q. The existing measurements of the Coulomb Sum Rule show disagreement with the theoretical calculations for the medium and heavy nuclei. To find the reason behind the disagreement might answer the question of whether the properties of the nucleons are affected by the nuclear medium or not. In order to determine the Coulomb Sum in nuclei, a precision measurement of inclusive electron scattering in the quasi-elastic region was performed at the Thomas Jefferson National Accelerator Facility. Incident electrons with energies ranging from 0.4 GeV to 4 GeV scattered off 4He,12C,56Fe and 208Pb nuclei at four scattering angles (15 deg.; 60 deg.; 90 deg.; 120 deg.) and scattered energies ranging from 0.1 GeV to 4 GeV. The Born cross sections were extracted for the Left High Resolution Spectrometer (LHRS) and the Right High Resolution Spectrometer 56Fe data. The Rosenbluth separation was performed to extract the transverse and longitudinal response functions at 650 MeV three-momentum transfer. The preliminary results of the longitudinal and transverse functions were extracted for 56Fe target at 650 MeV three-momentum transfer.

  15. Measurement of the Muon Neutrino Double-Differential Charged Current Quasi-Elastic Like Cross Section on a Hydrocarbon Target at Ev ~ 3.5 GeV

    Energy Technology Data Exchange (ETDEWEB)

    Hurtado Anampa, Kenyi Paolo [Rio de Janeiro, CBPF

    2016-01-01

    The MINERvA Experiment (Main Injector Experiment v ₋ A interaction) [1] is a highly segmented detector of neutrinos, able to record events with high precision (over than thirteen million event in a four year run), using the NuMI Beam (Neutrino Main Injector) at the Fermi National Accelerator Laboratory [2]. This thesis presents a measurement of the Charged Current Quasi-Elastic Like1 vμ interaction on polystyrene scintillator (CH) in the MINERvA experiment with neutrino energies between 1.5 and 10 GeV. We use data taken between2 March 2010 and April 2012. The interactions were selected by requiring a negative muon, a reconstructed and identified proton, no michel electrons in the final state (in order to get rid of soft pions decaying) and a low calorimetric recoil energy away from the interaction vertex. The analysis is performed on 66,214 quasi-elastic like event candidates in the detectors tracker region with an estimated purity of 74%. The final measurement reported is a double differential cross sections in terms of the muon longitudinal and transversal momentum observables.

  16. Coherent π0 electroproduction on the deuteron at threshold

    International Nuclear Information System (INIS)

    Jeon, B.K.; Sato, T.; Ohtsubo, H.

    1989-01-01

    We studied the effect of the exchange current on the longitudinal form factor of neutral pion electroproduction. As a result, we obtained a large effect of the exchange current on pion production at threshold with a momentum transfer of 2-3 fm -1 . This reaction may serve as a clear test of the exchange current, which is related to the exchange axial-charge. (orig.)

  17. Measurement of the νμ Charged Current π+ to Quasi-Elastic Cross Section Ratio on Mineral Oil in a 0.8 GeV Neutrino Beam

    International Nuclear Information System (INIS)

    Linden, Steven K.

    2011-01-01

    Charged current single pion production (CCπ + ) and charged current quasi-elastic scattering (CCQE) are the most abundant interaction types for neutrinos at energies around 1 GeV, a region of great interest to oscillation experiments. The cross-sections for these processes, however, are not well understood in this energy range. This dissertation presents a measurement of the ratio of CCπ + to CCQE cross-sections for muon neutrinos on mineral oil (CH 2 ) in the MiniBooNE experiment. The measurement is presented here both with and without corrections for hadronic re-interactions in the target nucleus and is given as a function of neutrino energy in the range 0.4 GeV ν + events collected in MiniBooNE, and with a fractional uncertainty of roughly 11% in the region of highest statistics, this measurement represents a dramatic improvement in statistics and precision over previous CCπ + and CCQE measurements.

  18. Precise Extraction of the Neutron Magnetic Form Factor from Quasi-elastic 3He(pol)(e(pol),e') at Q2 = 0.1-0.6 (GeV/c)2

    International Nuclear Information System (INIS)

    Jens-ole Hansen; Brian Anderson; Leonard Auerbach; Todd Averett; William Bertozzi; Tim Black; John Calarco; Lawrence Cardman; Gordon Cates; Zhengwei Chai; Jiang-Ping Chen; Seonho Choi; Eugene Chudakov; Steve Churchwell; G Corrado; Christopher Crawford; Daniel Dale; Alexandre Deur; Pibero Djawotho; Dipangkar Dutta; John Finn; Haiyan Gao; Ronald Gilman; Oleksandr Glamazdin; Charles Glashausser; Walter Gloeckle; Jacek Golak; Javier Gomez; Viktor Gorbenko; F. Hersman; Douglas Higinbotham; Richard Holmes; Calvin Howell; Emlyn Hughes; Thomas Humensky; Sebastien Incerti; Piotr Zolnierczuk; Cornelis De Jager; John Jensen; Xiaodong Jiang; Cathleen Jones; Mark Jones; R Kahl; H Kamada; A Kievsky; Ioannis Kominis; Wolfgang Korsch; Kevin Kramer; Gerfried Kumbartzki; Michael Kuss; Enkeleida Lakuriqi; Meihua Liang; Nilanga Liyanage; John LeRose; Sergey Malov; Demetrius Margaziotis; Jeffery Martin; Kathy McCormick; Robert McKeown; Kevin McIlhany; Zein-Eddine Meziani; Robert Michaels; Greg Miller; Joseph Mitchell; Sirish Nanda; Emanuele Pace; Tina Pavlin; Gerassimos Petratos; Roman Pomatsalyuk; David Pripstein; David Prout; Ronald Ransome; Yves Roblin; Marat Rvachev; Giovanni Salme; Michael Schnee; Charles Seely; Taeksu Shin; Karl Slifer; Paul Souder; Steffen Strauch; Riad Suleiman; Mark Sutter; Bryan Tipton; Luminita Todor; M Viviani; Branislav Vlahovic; John Watson; Claude Williamson; H Witala; Bogdan Wojtsekhowski; Feng Xiong; Wang Xu; Jen-chuan Yeh

    2006-01-01

    We have measured the transverse asymmetry A T' in the quasi-elastic 3 /rvec He/(/rvec e/,e') process with high precision at Q 2 -values from 0.1 to 0.6 (GeV/c) 2 . The neutron magnetic form factor G M n was extracted at Q 2 -values of 0.1 and 0.2 (GeV/c) 2 using a non-relativistic Faddeev calculation which includes both final-state interactions (FSI) and meson-exchange currents (MEC). Theoretical uncertainties due to the FSI and MEC effects were constrained with a precision measurement of the spin-dependent asymmetry in the threshold region of 3 /rvec He/(/rvec e/,e'). We also extracted the neutron magnetic form factor G M n at Q 2 -values of 0.3 to 0.6 (GeV/c) 2 based on Plane Wave Impulse Approximation calculations

  19. Hard exclusive pion electroproduction at backward angles with CLAS

    Science.gov (United States)

    Park, K.; Guidal, M.; Gothe, R. W.; Pire, B.; Semenov-Tian-Shansky, K.; Laget, J.-M.; Adhikari, K. P.; Adhikari, S.; Akbar, Z.; Avakian, H.; Ball, J.; Balossino, I.; Baltzell, N. A.; Barion, L.; Battaglieri, M.; Bedlinskiy, I.; Biselli, A. S.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Cao, F. T.; Carman, D. S.; Celentano, A.; Charles, G.; Chetry, T.; Ciullo, G.; Clark, L.; Cole, P. L.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Defurne, M.; Deur, A.; Djalali, C.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fersch, R.; Filippi, A.; Garçon, M.; Ghandilyan, Y.; Gilfoyle, G. P.; Girod, F. X.; Golovatch, E.; Griffioen, K. A.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Harrison, N.; Hattawy, M.; Heddle, D.; Hicks, K.; Holtrop, M.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Johnston, S.; Joo, K.; Kabir, M. L.; Keller, D.; Khachatryan, G.; Khachatryan, M.; Khandaker, M.; Kim, W.; Klein, F. J.; Kubarovsky, V.; Kuhn, S. E.; Lanza, L.; Livingston, K.; MacGregor, I. J. D.; Markov, N.; McKinnon, B.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Munoz Camacho, C.; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Osipenko, M.; Paolone, M.; Paremuzyan, R.; Pasyuk, E.; Phelps, W.; Pogorelko, O.; Poudel, J.; Price, J. W.; Prok, Y.; Protopopescu, D.; Ripani, M.; Rizzo, A.; Rossi, P.; Sabatié, F.; Salgado, C.; Schumacher, R. A.; Sharabian, Y.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Tan, J. A.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Wei, X.; Zachariou, N.; Zhang, J.

    2018-05-01

    We report on the first measurement of cross sections for exclusive deeply virtual pion electroproduction off the proton, ep →e‧ nπ+, above the resonance region at backward pion center-of-mass angles. The φπ* -dependent cross sections were measured, from which we extracted three combinations of structure functions of the proton. Our results are compatible with calculations based on nucleon-to-pion transition distribution amplitudes (TDAs). These non-perturbative objects are defined as matrix elements of three-quark-light-cone-operators and characterize partonic correlations with a particular emphasis on baryon charge distribution inside a nucleon.

  20. Electroproduction of pseudoscalar mesons at large transverse momenta

    Energy Technology Data Exchange (ETDEWEB)

    Domokos, G.; Kovesi-Domokos, S.; Yunn, B. C.

    1973-07-15

    Inclusive electroproduction of spinless (pseudoscalar) mesons at large transverse momenta is studied in the framework of local scale invariance. Scaling laws are established for the structure iunctions and approximate analytic expressions are derived for the scaling functions. It is predicted that the cross section decreases essentially according to a power law as a function of the transverse momentum of the observed meson, similarly to hadronic cross sections. The production rate of heavy mesons is found to rise slowly with the laboratory energy of the virtual photon. (auth)

  1. Pion Photo- and Electroproduction and the Partially Conserved Axial Current

    International Nuclear Information System (INIS)

    Haberzettl, Helmut

    2000-01-01

    The relevance of the axial current for pion production processes off the nucleon with real or virtual photons is revisited. Employing the hypothesis of a partially conserved axial current (PCAC), it is shown that, when all of the relevant contributions are taken into account, PCAC does not provide any additional constraint for threshold production processes that goes beyond the Goldberger-Treiman relation. In particular, it is shown that pion electroproduction processes at threshold cannot be used to extract any information regarding the weak axial form factor. The relationships found in previous investigations are seen to be an accident of the approximations usually made in this context

  2. Rosenbluth separation of the $\\pi^0$ electroproduction cross section

    OpenAIRE

    Defurne, M.; Mazouz, M.; Albataineh, H.; Allada, K.; Aniol, K. A.; Bellini, V.; Benali, M.; Boeglin, W.; Bertin, P.; Brossard, M.; Camsonne, A.; Canan, M.; Chandavar, S.; Chen, C.; Chen, J. -P.

    2016-01-01

    We present deeply virtual $\\pi^0$ electroproduction cross-section measurements at $x_B$=0.36 and three different $Q^2$--values ranging from 1.5 to 2 GeV$^2$, obtained from experiment E07-007 that ran in the Hall A at Jefferson Lab. The Rosenbluth technique was used to separate the longitudinal and transverse responses. Results demonstrate that the cross section is dominated by its transverse component, and thus is far from the asymptotic limit predicted by perturbative Quantum Chromodynamics....

  3. Studies of nucleon resonance structure in exclusive meson electroproduction

    International Nuclear Information System (INIS)

    Aznauryan, I.G.; Bashir, A.; Braun, V.M.

    2013-01-01

    Studies of the structure of excited baryons are key factors to the N* program at Jefferson Lab (JLab). Within the first year of data taking with the Hall B CLAS12 detector following the 12 GeV upgrade, a dedicated experiment will aim to extract the N* electrocouplings at high photon virtualities Q 2 . This experiment will allow exploration of the structure of N* resonances at the highest photon virtualities ever achieved, with a kinematic reach up to Q 2 = 12 GeV 2 . This high-Q 2 reach will make it possible to probe the excited nucleon structures at distance scales ranging from where effective degrees of freedom, such as constituent quarks, are dominant through the transition to where nearly massless bare-quark degrees of freedom are relevant. In this document, we present a detailed description of the physics that can be addressed through N* structure studies in exclusive meson electroproduction. The discussion includes recent advances in reaction theory for extracting N* electrocouplings from meson electroproduction off protons, along with Quantum Chromodynamics (QCD)-based approaches to the theoretical interpretation of these fundamental quantities. This program will afford access to the dynamics of the nonperturbative strong interaction responsible for resonance formation, and will be crucial in understanding the nature of confinement and dynamical chiral symmetry breaking in baryons, and how excited nucleons emerge from QCD. (author)

  4. Neutral Pion Electroproduction in the Δ Resonance Region

    Energy Technology Data Exchange (ETDEWEB)

    Villano, Anthony [Rensselaer Polytechnic Inst., Troy, NY (United States)

    2007-11-01

    The electroproduction of baryon resonances at high Q2 is examined. Analysis focuses on the Δ(1232) resonance via exclusive pseudoscalar meson production of π0 particles. Differential cross sections are extracted for exclusive π0 electroproduction. In the central invariant mass (W) region the cross sections are used to extract resonant multipole amplitudes. In particular, the ratio of the electric quadrupole to magnetic dipole amplitudes (E2/M1) will be discussed for the Δ(1232) resonance. The transition to pQCD is discussed in terms of E2/M1 and other multipoles. The helicity amplitude A3/2 can be used as a baryon helicity conservation meter in this context and will be discussed. The fast shrinking of the resonant contribution in the Δ region is observed at this high momentum transfer. Apart from the observables related to pQCD scaling, the transition form factor G$*\\atop{M}$ is extracted along with the scalar to magnetic dipole ratio C2/M1.

  5. Electroproduction of pseudoscalar mesons above the resonance region

    Energy Technology Data Exchange (ETDEWEB)

    Niczyporuk, B.B. [Continuous Electron beam Accelerator Facility, Newport News, VA (United States)

    1994-04-01

    In this paper, the author has revisited twenty year old data considering the progress achieved in related fields. To make further progress in our understanding of strong interactions, one needs much better quality of exclusive electroproduction data. A measurement of the differential cross section {sigma}(t, W, Q{sup 2}) for the reactions e{sup {minus}} + p {r_arrow} e{sup {minus}} + {pi}{sup +}(K{sup +}) + n({Lambda}{degrees}) at a beam energy of {ge} 4 GeV is proposed. Data will be collected simultaneously for both reactions using the CLAS detector at CEBAF in the following kinematical region: Q{sup 2} > 1 GeV{sup 2} and W > 2 GeV. One of the most interesting aspects of electroproduction is that it can be used to measure photoproduction amplitudes as functions of the photon mass squared Q{sup 2} and momentum transfer t. Emphasis is given to measuring the differential cross sections for t {approximately} m{sup 2}{sub {pi},{kappa}}. Above the resonance region (W > 2 GeV), the cross section is dominated by the amplitudes for scalar photons. Measured angular distributions of produced mesons will be used to estimate the contribution of various amplitudes to the cross sections. High statistics and good quality data collected simultaneously using a large acceptance detector will improve our understanding of nucleon structure as well as the hadronic properties of the photon.

  6. Rosenbluth Separation of the π^{0} Electroproduction Cross Section.

    Science.gov (United States)

    Defurne, M; Mazouz, M; Ahmed, Z; Albataineh, H; Allada, K; Aniol, K A; Bellini, V; Benali, M; Boeglin, W; Bertin, P; Brossard, M; Camsonne, A; Canan, M; Chandavar, S; Chen, C; Chen, J-P; de Jager, C W; de Leo, R; Desnault, C; Deur, A; El Fassi, L; Ent, R; Flay, D; Friend, M; Fuchey, E; Frullani, S; Garibaldi, F; Gaskell, D; Giusa, A; Glamazdin, O; Golge, S; Gomez, J; Hansen, O; Higinbotham, D; Holmstrom, T; Horn, T; Huang, J; Huang, M; Huber, G M; Hyde, C E; Iqbal, S; Itard, F; Kang, Ho; Kang, Hy; Kelleher, A; Keppel, C; Koirala, S; Korover, I; LeRose, J J; Lindgren, R; Long, E; Magne, M; Mammei, J; Margaziotis, D J; Markowitz, P; Martí Jiménez-Argüello, A; Meddi, F; Meekins, D; Michaels, R; Mihovilovic, M; Muangma, N; Muñoz Camacho, C; Nadel-Turonski, P; Nuruzzaman, N; Paremuzyan, R; Puckett, A; Punjabi, V; Qiang, Y; Rakhman, A; Rashad, M N H; Riordan, S; Roche, J; Russo, G; Sabatié, F; Saenboonruang, K; Saha, A; Sawatzky, B; Selvy, L; Shahinyan, A; Sirca, S; Solvignon, P; Sperduto, M L; Subedi, R; Sulkosky, V; Sutera, C; Tobias, W A; Urciuoli, G M; Wang, D; Wojtsekhowski, B; Yao, H; Ye, Z; Zana, L; Zhan, X; Zhang, J; Zhao, B; Zhao, Z; Zheng, X; Zhu, P

    2016-12-23

    We present deeply virtual π^{0} electroproduction cross-section measurements at x_{B}=0.36 and three different Q^{2} values ranging from 1.5 to 2  GeV^{2}, obtained from Jefferson Lab Hall A experiment E07-007. The Rosenbluth technique is used to separate the longitudinal and transverse responses. Results demonstrate that the cross section is dominated by its transverse component and, thus, is far from the asymptotic limit predicted by perturbative quantum chromodynamics. Nonetheless, an indication of a nonzero longitudinal contribution is provided by the measured interference term σ_{LT}. Results are compared with several models based on the leading-twist approach of generalized parton distributions (GPDs). In particular, a fair agreement is obtained with models in which the scattering amplitude includes convolution terms of chiral-odd (transversity) GPDs of the nucleon with the twist-3 pion distribution amplitude. This experiment, together with previous extensive unseparated measurements, provides strong support to the exciting idea that transversity GPDs can be accessed via neutral pion electroproduction in the high-Q^{2} regime.

  7. Rosenbluth Separation of the π0 Electroproduction Cross Section

    Science.gov (United States)

    Defurne, M.; Mazouz, M.; Ahmed, Z.; Albataineh, H.; Allada, K.; Aniol, K. A.; Bellini, V.; Benali, M.; Boeglin, W.; Bertin, P.; Brossard, M.; Camsonne, A.; Canan, M.; Chandavar, S.; Chen, C.; Chen, J.-P.; de Jager, C. W.; de Leo, R.; Desnault, C.; Deur, A.; El Fassi, L.; Ent, R.; Flay, D.; Friend, M.; Fuchey, E.; Frullani, S.; Garibaldi, F.; Gaskell, D.; Giusa, A.; Glamazdin, O.; Golge, S.; Gomez, J.; Hansen, O.; Higinbotham, D.; Holmstrom, T.; Horn, T.; Huang, J.; Huang, M.; Huber, G. M.; Hyde, C. E.; Iqbal, S.; Itard, F.; Kang, Ho.; Kang, Hy.; Kelleher, A.; Keppel, C.; Koirala, S.; Korover, I.; LeRose, J. J.; Lindgren, R.; Long, E.; Magne, M.; Mammei, J.; Margaziotis, D. J.; Markowitz, P.; Martí Jiménez-Argüello, A.; Meddi, F.; Meekins, D.; Michaels, R.; Mihovilovic, M.; Muangma, N.; Muñoz Camacho, C.; Nadel-Turonski, P.; Nuruzzaman, N.; Paremuzyan, R.; Puckett, A.; Punjabi, V.; Qiang, Y.; Rakhman, A.; Rashad, M. N. H.; Riordan, S.; Roche, J.; Russo, G.; Sabatié, F.; Saenboonruang, K.; Saha, A.; Sawatzky, B.; Selvy, L.; Shahinyan, A.; Sirca, S.; Solvignon, P.; Sperduto, M. L.; Subedi, R.; Sulkosky, V.; Sutera, C.; Tobias, W. A.; Urciuoli, G. M.; Wang, D.; Wojtsekhowski, B.; Yao, H.; Ye, Z.; Zana, L.; Zhan, X.; Zhang, J.; Zhao, B.; Zhao, Z.; Zheng, X.; Zhu, P.; Jefferson Lab Hall A Collaboration

    2016-12-01

    We present deeply virtual π0 electroproduction cross-section measurements at xB=0.36 and three different Q2 values ranging from 1.5 to 2 GeV 2 , obtained from Jefferson Lab Hall A experiment E07-007. The Rosenbluth technique is used to separate the longitudinal and transverse responses. Results demonstrate that the cross section is dominated by its transverse component and, thus, is far from the asymptotic limit predicted by perturbative quantum chromodynamics. Nonetheless, an indication of a nonzero longitudinal contribution is provided by the measured interference term σL T. Results are compared with several models based on the leading-twist approach of generalized parton distributions (GPDs). In particular, a fair agreement is obtained with models in which the scattering amplitude includes convolution terms of chiral-odd (transversity) GPDs of the nucleon with the twist-3 pion distribution amplitude. This experiment, together with previous extensive unseparated measurements, provides strong support to the exciting idea that transversity GPDs can be accessed via neutral pion electroproduction in the high-Q2 regime.

  8. First observation of the Λ(1405) line shape in electroproduction

    Science.gov (United States)

    Lu, H. Y.; Schumacher, R. A.; Adhikari, K. P.; Adikaram, D.; Aghasyan, M.; Amaryan, M. J.; Pereira, S. Anefalos; Ball, J.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Cole, P. L.; Collins, P.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Doughty, D.; Dupre, R.; Egiyan, H.; Alaoui, A. El; Fassi, L. El; Eugenio, P.; Fedotov, G.; Fegan, S.; Fleming, J. A.; Gabrielyan, M.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Harrison, N.; Heddle, D.; Hicks, K.; Ho, D.; Holtrop, M.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jo, H. S.; Joo, K.; Keller, D.; Khandaker, M.; Kim, W.; Klein, A.; Klein, F. J.; Koirala, S.; Kubarovsky, A.; Kubarovsky, V.; Kuleshov, S. V.; Lewis, S.; Livingston, K.; MacGregor, I. J. D.; Martinez, D.; Mayer, M.; McKinnon, B.; Meyer, C. A.; Mineeva, T.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Moriya, K.; Moutarde, H.; Munevar, E.; Camacho, C. Munoz; Nadel-Turonski, P.; Nepali, C. S.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Pappalardo, L. L.; Paremuzyan, R.; Park, K.; Park, S.; Pasyuk, E.; Peng, P.; Phelps, E.; Phillips, J. J.; Pisano, S.; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Rimal, D.; Ripani, M.; Rosner, G.; Rossi, P.; Sabatié, F.; Saini, M. S.; Salgado, C.; Schott, D.; Seder, E.; Seraydaryan, H.; Sharabian, Y. G.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Stepanyan, S. S.; Stoler, P.; Strauch, S.; Taiuti, M.; Tang, W.; Tian, Ye; Tkachenko, S.; Torayev, B.; Vernarsky, B.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Weygand, D. P.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.

    2013-10-01

    We report the first observation of the line shape of the Λ(1405) from electroproduction, and show that it is not a simple Breit-Wigner resonance. Electroproduction of K+Λ(1405) off the proton was studied by using data from CLAS at Jefferson Lab in the range 1.0

  9. A Precision Measurement of the Transverse Asymmetry AT from Quasi-elastic 3He(e,e') process, and the Neutron Magnetic Form Factor GNM at low Q2

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Wang [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2002-06-01

    Electromagnetic form factors are fundamental quantities in describing the underlying electromagnetic structure of nucleons. While proton electromagnetic form factors have been determined with good precision, neutron form factors are known poorly, largely due to the lack of free neutron targets. Jefferson Lab Hall A experiment E95-001, a ''precise measurement of the transverse asymmetry AT' from the quasielastic 3He(e, e') process,'' was therefore designed to determine precisely the neutron magnetic form factor, G$n\\atop{M}$ at low momentum transfer values and was successfully completed in Spring 1999. High precision AT'data in the quasi-elastic region at Q2 values of 0.1 to 0.6 (GeV/c)2 were obtained using a high-pressure spin-exchange optically-pumped polarized 3He gas target with an average polarization of 30%, a longitudinally polarized e- beam, and two High Resolution Spectrometers: HRSe and HRSh. HRSe was employed to detect scattered electrons from the quasi-elastic kinematic region, and HRSh was employed as a elastic polarimetry to monitor the product of the beam and target polarizations. The extraction of form factors is usually model-dependent. Significant constraints on theoretical calculations are provided bu additional high precision quasi-elastic asymmetry data at Q2 values of 0.1 and 0.2 (GeV/c)2 in 3He breakup region, where effects of final state interactions (FSI) and meson exchange currents (MEC) are expected to be large [71]. G$n\\atop{M}$ is extracted from a non-relativistic Faddeev calculation which includes both FSI and MEC at Q2 values of 0.1 and 0.2 (GeV/c)2. The uncertainties of G$n\\atop{M}$ at these Q2 values are comparable to those of recent experiments with deuterium targets [58]. At the higher Q2 values from this experiment, G$n\\atop{M}$ is extracted

  10. The pion pole term in electroproduction of off-mass-shell pions

    International Nuclear Information System (INIS)

    McKellar, B.H.; Ellis, R.G.

    1983-01-01

    The dependence of the invariant amplitudes for electroproduction of off-mass-shell pions on the pion Born term is investigated when current algebra Ward identities and PCAC are used to determine pion electroproduction invariant amplitudes. The authors show that an amplitude satisfying the Ward identities can be constructed starting from the usual Born terms which do not satisfy them and that this same amplitude will be obtained for a large class of input Born terms

  11. QCD mixing effects in a gauge invariant quark model for photo- and electroproduction of baryon resonances

    International Nuclear Information System (INIS)

    Zhenping Li; Close, F.E.

    1990-03-01

    The photo and electroproduction of baryon resonances has been calculated using the Constituent Quark Model with chromodynamics consistent with O(υ 2 /c 2 ) for the quarks. We find that the successes of the nonrelativistic quark model are preserved, some problems are removed and that QCD mixing effects may become important with increasing q 2 in electroproduction. For the first time both spectroscopy and transitions receive a unified treatment with a single set of parameters. (author)

  12. Measurement of double polarized asymmetries in quasi-elastic processes ${}^3\\vec{He}(\\vec{e},e' d)$ and ${}^3\\vec{He}(\\vec{e},e' p)$

    Energy Technology Data Exchange (ETDEWEB)

    Mihovilovic, Miha [Univ. of Ljubljana (Slovenia)

    2012-01-01

    This thesis is dedicated to a study of a spin-isospin structure of the polarized 3He. First, an introduction to the spin structure of 3He is given, followed by a brief overview of past experiments. The main focus of the thesis is the E05-102 experiment at Jefferson Lab, in which the reactions ${}^3\\vec{He}(\\vec{e},e' d)$ and ${}^3\\vec{He}(\\vec{e},e' p)$ in the quasi-elastic region were studied. The purpose of this experiment was to better understand the effects of the S'- and D-state contributions to the 3He ground-state wave-functions by a precise measurement of beam-target asymmetries Ax and Az in the range of recoil momenta from 0 to about 300 MeV/c. The experimental equipment utilized in these measurements is described, with special attention devoted to the calibration of the hadron spectrometer, BigBite. Results on the measured asymmetries are presented, together with first attempts at their comparison to the state-of-the art Faddeev calculations. The remaining open problems and challenges for future work are also discussed.

  13. Measurement of the νμ Charged Current π+ to Quasi-Elastic Cross Section Ratio on Mineral Oil in a 0.8 GeV Neutrino Beam

    Energy Technology Data Exchange (ETDEWEB)

    Linden, Steven K. [Yale Univ., New Haven, CT (United States)

    2011-01-01

    Charged current single pion production (CCπ+) and charged current quasi-elastic scattering (CCQE) are the most abundant interaction types for neutrinos at energies around 1 GeV, a region of great interest to oscillation experiments. The cross-sections for these processes, however, are not well understood in this energy range. This dissertation presents a measurement of the ratio of CCπ+ to CCQE cross-sections for muon neutrinos on mineral oil (CH2) in the MiniBooNE experiment. The measurement is presented here both with and without corrections for hadronic re-interactions in the target nucleus and is given as a function of neutrino energy in the range 0.4 GeV < Eν < 2.4 GeV. With more than 46,000 CCπ+ events collected in MiniBooNE, and with a fractional uncertainty of roughly 11% in the region of highest statistics, this measurement represents a dramatic improvement in statistics and precision over previous CCπ+ and CCQE measurements.

  14. Transversity GPD in photo- and electroproduction of two vectormesons

    Energy Technology Data Exchange (ETDEWEB)

    Enberg, Rikard; Pire, Bernard; Szymanowski, Lech

    2006-01-17

    The chiral-odd generalized parton distribution (GPD), or transversity GPD, of the nucleon can be accessed experimentally through the photo- or electroproduction of two vector mesons on a polarized nucleon target, {gamma}{sup (*)}N {yields} {rho}{sub 1}{rho}{sub 2}N', where {rho}{sub 1} is produced at large transverse momentum, {rho}{sub 2} is transversely polarized, and the mesons are separated by a large rapidity gap. We predict the cross section for this process for both transverse and longitudinal {rho}{sub 2} production. To this end we propose a model for the transversity GPDH{sub T}(x,{zeta},t), and give an estimate of the relative sizes of the transverse and longitudinal {rho}{sub 2}cross sections. We show that a dedicated experiment at high energy should be able to measure the transversity content of the proton.

  15. Pomeron-Odderon interference effects in electroproduction of two pions

    CERN Document Server

    Hägler, P; Szymanowski, L; Teryaev, O V

    2002-01-01

    We study Pomeron-Odderon interference effects giving rise to charge and single-spin asymmetries in diffractive electroproduction of a pi sup + pi sup - pair. We calculate these asymmetries, originating from both longitudinal and transverse polarizations of the virtual photon, in the framework of QCD and in the Born approximation, in a kinematical domain accessible to HERA experiments. We predict a sizable charge asymmetry with a characteristic dependence on the invariant mass of the pi sup + pi sup - pair, which makes this observable very important for establishing the magnitude of the Odderon exchange in hard processes. The single-spin asymmetry turns out to be rather small. We briefly discuss future improvements of our calculations and their possible effects on the results. (orig.)

  16. Color transparency in incoherent electroproduction of ρ mesons off nuclei

    International Nuclear Information System (INIS)

    Nemchik, J.; Kopeliovich, B. Z.; Potashnikova, I. K.

    2013-01-01

    Color transparency (CT) phenomena in elastic electroproduction of vector mesons off nuclei are usually infected by the onset of coherence length (CL) effects. However, at low energies corresponding to the CLAS experiment at Jefferson Lab (JLab), one can study practically the net CT effects, since CL is much shorter than the nuclear radius. We investigate various manifestations of CT effects using rigorous quantum mechanical approach based on the path integral technique. We include also the effects of ρ meson decay inside the nucleus leading to a rise of the nuclear suppression towards small values of Q 2 . Motivated by the last CLAS data we predict the A, Q 2 and l c dependence of nuclear transparency for ρ 0 mesons produced incoherently off nuclei. We also perform predictions for expected signal of CT corresponding to the planned JLab upgrade to 12 GeV electron beam.

  17. Measurement of elastic electroproduction of $\\phi$ mesons at HERA

    CERN Document Server

    Adloff, C.; Andrieu, B.; Arkadov, V.; Astvatsatourov, A.; Ayyaz, I.; Babaev, A.; Bahr, J.; Baranov, P.; Barrelet, E.; Bartel, W.; Bassler, U.; Bate, P.; Beglarian, A.; Behnke, O.; Beier, C.; Belousov, A.; Benisch, T.; Berger, Christoph; Bernardi, G.; Berndt, T.; Bizot, J.C.; Borras, K.; Boudry, V.; Braunschweig, W.; Brisson, V.; Broker, H.B.; Brown, D.P.; Bruckner, W.; Bruel, P.; Bruncko, D.; Burger, J.; Busser, F.W.; Bunyatyan, A.; Burkhardt, H.; Burrage, A.; Buschhorn, G.; Campbell, A.J.; Cao, Jun; Carli, T.; Caron, S.; Chabert, E.; Clarke, D.; Clerbaux, B.; Collard, C.; Contreras, J.G.; Coughlan, J.A.; Cousinou, M.C.; Cox, B.E.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Dau, W.D.; Daum, K.; David, M.; Davidsson, M.; Delcourt, B.; Delerue, N.; Demirchyan, R.; De Roeck, A.; De Wolf, E.A.; Diaconu, C.; Dixon, P.; Dodonov, V.; Dowell, J.D.; Droutskoi, A.; Duprel, C.; Eckerlin, Guenter; Eckstein, D.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eisenhandler, E.; Ellerbrock, M.; Elsen, E.; Erdmann, M.; Erdmann, W.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Ferencei, J.; Ferron, S.; Fleischer, M.; Flugge, G.; Fomenko, A.; Foresti, I.; Formanek, J.; Foster, J.M.; Franke, G.; Gabathuler, E.; Gabathuler, K.; Garvey, J.; Gassner, J.; Gayler, Joerg; Gerhards, R.; Ghazarian, S.; Goerlich, L.; Gogitidze, N.; Goldberg, M.; Goodwin, C.; Grab, C.; Grassler, H.; Greenshaw, T.; Grindhammer, Guenter; Hadig, T.; Haidt, D.; Hajduk, L.; Haynes, W.J.; Heinemann, B.; Heinzelmann, G.; Henderson, R.C.W.; Hengstmann, S.; Henschel, H.; Heremans, R.; Herrera, G.; Herynek, I.; Hilgers, M.; Hiller, K.H.; Hladky, J.; Hoting, P.; Hoffmann, D.; Hoprich, W.; Horisberger, R.; Hurling, S.; Ibbotson, M.; Issever, C.; Jacquet, M.; Jaffre, M.; Janauschek, L.; Jansen, D.M.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, D.P.; Jones, M.A.S.; Jung, H.; Kastli, H.K.; Kant, D.; Kapichine, M.; Karlsson, M.; Karschnick, O.; Kaufmann, O.; Kausch, M.; Keil, F.; Keller, N.; Kennedy, J.; Kenyon, I.R.; Kermiche, S.; Kiesling, Christian M.; Klein, M.; Kleinwort, C.; Knies, G.; Koblitz, B.; Kolya, S.D.; Korbel, V.; Kostka, P.; Kotelnikov, S.K.; Krasny, M.W.; Krehbiel, H.; Kroseberg, J.; Krucker, D.; Kruger, K.; Kupper, A.; Kuhr, T.; Kurca, T.; Kutuev, R.; Lachnit, W.; Lahmann, R.; Lamb, D.; Landon, M.P.J.; Lange, W.; Lastovicka, T.; Lebedev, A.; Leissner, B.; Lemrani, R.; Lendermann, V.; Levonian, S.; Lindstrom, M.; Lobodzinska, E.; Lobodzinski, B.; Loktionova, N.; Lubimov, V.; Luders, S.; Luke, D.; Lytkin, L.; Magnussen, N.; Mahlke-Kruger, H.; Malden, N.; Malinovski, E.; Malinovski, I.; Maracek, R.; Marage, P.; Marks, J.; Marshall, R.; Martyn, H.U.; Martyniak, J.; Maxfield, S.J.; Mehta, A.; Meier, K.; Merkel, P.; Metlica, F.; Meyer, H.; Meyer, J.; Meyer, P.O.; Mikocki, S.; Milstead, D.; Mkrtchyan, T.; Mohr, R.; Mohrdieck, S.; Mondragon, M.N.; Moreau, F.; Morozov, A.; Morris, J.V.; Muller, K.; Murin, P.; Nagovizin, V.; Naroska, B.; Naumann, J.; Naumann, T.; Nellen, G.; Newman, Paul R.; Nicholls, T.C.; Niebergall, F.; Niebuhr, C.; Nix, O.; Nowak, G.; Nunnemann, T.; Olsson, J.E.; Ozerov, D.; Panassik, V.; Pascaud, C.; Patel, G.D.; Perez, E.; Phillips, J.P.; Pitzl, D.; Poschl, R.; Potachnikova, I.; Povh, B.; Rabbertz, K.; Radel, G.; Rauschenberger, J.; Reimer, P.; Reisert, B.; Reyna, D.; Riess, S.; Rizvi, E.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Royon, C.; Rusakov, S.; Rybicki, K.; Sankey, D.P.C.; Scheins, J.; Schilling, F.P.; Schleper, P.; Schmidt, D.; Schoeffel, L.; Schoning, A.; Schorner, T.; Schroder, V.; Schultz-Coulon, H.C.; Sedlak, K.; Sefkow, F.; Chekelian, V.I.; Sheviakov, I.; Shtarkov, L.N.; Siegmon, G.; Sievers, P.; Sirois, Y.; Sloan, T.; Smirnov, P.; Solochenko, V.; Solovev, Y.; Spaskov, V.; Specka, Arnd E.; Spitzer, H.; Stamen, R.; Steinhart, J.; Stella, B.; Stellberger, A.; Stiewe, J.; Straumann, U.; Struczinski, W.; Swart, M.; Tasevsky, M.; Tchernyshov, V.; Tchetchelnitski, S.; Thompson, Graham; Thompson, P.D.; Tobien, N.; Traynor, D.; Truoel, Peter; Tsipolitis, G.; Turnau, J.; Turney, J.E.; Tzamariudaki, E.; Udluft, S.; Usik, A.; Valkar, S.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vazdik, Y.; von Dombrowski, S.; Wacker, K.; Wallny, R.; Walter, T.; Waugh, B.; Weber, G.; Weber, M.; Wegener, D.; Wegner, A.; Wengler, T.; Werner, M.; White, G.; Wiesand, S.; Wilksen, T.; Winde, M.; Winter, G.G.; Wissing, C.; Wobisch, M.; Wollatz, H.; Wunsch, E.; Wyatt, A.C.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhokin, A.; Zomer, F.; Zsembery, J.

    2000-01-01

    The elastic electroproduction of phi mesons is studied at HERA with the H1 detector for photon virtualities 1 < Q^2 < 15 GeV^2 and hadronic centre of mass energies 40 < W < 130 GeV. The Q^2 and t dependences of the cross section are extracted (t being the square of the four-momentum transfer to the target proton). When plotted as function of (Q^2 + M_V^2) and scaled by the appropriate SU(5) quark charge factor, the phi meson cross section agrees within errors with the cross sections of the vector mesons V = rho, omega and J/psi. A detailed analysis is performed of the phi meson polarisation state and the ratio of the production cross sections for longitudinally and transversely polarised phi mesons is determined. A small but significant violation of s-channel helicity conservation (SCHC) is observed.

  18. High-energy photoproduction and electroproduction of π+ on nuclei

    International Nuclear Information System (INIS)

    Kuz'menko, V.S.; Mitrofanova, A.V.; Noga, V.I.; Ranyuk, Y.N.; Sorokin, P.V.; Telegin, Y.N.; Blomqvist, I.; Jonsson, G.G.; Freed, N.

    1977-01-01

    Cross sections for photoproduction and electroproduction of π + on 27 Al and 51 V leading to bound states in the daughter nuclei have been measured at Kharkov in the energy range 600--1200 MeV by use of the activation method. Careful comparison is made to other recent results obtained at intermediate and high energies. Agreement is found between the present data and results of earlier work carried out at Lund and DESY. Discrepancies between photoproduction data taken at different laboratories are attributed to differences between methods of background subtraction. Relative bremsstrahlung-induced to electron-induced yield ratios are compared with predictions based on the Dalitz-Yennie formalism for virtual-photon spectra

  19. Pion Electroproduction form Helium 3, Deuterium, and Hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Avery, Stephen Milton [Hampton Univ., Hampton, VA (United States)

    2002-05-01

    A series of measurements for pion electroproduction from helium-3, deuterium, and hydrogen were completed at the Thomas Jefferson National Accelerator Facility by the NucPi Collaboration. E91003 began taking data in February 1998 and was completed in April 1998. The longitudinal and transverse parts of the differential cross section were extracted, by means of a Rosenbluth type separation, in the direction parallel to the virtual photon, at Q 2 = 0.4 GeV 2 , for W = 1.15 and W = 1.6 GeV. The mass dependence of the longitudinal cross section should provide insight into the surprising apparent absence of any significant cross section enhancement due to excess pions in the nuclear medium.

  20. Color transparency in incoherent electroproduction of {rho} mesons off nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Nemchik, J. [Institute of Experimental Physics SAS, Watsonova 47, 04001 Kosice, Slovakia and Czech Technical University, FNSPE, Brehova 7, 11519 Praque (Czech Republic); Kopeliovich, B. Z.; Potashnikova, I. K. [Departamento de Fisica y Centro de Estudios Subatomicos, Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile)

    2013-04-15

    Color transparency (CT) phenomena in elastic electroproduction of vector mesons off nuclei are usually infected by the onset of coherence length (CL) effects. However, at low energies corresponding to the CLAS experiment at Jefferson Lab (JLab), one can study practically the net CT effects, since CL is much shorter than the nuclear radius. We investigate various manifestations of CT effects using rigorous quantum mechanical approach based on the path integral technique. We include also the effects of {rho} meson decay inside the nucleus leading to a rise of the nuclear suppression towards small values of Q{sup 2}. Motivated by the last CLAS data we predict the A, Q{sup 2} and l{sub c} dependence of nuclear transparency for {rho}{sup 0} mesons produced incoherently off nuclei. We also perform predictions for expected signal of CT corresponding to the planned JLab upgrade to 12 GeV electron beam.

  1. A chiral quark model for meson electroproduction in the S11 partial wave

    International Nuclear Information System (INIS)

    Golli, B.; Sirca, S.

    2011-01-01

    We calculate the meson scattering and electroproduction amplitudes in the S11 partial wave in a coupled-channel approach that incorporates quasi-bound quark-model states. Using the quark wave functions and the quark-meson interaction from the Cloudy Bag Model, we obtain a good overall agreement with the available experimental results for the partial widths of the N(1535) and the N(1650) resonances as well as for the pion, eta and kaon electroproduction amplitudes. Our model is consistent with the N(1535) resonance being dominantly a genuine three-quark state rather than a quasi-bound state of mesons and baryons. (orig.)

  2. Quasifree pion electroproduction from nuclei in the {Delta} region

    Energy Technology Data Exchange (ETDEWEB)

    Lee, F X [TRIUMF, Vancouver, BC (Canada); Wright, L E [Ohio Univ., Inst. of Nuclear and Particle Physics, Dept. of Physics, Athens, OH (United States); Bennhold, C [George Washington Univ., Center for Nuclear Studies, Dept. of Physics, Washington, DC (United States)

    1995-10-01

    We present calculations of the reaction {Alpha} (e, e{sup 1}{pi} N)B in the distorted wave impulse approximation. The reaction allows for the study of the production process in the nuclear medium without being obscured by the details of nuclear transition densities. First, a pion electroproduction operator suitable for nuclear calculations is obtained by extending the Blomqvist-Laget photoproduction operator to the virtual photon case. The operator is gauge invariant, unitary, reference frame independent, and describes the existing data reasonably well. Then it is applied in nuclei to predict nuclear cross sections under a variety of kinematic arrangements. Issues such as the effects of gauge-fixing, the interference of the {Delta} resonance with the background, sensitivities to be guadrupole component of the {Delta} excitation and to the electromagnetic form factors, the role of final-state interactions, are studied in detail. Methods on how to experimentally separate the various pieces in the coincidence cross section are suggested. Finally, the model is compared to recent SLAC experiment. (authors) 35 refs., 22 figs.

  3. Quasifree pion electroproduction from nuclei in the Δ region

    International Nuclear Information System (INIS)

    Lee, F.X.; Wright, L.E.; Bennhold, C.

    1995-10-01

    We present calculations of the reaction Α (e, e 1 π N)B in the distorted wave impulse approximation. The reaction allows for the study of the production process in the nuclear medium without being obscured by the details of nuclear transition densities. First, a pion electroproduction operator suitable for nuclear calculations is obtained by extending the Blomqvist-Laget photoproduction operator to the virtual photon case. The operator is gauge invariant, unitary, reference frame independent, and describes the existing data reasonably well. Then it is applied in nuclei to predict nuclear cross sections under a variety of kinematic arrangements. Issues such as the effects of gauge-fixing, the interference of the Δ resonance with the background, sensitivities to be guadrupole component of the Δ excitation and to the electromagnetic form factors, the role of final-state interactions, are studied in detail. Methods on how to experimentally separate the various pieces in the coincidence cross section are suggested. Finally, the model is compared to recent SLAC experiment. (authors)

  4. Neutral pion electroproduction off light nuclei in chiral perturbation theory

    International Nuclear Information System (INIS)

    Lenkewitz, Mark

    2013-01-01

    Threshold pion electroproduction on tri-nucleon systems is investigated in the framework of baryon Chiral Perturbation Theory (ChPT) at next-to-leading one-loop order O(q 4 ) in the chiral expansion. To this order in small momenta, the production operator is a sum of one- and two-nucleon terms. While the one-nucleon terms resemble the impulse approximation, the two-nucleon contributions represent corrections due to the relevant nuclear interactions, e.g. pion-exchange interactions, which prove to be dominant, and due to recoil effects of the participating nucleons, which appear to be negligible. We calculate the expectation value of the production operator using chiral wave functions in a three-dimensional approach without partial wave expansion. The resulting integrals are evaluated using adaptive Monte Carlo integration, the VEGAS algorithm of Lepage. We obtain results for the threshold production multipoles E 0+ and L 0+ on 3 He and 3 H and comment on the sensitivity to the fundamental neutron amplitude E 0+ π 0 n . 3 He appears to be a particularly promising target to extract information about the neutron amplitude. This idea is usually invoked for spin-dependent quantities since the 3 He wave function is strongly dominated by the principal S-state component which suggests that its spin is largely driven by the one of the neutron.

  5. Deeply virtual and exclusive electroproduction of omega mesons

    International Nuclear Information System (INIS)

    Morand, L.

    2005-01-01

    The exclusive omega electroproduction off the proton was studied in a large kinematical domain above the nucleon resonance region and for the highest possible photon virtuality (Q 2 ) with the 5.75 GeV beam at CEBAF and the CLAS spectrometer. Cross sections were measured up to large values of the four-momentum transfer (-t 2 ) to the proton. The contributions of the interference terms sigma TT and sigma TL to the cross sections, as well as an analysis of the omega spin density matrix, indicate that helicity is not conserved in this process. The t-channel pi 0 exchange, or more generally the exchange of the associated Regge trajectory, seems to dominate the reaction γ* p → omega p, even for Q 2 as large as 5 GeV 2 . Contributions of handbag diagrams, related to Generalized Parton Distributions in the nucleon, are therefore difficult to extract for this process. Remarkably, the high-t behavior of the cross sections is nearly Q 2 -independent, which may be interpreted as a coupling of the photon to a point-like object in this kinematical limit

  6. Color transparency in semi-inclusive electroproduction of ρ mesons

    International Nuclear Information System (INIS)

    Frankfurt, L.; Miller, G. A.; Strikman, M.

    2008-01-01

    We study the electroproduction of ρ mesons in nuclei at intermediate energies, deriving a treatment of the energy lost by the ρ in each step of multiple scattering. This enables a close match between calculations and the experimental kinematic conditions. A standard Glauber calculation is presented, and then the effects of color-transparency are included. The influence of poor experimental resolution on the extracted transparency is assessed. The effects of ρ meson decay inside the nucleus are examined, and are typically about 5% at most. This effect disappears rapidly as Q 2 increases from about 1 to 3 GeV 2 , causing a rise in the transparency that is not attributable to color transparency. The size of color transparency effects for C and Fe nuclei is studied for values of Q 2 up to 10 GeV 2 . The detailed results depend strongly on the assumed value of the ρN cross section. The overall effects of color transparency are greater than about 10% for both nuclear targets if Q 2 is greater than about 5 GeV 2

  7. Electroproduction of the Delta(1232) Resonance at High Momentum Transfer

    International Nuclear Information System (INIS)

    Valera Frolov; Gary Adams; Abdellah Ahmidouch; Christopher Armstrong; Ketevi Assamagan; Steven Avery; Baker, O.; Peter Bosted; Volker Burkert; Roger Carlini; Davidson, R.M.; James Dunne; Eden, T.; Rolf Ent; David Gaskell; Paul Gueye; Wendy Hinton; Cynthia Keppel; Wooyoung Kim; Mike Klusman; Douglas Koltenuk; David Mack; Richard Madey; David Meekins; Ralph Minehart; Joseph Mitchell; Hamlet Mkrtchyan; Mukhopadhyay, N.C.A.; James Napolitano; Gabriel Niculescu; Maria-Ioana Niculescu; Mina Nozar; John Price; Paul Stoler; Vardan Tadevosyan; Liguang Tang; Michael Witkowski; Stephen Wood

    1999-01-01

    Jefferson Lab experiment E94-014 measured the excitation of the Delta (1232) resonance via the reaction p(e,e(prime)p)π 0 at Q 2 near 2.8 and 4 Gev 2 . This is the highest Q 2 for which exclusive resonance electroproduction has ever been observed. Decay distributions of the Delta (1232) resonance into the ppi 0 final state were measured over a wide range of barycentric decay angles and energies. The goal of this experiment is to assess the transition in Q 2 from the constituent quark model (CQM) to the regime where hard processes become important. At Q 2 ∼ few GeV 2 /c 2 the ratio E 1+ /M 1+ depends dramatically on the theoretical description, varying from a few 10 -2 in the CQM limit, to about 1 in the pQCD limit. Preliminary analysis of the data shows that the ratio E 1+ /M 1+ remains small at Q 2 up to 4 Gev 2 /c 2 . After first pass analysis we obtain E 1+ /M 1+ = -4.1 ± 1.2 at Q 2 = 2.8 Gev 2 /c 2 and E 1+ /M 1+ = -7.9 ± 0.8 at Q 2 = 4 Gev 2 /c 2 (statistical errors only)

  8. Diffractive Electroproduction of rho and phi Mesons at HERA

    CERN Document Server

    Aaron, F.D.; Alexa, C.; Andreev, V.; Antunovic, B.; Asmone, A.; Backovic, S.; Baghdasaryan, A.; Barrelet, E.; Bartel, W.; Begzsuren, K.; Belousov, A.; Bizot, J.C.; Boudry, V.; Bozovic-Jelisavcic, I.; Bracinik, J.; Brandt, G.; Brinkmann, M.; Brisson, V.; Bruncko, D.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Cantun Avila, K.B.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Cholewa, A.; Contreras, J.G.; Coughlan, J.A.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Daum, K.; Deak, M.; de Boer, Y.; Delcourt, B.; Del Degan, M.; Delvax, J.; De Wolf, E.A.; Diaconu, C.; Dodonov, V.; Dossanov, A.; Dubak, A.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eliseev, A.; Elsen, E.; Falkiewicz, A.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Fischer, D.J.; Fleischer, M.; Fomenko, A.; Gabathuler, E.; Gayler, J.; Ghazaryan, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Gogitidze, N.; Gouzevitch, M.; Grab, C.; Greenshaw, T.; Grell, B.R.; Grindhammer, G.; Habib, S.; Haidt, D.; Helebrant, C.; Henderson, R.C.W.; Hennekemper, E.; Henschel, H.; Herbst, M.; Herrera, G.; Hildebrandt, M.; Hiller, K.H.; Hoffmann, D.; Horisberger, R.; Hreus, T.; Jacquet, M.; Janssen, M.E.; Janssen, X.; Jonsson, L.; Jung, A.W.; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I.R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Kluge, T.; Knutsson, A.; Kogler, R.; Kostka, P.; Kraemer, M.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Kruger, K.; Kutak, K.; Landon, M.P.J.; Lange, W.; Lastovicka-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Li, G.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lytkin, L.; Makankine, A.; Malinovski, E.; Marage, P.; Marti, Ll.; Martyn, H.U.; Maxfield, S.J.; Mehta, A.; Meyer, A.B.; Meyer, H.; Meyer, H.; Meyer, J.; Michels, V.; Mikocki, S.; Milcewicz-Mika, I.; Moreau, F.; Morozov, A.; Morris, J.V.; Mozer, M.U.; Mudrinic, M.; Muller, K.; Murin, P.; Naumann, Th.; Newman, P.R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Olivier, B.; Olsson, J.E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Pandurovic, M.; Papadopoulou, Th.; Pascaud, C.; Patel, G.D.; Pejchal, O.; Perez, E.; Petrukhin, A.; Picuric, I.; Piec, S.; Pitzl, D.; Placakyte, R.; Pokorny, B.; Polifka, R.; Povh, B.; Preda, T.; Radescu, V.; Rahmat, A.J.; Raicevic, N.; Raspiareza, A.; Ravdandorj, T.; Reimer, P.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rotaru, M.; Ruiz Tabasco, J.E.; Rurikova, Z.; Rusakov, S.; Salek, D.; Sankey, D.P.C.; Sauter, M.; Sauvan, E.; Schmitt, S.; Schoeffel, L.; Schoning, A.; Schultz-Coulon, H.C.; Sefkow, F.; Shaw-West, R.N.; Shtarkov, L.N.; Shushkevich, S.; Sloan, T.; Smiljanic, I.; Soloviev, Y.; Sopicki, P.; South, D.; Spaskov, V.; Specka, A.; Staykova, Z.; Steder, M.; Stella, B.; Stoicea, G.; Straumann, U.; Sunar, D.; Sykora, T.; Tchoulakov, V.; Thompson, G.; Thompson, P.D.; Toll, T.; Tomasz, F.; Tran, T.H.; Traynor, D.; Trinh, T.N.; Truol, P.; Tsakov, I.; Tseepeldorj, B.; Turnau, J.; Urban, K.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Vinokurova, S.; Volchinski, V.; von den Driesch, M.; Wegener, D.; Wissing, Ch.; Wunsch, E.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhokin, A.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.; Zus, R.

    2010-01-01

    Diffractive electroproduction of rho and phi mesons is measured at HERA with the H1 detector in the elastic and proton dissociative channels. The data correspond to an integrated luminosity of 51 pb^-1. About 10500 rho and 2000 phi events are analysed in the kinematic range of squared photon virtuality 2.5 < Q^2 < 60 GeV^2, photon-proton centre of mass energy 35 < W < 180 GeV and squared four-momentum transfer to the proton |t| < 3 GeV^2. The total, longitudinal and transverse cross sections are measured as a function of Q^2, W and |t|. The measurements show a transition to a dominantly "hard" behaviour, typical of high gluon densities and small q\\bar{q} dipoles, for Q^2 larger than 10 to 20 GeV^2. They support flavour independence of the diffractive exchange, expressed in terms of the scaling variable (Q^2 + M_V^2)/4, and proton vertex factorisation. The spin density matrix elements are measured as a function of kinematic variables. The ratio of the longitudinal to transverse cross sections, t...

  9. Deeply virtual and exclusive electroproduction of omega mesons

    Energy Technology Data Exchange (ETDEWEB)

    Morand, L; Et. Al.

    2005-04-01

    The exclusive omega electroproduction off the proton was studied in a large kinematical domain above the nucleon resonance region and for the highest possible photon virtuality (Q{sup 2}) with the 5.75 GeV beam at CEBAF and the CLAS spectrometer. Cross sections were measured up to large values of the four-momentum transfer (-t < 2.7 GeV{sup 2}) to the proton. The contributions of the interference terms sigma{sub TT} and sigma{sub TL} to the cross sections, as well as an analysis of the omega spin density matrix, indicate that helicity is not conserved in this process. The t-channel pi{sup 0} exchange, or more generally the exchange of the associated Regge trajectory, seems to dominate the reaction {gamma}* p {yields} omega p, even for Q{sup 2} as large as 5 GeV{sub 2}. Contributions of handbag diagrams, related to Generalized Parton Distributions in the nucleon, are therefore difficult to extract for this process. Remarkably, the high-t behavior of the cross sections is nearly Q{sup 2}-independent, which may be interpreted as a coupling of the photon to a point-like object in this kinematical limit.

  10. Electroproduction of the neutral pion off 4He

    Energy Technology Data Exchange (ETDEWEB)

    Torayev, Bayram [Old Dominion Univ., Norfolk, VA (United States)

    2016-12-01

    Deeply virtual exclusive processes offer a unique opportunity to study the internal structure of the nucleon and nuclei. The goal of this work is to extract the beam-spin asymmetry in deeply virtual coherent neutral pion electroproduction, e^4He to e'^4He'pi^0, using the CLAS detector in the experimental Hall B at Thomas Jefferson National Accelerator Facility. The data were collected in 2009 with a 6 GeV longitudinally polarized electron beam impinging on a 30 cm long, 6 atm Helium-4 gaseous target. In order to ensure that the process is coherent, a new Radial Time Projection Chamber was used to detect and identify low energy recoil a-particles. The Beam Spin Asymmetry in the coherent deep exclusive regime was measured at Q^2 = 1.50 GeV^2, xB = 0.18 and -t = 0.14 GeV^2. The measured asymmetry has an amplitude of 10%+/-5% and has the opposite sign compared the asymmetry measured for pi^0 production on the proton.

  11. Induced polarization of Λ (1116) in kaon electroproduction

    Science.gov (United States)

    Gabrielyan, M.; Raue, B. A.; Carman, D. S.; Park, K.; Adhikari, K. P.; Adikaram, D.; Amaryan, M. J.; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Baturin, V.; Bedlinskiy, I.; Biselli, A. S.; Bono, J.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Cao, T.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Doughty, D.; Dupre, R.; El Fassi, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fleming, J. A.; Forest, T. A.; Garillon, B.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hattawy, M.; Hicks, K.; Ho, D.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Keller, D.; Khandaker, M.; Kim, W.; Klein, F. J.; Koirala, S.; Kubarovsky, V.; Kuhn, S. E.; Kuleshov, S. V.; Lenisa, P.; Levine, W. I.; Livingston, K.; MacGregor, I. J. D.; Mayer, M.; McKinnon, B.; Meyer, C. A.; Mestayer, M. D.; Mirazita, M.; Mokeev, V.; Moody, C. I.; Moutarde, H.; Movsisyan, A.; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Osipenko, M.; Pappalardo, L. L.; Paremuzyan, R.; Pasyuk, E.; Peng, P.; Phelps, W.; Phillips, J. J.; Pisano, S.; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Protopopescu, D.; Rimal, D.; Ripani, M.; Rizzo, A.; Sabatié, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Simonyan, A.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Stepanyan, S. S.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Tang, W.; Ungaro, M.; Vlassov, A. V.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Zachariou, N.; Zana, L.; Zhang, J.; Zonta, I.; CLAS Collaboration

    2014-09-01

    We have measured. the induced polarization of the Λ(1116) in the reaction ep →e'K+Λ, detecting the scattered e' and K+ in the final state along with the proton from the decay Λ →pπ-. The present study used the CEBAF Large Acceptance Spectrometer (CLAS), which allowed for a large kinematic acceptance in invariant energy W (1.6≤W≤2.7 GeV) and covered the full range of the kaon production angle at an average momentum transfer Q2=1.90GeV2. In this experiment a 5.50-GeV electron beam was incident upon an unpolarized liquid-hydrogen target. We have mapped out the W and kaon production angle dependencies of the induced polarization and found striking differences from photoproduction data over most of the kinematic range studied. However, we also found that the induced polarization is essentially Q2 independent in our kinematic domain, suggesting that somewhere below the Q2 covered here there must be a strong Q2 dependence. Along with previously published photo- and electroproduction cross sections and polarization observables, these data are needed for the development of models, such as effective field theories, and as input to coupled-channel analyses that can provide evidence of previously unobserved s-channel resonances.

  12. Deep exclusive π+ electroproduction off the proton at CLAS

    Science.gov (United States)

    Park, K.; Guidal, M.; Gothe, R. W.; Laget, J. M.; Garçon, M.; Adhikari, K. P.; Aghasyan, M.; Amaryan, M. J.; Anghinolfi, M.; Avakian, H.; Baghdasaryan, H.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Bedlinsky, I.; Bennett, R. P.; Biselli, A. S.; Bookwalter, C.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Daniel, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dodge, G. E.; Doughty, D.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fleming, J. A.; Forest, T. A.; Fradi, A.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gohn, W.; Golovatch, E.; Graham, L.; Griffioen, K. A.; Guegan, B.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Heddle, D.; Hicks, K.; Ho, D.; Holtrop, M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Jenkins, D.; Jo, H. S.; Keller, D.; Khandaker, M.; Khetarpal, P.; Kim, A.; Kim, W.; Klein, F. J.; Koirala, S.; Kubarovsky, A.; Kubarovsky, V.; Kuhn, S. E.; Kuleshov, S. V.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Mao, Y.; Markov, N.; Martinez, D.; Mayer, M.; McKinnon, B.; Meyer, C. A.; Mineeva, T.; Mirazita, M.; Mokeev, V.; Moutarde, H.; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Nepali, C. S.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Pappalardo, L. L.; Paremuzyan, R.; Park, S.; Pasyuk, E.; Anefalos Pereira, S.; Phelps, E.; Pisano, S.; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Ricco, G.; Rimal, D.; Ripani, M.; Rosner, G.; Rossi, P.; Sabatié, F.; Saini, M. S.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Seraydaryan, H.; Sharabian, Y. G.; Smith, E. S.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Stepanyan, S. S.; Stoler, P.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Tang, W.; Taylor, C. E.; Tian, Ye; Tkachenko, S.; Trivedi, A.; Ungaro, M.; Vernarsky, B.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Weinstein, L. B.; Weygand, D. P.; Wood, M. H.; Zachariou, N.; Zhang, J.; Zhao, Z. W.; Zonta, I.

    2013-01-01

    The exclusive electroproduction of π + above the resonance region was studied using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Laboratory by scattering a 6GeV continuous electron beam off a hydrogen target. The large acceptance and good resolution of CLAS, together with the high luminosity, allowed us to measure the cross section for the γ * p → nπ + process in 140 ( Q 2, x B , t) bins: 0.16 < x B < 0.58, 1.6 GeV2 < Q 2 < 4.5 GeV2 and 0.1 GeV2 < - t < 5.3 GeV2. For most bins, the statistical accuracy is on the order of a few percent. Differential cross sections are compared to four theoretical models, based either on hadronic or on partonic degrees of freedom. The four models can describe the gross features of the data reasonably well, but differ strongly in their ingredients. In particular, the model based on Generalized Parton Distributions (GPDs) contain the interesting potential to experimentally access transversity GPDs.

  13. Transverse target-spin asymmetry in exclusive electroproduction of ρ0 mesons

    International Nuclear Information System (INIS)

    Dreschler, Jeroen

    2008-10-01

    This thesis reports the first measurements of the asymmetry in exclusive ρ 0 electroproduction from a transversely polarized proton. The asymmetry was extracted from data taken by the HERMES experiment at DESY with a polarized internal hydrogen gas target and the 27.6 GeV electron (positron) beam of HERA. (orig.)

  14. Transverse target-spin asymmetry in exclusive electroproduction of {rho}{sup 0} mesons

    Energy Technology Data Exchange (ETDEWEB)

    Dreschler, Jeroen

    2008-10-15

    This thesis reports the first measurements of the asymmetry in exclusive {rho}{sup 0} electroproduction from a transversely polarized proton. The asymmetry was extracted from data taken by the HERMES experiment at DESY with a polarized internal hydrogen gas target and the 27.6 GeV electron (positron) beam of HERA. (orig.)

  15. Final states in electroproduction and photoproduction at low and medium energies

    International Nuclear Information System (INIS)

    Marshall, R.

    1977-01-01

    A review is given of electroproduction and photoproduction at photon energies extending from the resonance region up to about 10 GeV. Comparisons are made between the various experiments and the appropriate theories in an attempt to understand more about the different production mechanisms - s channel resonances, t and u channel exchanges and quark-parton effects. (orig.) [de

  16. Electroproduction of associated two-body final states

    International Nuclear Information System (INIS)

    Harding, D.J.

    1983-01-01

    The Large Aperture Magnet Experiment at the Cornell Electron Synchrotron measured electron scattering in the region 2.98 2 and 0.5 2 2 . The 11.5 GeV extracted electron beam struck a liquid hydrogen target in an eight kilogauss magnetic field. The charged particles in the final state were tracked through the field by a multiwire proportional chamber system of 34 planes. A lead-scintillator shower counter triggered the experiment on detection of a scattered electron. Time-of-flight and water Cherenkov counters identified some of the final state hadrons. The data recorded on tape was then passed through computer programs which linked proportional chamber strikes into tracks, fit momenta to the tracks, applied particle identification algorithms, selected interesting events, and plotted histograms of invariant masses. All of this is described here in detail, with special attention to the front-end electronics and the track-finding program. Many specific final states were observed. The analysis presented here concentrates on the reaction γ/sub v/p→pπ + ππ 0 , with the final hadrons resulting from the decay of a two-body state. The states pω 0 and p eta 0 are measured. Limits are set for the production of Δ + + rho - , Δ + rho 0 , and Δp + . The conclusion the author draws is that hadron-like two-body processes are almost completely absent in virtual photon scattering in this kinematic region. Vector meson production, excitation of the nucleons, and the scattering of the photons directly from individual partons are the important processes

  17. Diffractive electroproduction of {rho} and {phi} mesons at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Aaron, F.D. [National Inst. for Physics and Nuclear Engineering (NIPNE), Bucharest (Romania); Bucharest Univ. (Romania). Faculty of Physics; Aldaya Martin, M. [DESY Hamburg (Germany); Alexa, C. [National Inst. for Physics and Nuclear Engineering (NIPNE), Bucharest (RO)] (and others)

    2009-06-15

    Diffractive electroproduction of {rho} and {phi} mesons is measured at HERA with the H1 detector in the elastic and proton dissociative channels. The data correspond to an integrated luminosity of 51 pb{sup -1}. About 10500 {rho} and 2000 {phi} events are analysed in the kinematic range of squared photon virtuality 2.5{<=}Q{sup 2}{<=}60 GeV{sup 2}, photon-proton centre of mass energy 35{<=}W{<=}180 GeV and squared four-momentum transfer to the proton vertical stroke 3 vertical stroke {<=} GeV{sup 2}. The total, longitudinal and transverse cross sections are measured as a function of Q{sup 2}, W and vertical stroke 3 vertical stroke. The measurements show a transition to a dominantly ''hard'' behaviour, typical of high gluon densities and small q anti q dipoles, for Q{sup 2} larger than 10 to 20 GeV{sup 2}. They support flavour independence of the diffractive exchange, expressed in terms of the scaling variable (Q{sup 2}+M{sub V}{sup 2})/4, and proton vertex factorisation. The spin density matrix elements are measured as a function of kinematic variables. The ratio of the longitudinal to transverse cross sections, the ratio of the helicity amplitudes and their relative phases are extracted. Several of these measurements have not been performed before and bring new information on the dynamics of diffraction in a QCD framework. The measurements are discussed in the context of models using generalised parton distributions or universal dipole cross sections. (orig.)

  18. Dynamics of water and ions in clays of type montmorillonite by microscopic simulation and quasi-elastic neutron scattering; Dynamique de l'eau et des ions dans des argiles de type montmorillonite par simulation microscopique et diffusion quasi-elastique des neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Malikova, N

    2005-09-15

    Montmorillonite clays in low hydration states, with Na{sup +} and Cs{sup +} compensating counter ions, are investigated by a combination of microscopic simulation and quasi-elastic neutron scattering to obtain information on the local structure and dynamics of water and ions in the interlayer. At first predictions of simulation into the dynamics of water and ions at elevate temperatures are shown (0 deg C 80 deg C, pertinent for the radioactive waste disposal scenario) Marked difference is observed between the modes of diffusion of the Na{sup +} and C{sup +} counter ions. In water dynamics, a significant step towards bulk water behaviour is seen on transition from the mono- to bilayer states. Secondly, a detailed comparison between simulation and quasi-elastic neutron scattering (Neutron Spin Echo and Time-of-Flight) regarding ambient temperature water dynamics is presented. Overall, the approaches are found to be in good agreement with each other and limitations of each of the methods are clearly shown. (author)

  19. What can we learn from unpolarized and polarized electroproduction of fast baryons

    International Nuclear Information System (INIS)

    Artru, X.

    1991-01-01

    Two applications of semi-inclusive electroproduction of fast baryons are presented: (i) The steepness of the baryon spectrum at medium rapidity can give information about the general mechanisms of baryon production in soft and hard processes. (ii) With a polarized target and a detector which analyses the polarization of final Λ's, the aptitude of quarks to carry transverse polarization can be tested for the first time

  20. What can we learn from unpolarized and polarized electroproduction of fast baryons?

    International Nuclear Information System (INIS)

    Artru, X.; Mekhfi, M.

    1991-01-01

    Two applications of semi-inclusive electroproduction of fast baryons are presented: (i) The steepness of the baryon spectrum at medium rapidity can give information about the general mechanisms of baryon production in soft and hard processes. (ii) With a polarized target and a detector which analyses the polarization of final Λ's, the aptitude of quarks to carry transverse polarization can be tested for the first time. (orig.)

  1. Search for low mass exotic baryons in one pion electroproduction data measured at JLAB

    International Nuclear Information System (INIS)

    Tatischeff, B.; Tomasi-Gustafsson, E.

    2007-02-01

    This paper aims to give further evidence for the existence of low mass exotic baryons. Narrow structures in baryonic missing mass or baryonic invariant mass were previously observed during the last ten years. Since their existence is sometimes questionable, the structure functions of one pion electroproduction cross sections, measured at JLAB, are studied to add information on the possible existence of these narrow exotic baryonic resonances. (authors)

  2. Electroproduction cross section of large-E bot hadrons at NLO and virtual photon structure function

    International Nuclear Information System (INIS)

    Fontannaz, M.

    2004-01-01

    We calculate higher order corrections to the resolved component of the electroproduction cross section of large- E bot hadrons. The parton distributions in the virtual photon are studied in detail and a NLO parametrization of the latter is proposed. The contribution of the resolved component to the forward production of large- E bot hadrons is calculated and its connection with the BFKL cross section is discussed. (orig.)

  3. Deep-inelastic electroproduction of neutrons in the proton fragmentation region

    International Nuclear Information System (INIS)

    Kopeliovich, B.; Povh, B.; Potashnikova, I.

    1996-01-01

    Experiments at HERA looking for deep-inelastic electroproduction of neutrons in the proton fragmentation region are in process. They are aimed to measure the pion structure function at small Bjorken x. The important condition for such a study is to establish under what kinematical conditions the dominance of the pion-pole graph in the process is guaranteed. We analyse other sources of the leading neutron, in order to figure out the kinematical region where the one-pion exchange dominates. (orig.)

  4. Nucleon Resonance Structure from Exclusive Meson Electroproduction with CLAS and CLAS12

    Energy Technology Data Exchange (ETDEWEB)

    Cole, P.L. [Idaho State University, Department of Physics, Pocatello, Idaho 83209-8106 (United States); Burkert, V.D. [Jefferson Lab., 12000 Jefferson Ave., Newport News, VA 23606 (United States); Gothe, R.W. [University of South Carolina, Department of Physics, Columbia, South Carolina 29208 (United States); Mokeev, V.I. [Jefferson Lab., 12000 Jefferson Ave., Newport News, VA 23606 (United States); Skobeltsyn Nuclear Physics Institute, Moscow State University, 119899 Moscow (Russian Federation)

    2012-12-15

    The CLAS detector at Jefferson Lab is a unique instrument, which has provided the lion's share of the world's data on meson photo- and electroproduction in the resonance excitation region. The electroexcitation amplitudes for the low-lying resonances P{sub 33}(1232), P{sub 11}(1440), D{sub 13}(1520), and S{sub 11}(1535) were determined over a wide range of Q{sup 2}<5.0GeV{sup 2} in a comprehensive analysis of exclusive single-meson (π{sup +}n,π{sup 0}p) reactions in the electroproduction off protons. Further, CLAS was able to precisely measure π{sup +}π{sup −}p electroproduction differential cross sections provided by the nearly full kinematic coverage of the detector. The electrocouplings of the P{sub 11}(1440) and D{sub 13}(1520) excited states are determined from the exclusive-π{sup +}π{sup −}p reaction. Consistent results on the electrocouplings from two-independent analyses (single- and double-pion electroproduction) have provided compelling evidence for the reliable extraction of the N{sup ⁎} electrocouplings. Preliminary results on the electrocouplings of the S{sub 31}(1620), S{sub 11}(1650), D{sub 33}(1700), and P{sub 13}(1720) states have recently become available. Theoretical analyses of these results have revealed that there are two major contributions to the resonance structure: a) an internal quark core and b) an external meson-baryon cloud. These CLAS results have had considerable impact on QCD-based studies on N{sup ⁎} structure and in the search for manifestations of the dynamical masses of the dressed quarks. Future CLAS12 N{sup ⁎} structure studies at high photon virtualities will considerably extend our capabilities in exploring the nature of confinement in baryons.

  5. Photo- and electro-production of pseudoscalar mesons at high energies

    International Nuclear Information System (INIS)

    Guidal, M.; Laget, J.M.; Vanderhaeghen, M.

    1998-01-01

    A low momentum transfer Regge-based model for pseudoscalar meson photoproduction is presented. For pions, data are relatively numerous and permit to build a consistent and reliable model which is gauge invariant and whose parameters are well determined by the precise studies and analyses in the resonance region. Subsequently, the model was extended in a straightforward fashion to the case of electroproduction where it can be useful to extract the mesons form factors

  6. Beam helicity asymmetries in K+Lambda electroproduction off the proton at low Q(2)

    Czech Academy of Sciences Publication Activity Database

    Achenbach, P.; Gayoso, C. A.; Böhm, R.; Borodina, O.; Bosnar, D.; Bozkurt, V.; Bydžovský, Petr; Debenjak, L.; Distler, M. O.; Esser, A.; Friscic, I.; Fujii, Y.; Gogami, T.; Rodriguez, M. G.; Hashimoto, O.; Hirose, S.; Kanda, H.; Kaneta, M.; Kim, E.; Margaryan, A.; Merkel, H.; Müller, U.; Nagao, S.; Nakamura, S. N.; Pochodzalla, J.; Rappold, C.; Reinhold, J.; Saito, T. R.; Lorente, A.S.; Majos, S. S.; Schlimme, B. S.; Schoth, M.; Schulz, F.; Sfienti, C.; Sirca, S.; Skoupil, Dalibor; Tang, L.; Thiel, M.; Tsukada, K.

    2017-01-01

    Roč. 53, č. 10 (2017), č. článku 198. ISSN 1434-6001 R&D Projects: GA ČR(CZ) GA15-04301S Institutional support: RVO:61389005 Keywords : electroproduction * MAMI * higher four-momentum transfers Subject RIV: BE - Theoretical Physics OBOR OECD: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect) Impact factor: 2.833, year: 2016

  7. Nucleon resonance electroproduction at high momentum transers: Results from SLAC and suggestions for CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    Keppel, C. [Virginia Union Univ., Richmond, VA (United States)

    1994-04-01

    Nucleon resonance electroproduction results from SLAC Experiment E14OX are presented. A CEBAF facility with doubled energy would enable similar high momentum transfer measurements to be made with greater accuracy. Of particular interest are the Delta P{sub 33}(1232) resonance form factor and R = {sigma}{sub L}/{sigma}{sub T}, the ratio of the longitudinal and transverse components of the cross section. A suggestion is made to study these quantities in conjunction with Bloom-Gilman duality.

  8. Exclusive electroproduction of lepton pairs as a probe of nucleon structure

    International Nuclear Information System (INIS)

    Belitsky, A.V.; Mueller, D.

    2003-01-01

    We suggest the measurement of exclusive electroproduction of lepton pairs as a tool to study interparton correlations in the nucleon via generalized parton distributions in the kinematical region where this process is light-cone dominated. We demonstrate how the single beam-spin asymmetry allows one to perform such a kind of analysis and give a number of predictions for several experimental setups. We comment on other observables which allow for a clean separation of different species of generalized parton distributions

  9. Associated Λ/Σ0 electroproduction with the Kaos spectrometer at MAMI

    Directory of Open Access Journals (Sweden)

    Achenbach P.

    2010-04-01

    Full Text Available An instrument of central importance for the strangeness photo- and electroproduction at the 1.5 GeV ¨ electron beam of the MAMI accelerator at the Institut fur Kernphysik in Mainz, Germany, is the newly installed magnetic spectrometer KAOS that is operated by the A1 collaboration in (e, e′ K reactions on the proton or light nuclei. Its compact design and its capability to detect negative and positive charged particles simultaneously complements the existing spectrometers. The strangeness program performed with Kaos in 2008–9 is addressing some important issues in the field of elementary kaon photo- and electroproduction reactions. Although recent measurements have been performed at Jefferson Lab, there are still a number of open problems in the interpretation of the data and the description of the elementary process using phenomenological models. With the identification of Λ and Σ0 hyperons in the missing mass spectra from kaon production off a liquid hydrogen target it is demonstrated that the extended facility at MAMI is capable to perform strangeness electroproduction spectroscopy at low momentum transfers Q2 < 0.5 (GeV/c2 . The covered kinematics and systematic uncertainties in the cross-section extraction from the data are discussed.

  10. First observation of the decay $\\bar{B}^0_s \\to D^0 K^{*0}$ and a measurement of the ratio of branching fractions $\\frac{{\\cal B}(\\bar{B}^0_s \\to D^0 K^{*0})}{{\\cal B}(\\bar{B}^0 \\to D^0 \\rho^0)}$

    CERN Document Server

    Aaij, R; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amhis, Y; Anderson, J; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Arrabito, L; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Bailey, D S; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bates, A; Bauer, C; Bauer, Th; Bay, A; Bediaga, I; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Brisbane, S; Britsch, M; Britton, T; Brook, N H; Brown, H; Büchler-Germann, A; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Caicedo Carvajal, J M; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Charles, M; Charpentier, Ph; Chiapolini, N; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Collins, P; Comerma-Montells, A; Constantin, F; Conti, G; Contu, A; Cook, A; Coombes, M; Corti, G; Cowan, G A; Currie, R; D'Almagne, B; D'Ambrosio, C; David, P; De Bonis, I; De Capua, S; De Cian, M; De Lorenzi, F; De Miranda, J M; De Paula, L; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Deissenroth, M; Del Buono, L; Deplano, C; Deschamps, O; Dettori, F; Dickens, J; Dijkstra, H; Diniz Batista, P; Domingo Bonal, F; Donleavy, S; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisele, F; Eisenhardt, S; Ekelhof, R; Eklund, L; Elsasser, Ch; d'Enterria, D G; Esperante Pereira, D; Estéve, L; Falabella, A; Fanchini, E; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Fernandez Albor, V; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Frank, M; Frei, C; Frosini, M; Furcas, S; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garnier, J-C; Garofoli, J; Garra Tico, J; Garrido, L; Gascon, D; Gaspar, C; Gauvin, N; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Haefeli, G; Haen, C; Haines, S C; Hampson, T; Hansmann-Menzemer, S; Harji, R; Harnew, N; Harrison, J; Harrison, P F; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Hofmann, W; Holubyev, K; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Huston, R S; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Imong, J; Jacobsson, R; Jaeger, A; Jahjah Hussein, M; Jans, E; Jansen, F; Jaton, P; Jean-Marie, B; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kandybei, S; Karacson, M; Karbach, T M; Keaveney, J; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kim, Y M; Knecht, M; Koblitz, S; Koppenburg, P; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kruzelecki, K; Kucharczyk, M; Kukulak, S; Kumar, R; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Le Gac, R; van Leerdam, J; Lees, J-P; Lefévre, R; Leflat, A; Lefrançois, J; Leroy, O; Lesiak, T; Li, L; Li Gioi, L; Lieng, M; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Luisier, J; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Magnin, J; Malde, S; Mamunur, R M D; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinez Santos, D; Massafferri, A; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Maynard, B; Mazurov, A; McGregor, G; McNulty, R; Mclean, C; Meissner, M; Merk, M; Merkel, J; Messi, R; Miglioranzi, S; Milanes, D A; Minard, M-N; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Musy, M; Mylroie-Smith, J; Naik, P; Nakada, T; Nandakumar, R; Nardulli, J; Nasteva, I; Nedos, M; Needham, M; Neufeld, N; Nguyen-Mau, C; Nicol, M; Nies, S; Niess, V; Nikitin, N; Nomerotski, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, K; Palacios, J; Palano, A; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Paterson, S K; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perego, D L; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pessina, G; Petrella, A; Petrolini, A; Picatoste Olloqui, E; Pie Valls, B; Pietrzyk, B; Pilar, T; Pinci, D; Plackett, R; Playfer, S; Plo Casasus, M; Polok, G; Poluektov, A; Polycarpo, E; Popov, D; Popovici, B; Potterat, C; Powell, A; du Pree, T; Prisciandaro, J; Pugatch, V; Puig Navarro, A; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rangel, M S; Raniuk, I; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Rinnert, K; Roa Romero, D A; Robbe, P; Rodrigues, E; Rodrigues, F; Rodriguez Perez, P; Rogers, G J; Roiser, S; Romanovsky, V; Rosello, M; Rouvinet, J; Ruf, T; Ruiz, H; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salzmann, C; Sannino, M; Santacesaria, R; Santinelli, R; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Savrina, D; Schaack, P; Schiller, M; Schleich, S; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M -H; Schwemmer, R; Sciascia, B; Sciubba, A; Seco, M; Semennikov, A; Senderowska, K; Sepp, I; Serra, N; Serrano, J; Seyfert, P; Shao, B; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Skottowe, H P; Skwarnicki, T; Smith, A C; Smith, N A; Smith, E; Sobczak, K; Soler, F J P; Solomin, A; Soomro, F; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, S; Steinkamp, O; Stoica, S; Stone, S; Storaci, B; Straticiuc, M; Straumann, U; Styles, N; Subbiah, V K; Swientek, S; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teodorescu, E; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Topp-Joergensen, S; Torr, N; Tran, M T; Tsaregorodtsev, A; Tuning, N; Ukleja, A; Urquijo, P; Uwer, U; Vagnoni, V; Valenti, G; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; Velthuis, J J; Veltri, M; Vervink, K; Viaud, B; Videau, I; Vilasis-Cardona, X; Visniakov, J; Vollhardt, A; Voong, D; Vorobyev, A; Voss, H; Wacker, K; Wandernoth, S; Wang, J; Ward, D R; Webber, A D; Websdale, D; Whitehead, M; Wiedner, D; Wiggers, L; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wishahi, J; Witek, M; Witzeling, W; Wotton, S A; Wyllie, K; Xie, Y; Xing, F; Xing, Z; Yang, Z; Young, R; Yushchenko, O; Zavertyaev, M; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhong, L; Zverev, E; Zvyagin, A

    2011-01-01

    The first observation of the decay $\\bar{B}^0_s \\to D^0 K^{*0}$ using $pp$ data collected by the LHCb detector at a centre-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 36 pb$^{-1}$, is reported. A signal of $34.4 \\pm 6.8$ events is obtained and the absence of signal is rejected with a statistical significance of more than nine standard deviations. The $\\bar{B}^0_s \\to D^0 K^{*0}$ branching fraction is measured relative to that of $\\bar{B}^0 \\to D^0 \\rho^0$: $\\frac{{\\cal B}(\\bar{B}^0_s \\to D^0 K^{*0})}{{\\cal B}(\\bar{B}^0 \\to D^0 \\rho^0)} = 1.48 \\pm 0.34 \\pm 0.15 \\pm 0.12$, where the first uncertainty is statistical, the second systematic and the third is due to the uncertainty on the ratio of the $B^0$ and $B^0_s$ hadronisation fractions.

  11. Near threshold electroproduction of the ω meson at Q2≅0.5 GeV2

    International Nuclear Information System (INIS)

    Ambrozewicz, P.; Mitchell, J.; Dunne, J.; Abbott, D.J.; Carlini, R.; Ent, R.; Mack, D.J.; Wood, S.; Yan, C.; Markowitz, P.; Martoff, C.J.; Reinhold, J.; Zeidman, B.; Arrington, J.; Bailey, K.; Cummings, W.J.; Gao, H.; Geesaman, D.F.; Hansen, J.-O.; O'Neill, T.G.

    2004-01-01

    Electroproduction of the ω meson was investigated in the 1 H(e,e ' p)ω reaction. The measurement was performed at a four-momentum transfer Q 2 ≅0.5 GeV 2 . Angular distributions of the virtual photon-proton center-of-momentum cross sections have been extracted over the full angular range. These distributions exhibit a strong enhancement over t-channel parity exchange processes in the backward direction. According to a newly developed electroproduction model, this enhancement provides significant evidence of resonance formation in the γ*p→ωp reaction channel

  12. Near threshold electroproduction of the omega meson at Q2 ∼ 0.5 GeV2

    International Nuclear Information System (INIS)

    Ambrozewicz, P.; Mitchell, J.; Dunne, J.; Markowitz, P.; Martoff, C. J.; Reinhold, J.; Zeidman, B.

    2004-01-01

    Electroproduction of the omega meson was investigated in the p(e,e'p)omega reaction. The measurement was performed at a 4-momentum transfer Q2 ∼ 0.5 GeV2. Angular distributions of the virtual photon-proton center-of-momentum cross sections have been extracted over the full angular range. These distributions exhibit a strong enhancement over t-channel parity exchange processes in the backward direction. According to a newly developed electroproduction model, this enhancement provides significant evidence of resonance formation in the gamma* p -> omega p reaction channel

  13. Diffractive electroproduction of s{bar s} mesons off nuclei at CEBAF energies

    Energy Technology Data Exchange (ETDEWEB)

    Benhar, O. [Instituto Superiore di Sanita, Roma (Italy); Nikolaev, N.N.; Zakharov, B.G. [L.D. Landau Inst. for Theoretical Physics, Juelich (Germany)] [and others

    1994-04-01

    The authors discuss diffractive incoherent electroproduction of s{bar s} mesons off nuclear targets at beam energies that are expected to be available at CEBAF (5-8 GeV). The Q{sup 2} and target mass dependence of the {phi} and {phi}{prime} transparency ratios has been studied within a theoretical approach in which the propagation of the s{bar s} pair through the nuclear medium is described in terms of the quantum mechanical evolution operator. The authors predict a complex pattern of nuclear effects, whose experimental study may provide information on several issues relevant to the understanding of QCD, both in the perturbative and nonperturbative regimes.

  14. J/Ψ and φ Electro-production in Pomeron Exchange Model

    International Nuclear Information System (INIS)

    Liu Baorong; Tan Zhenqiang; Gu Yunting; He Xiaorong; Zhou Lijuan; Ma Weixing

    2007-01-01

    Based on Pomeron exchange model, J/Ψ and φ production in electro-proton interaction are investigated with both linear and non-linear Pomeron trajectory. The experimental differential cross sections measured as a function of the kinematic variable Q 2 ,W and t are reproduced successfully in the model. Our conclusions are that the Pomeron exchange model is a successful description of J/Ψ and φ electro-productions on the proton, and that the linear trajectory is a good approximation to non-linearity of the Pomeron trajectory.

  15. Q2 Dependence of Nuclear Transparency for Incoherent ρ0 Electroproduction

    International Nuclear Information System (INIS)

    John Arrington; Frank Dohrmann; Ahmed El Alaoui; Don Geesaman; Kawtar Hafidi; Roy Holt; Harold Jackson; David Potterveld; Brahim Mustapha; Paul Reimer; Elaine Schulte; Krishni Wijesooriya; Maurik Holtrop; Jacques Ball; Michel Garcon; Jean Laget; Franck Sabatie; Michel Guidal; Latifa Elouadrhiri; Borissov, A.; Wolfgang Lorenzon; Stepan Stepanyan; Lawrence Weinstein

    2002-01-01

    Measurements of exclusive incoherent electroproduction of ρ 0 (770) meson from 2 D, 12 C, and 63 Cu targets up to Q 2 = 4 GeV 2 are proposed using the CLAS detector. The objective of these measurements is to determine the Q 2 dependence of the nuclear transparency ratio for the two nuclear targets: 12 C and 63 Cu at fixed coherence length of quark-antiquark fluctuations of the virtual photon. A sizeable rise of the nuclear transparency is predicted and can be measured in this experiment. A relatively large increase of the nuclear transparency can be considered as a signature of the onset of color transparency

  16. Pion electroproduction at threshold on the nucleon. Contribution to the measurement of the nucleon form factor

    International Nuclear Information System (INIS)

    Duval, M.A.

    1989-11-01

    A pion electroproduction experiment is discussed. The experiment is carried out at threshold on the proton, at the Saclay Linear Accelerator. The scattered electron and the produced pion are detected in coincidence. The aim of the investigation is to measure the nucleon axial form factor. Theoretical concepts and previous experiments are reviewed. The experimental set-up is described, in particular the new pion arm and the trigger simulation. The preliminary analysis of six kinematical points at the momentum transfer of two inverse fermis squared shows the feasibility of the experiment. The pions detection and their identification are satisfactory and allow measurements to be performed [fr

  17. A note on color magnetism models and the electroproduction of the Δ(1232)

    International Nuclear Information System (INIS)

    Rondon-Aramayo, O.A.

    1989-01-01

    In this work the author discusses the experimental consequences of the use of the color magnetism concept in non-relativistic quark models of the nucleon and its resonances. It is found that the application of this model to the electroproduction of the Δ (1232) resonance does not give satisfactory agreement with well established experimental results for the γN → Δ or γυ N → Δ processes. Some of the reasons for the disagreement are considered and an alternative approach is suggested

  18. Rosenbluth separation of the $\\pi^0$ Electroproduction Cross Section off the Neutron

    OpenAIRE

    Mazouz, M.; Ahmed, Z.; Albataineh, H.; Allada, K.; Aniol, K. A.; Bellini, V.; Benali, M.; Boeglin, W.; Bertin, P.; Brossard, M.; Camsonne, A.; Canan, M.; Chandavar, S.; Chen, C.; Chen, J. -P.

    2017-01-01

    We report the first longitudinal/transverse separation of the deeply virtual exclusive $\\pi^0$ electroproduction cross section off the neutron and coherent deuteron. The corresponding four structure functions $d\\sigma_L/dt$, $d\\sigma_T/dt$, $d\\sigma_{LT}/dt$ and $d\\sigma_{TT}/dt$ are extracted as a function of the momentum transfer to the recoil system at $Q^2$=1.75 GeV$^2$ and $x_B$=0.36. The $ed \\to ed\\pi^0$ cross sections are found compatible with the small values expected from theoretical...

  19. First observation of the decay $\\bar{B}^0_s \\to D^0 K^{*0}$ and measurement of the ratio of branching fractions $\\frac{\\mathcal{B}(\\bar{B}^0_s \\to D^0 K^{*0})}{\\mathcal{B}(\\bar{B}^0 \\to D^0\\rho^0)}$ with the LHCb experiment at $\\sqrt{s}$ = 7 TeV

    CERN Multimedia

    Martens, A

    2011-01-01

    In 36 pb$^{-1}$ of $pp$ collisions at a centre-of-mass energy $\\sqrt{s}$ = 7 TeV, we observe for the first time the decay $\\bar{B}^0_s \\to D^0 K^{*0}$. The $\\bar{B}^0_s \\to D^0 K^{*0}$ decay mode is a potentially dangerous background for the Cabibbo suppressed decay $B^0 \\to \\bar{D}^0 K^{*0}$ used in the measurement of the CKM angle $\\gamma$. A clear signal of 34.5$\\pm$6.9 events is obtained with a statistical significance over 9 standard deviations and we measure its branching ration relative to the $\\bar{B}^0 \\to D^0\\rho^0$ branching ratio.

  20. The asymmetry in electroproduction of the Δ(1232) by polarized electrons and the structure of the weak neutral current

    International Nuclear Information System (INIS)

    Hossain, A.; Chaudhury, T.K.; Nath, L.M.

    1983-08-01

    The R-L asymmetry in electroproduction of the Δ(1232) by longitudinally polarized electrons, which is, a priori, a parity violating effect, has been discussed in the framework of the SU(2)xU(1) symmetry. Our predictions are related to and expected to be useful in the determination of the structure of the weak neutral current. (author)

  1. Photon and π"0 electroproduction at Jefferson Laboratory-Hall A

    International Nuclear Information System (INIS)

    Defurne, Maxime

    2015-01-01

    Defined in the mid 90's, the generalized parton distributions (GPDs) represent a higher level of information than the form factors and parton distribution functions: indeed they encapsulate the correlation between the fraction of longitudinal momentum and the transverse position of the partons inside the nucleon. Consequently we can access the distribution of the partons in the transverse plane according to their longitudinal momentum. Moreover we can derive the total angular orbital momentum of quarks thanks to Ji's sum rule. Experimentally, we access the GPDs through the study of deep exclusive processes (asymmetries, cross sections,...). A worldwide experimental program started in the early 2000's. This thesis presents two data analyses carried on two data sets from experiments running at Jefferson laboratory - Hall A in 2004 and 2010. From the 2004 data set, we have extracted unpolarized and polarized photon electroproduction cross sections. A careful study of the systematic errors has greatly improved the quality of the results. They seem to indicate the necessity to take into account target-mass and finite-t corrections up to twist-4. From the 2010 data set, we have performed the first separation of the longitudinal and transverse responses of neutral pion electroproduction. The results confirm the assumption of a significant contribution of the transverse response although kinematically suppressed with respect to the longitudinal response. These results of high precision validate the GPD approach and will allow to improve the existing models. (author) [fr

  2. Meson (photo- and) electro-production and the structure of nuclei at short distances

    International Nuclear Information System (INIS)

    Laget, J.M.

    1985-09-01

    The present status and the future prospects of the studies of very inelastic electronuclear reaction are reviewed, when both high energy and high momentum are transferred to the nucleus. Real and virtual mesons are tested on the same footing. Real meson production allows us to study the propagation of baryonic and mesonic resonances in nuclei and to put constraints on their interaction with the nucleon. Virtual meson creation is an alternative way to deal with exchange currents. The first lecture deals with the elementary operators, which describe meson photo- and electroproduction on free nucleons. The second one deals with real meson- photo- and electroproduction on few-body systems. Only the main features are discussed here and the last developments are presented. The third lecture deals with the coupling of the electromagnetic probe to the virtual meson in nuclei. The emphasis is put on the few-body systems, since their nuclear wave functions are known and since they are simple enough to allow for elaborate calculations. The case of heavy nuclei is also discussed. In the last lecture, I will try to look for evidence of the limits and the breakdown of the description of nuclei in terms of nucleons and mesons, and to forecast the new developments

  3. Rosenbluth Separation of the π^{0} Electroproduction Cross Section Off the Neutron.

    Science.gov (United States)

    Mazouz, M; Ahmed, Z; Albataineh, H; Allada, K; Aniol, K A; Bellini, V; Benali, M; Boeglin, W; Bertin, P; Brossard, M; Camsonne, A; Canan, M; Chandavar, S; Chen, C; Chen, J-P; Defurne, M; de Jager, C W; de Leo, R; Desnault, C; Deur, A; El Fassi, L; Ent, R; Flay, D; Friend, M; Fuchey, E; Frullani, S; Garibaldi, F; Gaskell, D; Giusa, A; Glamazdin, O; Golge, S; Gomez, J; Hansen, O; Higinbotham, D; Holmstrom, T; Horn, T; Huang, J; Huang, M; Huber, G M; Hyde, C E; Iqbal, S; Itard, F; Kang, Ho; Kang, Hy; Kelleher, A; Keppel, C; Koirala, S; Korover, I; LeRose, J J; Lindgren, R; Long, E; Magne, M; Mammei, J; Margaziotis, D J; Markowitz, P; Martí Jiménez-Argüello, A; Meddi, F; Meekins, D; Michaels, R; Mihovilovic, M; Muangma, N; Muñoz Camacho, C; Nadel-Turonski, P; Nuruzzaman, N; Paremuzyan, R; Puckett, A; Punjabi, V; Qiang, Y; Rakhman, A; Rashad, M N H; Riordan, S; Roche, J; Russo, G; Sabatié, F; Saenboonruang, K; Saha, A; Sawatzky, B; Selvy, L; Shahinyan, A; Sirca, S; Solvignon, P; Sperduto, M L; Subedi, R; Sulkosky, V; Sutera, C; Tobias, W A; Urciuoli, G M; Wang, D; Wojtsekhowski, B; Yao, H; Ye, Z; Zana, L; Zhan, X; Zhang, J; Zhao, B; Zhao, Z; Zheng, X; Zhu, P

    2017-06-02

    We report the first longitudinal-transverse separation of the deeply virtual exclusive π^{0} electroproduction cross section off the neutron and coherent deuteron. The corresponding four structure functions dσ_{L}/dt, dσ_{T}/dt, dσ_{LT}/dt, and dσ_{TT}/dt are extracted as a function of the momentum transfer to the recoil system at Q^{2}=1.75  GeV^{2} and x_{B}=0.36. The ed→edπ^{0} cross sections are found compatible with the small values expected from theoretical models. The en→enπ^{0} cross sections show a dominance from the response to transversely polarized photons, and are in good agreement with calculations based on the transversity generalized parton distributions of the nucleon. By combining these results with previous measurements of π^{0} electroproduction off the proton, we present a flavor decomposition of the u and d quark contributions to the cross section.

  4. Measurement of Exclusive $π^0$ Electroproduction Structure Functions and their Relationship to Transverse Generalized Parton Distributions

    Energy Technology Data Exchange (ETDEWEB)

    Bedlinskiy, Ivan; Niccolai, Silvia; Stoler, Paul; Adhikari, Krishna; Aghasyan, Mher; Amaryan, Moskov; Anghinolfi, Marco; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Ball, Jacques; Baltzell, Nathan; Battaglieri, Marco; Bennett, Robert; Biselli, Angela; Bookwalter, Craig; Boyarinov, Sergey; Briscoe, William; Brooks, Williams; Burkert, Volker; Carman, Daniel; Celentano, Andrea; Chandavar, Shloka; Charles, Gabriel; Contalbrigo, Marco; Crede, Volker; D& #x27; Angelo, Annalisa; Daniel, Aji; Dashyan, Natalya; De Vita, Raffaella; De Sanctis, Enzo; Deur, Alexandre; Djalali, Chaden; Doughty, David; Dupre, Raphael; Egiyan, Hovanes; El Alaoui, Ahmed; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fedotov, Gleb; Fegan, Stuart; Fleming, Jamie; Forest, Tony; Garcon, Michel; Gevorgyan, Nerses; Giovanetti, Kevin; Girod, Francoi-Xavier; Gohn, Wesley; Gothe, Ralf; Graham, Lewis; Griffioen, Keith; Guegan, Baptiste; Guidal, Michel; Guo, Lei; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Heddle, David; Hicks, Kenneth; Holtrop, Maurik; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Jo, Hyon-Suk; Joo, Kyungseon; Keller, Dustin; Khanddaker, Mahbubul; Khertarpal, Puneet; Kim, Andrey; Kim, Wooyoung; Klein, Franz; Koirala, Suman; Kubarovsky, A; Kuhn, Sebastian; Kuleshov, Sergey; Kvaltine, Nicholas; Livingston, Kenneth; Lu, Haiyun; MacGregor, Ian; Mao, Yuqing; Markov, Nikolai; Martinez, D; Mayer, Michael; McKinnon, Bryan; Meyer, Curtis; Mineeva, Taisiya; Mirazita, Marco; Mokeev, Viktor; Moutarde, Herve; Munevar Espitia, Edwin; Munoz Camacho, Carlos; Nadel-Turonski, Pawel; Niculescu, Gabriel; Niculescu, Maria-Ioana; Osipenko, Mikhail; Ostrovidov, Alexander; Pappalardo, Luciano; Permuzyan, Rafayel; Park, Kijun; Park, Sungkyun; Pasyuk, Eugene; Pereira, Sergio; Phelps, Evan; Pisano, Silvia; Pogorelko, Oleg; Pozdnyakov, Sergey; Price, John; Procureur, Sebastien; Prok, Yelena; Protopopescu, Dan; Puckett, Andrew; Raue, Brian; Ricco, Giovanni; Rimal, Dipak; Ripani, Marco; Rosner, Guenther; Rossi, Patrizia; Sabatie, Franck; Saini, Mukesh; Salgado, Carlos; Saylor, Nicholas; Schott, Diane; Schumacher, Reinhard; Seder, Erin; Seraydaryan, Heghine; Sharabian, Youri; Smith, Gregory; Sober, Daniel; Sokhan, Daria; Stepanyan, Samuel; Strauch, Steffen; Taiuti, Mauro; Tang, Wei; Taylor, Charles; Tian, Ye; Tkachenko, Svyatoslav; Ungaro, Maurizio; Vineyard, Michael; Vlasov, Alexander; Voskanyan, Hakob; Voutier, Eric; Walford, Natalie; Watts, Daniel; Weinstein, Lawrence; Weygan, Dennis; Wood, Michael; Zachariou, Nicholas; Zhang, Jixie; Zhao, Zhiwen

    2012-09-01

    Exclusive $\\pi^0$ electroproduction at a beam energy of 5.75 GeV has been measured with the Jefferson Lab CLAS spectrometer. Differential cross sections were measured at more than 1800 kinematic values in $Q^2$, $x_B$, $t$, and $\\phi_\\pi$, in the $Q^2$ range from 1.0 to 4.6 GeV$^2$,\\ $-t$ up to 2 GeV$^2$, and $x_B$ from 0.1 to 0.58. Structure functions $\\sigma_T +\\epsilon \\sigma_L, \\sigma_{TT}$ and $\\sigma_{LT}$ were extracted as functions of $t$ for each of 17 combinations of $Q^2$ and $x_B$. The data were compared directly with two handbag-based calculations including both longitudinal and transversity GPDs. Inclusion of only longitudinal GPDs very strongly underestimates $\\sigma_T +\\epsilon \\sigma_L$ and fails to account for $\\sigma_{TT}$ and $\\sigma_{LT}$, while inclusion of transversity GPDs brings the calculations into substantially better agreement with the data. There is very strong sensitivity to the relative contributions of nucleon helicity flip and helicity non-flip processes. The results confirm that exclusive $\\pi^0$ electroproduction offers direct experimental access to the transversity GPDs.

  5. Measurement of exclusive π(0) electroproduction structure functions and their relationship to transverse generalized parton distributions.

    Science.gov (United States)

    Bedlinskiy, I; Kubarovsky, V; Niccolai, S; Stoler, P; Adhikari, K P; Aghasyan, M; Amaryan, M J; Anghinolfi, M; Avakian, H; Baghdasaryan, H; Ball, J; Baltzell, N A; Battaglieri, M; Bennett, R P; Biselli, A S; Bookwalter, C; Boiarinov, S; Briscoe, W J; Brooks, W K; Burkert, V D; Carman, D S; Celentano, A; Chandavar, S; Charles, G; Contalbrigo, M; Crede, V; D'Angelo, A; Daniel, A; Dashyan, N; De Vita, R; De Sanctis, E; Deur, A; Djalali, C; Doughty, D; Dupre, R; Egiyan, H; El Alaoui, A; El Fassi, L; Elouadrhiri, L; Eugenio, P; Fedotov, G; Fegan, S; Fleming, J A; Forest, T A; Fradi, A; Garçon, M; Gevorgyan, N; Giovanetti, K L; Girod, F X; Gohn, W; Gothe, R W; Graham, L; Griffioen, K A; Guegan, B; Guidal, M; Guo, L; Hafidi, K; Hakobyan, H; Hanretty, C; Heddle, D; Hicks, K; Holtrop, M; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Jo, H S; Joo, K; Keller, D; Khandaker, M; Khetarpal, P; Kim, A; Kim, W; Klein, F J; Koirala, S; Kubarovsky, A; Kuhn, S E; Kuleshov, S V; Kvaltine, N D; Livingston, K; Lu, H Y; MacGregor, I J D; Mao, Y; Markov, N; Martinez, D; Mayer, M; McKinnon, B; Meyer, C A; Mineeva, T; Mirazita, M; Mokeev, V; Moutarde, H; Munevar, E; Munoz Camacho, C; Nadel-Turonski, P; Niculescu, G; Niculescu, I; Osipenko, M; Ostrovidov, A I; Pappalardo, L L; Paremuzyan, R; Park, K; Park, S; Pasyuk, E; Anefalos Pereira, S; Phelps, E; Pisano, S; Pogorelko, O; Pozdniakov, S; Price, J W; Procureur, S; Prok, Y; Protopopescu, D; Puckett, A J R; Raue, B A; Ricco, G; Rimal, D; Ripani, M; Rosner, G; Rossi, P; Sabatié, F; Saini, M S; Salgado, C; Saylor, N; Schott, D; Schumacher, R A; Seder, E; Seraydaryan, H; Sharabian, Y G; Smith, G D; Sober, D I; Sokhan, D; Stepanyan, S S; Stepanyan, S; Strauch, S; Taiuti, M; Tang, W; Taylor, C E; Tian, Ye; Tkachenko, S; Ungaro, M; Vineyard, M F; Vlassov, A; Voskanyan, H; Voutier, E; Walford, N K; Watts, D P; Weinstein, L B; Weygand, D P; Wood, M H; Zachariou, N; Zhang, J; Zhao, Z W; Zonta, I

    2012-09-14

    Exclusive π(0) electroproduction at a beam energy of 5.75 GeV has been measured with the Jefferson Lab CLAS spectrometer. Differential cross sections were measured at more than 1800 kinematic values in Q(2), x(B), t, and ϕ(π), in the Q(2) range from 1.0 to 4.6  GeV(2), -t up to 2  GeV(2), and x(B) from 0.1 to 0.58. Structure functions σ(T)+ϵσ(L), σ(TT), and σ(LT) were extracted as functions of t for each of 17 combinations of Q(2) and x(B). The data were compared directly with two handbag-based calculations including both longitudinal and transversity generalized parton distributions (GPDs). Inclusion of only longitudinal GPDs very strongly underestimates σ(T)+ϵσ(L) and fails to account for σ(TT) and σ(LT), while inclusion of transversity GPDs brings the calculations into substantially better agreement with the data. There is very strong sensitivity to the relative contributions of nucleon helicity-flip and helicity nonflip processes. The results confirm that exclusive π(0) electroproduction offers direct experimental access to the transversity GPDs.

  6. Measurement of Exclusive π0 Electroproduction Structure Functions and their Relationship to Transverse Generalized Parton Distributions

    Science.gov (United States)

    Bedlinskiy, I.; Kubarovsky, V.; Niccolai, S.; Stoler, P.; Adhikari, K. P.; Aghasyan, M.; Amaryan, M. J.; Anghinolfi, M.; Avakian, H.; Baghdasaryan, H.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Bennett, R. P.; Biselli, A. S.; Bookwalter, C.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Daniel, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Doughty, D.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fleming, J. A.; Forest, T. A.; Fradi, A.; Garçon, M.; Gevorgyan, N.; Giovanetti, K. L.; Girod, F. X.; Gohn, W.; Gothe, R. W.; Graham, L.; Griffioen, K. A.; Guegan, B.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Heddle, D.; Hicks, K.; Holtrop, M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jo, H. S.; Joo, K.; Keller, D.; Khandaker, M.; Khetarpal, P.; Kim, A.; Kim, W.; Klein, F. J.; Koirala, S.; Kubarovsky, A.; Kuhn, S. E.; Kuleshov, S. V.; Kvaltine, N. D.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Mao, Y.; Markov, N.; Martinez, D.; Mayer, M.; McKinnon, B.; Meyer, C. A.; Mineeva, T.; Mirazita, M.; Mokeev, V.; Moutarde, H.; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Pappalardo, L. L.; Paremuzyan, R.; Park, K.; Park, S.; Pasyuk, E.; Anefalos Pereira, S.; Phelps, E.; Pisano, S.; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Ricco, G.; Rimal, D.; Ripani, M.; Rosner, G.; Rossi, P.; Sabatié, F.; Saini, M. S.; Salgado, C.; Saylor, N.; Schott, D.; Schumacher, R. A.; Seder, E.; Seraydaryan, H.; Sharabian, Y. G.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Stepanyan, S. S.; Stepanyan, S.; Strauch, S.; Taiuti, M.; Tang, W.; Taylor, C. E.; Tian, Ye; Tkachenko, S.; Ungaro, M.; Vineyard, M. F.; Vlassov, A.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Weinstein, L. B.; Weygand, D. P.; Wood, M. H.; Zachariou, N.; Zhang, J.; Zhao, Z. W.; Zonta, I.

    2012-09-01

    Exclusive π0 electroproduction at a beam energy of 5.75 GeV has been measured with the Jefferson Lab CLAS spectrometer. Differential cross sections were measured at more than 1800 kinematic values in Q2, xB, t, and ϕπ, in the Q2 range from 1.0 to 4.6GeV2, -t up to 2GeV2, and xB from 0.1 to 0.58. Structure functions σT+ɛσL, σTT, and σLT were extracted as functions of t for each of 17 combinations of Q2 and xB. The data were compared directly with two handbag-based calculations including both longitudinal and transversity generalized parton distributions (GPDs). Inclusion of only longitudinal GPDs very strongly underestimates σT+ɛσL and fails to account for σTT and σLT, while inclusion of transversity GPDs brings the calculations into substantially better agreement with the data. There is very strong sensitivity to the relative contributions of nucleon helicity-flip and helicity nonflip processes. The results confirm that exclusive π0 electroproduction offers direct experimental access to the transversity GPDs.

  7. Rosenbluth Separation of the π0 Electroproduction Cross Section Off the Neutron

    Science.gov (United States)

    Mazouz, M.; Ahmed, Z.; Albataineh, H.; Allada, K.; Aniol, K. A.; Bellini, V.; Benali, M.; Boeglin, W.; Bertin, P.; Brossard, M.; Camsonne, A.; Canan, M.; Chandavar, S.; Chen, C.; Chen, J.-P.; Defurne, M.; de Jager, C. W.; de Leo, R.; Desnault, C.; Deur, A.; El Fassi, L.; Ent, R.; Flay, D.; Friend, M.; Fuchey, E.; Frullani, S.; Garibaldi, F.; Gaskell, D.; Giusa, A.; Glamazdin, O.; Golge, S.; Gomez, J.; Hansen, O.; Higinbotham, D.; Holmstrom, T.; Horn, T.; Huang, J.; Huang, M.; Huber, G. M.; Hyde, C. E.; Iqbal, S.; Itard, F.; Kang, Ho.; Kang, Hy.; Kelleher, A.; Keppel, C.; Koirala, S.; Korover, I.; LeRose, J. J.; Lindgren, R.; Long, E.; Magne, M.; Mammei, J.; Margaziotis, D. J.; Markowitz, P.; Martí Jiménez-Argüello, A.; Meddi, F.; Meekins, D.; Michaels, R.; Mihovilovic, M.; Muangma, N.; Muñoz Camacho, C.; Nadel-Turonski, P.; Nuruzzaman, N.; Paremuzyan, R.; Puckett, A.; Punjabi, V.; Qiang, Y.; Rakhman, A.; Rashad, M. N. H.; Riordan, S.; Roche, J.; Russo, G.; Sabatié, F.; Saenboonruang, K.; Saha, A.; Sawatzky, B.; Selvy, L.; Shahinyan, A.; Sirca, S.; Solvignon, P.; Sperduto, M. L.; Subedi, R.; Sulkosky, V.; Sutera, C.; Tobias, W. A.; Urciuoli, G. M.; Wang, D.; Wojtsekhowski, B.; Yao, H.; Ye, Z.; Zana, L.; Zhan, X.; Zhang, J.; Zhao, B.; Zhao, Z.; Zheng, X.; Zhu, P.; Jefferson Lab Hall A Collaboration

    2017-06-01

    We report the first longitudinal-transverse separation of the deeply virtual exclusive π0 electroproduction cross section off the neutron and coherent deuteron. The corresponding four structure functions d σL/d t , d σT/d t , d σL T/d t , and d σT T/d t are extracted as a function of the momentum transfer to the recoil system at Q2=1.75 GeV2 and xB=0.36 . The e d →e d π0 cross sections are found compatible with the small values expected from theoretical models. The e n →e n π0 cross sections show a dominance from the response to transversely polarized photons, and are in good agreement with calculations based on the transversity generalized parton distributions of the nucleon. By combining these results with previous measurements of π0 electroproduction off the proton, we present a flavor decomposition of the u and d quark contributions to the cross section.

  8. Study of the p(e,e'π+)n electro-production reaction: form factor and electromagnetic radius of pion

    International Nuclear Information System (INIS)

    Michel, Bernard

    1977-01-01

    After having recalled the definitions and theoretical knowledge on the form factor and electromagnetic radius of hadron and pion, and discussed the relationship between electro-production and form factor for the pion, this research thesis recalls some theoretical aspects of the electro-production process. The author discusses the reaction kinematics and shows how the electro-production cross section can be broken down in terms of photon polarization. Then, he focuses on the cross section dynamic structure. After having recalled the different possible choices for amplitudes, he studies their behaviour, firstly within the framework of the Born approximation, and then within the framework of commonly used models, notably to take the resonant part of the phenomenon into account. The limits of the different models are outlined. The second part addresses the study of forward electro-production. The author shows how the pion form factor can be simply optimized. The author describes the experimental arrangement: electron beam and liquid hydrogen target, detection system, normalisation device, data acquisition logics. In the next chapter, the author describes how data are recorded until the obtainment of N electro-production events. Results are then interpreted in terms of form factor and electromagnetic radius. They are also compared with published results obtained with other electro-production experiments or measurements based on other processes [fr

  9. Double spin asymmetry in exclusive rho(0) muoproduction at COMPASS

    Czech Academy of Sciences Publication Activity Database

    Alekseev, M.; Alexakhin, V. Yu.; Alexandrov, Yu.; Alexeev, G. D.; Amoroso, A.; Arbuzov, A.; Badelek, B.; Balestra, F.; Ball, J.; Baum, G.; Barth, J.; Bedfer, Y.; Bernet, C.; Bertini, R.; Bettinelli, M.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Bravar, A.; Bressan, A.; Brona, G.; Burtin, E.; Bussa, M.; Chapiro, A.; Chiosso, M.; Cicuttin, A.; Colantoni, M.; Costa, S.; Crespo, M.; d'Hose, N.; Dalla Torre, S.; Das, S.; Dasgupta, S. S.; De Masi, R.; Dedek, N.; Denisov, O.; Dhara, L.; Diaz, V.; Dinkelbach, A.; Donskov, S.; Dorofeev, V.; Doshita, N.; Duic, V.; Dünnweber, W.; Eversheim, P.; Eyrich, W.; Fabro, M.; Faessler, M.; Falaleev, V.; Ferrero, A.; Ferrero, L.; Finger, M.; Finger jr., M.; Fischer, H.; Franco, C.; Franz, J.; Friedrich, J.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.; Gazda, R.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gobbo, B.; Goertz, S.; Gorin, A. M.; Grabmüller, S.; Grajek, O.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Haas, F.; Hannappel, J.; von Harrach, D.; Hasegawa, T.; Heckmann, J.; Hedicke, S.; Heinsius, F.; Hermann, R.; Hess, C.; Hinterberger, F.; von Hodenberg, M.; Horikawa, N.; Horikawa, S.; Ilgner, C.; Ioukaev, A.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Janata, A.; Jasinski, P.; Joosten, R.; Jouravlev, N. I.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.; Khokhlov, Y.; Kisselev, Y.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.; Kolosov, V.; Komissarov, E.; Kondo, K.; Königsmann, K.; Konorov, I.; Konstantinov, V.; Korentchenko, A.; Korzenev, A.; Kotzinian, A.; Koutchinski, N.; Kouznetsov, O.; Kravchuk, N.; Kral, A.; Kroumchtein, Z.; Kuhn, R.; Kunne, F.; Kurek, K.; Ladygin, M.; Lamanna, M.; Le Goff, J.; Lednev, A.; Lehmann, A.; Lichtenstadt, J.; Liska, T.; Ludwig, I.; Maggiora, A.; Maggiora, M.; Magnon, A.; Mallot, G.; Mann, A.; Marchand, C.; Marroncle, J.; Martin, A.; Marzec, J.; Massmann, F.; Matsuda, T.; Maximov, A.; Meyer, W.; Mielech, A.; Mikhailov, Y.; Moinester, M.; Mutter, M.; Nähle, O.; Nagaytsev, A.; Nagel, T.; Nassalski, J.; Neliba, S.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.; Nikolaev, K.; Olshevsky, A.; Ostrick, M.; Padee, A.; Pagano, P.; Panebianco, S.; Panknin, R.; Panzieri, D.; Paul, S.; Pawlukiewicz-Kaminska, B.; Peshekhonov, D.; Peshekhonov, V.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.; Pretz, J.; Procureur, S.; Quintans, C.; Rajotte, J.; Rapatsky, V.; Ramos, S.; Reicherz, G.; Richter, A.; Robinet, F.; Rocco, E.; Rondio, E.; Rozhdestvensky, A.; Ryabchikov, D.; Samoylenko, V.; Sandacz, A.; Santos, H.; Sapozhnikov, M.; Sarkar, S.; Savin, I.; Schiavon, P.; Schill, C.; Schmitt, L.; Schönmeier, P.; Schröder, W.; Shevchenko, O.; Siebert, H.; Silva, L.; Sinha, L.; Sissakian, A.; Slunecka, M.; Smirnov, G.; Sosio, S.; Sozzi, F.; Sugonyaev, V.; Srnka, Aleš; Stinzing, F.; Stolarski, M.; Sulc, M.; Sulej, R.; Takabayashi, N.; Tchalishev, V.; Tessaro, S.; Tessarotto, F.; Teufel, A.; Tkatchev, L.; Venugopal, G.; Virius, M.; Vlassov, N.; Vossen, A.; Webb, R.; Weise, E.; Weitzel, Q.; Windmolders, R.; Wirth, S.; Wislicki, W.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Zhao, J.; Ziegler, R.; Zvyagin, A.

    2007-01-01

    Roč. 52, č. 2 (2007), s. 255-265 ISSN 1434-6044 R&D Projects: GA MŠk ME 492 Institutional research plan: CEZ:AV0Z20650511 Keywords : double spin asymmetry * polarized deuterons * scattering * COMPASS Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 3.255, year: 2007

  10. Measurement of Exclusive $\\rho^0 \\rho^0$ Production in Two-Photon Collisions at High $Q^2$ at LEP

    CERN Document Server

    Achard, P.; Aguilar-Benitez, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M.G.; Anderhub, H.; Andreev, Valery P.; Anselmo, F.; Arefev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay, L.; Baldew, S.V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillere, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B.L.; Biasini, M.; Biglietti, M.; Biland, A.; Blaising, J.J.; Blyth, S.C.; Bobbink, G.J.; Bohm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J.G.; Brochu, F.; Burger, J.D.; Burger, W.J.; Cai, X.D.; Capell, M.; Cara Romeo, G.; Carlino, G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Chamizo, M.; Chang, Y.H.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G.M.; Chen, H.F.; Chen, H.S.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; de la Cruz, B.; Cucciarelli, S.; van Dalen, J.A.; de Asmundis, R.; Deglon, P.; Debreczeni, J.; Degre, A.; Dehmelt, K.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; Dionisi, C.; Dittmar, M.; Doria, A.; Dova, M.T.; Duchesneau, D.; Duda, M.; Echenard, B.; Eline, A.; El Hage, A.; El Mamouni, H.; Engler, A.; Eppling, F.J.; Extermann, P.; Falagan, M.A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Fesefeldt, H.; Fiandrini, E.; Field, J.H.; Filthaut, F.; Fisher, P.H.; Fisher, W.; Fisk, I.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Iouri; Ganguli, S.N.; Garcia-Abia, Pablo; Gataullin, M.; Gentile, S.; Giagu, S.; Gong, Z.F.; Grenier, Gerald Jean; Grimm, O.; Gruenewald, M.W.; Guida, M.; van Gulik, R.; Gupta, V.K.; Gurtu, A.; Gutay, L.J.; Haas, D.; Hatzifotiadou, D.; Hebbeker, T.; Herve, Alain; Hirschfelder, J.; Hofer, H.; Hohlmann, M.; Holzner, G.; Hou, S.R.; Hu, Y.; Jin, B.N.; Jones, Lawrence W.; de Jong, P.; Josa-Mutuberria, I.; Kafer, D.; Kaur, M.; Kienzle-Focacci, M.N.; Kim, J.K.; Kirkby, Jasper; Kittel, W.; Klimentov, A.; Konig, A.C.; Kopal, M.; Koutsenko, V.; Kraber, M.; Kraemer, R.W.; Kruger, A.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Le Goff, J.M.; Leiste, R.; Levtchenko, M.; Levtchenko, P.; Li, C.; Likhoded, S.; Lin, C.H.; Lin, W.T.; Linde, F.L.; Lista, L.; Liu, Z.A.; Lohmann, W.; Longo, E.; Lu, Y.S.; Luci, C.; Luminari, L.; Lustermann, W.; Ma, W.G.; Malgeri, L.; Malinin, A.; Mana, C.; Mans, J.; Martin, J.P.; Marzano, F.; Mazumdar, K.; McNeil, R.R.; Mele, S.; Merola, L.; Meschini, M.; Metzger, W.J.; Mihul, A.; Milcent, H.; Mirabelli, G.; Mnich, J.; Mohanty, G.B.; Muanza, G.S.; Muijs, A.J.M.; Musicar, B.; Musy, M.; Nagy, S.; Natale, S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak, T.; Kluge, Hannelies; Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci, P.; Paramatti, R.; Passaleva, G.; Patricelli, S.; Paul, Thomas Cantzon; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.; Pierella, F.; Pioppi, M.; Piroue, P.A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofev, D.; Quartieri, J.; Rahal-Callot, G.; Rahaman, Mohammad Azizur; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P.G.; Ranieri, R.; Raspereza, A.; Razis, P.; Ren, D.; Rescigno, M.; Reucroft, S.; Riemann, S.; Riles, Keith; Roe, B.P.; Romero, L.; Rosca, A.; Rosier-Lees, S.; Roth, Stefan; Rosenbleck, C.; Rubio, J.A.; Ruggiero, G.; Rykaczewski, H.; Sakharov, A.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Schafer, C.; Schegelsky, V.; Schopper, H.; Schotanus, D.J.; Sciacca, C.; Servoli, L.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.; Steuer, M.; Stickland, D.P.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sultanov, G.; Sun, L.Z.; Sushkov, S.; Suter, H.; Swain, J.D.; Szillasi, Z.; Tang, X.W.; Tarjan, P.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, Charles; Ting, Samuel C.C.; Ting, S.M.; Tonwar, S.C.; Toth, J.; Tully, C.; Tung, K.L.; Ulbricht, J.; Valente, E.; Van de Walle, R.T.; Vasquez, R.; Veszpremi, V.; Vesztergombi, G.; Vetlitsky, I.; Vicinanza, D.; Viertel, G.; Villa, S.; Vivargent, M.; Vlachos, S.; Vodopianov, I.; Vogel, H.; Vogt, H.; Vorobev, I.; Vorobyov, A.A.; Wadhwa, M.; Wang, Q.; Wang, X.L.; Wang, Z.M.; Weber, M.; Wienemann, P.; Wilkens, H.; Wynhoff, S.; Xia, L.; Xu, Z.Z.; Yamamoto, J.; Yang, B.Z.; Yang, C.G.; Yang, H.J.; Yang, M.; Yeh, S.C.; Zalite, An.; Zalite, Yu.; Zhang, Z.P.; Zhao, J.; Zhu, G.Y.; Zhu, R.Y.; Zhuang, H.L.; Zichichi, A.; Zimmermann, B.; Zoller, M.

    2003-01-01

    Exclusive rho rho production in two-photon collisions involving a single highly virtual photon is studied with data collected at LEP at centre-of-mass energies 89GeV rho rho is determined as a function of the photon virtuality, Q^2 and the two-photon centre-of-mass energy, Wgg, in the kinematic region: 1.2GeV^2 < Q^2 < 30GeV^2 and 1.1GeV < Wgg < 3GeV.

  11. The ratio Rdp of the quasi-elastic nd → p(nn) to the elastic np → pn charge-exchange process yields at 0 deg over 0.55-2.0 GeV neutron beam energy region: 2. Comparison of the results with the model dependent calculations

    International Nuclear Information System (INIS)

    Sharov, V.I.; Morozov, A.A.; Shindin, R.A.; Chernykh, E.V.; Nomofilov, A.A.; Strunov, L.N.

    2008-01-01

    In our previous paper, the new experimental results on ratio R dp of the quasi-elastic charge-exchange yield at 0 Lab d eg for the nd → p + (nn) reaction to the elastic np → pn charge-exchange yield, were presented. The measurements were carried out at the Nuclotron of the Veksler and Baldin Laboratory of High Energies of the Joint Institute for Nuclear Research at the neutron beam kinetic energies of 0.55, 0.8, 1.0,1.2, 1.4, 1.8 and 2.0 GeV. In this paper, the comparison of these R dp data with the R dp calculations obtained within the impulse approximation by using the invariant amplitude sets from the GW/VPI phase-shift analysis, is made. The calculated R dp values with the set of invariant amplitude data for the elastic np → pn charge exchange at θ p,CM = 0 deg are in a good agreement with the experimental data. It has been confirmed that at θ p,CM = 0 deg the nd → pnn process is caused by the elastic np → pn charge-exchange reaction. Thus, it has been shown that the obtained experimental R dp results can be used for the Delta-Sigma experimental programme to reduce the total ambiguity in the extraction of the amplitude parts

  12. Photo- and electro-production of kaons from nucleon and deuteron; Photo- et electro-production de kaons sur le nucleon et le deuton

    Energy Technology Data Exchange (ETDEWEB)

    Oswald, P

    2001-11-01

    A formalism, based on an effective Lagrangian approach using Feynman diagrammatic techniques in tree approximation, which includes the nucleonic, hyperonic and kaonic resonances, is developed for the following reactions: {gamma}p {yields} K{sup +}{lambda}, K{sup +}{sigma}{sup 0}, K{sup 0}{sigma}{sup +}, K{sup +}{lambda}{sup *}(1405); {gamma}n {yields} K{sup +}{sigma}{sup -}; d({gamma}, K{sup +})X. The formalism is extended to the associated strangeness electroproduction for the same processes. This approach incorporates also the crossing symmetry channels K{sup -}p {yields} {gamma}{lambda},{gamma}{sigma}{sup 0}. Our formalism embodies the off-shell effects inherent to the fermions with spin {>=} 3/2, various hadron electromagnetic form factors, as well as form factors at strong vertices preserving the gauge invariance. The free parameters of the built models are extracted by fitting procedures applied to the available data bases for the elementary processes. All the relevant data are well reproduced with rather simple models. The role played by different ingredients of the models in the reactions mechanisms are thoroughly studied. The sensitivity to the phenomenological models ingredients of different reactions and/or observables with respect to the underlying reaction mechanisms is singled out and suggestions for further experimental and theoretical investigations are emphasized. (author)

  13. Single and double polarization asymmetries from deeply virtual exclusive pi^0 electroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Andrey [University of Connecticut, Storrs, CT; Avakian, Harut A. [Jefferson Lab, Newport News, VA; Burkert, Volker D. [Jefferson Lab, Newport News, VA

    2014-10-01

    The target and double spin asymmetry measurements of exclusive p0 electroproduction were performed for the first time in DIS region at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS) and longitudinally polarized proton target. The wide kinematic coverage and good resolution of CLAS allowed measurements in full azimuthal range providing an opportunity to extract single and double spin asymmetries proportional to polarized structure functions. Their angular dependencies in hadronic center-of-mass system were analyzed, and extracted moments are compared to recent theoretical handbag-based calculations based on chiral-even and chiral-odd GPDs contributions. The interpretation of present results within the framework of the modified perturbative approach and their use as a constraint for models of the t behavior will be discussed.

  14. Pion structure function from leading neutron electroproduction and SU(2) flavor asymmetry

    Energy Technology Data Exchange (ETDEWEB)

    McKenney, Joshua R. [North Carolina State Univ., Raleigh, NC (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Univ. of North Carolina, Chapel Hill, NC (United States); Sato Gonzalez, Nobuo; Melnitchouk, Wally [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Ji, Chueng-Ryong [North Carolina State Univ., Raleigh, NC (United States)

    2016-03-01

    We examine the efficacy of pion exchange models to simultaneously describe leading neutron electroproduction at HERA and the $\\bar{d}-\\bar{u}$ flavor asymmetry in the proton. A detailed $\\chi^2$ analysis of the ZEUS and H1 cross sections, when combined with constraints on the pion flux from Drell-Yan data, allows regions of applicability of one-pion exchange to be delineated. The analysis disfavors several models of the pion flux used in the literature, and yields an improved extraction of the pion structure function and its uncertainties at parton momentum fractions in the pion of $4 \\times 10^{-4} \\lesssim x_\\pi \\lesssim 0.05$ at a scale of $Q^2$=10 GeV$^2$. Based on the fit results, we provide estimates for leading proton structure functions in upcoming tagged deep-inelastic scattering experiments at Jefferson Lab on the deuteron with forward protons.

  15. Transverse-target-spin asymmetry in exclusive $\\omega$-meson electroproduction

    CERN Document Server

    Airapetian, A.; Akopov, Z.; Aschenauer, E.C.; Augustyniak, W.; Avetissian, A.; Belostotski, S.; Blok, H.P.; Borissov, A.; Bryzgalov, V.; Capitani, G.P.; Ciullo, G.; Contalbrigo, M.; Dalpiaz, P.F.; Deconinck, W.; De Leo, R.; De Sanctis, E.; Diefenthaler, M.; Di Nezza, P.; Düren, M.; Elbakian, G.; Ellinghaus, F.; Felawka, L.; Frullani, S.; Gabbert, D.; Gapienko, G.; Gapienko, V.; Gharibyan, V.; Giordano, F.; Gliske, S.; Hasch, D.; Hoek, M.; Holler, Y.; Ivanilov, A.; Jackson, H.E.; Joosten, S.; Kaiser, R.; Karyan, G.; Keri, T.; Kinney, E.; Kisselev, A.; Korotkov, V.; Kozlov, V.; Krivokhijine, V.G.; Lagamba, L.; Lapikás, L.; Lehmann, I.; Lenisa, P.; Lorenzon, W.; Ma, B.Q.; Manaenkov, S.I.; Mao, Y.; Marianski, B.; Marukyan, H.; Miyachi, Y.; Movsisyan, A.; Muccifora, V.; Naryshkin, Y.; Nass, A.; Negodaev, M.; Nowak, W.D.; Pappalardo, L.L.; Perez-Benito, R.; Petrosyan, A.; Reimer, P.E.; Reolon, A.R.; Riedl, C.; Rith, K.; Rosner, G.; Rostomyan, A.; Rubin, J.; Ryckbosch, D.; Salomatin, Y.; Schnell, G.; Seitz, B.; Shibata, T.A.; Statera, M.; Steffens, E.; Steijger, J.J.M.; Stinzing, F.; Taroian, S.; Terkulov, A.; Truty, R.; Trzcinski, A.; Tytgat, M.; Van Haarlem, Y.; Van Hulse, C.; Vikhrov, V.; Vilardi, I.; Vogel, C.; Wang, S.; Yaschenko, S.; Yen, S.; Zihlmann, B.; Zupranski, P.

    2015-12-17

    Hard exclusive electroproduction of $\\omega$ mesons is studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. The amplitudes of five azimuthal modulations of the single-spin asymmetry of the cross section with respect to the transverse proton polarization are measured. They are determined in the entire kinematic region as well as for two bins in photon virtuality and momentum transfer to the nucleon. Also, a separation of asymmetry amplitudes into longitudinal and transverse components is done. These results are compared to a phenomenological model that includes the pion pole contribution. Within this model, the data favor a positive $\\pi\\omega$ transition form factor.

  16. Transverse target single-spin asymmetry in inclusive electroproduction of charged pions and kaons

    Energy Technology Data Exchange (ETDEWEB)

    Airapetian, A. [Giessen Univ. (Germany). 2. Physikalisches Inst.; Michigan Univ., Ann Arbor, MI (United States). Randall Laboratory of Physics; Akopov, N. [Yerevan Physics Institute (Argentina); Akopov, Z. [DESY Hamburg (Germany)] [and others; Collaboration: HERMES Collaboration

    2013-10-15

    Single-spin asymmetries were investigated in inclusive electroproduction of charged pions and kaons from transversely polarized protons at the HERMES experiment. The asymmetries were studied as a function of the azimuthal angle {psi} about the beam direction between the target-spin direction and the hadron production plane, the transverse hadron momentum P{sub T} relative to the direction of the incident beam, and the Feynman variable x{sub F}. The sin {psi} amplitudes are positive for {pi}{sup +} and K{sup +}, slightly negative for {pi}{sup -} consistent with zero for K{sup -}, with particular P{sub T} but weak x{sub F} dependences. Especially large asymmetries are observed for two small subsamples of events, where also the scattered electron was recorded by the spectrometer.

  17. Transverse-target-spin asymmetry in exclusive ω-meson electroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Airapetian, A. [Justus-Liebig Universitaet Giessen, II. Physikalisches Institut, Giessen (Germany); University of Michigan, Randall Laboratory of Physics, Ann Arbor, MI (United States); Akopov, N.; Avetissian, A.; Elbakian, G.; Gharibyan, V.; Karyan, G.; Marukyan, H.; Petrosyan, A.; Taroian, S. [Yerevan Physics Institute, Yerevan (Armenia); Akopov, Z.; Borissov, A.; Deconinck, W.; Holler, Y.; Rostomyan, A.; Zihlmann, B. [DESY, Hamburg (Germany); Aschenauer, E.C.; Gabbert, D.; Negodaev, M.; Nowak, W.D. [DESY, Zeuthen (Germany); Augustyniak, W.; Marianski, B.; Trzcinski, A.; Zupranski, P. [National Centre for Nuclear Research, Warsaw (Poland); Belostotski, S.; Kisselev, A.; Manaenkov, S.I.; Naryshkin, Y.; Vikhrov, V. [B.P. Konstantinov Petersburg Nuclear Physics Institute, Leningrad Region (Russian Federation); Blok, H.P. [National Institute for Subatomic Physics (Nikhef), Amsterdam (Netherlands); VU University, Department of Physics and Astronomy, Amsterdam (Netherlands); Bryzgalov, V.; Gapienko, G.; Gapienko, V.; Ivanilov, A.; Korotkov, V.; Salomatin, Y. [Institute for High Energy Physics, Moscow Region (Russian Federation); Capitani, G.P.; De Sanctis, E.; Di Nezza, P.; Hasch, D.; Muccifora, V.; Reolon, A.R. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati, Frascati (Italy); Ciullo, G.; Dalpiaz, P.F.; Lenisa, P.; Pappalardo, L.L.; Statera, M. [Istituto Nazionale di Fisica Nucleare, Sezione di Ferrara, Ferrara (Italy); Universita di Ferrara, Dipartimento di Fisica e Scienze della Terra, Ferrara (Italy); Contalbrigo, M. [Istituto Nazionale di Fisica Nucleare, Sezione di Ferrara, Ferrara (Italy); De Leo, R.; Lagamba, L.; Vilardi, I. [Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Bari (Italy); Diefenthaler, M. [Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erlangen (Germany); University of Illinois, Department of Physics, Urbana, IL (United States); Dueren, M.; Keri, T.; Perez-Benito, R. [Justus-Liebig Universitaet Giessen, II. Physikalisches Institut, Giessen (Germany); Ellinghaus, F.; Kinney, E. [University of Colorado, Nuclear Physics Laboratory, Boulder, CO (United States); Felawka, L.; Yen, S. [Vancouver, TRIUMF, BC (Canada); Frullani, S. [Istituto Nazionale di Fisica Nucleare, Gruppo Collegato Sanita, Sezione di Roma, Rome (Italy); Istituto Superiore di Sanita, Rome (Italy); Giordano, F. [Istituto Nazionale di Fisica Nucleare, Sezione di Ferrara, Ferrara (Italy); Universita di Ferrara, Dipartimento di Fisica e Scienze della Terra, Ferrara (Italy); University of Illinois, Department of Physics, Urbana, IL (United States); Gliske, S.; Lorenzon, W. [University of Michigan, Randall Laboratory of Physics, Ann Arbor, MI (United States); Hoek, M.; Kaiser, R.; Lehmann, I.; Rosner, G.; Seitz, B. [University of Glasgow, SUPA, School of Physics and Astronomy, Glasgow (United Kingdom); Jackson, H.E.; Reimer, P.E. [Argonne National Laboratory, Physics Division, Argonne, IL (United States); Joosten, S.; Ryckbosch, D.; Tytgat, M.; Haarlem, Y. van [Ghent University, Department of Physics and Astronomy, Gent (Belgium); Kozlov, V.; Terkulov, A. [Lebedev Physical Institute, Moscow (Russian Federation); Krivokhijine, V.G. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Lapikas, L.; Steijger, J.J.M. [National Institute for Subatomic Physics (Nikhef), Amsterdam (NL); Ma, B.Q.; Mao, Y.; Wang, S. [Peking University, School of Physics, Beijing (CN); Miyachi, Y.; Shibata, T.A. [Tokyo Institute of Technology, Department of Physics, Tokyo (JP); Movsisyan, A. [Istituto Nazionale di Fisica Nucleare, Sezione di Ferrara, Ferrara (IT); Yerevan Physics Institute, Yerevan (AM); Nass, A.; Rith, K.; Steffens, E.; Stinzing, F.; Vogel, C. [Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erlangen (DE); Riedl, C. [DESY, Zeuthen (DE); University of Illinois, Department of Physics, Urbana, IL (US); Rubin, J. [University of Illinois, Department of Physics, Urbana, IL (US); University of Michigan, Randall Laboratory of Physics, Ann Arbor, MI (US); Schnell, G. [University of the Basque Country UPV/EHU, Department of Theoretical Physics, Bilbao (ES); Basque Foundation for Science, IKERBASQUE, Bilbao (ES); Ghent University, Department of Physics and Astronomy, Gent (BE); Truty, R. [University of Illinois, Department of Physics, Urbana, IL (US); Hulse, C. van [University of the Basque Country UPV/EHU, Department of Theoretical Physics, Bilbao (ES); Ghent University, Department of Physics and Astronomy, Gent (BE); Yaschenko, S. [DESY, Hamburg (DE); Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erlangen (DE); Collaboration: The HERMES Collaboration

    2015-12-15

    Hard exclusive electroproduction of ω mesons is studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. The amplitudes of five azimuthal modulations of the single-spin asymmetry of the cross section with respect to the transverse proton polarization are measured. They are determined in the entire kinematic region as well as for two bins in photon virtuality and momentum transfer to the nucleon. Also, a separation of asymmetry amplitudes into longitudinal and transverse components is done. These results are compared to a phenomenological model that includes the pion pole contribution. Within this model, the data favor a positive πω transition form factor. (orig.)

  18. Electroproduction of ηmesons at the proton near the N(1535) S11 resonance

    International Nuclear Information System (INIS)

    Wilhelm, M.

    1993-06-01

    The η electroproduction on liquid hydrogen has been measured at the accelerator facility ELSA in Bonn near the N(1535)S 11 resonance at an average four momentum transfer q 2 =-0.056(GeV/c) 2 . The beam energy was chosen to 1600 MeV and the scattered electron was detected in a magnetic spectrometer at an angle of 12 . In addition, the two photons from the η decay were measured in two arrays of 88 lead glass counters each. The total cross section of the η production is predominated by the coupling of the N(1535)S 11 resonance to the η meson. The extracted angular distributions show clearly contributions from higher partial waves. (orig.)

  19. Exclusive η electroproduction at W >2 GeV with CLAS and transversity generalized parton distributions

    Science.gov (United States)

    Bedlinskiy, I.; Kubarovsky, V.; Stoler, P.; Adhikari, K. P.; Akbar, Z.; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.; Burkert, V. D.; Cao, T.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Ciullo, G.; Clark, L.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dupre, R.; Alaoui, A. El; Fassi, L. El; Elouadrhiri, L.; Eugenio, P.; Fanchini, E.; Fedotov, G.; Fersch, R.; Filippi, A.; Fleming, J. A.; Forest, T. A.; Garçon, M.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gleason, C.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Harrison, N.; Hattawy, M.; Hicks, K.; Hughes, S. M.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Joosten, S.; Keller, D.; Khachatryan, G.; Khachatryan, M.; Khandaker, M.; Kim, A.; Kim, W.; Klein, F. J.; Kuhn, S. E.; Kuleshov, S. V.; Lanza, L.; Lenisa, P.; Livingston, K.; MacGregor, I. J. D.; Markov, N.; McKinnon, B.; Meziani, Z. E.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Movsisyan, A.; Munoz Camacho, C.; Nadel-Turonski, P.; Net, L. A.; Ni, A.; Niccolai, S.; Niculescu, G.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Peng, P.; Phelps, W.; Pisano, S.; Pogorelko, O.; Price, J. W.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Saini, M. S.; Salgado, C.; Schumacher, R. A.; Sharabian, Y. G.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Tian, Ye; Torayev, B.; Turisini, M.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Yurov, M.; Zachariou, N.; Zhang, J.; Zonta, I.; CLAS Collaboration

    2017-03-01

    The cross section of the exclusive η electroproduction reaction e p →e'p'η was measured at Jefferson Laboratory with a 5.75 GeV electron beam and the CLAS detector. Differential cross sections d4σ /d t d Q2d xBd ϕη and structure functions σU=σT+ɛ σL,σT T , and σL T, as functions of t , were obtained over a wide range of Q2 and xB. The η structure functions are compared with those previously measured for π0 at the same kinematics. At low t , both π0 and η are described reasonably well by generalized parton distributions (GPDs) in which chiral-odd transversity GPDs are dominant. The π0 and η data, when taken together, can facilitate the flavor decomposition of the transversity GPDs.

  20. Low momentum transfer measurements of pion electroproduction and virtual Compton scattering at the Delta resonance

    Energy Technology Data Exchange (ETDEWEB)

    Blomberg, Adam [Temple Univ., Philadelphia, PA (United States)

    2016-12-01

    Non-spherical components of the nucleon wave function are measured through p(e,e'p)π0 experiment at the Δ+(1232) resonance for Q2 = 0.04, 0.09, and 0.13 (GeV=c)2 utilizing the Jefferson National Accelerator Facility (JLab) pulsed beam and Hall A spectrometers. The new data extend the measurements of the Coulomb quadrupole amplitude to the lowest momentum transfer ever reached. The results disagree with predictions of constituent quark models and are in reasonable agreement with dynamical calculations that include pion cloud effects, chiral effective field theory and lattice calculations. The reported measurements indicate that improvement is required to the theoretical calculations and provide valuable input that will allow their refinements. The Coulomb to magnetic multipole ratio (CMR) and generalized polarizability (GP) of the nucleon are also measured through virtual Compton scattering (VCS) for Q2 = 0.2(GeV=c)2 utilizing the Mainz Microtron (MAMI) continuous beam and A1 spectrometers. This data represents the first low Q2 GP measurement at the Δ+(1232) resonance. The GP measurement explores a region where previous data and theoretical calculations disagree. The CMR measurement will be the first VCS extraction to compare with world data generated through pion electroproduction. The Dispersion Relation (DR) model used for the VCS extraction provides a new theoretical framework for the data signal and backgrounds that is largely independent from the pion electroproduction models. The independence of the DR from the traditional models provides a strong crosscheck on the ability of the models to isolate the data signal.

  1. Direct compatibility check of the CEA and Cornell electroproduction pion form factor data with e+e- ones

    International Nuclear Information System (INIS)

    Dubnicka, S.; Martinovic, L.

    1988-01-01

    Using precise experimental information on the imaginary part of the pion form factor from e + e - → π + π - up to the inelastic threshold and QCD constraints for it in the range of momenta (m π 0 +m ω ) 2 < t < infinity, was investigated by means of a dispersion integral the reliability of individual electroproduction CEA and Cornell model-dependent pion form factor data points

  2. Kaon electroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Markowitz, P. [Univ. of Maryland, College Park (United States)

    1994-04-01

    The talk will focus on the physics which can be addressed by looking at semi-inclusive and exclusive channels in the DIS region. In particular, the author examines how this physics is reflected in the separated response functions.

  3. Kaon electroproduction

    International Nuclear Information System (INIS)

    Markowitz, P.

    1994-01-01

    The talk will focus on the physics which can be addressed by looking at semi-inclusive and exclusive channels in the DIS region. In particular, the author examines how this physics is reflected in the separated response functions

  4. Precision Measurement of Electroproduction of pi0 near Threshold

    Energy Technology Data Exchange (ETDEWEB)

    Chirapatpimol, Khem [Chiang Mai Univ. (Thailand)

    2012-05-01

    Electromagnetic production of neutral pions near threshold is the most basic, lowest energy reaction in which a new hadron is created. The electromagnetic interaction is well understood so measurements of this reaction can yield direct insight into the hadronic production mechanism. During the past three decades there have been many developments in both the measurement and theory of threshold pion production, starting with measurements of photo-production at Saclay in 1986 and at Mainz in 1990. These measurements indicated a surprising discrepancy with so-called Low Energy Theorems (LETs) which are based on quite fundamental symmetries and considerations. Chiral Perturbation Theory (ChPT) is an effective field theoretic description of the nuclear force which contains the underlying symmetries of the force but deals with nucleons and pions rather than quarks and gluons. It has the advantage of being applicable at low energies but requires tuning some parameters to experimental data. Once these parameters have been determined ChPT predicts how the reaction should behave as a function of the kinematic variable. When applied to the reaction, p(γ,π0)p, near threshold it explained the discrepancy with the LETs and made predictions for electroproduction, p(e,e'p)π 0. Electroproduction measurements at Mainz in the 1990's showed a clear discrepancy with these predictions of ChPT; with parameters determined from one set of kinematics the data for a second set lay far from the predicted value. However, recently completed measurements at Mainz disagreed with their previous measurements. In the experiment presented here, measurements of neutral pion electroproduction,p(e,e'p)π0, were made in bins of momentum transfer, Q2, between Q2 = 0.05 [GeV/c]2 and Q2 = 0.15 [GeV/c]0 and of center-of-mass energy, W, between 0 ≤ W ≤ 30 MeV (above threshold). The experiment was

  5. Quasi-elastic shadowing in nucleus-nucleus elastic scattering

    Energy Technology Data Exchange (ETDEWEB)

    Dymarz, R; Malecki, A [Institute of Nuclear Physics, Krakow (Poland); Gluski, K [Institute of Nuclear Research, Warsaw (Poland); Picchi, P [Turin Univ. (Italy). Ist. di Fisica; Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica)

    1979-01-06

    The complete evaluation of the Glauber multiple-scattering series for nucleus-nucleus collisions is a very difficult task and that is why various approximate formulae were proposed. In this work some of these approximations are discussed.

  6. Fusion and quasi-elastic processes near the Coulomb barrier

    International Nuclear Information System (INIS)

    Abriola, D.

    1987-01-01

    An overview of the fusion phenomenon below Coulomb barrier is presented. The current theoretical descriptions, emphasizing the relations with direct reactions are discussed. The definition and systematic behaviour of the fusion enhancement below the Coulomb barrier are also presented. The role of coupling to surface degrees of freedom, namely permanent deformations of nuclei, inelastic and transfer channels is shown. The importance of studies describing simultaneously quase-elastic processes and fusion are also shown. (M.C.K.) [pt

  7. Quenching and hardening in the transverse quasi-elastic peak

    International Nuclear Information System (INIS)

    Alberico, W.M.; Molinari, A.; Ericson, M.

    1981-09-01

    We study in the RPA framework the response of symmetric, infinite nuclear matter to a spin-isospin sensitive probe with both σ.q and σ.xq couplings. The two responses, similar in the low-q region, differ markedly for moderate momenta (>=1fm -1 ). Indeed, whereas the longitudinal one displays a softening and an enhancement (due to the attractive character of the associated particle-hole force), the transverse response is quenched and hardened with respect to the free Fermi gas. The existing experimental data, which we analyze, are compatible with our results. We also explore the total strengths and find that for repulsive forces they are appreciably reduced by the RPA correlations. Large part of this quenching comes from the Δ excitation (LLEE effect), but some reduction is still present even when the nucleonic degrees of freedom are neglected. This illustrates a violation of strength conservation brougth about by the RPA correlations in the spin-isospin channel

  8. The pseudo-scalar form factor of the nucleon, the sigma-like term, and the L0+ amplitude for charged pion electro-production near threshold

    International Nuclear Information System (INIS)

    Cheoun, Myung Ki; Kim, K.S.

    2007-01-01

    The pseudo-scalar form factor, which represents the pseudo-scalar quark density distribution due to finite quark masses on the nucleon, is shown to manifest itself with the induced pseudo-scalar form factor in the L 0 + amplitude for the charged pion electro-production. Both form factors show their own peculiar momentum dependence. Under the approximation on which the Goldberger-Treiman relation holds, a sum of both form factors' contributions accounts for the t-channel contribution in the charged pion electro-production near threshold

  9. Variable-flavor-number scheme in analysis of heavy-quark electro-production data

    International Nuclear Information System (INIS)

    Alekhin, S.; Bluemlein, J.; Klein, S.; Moch, S.

    2009-08-01

    We check the impact of the factorization scheme employed in the calculation of the heavy-quark deep-inelastic scattering (DIS) electro-production on the PDFs determined in the NNLO QCD analysis of the world inclusive neutral-current DIS data combined with the ones on the neutrino-nucleon DIS di-muon production and the fixed-target Drell-Yan process. The charm-quark DIS contribution is calculated in the general-mass variable-flavor-number (GMVFN) scheme: At asymptotically large values of the momentum transfer Q it is given by the zero-mass 4-flavor scheme and at the value of Q equal to the charm-quark mass it is smoothly matched with the 3-flavor scheme using the Buza-Matiounine-Smith-van Neerven prescription. The PDFs obtained in this variant of the fit are very similar to the ones obtained in the fit with a 3-flavor scheme employed. Our 5-flavor PDFs derived from the 3-flavor ones using the NNLO matching conditions are used to calculate the rates of W ± /Z and t anti t production at the Tevatron collider and the LHC at NNLO. (orig.)

  10. Semi-Inclusive Single Pion Electroproduction From Deuteron and Proton Targets

    Energy Technology Data Exchange (ETDEWEB)

    Kalantarians, Narbe [Univ. of Houston, TX (United States)

    2008-08-01

    Semi-inclusive electroproduction of all three pion flavors (π+, π-0) from both deuteron and proton targets is measured for Q^2 > 1.1 GeV2, 0.12 < x < 0.48, 0.3 < z < 0.7. and Mx > 1.4 GeV. We study the PT, Z, and Φh dependences for the ratio of yields d(e,e',π)X/p(e,e'π)X. From these ratios it is possible to study the d/u valence quark distributions for the neutron and proton as well as the ratio of (current) fragmentation functions D-/D+. The data presented is from Jefferson Lab experiment PR94-102, using an electron beam with energy 5.769 GeV with beam current of 7nA. The results agree with previous data as well as provide an extended kinematic coverage.

  11. Measurement of unpolarized semi-inclusive pi+ electroproduction off the proton

    Energy Technology Data Exchange (ETDEWEB)

    Osipenko, Mikhail; Ripani, Marco; Ricco, Giovanni; Avagyan, Harutyun; De Vita, Raffaella; Adams, Gary; Amaryan, Moscov; Amaryan, Moskov; Ambrozewicz, Pawel; Anghinolfi, Marco; Asryan, Gegham; Audit, Gerard; Bagdasaryan, H.; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Baltzell, Nathan; Barrow, Steve; Battaglieri, Marco; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bonner, Billy; Bouchigny, Sylvain; Boyarinov, Sergey; Bradford, Robert; Branford, Derek; Briscoe, Wilbert; Brooks, William; Bultmann, S.; Bueltmann, Stephen; Burkert, Volker; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Cazes, Antoine; Ceccopieri, Federico; Chen, Shifeng; Cole, Philip; Collins, Patrick; Coltharp, Philip; Corvisiero, Pietro; Crabb, Donald; Crede, Volker; Cummings, John; Dashyan, Natalya; De Masi, Rita; De Sanctis, Enzo; Degtiarenko, Pavel; Denizli, Haluk; Dennis, Lawrence; Deur, Alexandre; Dharmawardane, Kahanawita; Dhuga, Kalvir; Dickson, Richard; Djalali, Chaden; Dodge, Gail; Donnelly, J.; Doughty, David; Drozdov, V.; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fatemi, Renee; Fedotov, Gleb; Feldman, Gerald; Feuerbach, Robert; Funsten, Herbert; Garcon, Michel; Gavalian, Gagik; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Golovach, Evgeny; Gonenc, Atilla; Gordon, Christopher; Gothe, Ralf; Griffioen, Keith; Guidal, Michel; Guillo, Matthieu; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hadjidakis, Cynthia; Hafidi, Kawtar; Hakobyan, Hayk; Hakobyan, Rafael; Hanretty, Charles; Hardie, John; Hassall, Neil; Heddle, David; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ilyichev, Alexander; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Kellie, James; Khandaker, Mahbubul; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Klimenko, Alexei; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, David; Li, Ji; Livingston, Kenneth; Lu, Haiyun; MacCormick, Marion; Marchand, Claude; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McCracken, Michael; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mehrabyan, Surik; Melone, Joseph; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Morand, Ludyvine; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Napolitano, James; Nasseripour, Rakhsha; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; O' Rielly, Grant; Ostrovidov, Alexander; Park, Kijun; Pasyuk, Evgueni; Paterson, Craig; Pereira, Sergio; Philips, Sasha; Pierce, Joshua; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Polli, Ermanno; Popa, Iulian; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Prok, Yelena; Protopopescu, Dan; Qin, Liming; Raue, Brian; Riccardi, Gregory; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Rubin, Philip; Sabatie, Franck; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Shvedunov, Nikolay; Skabelin, Alexander; Smith, Elton; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinskiy, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Tedeschi, David; Thoma, Ulrike; Tkabladze, Avtandil; Tkachenko, Svyatoslav; Todor, Luminita; Trentadue, L.; Tur, Clarisse; Ungaro, Maurizio; Vineyard, Michael; Vlassov, Alexander; Watts, Daniel; Weinstein, Lawrence; Weygand, Dennis; Williams,

    2008-01-01

    Semi-inclusive pi+ electroproduction on protons has been measured with the CLAS detector at Jefferson Lab. The measurement was performed on a liquid-hydrogen target using a 5.75 GeV electron beam. The complete five-fold differential cross sections were measured over a wide kinematic range in Q2, x, z, and pT and over the complete range of azimuthal angles, phi, enabling us to separate the different structure functions, H2+eps*H1, H3 and H4. Our measurements of H2 at low-x were found to be in fairly good agreement with pQCD calculations, suggesting a precocious factorization of the process. Indeed, the conventional f(x)*D(z) term can account for almost all of the observed cross section, even at small z. The measured xF-distributions are in qualitative agreement with high energy data, which suggests a surprising numerical similarity between the spectator diquark fragmentation in the present reaction and the anti-quark fragmentation measured in e+e- collisions. We have observed that the p

  12. Electroproduction of $\\phi(1020)$ Mesons at High $Q^2$ with CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Santoro, Joseph; Smith, Elton; Garcon, Michel; Guidal, Michel; Laget, Jean; Weiss, Christian; Adams, Gary; Amaryan, Moscov; Amaryan, Moskov; Anghinolfi, Marco; Asryan, Gegham; Audit, Gerard; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Ball, J.P.; Ball, Jacques; Ball, James; Baltzell, Nathan; Barrow, Steve; Battaglieri, Marco; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bonner, Billy; Bookwalter, Craig; Bouchigny, Sylvain; Bouchigny, Sylvain; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Bultmann, S.; Bueltmann, Stephen; Bultmann, S.; Bueltmann, Stephen; Burkert, Volker; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Casey, Liam; Cazes, Antoine; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Cords, Dieter; Corvisiero, Pietro; Crabb, Donald; Crannell, Hall; Crede, Volker; Cummings, John; Dale, Daniel; Dashyan, Natalya; De Masi, Rita; De Sanctis, Enzo; De Vita, Raffaella; Degtiarenko, Pavel; Denizli, Haluk; Dennis, Lawrence; Deur, Alexandre; Dhamija, Seema; Dharmawardane, Kahanawita; Dhuga, Kalvir; Dickson, Richard; Djalali, Chaden; Dodge, Gail; Doughty, David; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fatemi, Renee; Fedotov, Gleb; Feuerbach, Robert; Ficenec, John; Forest, Tony; Fradi, Ahmed; Funsten, Herbert; Gavalian, Gagik; Gevorgyan, Nerses; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gohn, Wesley; Gordon, Christopher; Gothe, Ralf; Graham, Lewis; Griffioen, Keith; Guillo, Matthieu; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hadjidakis, Cynthia; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Hardie, John; Hassall, Neil; Heddle, David; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Keller, Dustin; Kellie, James; Khandaker, Mahbubul; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Klimenko, Alexei; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Kuznetsov, Viacheslav; Lachniet, Jeff; Langheinrich, Jorn; Lawrence, David; Livingston, Kenneth; Lu, Haiyun; MacCormick, Marion; Marchand, Claude; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mehrabyan, Surik; Melone, Joseph; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Morand, Ludyvine; Moreno, Brahim; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Nasseripour, Rakhsha; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; O' Rielly, Grant; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kijun; Park, Sungkyun; Pasyuk, Evgueni; Paterson, Craig; Pereira, Sergio; Philips, Sasha; Pierce, Joshua; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Popa, Iulian; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Procureur, Sebastien; Prok, Yelena; Protopopescu, Dan; Qin, Liming; Raue, Brian; Riccardi, Gregory; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Sabatie, Franck; Saini, Mukesh; Salamanca, Julian; Salgado, Carlos; Sapunenko, Vladimir; Schott, Diane; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shvedunov, Nikolay; Skabelin, Alexander; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinsky, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Tedeschi, David; Tkabladze, A

    2008-08-01

    http://dx.doi.org/10.1103/PhysRevC.78.025210
    Electroproduction of exclusive $\\phi$ vector mesons has been studied with the CLAS detector in the kinematical range $1.6\\leq Q^2\\leq 3.8$ GeV$^{2}$, $0.0\\leq t^{\\prime}\\leq 3.6$ GeV$^{2}$, and $2.0\\leq W\\leq 3.0$ GeV. The scaling exponent for the total cross section as $1/(Q^2+M_{\\phi}^2)^n$ was determined to be $n=2.49\\pm 0.33$. The slope of the four-momentum transfer $t'$ distribution is $b_{\\phi}=0.98 \\pm 0.17$ GeV$^{-2}$. The data are consistent with the assumption of s-channel helicity conservation (SCHC). Under this assumption, we determine the ratio of longitudinal to transverse cross sections to be $R=0.86 \\pm 0.24$. A 2-gluon exchange model is able to reproduce the main features of the data.

  13. Photo- and electro-production of kaons from nucleon and deuteron

    International Nuclear Information System (INIS)

    Oswald, P.

    2001-11-01

    A formalism, based on an effective Lagrangian approach using Feynman diagrammatic techniques in tree approximation, which includes the nucleonic, hyperonic and kaonic resonances, is developed for the following reactions: γp → K + Λ, K + Σ 0 , K 0 Σ + , K + Λ * (1405); γn → K + Σ - ; d(γ, K + )X. The formalism is extended to the associated strangeness electroproduction for the same processes. This approach incorporates also the crossing symmetry channels K - p → γΛ,γΣ 0 . Our formalism embodies the off-shell effects inherent to the fermions with spin ≥ 3/2, various hadron electromagnetic form factors, as well as form factors at strong vertices preserving the gauge invariance. The free parameters of the built models are extracted by fitting procedures applied to the available data bases for the elementary processes. All the relevant data are well reproduced with rather simple models. The role played by different ingredients of the models in the reactions mechanisms are thoroughly studied. The sensitivity to the phenomenological models ingredients of different reactions and/or observables with respect to the underlying reaction mechanisms is singled out and suggestions for further experimental and theoretical investigations are emphasized. (author)

  14. Ratios of helicity amplitudes for exclusive ρ0 electroproduction on transversely polarized proton

    Directory of Open Access Journals (Sweden)

    Manaenkov Serguei

    2017-01-01

    Full Text Available Exclusive ρ0-meson electroproduction is studied by the HERMES experiment, using the 27.6 GeV longitudinally polarized electron/positron beam of HERA and a transversely polarized hydrogen target, in the kinematic region 1.0 GeV2 < Q2 < 7.0 GeV2, 3.0 GeV < W < 6.3 GeV, and −t′ < 0.4 GeV2. Using an unbinned maximum-likelihood method, 25 parameters are extracted. They determine the real and imaginary parts of the ratios of certain helicity amplitudes describing ρ0-meson production by a virtual photon, where the denominator is the dominant amplitude F012012${F_{0{1 \\over 2}}}_{0{1 \\over 2}}$. The latter is the nucleon-helicity-non-flip amplitude, which describes the production of a longitudinal ρ0 meson by a longitudinal virtual photon. The transverse target polarization allows for the first time the extraction of ratios of a number of nucleon-helicity-flip amplitudes to F012012${F_{0{1 \\over 2}}}_{0{1 \\over 2}}$. The ratios of nucleon-helicity-non-flip amplitudes are found to be in good agreement with those from the previous HERMES analysis.

  15. Deep exclusive {pi}{sup +} electroproduction off the proton at CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kijun; Gothe, Ralf; Guidal, Michel; Laget, Jean; Adhikari, K P; Bennet, R P; Biselli, A S; Chandavar, S; MacGregor, I. J. D; Munoz Camacho, C; Anefalos-Pereira, S; Rimal, D; Tang, W

    2013-01-01

    The exclusive electroproduction of {pi}{sup +} above the resonance region was studied using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Laboratory by scattering a 6 GeV continuous electron beam off a hydrogen target. The large acceptance and good resolution of CLAS, together with the high luminosity, allowed us to measure the cross section for the {gamma}* p {yields} n {pi}{sup +} process in 140 (Q{sup 2}, x{sub B}, t) bins: 0.16

  16. Exclusive π0 electroproduction at W >2 GeV with CLAS

    Science.gov (United States)

    Bedlinskiy, I.; Kubarovsky, V.; Niccolai, S.; Stoler, P.; Adhikari, K. P.; Anderson, M. D.; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Biselli, A. S.; Boiarinov, S.; Bono, J.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Doughty, D.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fleming, J. A.; Forest, T. A.; Garillon, B.; Garçon, M.; Gavalian, G.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guegan, B.; Guo, L.; Hafidi, K.; Hakobyan, H.; Harrison, N.; Hattawy, M.; Hicks, K.; Holtrop, M.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jo, H. S.; Joo, K.; Keller, D.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Koirala, S.; Kuhn, S. E.; Kuleshov, S. V.; Lenisa, P.; Levine, W. I.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; Mayer, M.; McKinnon, B.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Moody, C. I.; Moutarde, H.; Movsisyan, A.; Munoz Camacho, C.; Nadel-Turonski, P.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Pappalardo, L. L.; Park, K.; Park, S.; Pasyuk, E.; Phelps, E.; Phelps, W.; Phillips, J. J.; Pisano, S.; Pogorelko, O.; Price, J. W.; Prok, Y.; Protopopescu, D.; Procureur, S.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Ritchie, B. G.; Rizzo, A.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Senderovich, I.; Sharabian, Y. G.; Simonyan, A.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Stepanyan, S. S.; Strauch, S.; Sytnik, V.; Tang, W.; Tian, Ye; Ungaro, M.; Vlassov, A. V.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D.; Wei, X.; Weinstein, L. B.; Yurov, M.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

    2014-08-01

    Exclusive neutral-pion electroproduction (ep→e'p'π0) was measured at Jefferson Lab with a 5.75-GeV electron beam and the CLAS detector. Differential cross sections d4σ/dtdQ2dxBdϕπ and structure functions σT+ɛσL,σTT, and σLT as functions of t were obtained over a wide range of Q2 and xB. The data are compared with Regge and handbag theoretical calculations. Analyses in both frameworks find that a large dominance of transverse processes is necessary to explain the experimental results. For the Regge analysis it is found that the inclusion of vector meson rescattering processes is necessary to bring the magnitude of the calculated and measured structure functions into rough agreement. In the handbag framework, there are two independent calculations, both of which appear to roughly explain the magnitude of the structure functions in terms of transversity generalized parton distributions.

  17. Exclusive pi^0 electroproduction at W > 2 GeV with CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Bedlinskiy, I; Kubarovsky, V; Niccolai, S; Stoler, P; Adhikari, K P; Anderson, M D; Pereira, S Anefalos; Avakian, H; Ball, J; Baltzell, N A; Battaglieri, M; Batourine, V; Biselli, A S; Boiarinov, S; Bono, J; Briscoe, W J; Brooks, W K; Burkert, V D; Carman, D S; Celentano, A; Chandavar, S; Colaneri, L; Cole, P L; Contalbrigo, M; Cortes, O; Crede, V; D' Angelo, A; Dashyan, N; De Vita, R; De Sanctis, E; Deur, A; Djalali, C; Doughty, D; Dupre, R; Egiyan, H; El Alaoui, A; El Fassi, L; Elouadrhiri, L; Eugenio, P; Fedotov, G; Fegan, S; Fleming, J A; Forest, T A; Garillon, B; Garcon, M; Gavalian, G; Gevorgyan, N; Ghandilyan, Y; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Golovatch, E; Gothe, R W; Griffioen, K A; Guegan, B; Guo, L; Hafidi, K; Hakobyan, H; Harrison, N; Hattawy, M; Hicks, K; Holtrop, M; Ireland, D G; Ishkhanov, B S; Isupov, E L; Jenkins, D; Jo, H S; Joo, K; Keller, D; Khandaker, M; Kim, A; Kim, W; Klein, A; Klein, F J; Koirala, S; Kuhn, S E; Kuleshov, S V; Lenisa, P; Levine, W I; Livingston, K; Lu, H Y; MacGregor, I J.D.; Markov, N; Mayer, M; McKinnon, B; Mirazita, M; Mokeev, V; Montgomery, R A; Moody, C I; Moutarde, H; Movsisyan, A; Munoz Camacho, C; Nadel-Turonski, P; Niculescu, I; Osipenko, M; Ostrovidov, A I; Pappalardo, L L; Park, K; Park, S; Pasyuk, E; Phelps, E; Phelps, W; Phillips, J J; Pisano, S; Pogorelko, O; Price, J W; Prok, Y; Protopopescu, D; Procureur, S; Puckett, A J.R.; Raue, B A; Ripani, M; Ritchie, B G; Rizzo, A; Rossi, P; Roy, P; Sabatié, F; Salgado, C; Schott, D; Schumacher, R A; Seder, E; Senderovich, I; Sharabian, Y G; Simonyan, A; Smith, G D; Sober, D I; Sokhan, D; Stepanyan, S S; Strauch, S; Sytnik, V; Tang, W; Tian, Ye; Ungaro, M; Vlassov, A V; Voskanyan, H; Voutier, E; Walford, N K; Watts, D; Wei, X; Weinstein, L B; Yurov, M; Zachariou, N; Zana, L; Zhang, J; Zhao, Z W; Zonta, I

    2014-08-01

    Exclusive neutral-pion electroproduction (ep-->e'p'pi0) was measured at Jefferson Lab with a 5.75-GeV electron beam and the CLAS detector. Differential cross sections d4sigma/dtdQ2dxBdphipi and structure functions sigmaT+epsilonsigmaL,sigmaTT and σLT as functions of t were obtained over a wide range of Q2 and xB. The data are compared with Regge and handbag theoretical calculations. Analyses in both frameworks find that a large dominance of transverse processes is necessary to explain the experimental results. For the Regge analysis it is found that the inclusion of vector meson rescattering processes is necessary to bring the magnitude of the calculated and measured structure functions into rough agreement. In the handbag framework, there are two independent calculations, both of which appear to roughly explain the magnitude of the structure functions in terms of transversity generalized parton distributions.

  18. Single π+ Electroproduction in the First and Second Resonance Regions Using CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Egiyan, Hovanes [College of William and Mary, Williamsburg, VA (United States)

    2001-01-01

    The study of single pion electroproduction can provide valuable information on the structure of the nucleon and its excited states. Although these reactions have been studied for decades, never has the n π+ channel been measured over the complete phase space of the reaction. The CEBAF Large Acceptance Spectrometer (CLAS) located in Hall B of Jefferson Lab is well-suited for conducting these measurements. The CLAS data were taken using a 1.515 GeV electron beam incident on a liquid H2 target. The cross sections have been extracted, and their phi-dependence has been fit to obtain the sigmaTT, sigmaTL and the sigmaT + epsilon sigmaL linear combination of the structure functions. An analysis program based on the Mainz unitary isobar model was used to analyze the experimental data from the π+ channel only. The resonant amplitudes for P33(1232), SL(1535) and D{sub 13}(1520) were obtained from the fit.

  19. Measurement of azimuthal asymmetries with respect of both beam charge and transverse target polarization in exclusive electroproduction of real photons

    Energy Technology Data Exchange (ETDEWEB)

    Airapetian, A. [DESY Hamburg (Germany); Akopov, N.; Akopov, Z. [Yerevan Physics Institute (AR)] (and others)

    2008-02-15

    Azimuthal asymmetries in exclusive electroproduction of real photons are measured for the first time with respect to transverse target polarisation, providing new constraints on Generalized Parton Distributions. From the same data set on a hydrogen target, new results for the beam-charge asymmetry are also extracted with better precision than those previously reported. By comparing model calculations with measured asymmetries attributed to the interference between the deeply virtual Compton scattering and Bethe-Heitler processes, a model-dependent constraint is obtained on the total angular momenta carried by up and down quarks in the nucleon. (orig.)

  20. Exclusive electroproduction of K+Lambda and K+Sigma(0) final states at Q(2)=0.030-0.055 (GeV/c)(2)

    Czech Academy of Sciences Publication Activity Database

    Achenbach, P.; Gayoso, C. A.; Bernauer, J. C.; Bianchin, S.; Böhm, R.; Borodina, O.; Bosnar, D.; Bösz, M.; Bozkurt, V.; Bydžovský, Petr; Debenjak, L.; Distler, M. O.; Esser, A.; Friscic, I.; Gomez, M.R.; Göküzüm, B.; Griessinger, K.; Jennewein, P.; Kim, E.; Sirca, S.

    2012-01-01

    Roč. 48, č. 14 (2012), s. 1-8 ISSN 1434-6001 R&D Projects: GA ČR GA202/08/0984 Institutional support: RVO:61389005 Keywords : strangeness * meson production * electroproduction Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 2.043, year: 2012

  1. Photo- and pion electroproduction in chiral effective field theory; Photo- und Elektropionproduktion in chiraler effektiver Feldtheorie

    Energy Technology Data Exchange (ETDEWEB)

    Hilt, Marius

    2011-12-13

    This thesis is concerned with pion photoproduction (PPP) and pion electroproduction (PEP) in the framework of manifestly Lorentz-invariant baryon chiral perturbation theory. For that purpose two different approaches are used. Firstly, a one-loop-order calculation up to chiral order O(q{sup 4}) including pions and nucleons as degrees of freedom, is performed to describe the energy dependence of the reactions over a large range. To improve the dependence on the virtuality of the photon in PEP, in a second approach vector mesons are included as explicit degrees of freedom. The latter calculation includes one-loop contributions up to chiral order O(q{sup 3}). Only three of the four physical processes of PPP and PEP can be accessed experimentally. These reactions are measured at several different facilities, e.g. Mainz, Bonn, or Saskatoon. The data obtained there are used to explore the limits of chiral perturbation theory. This thesis is the first complete manifestly Lorentz-invariant calculation up to order O(q{sup 4}) for PPP and PEP, and the first calculation ever for these processes including vector mesons explicitly. Beside the calculation of physical observables, a partial wave decomposition is performed and the most important multipoles are analyzed. They may be extracted from the calculated amplitudes and allow one to examine the nucleon and {delta} resonances. The number of diagrams one has to calculate is very large. In order to handle these expressions, several routines were developed for the computer algebra system Mathematica. For the multipole decomposition, two different programs are used. On the one hand, a modified version of the so-called {chi}MAID has been employed. On the other hand, similar routines were developed for Mathematica. In the end, the different calculations are compared with respect to their applicability to PPP and PEP.

  2. Ratios of helicity amplitudes for exclusive ρ{sup 0} electroproduction on transversely polarized protons

    Energy Technology Data Exchange (ETDEWEB)

    Airapetian, A. [Justus-Liebig Universitaet Giessen, II. Physikalisches Institut, Giessen (Germany); University of Michigan, Randall Laboratory of Physics, Ann Arbor, MI (United States); Akopov, N.; Elbakian, G.; Gharibyan, V.; Marukyan, H.; Petrosyan, A. [Yerevan Physics Institute, Yerevan (Armenia); Akopov, Z.; Borissov, A.; Deconinck, W.; Holler, Y.; Rostomyan, A.; Zihlmann, B. [DESY, Hamburg (Germany); Aschenauer, E.C.; Nowak, W.D. [DESY, Zeuthen (Germany); Augustyniak, W.; Marianski, B.; Trzcinski, A.; Zupranski, P. [National Centre for Nuclear Research, Warsaw (Poland); Belostotski, S.; Kisselev, A.; Manaenkov, S.I.; Veretennikov, D.; Vikhrov, V. [B.P. Konstantinov Petersburg Nuclear Physics Institute, Leningrad Region (Russian Federation); Blok, H.P. [National Institute for Subatomic Physics (Nikhef), Amsterdam (Netherlands); VU University, Department of Physics and Astronomy, Amsterdam (Netherlands); Bryzgalov, V.; Ivanilov, A.; Korotkov, V.; Salomatin, Y. [Institute for High Energy Physics, Moscow Region (Russian Federation); Capitani, G.P.; De Sanctis, E.; Muccifora, V.; Reolon, A.R. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati, Frascati (Italy); Ciullo, G.; Lenisa, P.; Pappalardo, L.L.; Statera, M. [Istituto Nazionale di Fisica Nucleare, Sezione di Ferrara, Ferrara (Italy); Universita di Ferrara, Dipartimento di Fisica e Scienze della Terra, Ferrara (Italy); Contalbrigo, M. [Istituto Nazionale di Fisica Nucleare, Sezione di Ferrara, Ferrara (Italy); De Leo, R.; Lagamba, L.; Vilardi, I. [Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Bari (Italy); Dueren, M. [Justus-Liebig Universitaet Giessen, II. Physikalisches Institut, Giessen (Germany); Ellinghaus, F. [University of Colorado, Nuclear Physics Laboratory, Boulder, CO (United States); Felawka, L. [TRIUMF, Vancouver, BC (Canada); Frullani, S.; Garibaldi, F. [Istituto Nazionale di Fisica Nucleare, Sezione di Roma, Gruppo Collegato Sanita, Rome (Italy); Istituto Superiore di Sanita, Rome (Italy); Gavrilov, G. [DESY, Hamburg (Germany); B.P. Konstantinov Petersburg Nuclear Physics Institute, Leningrad Region (Russian Federation); TRIUMF, Vancouver, BC (Canada); Goloskokov, S.V.; Shutov, V. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Jackson, H.E.; Reimer, P.E. [Argonne National Laboratory, Physics Division, Argonne, IL (United States); Joosten, S. [Ghent University, Department of Physics and Astronomy, Gent (Belgium); University of Illinois, Department of Physics, Urbana, IL (United States); Kaiser, R.; Lehmann, I.; Rosner, G.; Seitz, B. [University of Glasgow, SUPA, School of Physics and Astronomy, Glasgow (United Kingdom); Karyan, G. [DESY, Hamburg (Germany); Yerevan Physics Institute, Yerevan (Armenia); Kozlov, V.; Terkulov, A. [Lebedev Physical Institute, Moscow (Russian Federation); Kravchenko, P. [Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erlangen (Germany); B.P. Konstantinov Petersburg Nuclear Physics Institute, Leningrad Region (Russian Federation); Kroll, P.; Schaefer, A. [Universitaet Regensburg, Institut fuer Theoretische Physik, Regensburg (Germany); Lapikas, L. [National Institute for Subatomic Physics (Nikhef), Amsterdam (Netherlands); Lorenzon, W. [University of Michigan, Randall Laboratory of Physics, Ann Arbor, MI (United States); Miyachi, Y.; Shibata, T.A. [Tokyo Institute of Technology, Department of Physics, Tokyo (Japan); Movsisyan, A. [Istituto Nazionale di Fisica Nucleare, Sezione di Ferrara, Ferrara (Italy); Yerevan Physics Institute, Yerevan (Armenia); Nass, A.; Rith, K. [Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erlangen (Germany); Riedl, C. [DESY, Zeuthen (Germany); University of Illinois, Department of Physics, Urbana, IL (United States); Ryckbosch, D.; Tytgat, M.; Haarlem, Y. van [Ghent University, Department of Physics and Astronomy, Gent (Belgium); Schnell, G. [University of the Basque Country UPV/EHU, Department of Theoretical Physics, Bilbao (Spain); Basque Foundation for Science, IKERBASQUE, Bilbao (Spain); Ghent University, Department of Physics and Astronomy, Gent (Belgium); Truty, R. [University of Illinois, Department of Physics, Urbana, IL (United States); Hulse, C. van [University of the Basque Country UPV/EHU, Department of Theoretical Physics, Bilbao (Spain); Ghent University, Department of Physics and Astronomy, Gent (Belgium); Yaschenko, S. [DESY, Hamburg (Germany); Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erlangen (Germany); Collaboration: The HERMES Collaboration

    2017-06-15

    Exclusive ρ{sup 0}-meson electroproduction is studied by the HERMES experiment, using the 27.6 GeV longitudinally polarized electron/positron beam of HERA and a transversely polarized hydrogen target, in the kinematic region 1.0 GeV{sup 2} < Q{sup 2} < 7.0 GeV{sup 2}, 3.0 GeV < W < 6.3 GeV, and -t{sup '} < 0.4 GeV{sup 2}. Using an unbinned maximum-likelihood method, 25 parameters are extracted. These determine the real and imaginary parts of the ratios of several helicity amplitudes describing ρ{sup 0}-meson production by a virtual photon. The denominator of those ratios is the dominant amplitude, the nucleon-helicity-non-flip amplitude F{sub 0(1)/(2)0(1)/(2)}, which describes the production of a longitudinal ρ{sup 0}-meson by a longitudinal virtual photon. The ratios of nucleon-helicity-non-flip amplitudes are found to be in good agreement with those from the previous HERMES analysis. The transverse target polarization allows for the first time the extraction of ratios of a number of nucleon-helicity-flip amplitudes to F{sub 0(1)/(2)0(1)/(2)}. Results obtained in a handbag approach based on generalized parton distributions taking into account the contribution from pion exchange are found to be in good agreement with these ratios. Within the model, the data favor a positive sign for the π - ρ transition form factor. By also exploiting the longitudinal beam polarization, a total of 71 ρ{sup 0} spin-density matrix elements is determined from the extracted 25 parameters, in contrast to only 53 elements as directly determined in earlier analyses. (orig.)

  3. Ratios of helicity amplitudes for exclusive ρ{sup 0} electroproduction on transversely polarized protons

    Energy Technology Data Exchange (ETDEWEB)

    Airapetian, A. [Giessen Univ. (Germany). 2. Physikalisches Inst.; Michigan Univ., Ann Arbor, MI (United States). Randall Lab. of Physics; Akopov, N. [Yerevan Physics Institute (Armenia); Akopov, Z. [DESY, Hamburg (Germany); Collaboration: HERMES Collaboration; and others

    2017-06-13

    Exclusive ρ{sup 0}-meson electroproduction is studied by the HERMES experiment, using the 27.6 GeV longitudinally polarized electron/positron beam of HERA and a transversely polarized hydrogen target, in the kinematic region 1.0 GeV{sup 2}

  4. Electroproduction of charged pions from 1H, 2H, 40Ca and 208Pb

    International Nuclear Information System (INIS)

    Badalyan, N.N.; Badalyan, R.G.; Chubaryan, M.Ya.

    1994-01-01

    In deep inelastic scattering at squared four- momentum transfers Q 2 >> m c 2 , where the mass m Q of the additive quark is m c ≅ m Q ∼ 0,3 GeV, the virtual photon can transfer its energy to the quark during a time interval τ P ≅ ν/Q 2 . With respect to perturbative QCD, the cross section for this process is ∼ 1/Q 2 ; moreover, during the time interval τ F ≅ ν/m c 2 >> ν P , the point-like configuration must transform into a normal-sized hadron. Between the time interval τ P F , this point-like quark or quark-gluon configuration can interact with nuclear matter with only small cross section. Such a delayed hadronization mechanism will increase the yield of hadrons (in particular, π + -mesons) relative to the case when hadron production can take place at the virtual-photon quark interaction point. This hadronization process can be studied at energies available after the first energy upgrade at CEBAF; namely, at a beam energy of 6.00 GeV. We propose to measure in Hall A the inclusive electroproduction of π ± -mesons on 1 H and π + -mesons on 2 H, 40 Ca and 208 Pb utilizing the (e, e'π ± ) reaction for 1.0 ≤ Q 2 (GeV/c) 2 ≤2.5, at an invariant energy W > 1.92 GeV and at x B = 0.3. From a Q 2 -dependent analysis of the nuclear matter transparency, we can extract information about the space-time scale for the mechanism of quark hadronization. 65 refs., 21 figs., 6 tabs

  5. Beam helicity asymmetries in K{sup +}Λ electroproduction off the proton at low Q{sup 2}

    Energy Technology Data Exchange (ETDEWEB)

    Achenbach, P.; Ayerbe Gayoso, C.; Boehm, R.; Distler, M.O.; Esser, A.; Gomez Rodriguez, M.; Merkel, H.; Mueller, U.; Pochodzalla, J.; Sanchez Majos, S.; Schlimme, B.S.; Schoth, M.; Schulz, F.; Sfienti, C.; Thiel, M. [Johannes Gutenberg-Universitaet, Institut fuer Kernphysik, Mainz (Germany); Borodina, O. [Johannes Gutenberg-Universitaet, Institut fuer Kernphysik, Mainz (Germany); GSI Helmholtz Centre for Heavy Ion Research, Darmstadt (Germany); Bosnar, D.; Friscic, I. [University of Zagreb, Department of Physics, Faculty of Science, Zagreb (Croatia); Bozkurt, V.; Kim, E.; Rappold, C. [GSI Helmholtz Centre for Heavy Ion Research, Darmstadt (Germany); Bydzovsky, P.; Skoupil, D. [Nuclear Physics Institute, Rez (Czech Republic); Debenjak, L.; Sirca, S. [University of Ljubljana and Institut ' ' Jozef Stefan' ' , Ljubljana (Slovenia); Fujii, Y.; Gogami, T.; Hashimoto, O.; Hirose, S.; Kanda, H.; Kaneta, M.; Nagao, S.; Nakamura, S.N.; Tsukada, K. [Tohoku University, Department of Physics, Sendai (Japan); Margaryan, A. [Yerevan Physics Institute, Yerevan (Armenia); Reinhold, J. [Florida International University, Department of Physics, Miami, FL (United States); Saito, T.R. [Johannes Gutenberg-Universitaet, Institut fuer Kernphysik, Mainz (Germany); GSI Helmholtz Centre for Heavy Ion Research, Darmstadt (Germany); Helmholtz Institute Mainz, Mainz (Germany); Sanchez Lorente, A. [Helmholtz Institute Mainz, Mainz (Germany); Tang, L. [Hampton University, Department of Physics, Hampton, VA (United States); Collaboration: A1 Collaboration

    2017-10-15

    Beam helicity asymmetries in the vector ep → e{sup '}K{sup +}Λ reaction have been measured at unprecedentedly low four-momentum transfers left angle Q{sup 2} right angle = 0.05 (GeV/c){sup 2}. At the Mainz Microtron (MAMI), the experiment was performed with a longitudinally polarized beam and an out-of-plane detection of the scattered electron. This experiment probed the associated helicity-dependent structure function dσ{sub LT}{sup {sub '}}/dΩ{sub K}{sup c.m.}, which is sensitive to the details of resonances of the proton. The results were compared to models for kaon electroproduction using effective Lagrangians. The MAMI data is not supporting the Kaon-Maid isobar model, which uses strong longitudinal couplings of the virtual photon to nucleon resonances and predicts a strong peaking of the structure function at forward angles and low Q{sup 2}. The data is also in disagreement with a Regge-plus-resonance model that predicts the incorrect sign of the structure function. The combination of the MAMI results with data taken at higher four-momentum transfers measured at Jefferson Lab indicates a smooth transition in Q{sup 2} without significant changes of the interference pattern in the electroproduction process. (orig.)

  6. Measurement of transverse single-spin asymmetries in inclusive electroproduction at HERMES

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Ruiz, Alejandro

    2012-12-15

    This dissertation describes the measurement of two single-spin asymmetries (SSAs) in the production of particles from inelastic lepton-proton collisions. SSAs are a convenient observable for investigating the spin-dependent part of the electron-proton cross section. The analyzed data were taken by the HERMES experiment at DESY, using a 27.6 GeV electron/positron beam and a static hydrogen target in which the proton spin was polarized transversely to the direction of the beam. In the first case, SSAs were investigated in the inclusive electroproduction of charged pions and kaons. The asymmetries were studied as a function of the hadron momentum, p{sub T}, relative to the direction of the incident beam, and the Feynman variable x{sub F}. In the kinematic range 0.08 GeV

  7. Measurement of transverse single-spin asymmetries in inclusive electroproduction at HERMES

    International Nuclear Information System (INIS)

    Lopez Ruiz, Alejandro

    2012-12-01

    This dissertation describes the measurement of two single-spin asymmetries (SSAs) in the production of particles from inelastic lepton-proton collisions. SSAs are a convenient observable for investigating the spin-dependent part of the electron-proton cross section. The analyzed data were taken by the HERMES experiment at DESY, using a 27.6 GeV electron/positron beam and a static hydrogen target in which the proton spin was polarized transversely to the direction of the beam. In the first case, SSAs were investigated in the inclusive electroproduction of charged pions and kaons. The asymmetries were studied as a function of the hadron momentum, p T , relative to the direction of the incident beam, and the Feynman variable x F . In the kinematic range 0.08 GeV T F T up to about 6% (8%) for pions (kaons) and then decrease again with increasing p T . For negative hadrons the asymmetries were of much smaller magnitude, sometimes positive and sometimes negative. When binned simultaneously in p T and x F , the asymmetries were found to be essentially independent of x F in each slice of p T . The analyzed data were manifestly dominated by hadrons from quasi-real photoproduction. In these reactions, the asymmetry can be related to the hadronic component of the photon and thus to the asymmetry A N observed in hadronic collisions at different energies but not yet fully understood. However, the largest contribution to the measured SSAs are from hadrons produced in deep-inelastic scattering (DIS) reactions, related to the Sivers function, which describes the asymmetric distribution of unpolarized quarks in a transversely polarized proton. Transverse SSAs were also measured in inclusive DIS, where only the scattered beam lepton is detected. In this case, non-zero SSAs would arise from two-photon exchange contributions to the electron-proton cross section. This observable is thus a check of the validity of the one-photon exchange approximation, commonly used in theoretical

  8. Exclusive {rho}{sup 0} meson electroproduction at intermediate square momentum transfer with the CLAS detector (Jefferson laboratory); Electroproduction exclusive de meson vecteur {rho}{sup 0} a virtualite intermediaire a Jlab avec le detecteur CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Hadjidakis, C

    2002-12-01

    This report presents the exclusive {rho}{sup 0} meson electroproduction on the nucleon at intermediate square momentum transfers Q{sup 2} (1.5 < Q{sup 2} < 3 GeV{sup 2}) and above the resonance region. The experiment has been taken place at the Jefferson laboratory with the CLAS detector, with a 4.2 GeV beam energy on an hydrogen target in the February-March 1999 period. We present the results and in particular the L/T separated cross sections. This experimentally unexplored domain experimentally is at the intersection between traditional 'soft' hadronic physics models (VDM and Regge inspired models) and 'hard' pQCD inspired approaches (recently introduced Generalized Parton Distribution). We discuss both approaches and their domain of validity. (author)

  9. Separated structure functions for exclusive K+Λ and K+Σ0 electroproduction at 5.5 GeV measured with CLAS

    Science.gov (United States)

    Carman, D. S.; Park, K.; Raue, B. A.; Adhikari, K. P.; Adikaram, D.; Aghasyan, M.; Amaryan, M. J.; Anderson, M. D.; Anefalos Pereira, S.; Anghinolfi, M.; Avakian, H.; Baghdasaryan, H.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Bono, J.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Celentano, A.; Chandavar, S.; Charles, G.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Doughty, D.; Dupre, R.; El Alaoui, A.; El Fassi, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fersch, R.; Fleming, J. A.; Fradi, A.; Gabrielyan, M. Y.; Gevorgyan, N.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Gohn, W.; Gothe, R. W.; Griffioen, K. A.; Guegan, B.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Harrison, N.; Heddle, D.; Hicks, K.; Ho, D.; Holtrop, M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jo, H. S.; Joo, K.; Keller, D.; Khandaker, M.; Khetarpal, P.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Koirala, S.; Kubarovsky, A.; Kubarovsky, V.; Kuleshov, S. V.; Kvaltine, N. D.; Lewis, S.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Mao, Y.; Martinez, D.; Mayer, M.; McKinnon, B.; Mestayer, M. D.; Meyer, C. A.; Mineeva, T.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Moutarde, H.; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Nasseripour, R.; Nepali, C. S.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Pappalardo, L. L.; Paremuzyan, R.; Park, S.; Pasyuk, E.; Phelps, E.; Phillips, J. J.; Pisano, S.; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Ricco, G.; Rimal, D.; Ripani, M.; Rosner, G.; Rossi, P.; Sabatié, F.; Saini, M. S.; Salgado, C.; Saylor, N. A.; Schott, D.; Schumacher, R. A.; Seder, E.; Seraydaryan, H.; Sharabian, Y. G.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Stepanyan, S. S.; Stepanyan, S.; Stoler, P.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Tang, W.; Taylor, C. E.; Tian, Y.; Tkachenko, S.; Trivedi, A.; Ungaro, M.; Vernarsky, B.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.

    2013-02-01

    We report measurements of the exclusive electroproduction of K+Λ and K+Σ0 final states from an unpolarized proton target using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The separated structure functions σU, σLT, σTT, and σLT' were extracted from the Φ-dependent differential cross sections acquired with a longitudinally polarized 5.499 GeV electron beam. The data span a broad range of momentum transfers Q2 from 1.4 to 3.9 GeV2, invariant energy W from threshold to 2.6 GeV, and nearly the full center-of-mass angular range of the kaon. The separated structure functions provide an unprecedented data sample, which, in conjunction with other meson photo- and electroproduction data, will help to constrain the higher-level analyses being performed to search for missing baryon resonances.

  10. Experimental determination of the interference contributions RLT and RTT to the cross section of the charged-pion electroproduction in the Δ+(1232) resonance region

    International Nuclear Information System (INIS)

    Brunhoeber, H.

    2001-11-01

    The interference terms R LT and R TT that contribute to the cross section of the charged pion electroproduction have been determined in an electron scattering experiment at the accelerator facility ELSA by detecting the outgoing neutron of the nπ + -decay channel by a large acceptance Time-of-Flight spectrometer covering the Δ + (1232) resonance region at the four momentum transfers of 0.638 GeV 2 and 0.8 GeV 2 . (orig.)

  11. Absolute determination of the dominant amplitudes of the electroproduction of neutral pions at the momentum transfer of 0,630 GeV2

    International Nuclear Information System (INIS)

    Bantes, B.

    2003-10-01

    A complete Monte Carlo simulation for the neutral pion electroproduction experiment in the kinematics of the Δ(1232) that was carried out at the accelerator facility ELSA has been developed to correct the data concerning effects like detector resolution efficiencies, acceptances and radiation corrections. Results for the leading amplitudes are extracted at the four momentum transfer of 0.630 GeV 2 . Absolute cross sections are extracted using the well known elastic ep scattering to determine the luminosity. (orig.)

  12. A New Apparatus for Inelastic, Quasi-Elastic and Elastic Cold Neutron Measurements; Un nouveau appareil pour les mesures de diffusion inelastique , quasi-elastique et elastique des neutrons lents; Novyj pribor dlya izmereniya neuprugogo, kvaziuprugogo i uprugogo rasseyaniya kholodnykh nejtrohov; Nuevo aparato para mediciones inelastic as, cuasi elasticas y elasticas de neutrones frios

    Energy Technology Data Exchange (ETDEWEB)

    Otnes, K; Palevsky, H [Brookhaven National Laboratory, Upton, NY (United States)

    1963-01-15

    A new chopper apparatus for use at the Brookhaven High Flux Beam Reactor is now under construction. It is a three-element phased rotof system. The rotors are 80 cm in diameter, run at a maximum speed of 15000 rev/min, and are designed to give three neutron bursts of monochromatic neutrons per revolution. Two rotors spin about a horizontal axis whereas the third operates vertically. The system can be operated with either one, two or three of the chopper elements, depending on the type of measurement that is completed. For inelastic measurements where the neutron gains energy, a double rotor system will be most useful. For this configuration the burst time and wave length spread (full widths at 1/2 maximum) will be 16 {mu}s and 0.16 A for 4 A incident neutrons, and the intensity at the sample (4 x 1.6 cm) will be 2 x 10{sup 6} n/s. For quasi-elastic and elastic neutron measurements the three-rotor configuration will be best suited. The corresponding burst time and wave length spread can be as small as 8 {mu}s and 0.04 A giving an intensity of 10{sup 4} n/s on a sample of (4 X 0.8 c m ), The wave length and time resolution are adjustable between the above two limits in such a way as to obtain the maximum neutron intensity for a given experiment. (author) [French] Un nouveau selecteur destine au reacteur a haut flux de Brookhaven est actuellement en construction. Il s'agit d'un dispositif a trois rotors dephasables. Les rotors ont un diametre de 80 cm, tournent a une vitesse maximum de 15 000 tours pat minute et sont concus de maniere a fournir trois bouffees de neutrons monochromatiques a chaque tour. Deux rotors tournent autour d'un axe horizontal, le troisieme, autour d'un axe vertical. Le dispositif peut fonctionner avec un, deux ou trois elements, selon le type de mesure que l'on se propose de faire. Pour les mesures de diffusion inelastique ou les neutrons gagnent de l'energie, un dispositif a deux rotors sera tres utile. Pour cette configuation, la duree et la

  13. Induced Proton Polarization for pi0 Electroproduction at Q2 = 0.126 GeV2/c2 Around the Delta(1232) Resonance

    International Nuclear Information System (INIS)

    Glen Warren; Ricardo Alarcon; Christopher Armstrong; Burin Asavapibhop; David Barkhuff; William Bertozzi; Volker Burkert; Chen, J.; Jian-Ping Chen; Joseph Comfort; Daniel Dale; George Dodson; Dolfini, S.; Dow, K.; Martin Epstein; Manouchehr Farkhondeh; John Finn; Shalev Gilad; Ralf Gothe; Xiaodong Jiang; Mark Jones; Kyungseon Joo; Karabarbounis, A.; James Kelly; Stanley Kowalski; Kunz, C.; Liu, D.; Lourie, R.W.; Richard Madey; Demetrius Margaziotis; Pete Markowitz; Justin McIntyre; Mertz, C.; Brian Milbrath; Rory Miskimen; Joseph Mitchell; Mukhopadhyay, S.; Costas Papanicolas; Charles Perdrisat; Vina Punjabi; Liming Qin; Paul Rutt; Adam Sarty; Jeffrey Shaw; Soong, S.B.; Tieger, D.; Christoph Tschalaer; William Turchinetz; Paul Ulmer; Scott Van Verst; Vellidis, C.; Lawrence Weinstein; Steven Williamson; Rhett Woo; Alaen Young

    1998-01-01

    We present a measurement of the induced proton polarization P n in π 0 electroproduction on the proton around the Δ resonance. The measurement was made at a central invariant mass and a squared four-momentum transfer of W = 1231 MeV and Q 2 = 0.126 GeV 2 /c 2 , respectively. We measured a large induced polarization, P n = -0.397 ± 0.055 ± 0.009. The data suggest that the scalar background is larger than expected from a recent effective Hamiltonian model

  14. Beam-helicity associated electroproduction of real photons ep {yields} e{gamma}{pi}N in the {Delta}-resonance region

    Energy Technology Data Exchange (ETDEWEB)

    Airapetian, A. [Giessen Univ. (Germany). 2. Physikalisches Inst.; Michigan Univ., Ann Arbor, MI (United States). Randall Laboratory of Physics; Akopov, N. [Yerevan Physics Institute (Argentina); Aschenauer, E.C. [DESY Zeuthen (Germany)] [and others; Collaboration: HERMES Collaboration

    2013-10-15

    The beam-helicity asymmetry in associated electroproduction of real photons, ep {yields} e{gamma}{pi}N, in the {Delta}(1232)-resonance region is measured using the longitudinally polarized HERA positron beam and an unpolarized hydrogen target. Azimuthal Fourier amplitudes of this asymmetry are extracted separately for two channels, ep {yields} e{gamma}{pi}{sup 0}p and ep {yields} e{gamma}{pi}{sup +}n, from a data set collected with a recoil detector. All asymmetry amplitudes are found to be consistent with zero.

  15. Electroproduction of Photons and of Pawns on the Proton in Quadrimoment of Transfer Q2=1.0GeV2. Measure Cross Sections and Extraction of Polarizabilities Generalities; Electroproduction de Photons et de Pions sur le Proton au Quadrimoment de Transfert Q2=1.0GeV2. Mesure des Sections Efficaces et Extraction des Polarisabilites Generalisees

    Energy Technology Data Exchange (ETDEWEB)

    Laveissiere, Geraud [Blaise Pascal Univ., Aubiere (France)

    2001-11-06

    In hadronic physics, the nucleon structure and the quarks confinement are still topical issues. The neutral pion electroproduction and virtual Compton scattering (VCS) reactions allow us to access new observables that describe this structure. This work is focused on the VCS experiment performed at Jefferson Lab in 1998.

  16. First observation of the Λ(1405) line shape in electroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Lu, H. Y.; Schumacher, R. A.; Adhikari, K. P.; Adikaram, D.; Aghasyan, M.; Amaryan, M. J.; Pereira, S. Anefalos; Ball, J.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Cole, P. L.; Collins, P.; Contalbrigo, M.; Cortes, O.; Crede, V.; D’Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Doughty, D.; Dupre, R.; Egiyan, H.; Alaoui, A. El; Fassi, L. El; Eugenio, P.; Fedotov, G.; Fegan, S.; Fleming, J. A.; Gabrielyan, M.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Harrison, N.; Heddle, D.; Hicks, K.; Ho, D.; Holtrop, M.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jo, H. S.; Joo, K.; Keller, D.; Khandaker, M.; Kim, W.; Klein, A.; Klein, F. J.; Koirala, S.; Kubarovsky, A.; Kubarovsky, V.; Kuleshov, S. V.; Lewis, S.; Livingston, K.; MacGregor, I. J. D.; Martinez, D.; Mayer, M.; McKinnon, B.; Meyer, C. A.; Mineeva, T.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Moriya, K.; Moutarde, H.; Munevar, E.; Camacho, C. Munoz; Nadel-Turonski, P.; Nepali, C. S.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Pappalardo, L. L.; Paremuzyan, R.; Park, K.; Park, S.; Pasyuk, E.; Peng, P.; Phelps, E.; Phillips, J. J.; Pisano, S.; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Rimal, D.; Ripani, M.; Rosner, G.; Rossi, P.; Sabatié, F.; Saini, M. S.; Salgado, C.; Schott, D.; Seder, E.; Seraydaryan, H.; Sharabian, Y. G.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Stepanyan, S. S.; Stoler, P.; Strauch, S.; Taiuti, M.; Tang, W.; Tian, Ye; Tkachenko, S.; Torayev, B.; Vernarsky, B.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Weygand, D. P.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.

    2013-10-01

    We report the first observation of the line shape of the Λ ( 1405 ) from electroproduction, and show that it is not a simple Breit-Wigner resonance. Electroproduction of K + Λ ( 1405 ) off the proton was studied by using data from CLAS at Jefferson Lab in the range 1.0 < Q 2 < 3.0 (GeV/ c ) 2 . The analysis utilized the decay channels Σ + π - of the Λ ( 1405 ) and p π 0 of the Σ + . Neither the standard Particle Data Group resonance parameters, nor free parameters fitting to a single Breit-Wigner resonance represent the line shape. In our fits, the line shape corresponds approximately to predictions of a two-pole meson-baryon picture of the Λ ( 1405 ) , with a lower mass pole near 1368 MeV/ c 2 and a higher mass pole near 1423 MeV/ c 2 . Furthermore, with increasing photon virtuality the mass distribution shifts toward the higher mass pole.

  17. Axial structure of the nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Veronique Bernard; Latifa Elouadrhiri; Ulf-G Meissner

    2002-01-01

    We review the current status of experimental and theoretical understanding of the axial nucleon structure at low and moderate energies. Topics considered include (quasi)elastic (anti)neutrino-nucleon scattering, charged pion electroproduction off nucleons and ordinary as well as radiative muon capture on the proton.

  18. Radiative corrections to the beam spin asymmetry in photon electroproduction e polarized p {yields} ep{gamma}

    Energy Technology Data Exchange (ETDEWEB)

    Fonvieille, H.; Bensafa, I. [LPC-Clermont-Fd, Universite Blaise Pascal, F-63170 Aubiere Cedex (France)

    2006-11-15

    We have measured at MAMI the beam single spin asymmetry (SSA) in exclusive photon electroproduction (e polarized p {yields} ep{gamma}) with a longitudinally polarized beam, in the region of the {delta}(1232) resonance. In this document the value of the radiative correction to this asymmetry is obtained for our kinematics. Although the correction is expected to be very small and negligible, its value is needed as a confirmation and for the purpose of systematic error estimate. The parameter of kinematics are given as follows: four-momentum transfer of the virtual photon, Q{sup 2} = 0.35 GeV{sup 2}; total energy in the ({gamma}p) center of mass, W=1.190 GeV; polarization of the virtual photon, {epsilon}=0.48; azimuthal angle (lepton-hadron planes), {phi} = 220 angle; polar angle of Compton scattering in center of mass, {theta}{sub {gamma}}{sub {gamma}} in [0 angle, 40 angle]; incoming electron beam energy, E{sub e} = 0.88 GeV; scattered electron energy, E{sub 0}' = 0.40 GeV; polar angle of scattered electron {theta}{sub e} = 59.9 angle. The radiative correction is calculated by the radcorr code written by M. Vanderhaeghen, in a version adapted to beam spin asymmetries.In practice, the conclusions are twofold: - the asymmetry that was measured in the VCS channel does not need to be corrected for radiative effects, given the large statistical error bar attached to the experimental values (an asymmetry of 1-10 % with a statistical error bar of 3-4 %); - a systematic error {delta}SSA{sub syst} on the asymmetry will be considered, related to uncertainties in the calculation of the radiative correction (at least two of them have been mentioned here: the cross section model and the soft photon limit). To estimate this error a 100 % variation of the radiative correction was assumed. For the radiative correction itself the maximal value found was taken. Therefore one can take: {delta}SSA{sub syst} = {+-}2.7 x 10{sup -3}.

  19. Radiative corrections to the beam spin asymmetry in photon electroproduction e polarized p → epγ

    International Nuclear Information System (INIS)

    Fonvieille, H.; Bensafa, I.

    2006-11-01

    We have measured at MAMI the beam single spin asymmetry (SSA) in exclusive photon electroproduction (e polarized p → epγ) with a longitudinally polarized beam, in the region of the Δ(1232) resonance. In this document the value of the radiative correction to this asymmetry is obtained for our kinematics. Although the correction is expected to be very small and negligible, its value is needed as a confirmation and for the purpose of systematic error estimate. The parameter of kinematics are given as follows: four-momentum transfer of the virtual photon, Q 2 = 0.35 GeV 2 ; total energy in the (γp) center of mass, W=1.190 GeV; polarization of the virtual photon, ε=0.48; azimuthal angle (lepton-hadron planes), φ = 220 angle; polar angle of Compton scattering in center of mass, θ γγ in [0 angle, 40 angle]; incoming electron beam energy, E e = 0.88 GeV; scattered electron energy, E 0 ' = 0.40 GeV; polar angle of scattered electron θ e = 59.9 angle. The radiative correction is calculated by the radcorr code written by M. Vanderhaeghen, in a version adapted to beam spin asymmetries.In practice, the conclusions are twofold: - the asymmetry that was measured in the VCS channel does not need to be corrected for radiative effects, given the large statistical error bar attached to the experimental values (an asymmetry of 1-10 % with a statistical error bar of 3-4 %); - a systematic error ΔSSA syst on the asymmetry will be considered, related to uncertainties in the calculation of the radiative correction (at least two of them have been mentioned here: the cross section model and the soft photon limit). To estimate this error a 100 % variation of the radiative correction was assumed. For the radiative correction itself the maximal value found was taken. Therefore one can take: ΔSSA syst = ±2.7 x 10 -3

  20. Exchange mechanisms for $\\pi^{-}p\\rightarrow\\rho^{0}$n and $\\rho-\\omega$ interference

    CERN Document Server

    Estabrooks, P G; Michael, C

    1974-01-01

    The 17 GeV/c pi /sup -/p to rho /sup 0/n production amplitudes are decomposed into pi , A/sub 2/ and non-evasive exchange contributions. Independent support for this description comes from the observed rho - omega interference effects and from the energy dependence of rho /sup 0/ production data. (18 refs).

  1. Fotoproducción coherente de $\\rho^{0}$ en el LHC

    CERN Document Server

    Cruz Albino, Rigoberto; Tapia Takaki, Daniel

    Coherent photoproduction of ½0 mesons in ultra-peripheral Pb-Pb collisions at p sNN = 2.76 TeV is measured for the first time at the LHC and also we show the preliminary results for p-Pb collisions at p sNN = 5.02 TeV. In Pb-Pb collisions the invariant mass and transverse momentum distributions for ½0 production are studied in the ¼+¼¡ decay channel at mid-rapidity. The production cross section in the rapidity range |y|<0.5 is found to be d¾/dy=425§10(est.)+42 ¡50(sist.) mb. Coherent ½0 production is studied with and without requirement of nuclear breakup, and the fractional yields for various breakup scenarios are presented. The results are compared with those from lower energies and with model predictions. In p-Pb collisions the invariant mass and transverse momentum distributions for ½0 production are studied in the ¼+¼¡ decay channel on 7 different rapidity bins corresponding to different energies (Pb-p), also a measurement is made in the rapidity range |y|<0.5 at hW°pi= 82 GeV for bot...

  2. Inclusive Photoproduction of rho^0, K^{*0} and phi Mesons at HERA

    CERN Document Server

    Aaron, F.D.; Andreev, V.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Backovic, S.; Baghdasaryan, A.; Barrelet, E.; Bartel, W.; Begzsuren, K.; Behnke, O.; Belousov, A.; Berger, N.; Bizot, J.C.; Boudry, V.; Bozovic-Jelisavcic, I.; Bracinik, J.; Brandt, G.; Brinkmann, M.; Brisson, V.; Bruncko, D.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Cantun Avila, K.B.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Cholewa, A.; Contreras, J.G.; Coughlan, J.A.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Daum, K.; Deak, M.; de Boer, Y.; Delcourt, B.; Del Degan, M.; Delvax, J.; De Roeck, A.; De Wolf, E.A.; Diaconu, C.; Dodonov, V.; Dossanov, A.; Dubak, A.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eliseev, A.; Elsen, E.; Falkiewicz, A.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Fischer, D.-J.; Fleischer, M.; Fomenko, A.; Gabathuler, E.; Gayler, J.; Ghazaryan, Samvel; Glazov, A.; Glushkov, I.; Goerlich, L.; Gogitidze, N.; Gouzevitch, M.; Grab, C.; Greenshaw, T.; Grell, B.R.; Grindhammer, G.; Habib, S.; Haidt, D.; Hansson, M.; Helebrant, C.; Henderson, R.C.W.; Hennekemper, E.; Henschel, H.; Herbst, M.; Herrera, G.; Hildebrandt, M.; Hiller, K.H.; Hoffmann, D.; Horisberger, R.; Hreus, T.; Jacquet, M.; Janssen, M.E.; Janssen, X.; Jemanov, V.; Jonsson, L.; Jung, Andreas Werner; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I.R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Kluge, T.; Knutsson, A.; Kogler, R.; Korbel, V.; Kostka, P.; Kraemer, M.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Kruger, K.; Kutak, K.; Landon, M.P.J.; Lange, W.; Lastovicka-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Li, G.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lytkin, L.; Makankine, A.; Malinovski, E.; Marage, P.; Marti, Ll.; Martyn, H.-U.; Maxfield, S.J.; Mehta, A.; Meier, K.; Meyer, A.B.; Meyer, H.; Meyer, H.; Meyer, J.; Michels, V.; Mikocki, S.; Milcewicz-Mika, I.; Moreau, F.; Morozov, A.; Morris, J.V.; Mozer, Matthias Ulrich; Mudrinic, M.; Muller, K.; Murin, P.; Naroska, B.; Naumann, Th.; Newman, P.R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Olivier, B.; Olsson, J.E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Pandurovic, M.; Papadopoulou, Th.; Pascaud, C.; Patel, G.D.; Pejchal, O.; Perez, E.; Petrukhin, A.; Picuric, I.; Piec, S.; Pitzl, D.; Placakyte, R.; Polifka, R.; Povh, B.; Preda, T.; Radescu, V.; Rahmat, A.J.; Raicevic, N.; Raspiareza, A.; Ravdandorj, T.; Reimer, P.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rotaru, M.; Ruiz Tabasco, J.E.; Rurikova, Z.; Rusakov, S.; Salek, D.; Sankey, D.P.C.; Sauter, M.; Sauvan, E.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schoning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shaw-West, R.N.; Sheviakov, I.; Shtarkov, L.N.; Shushkevich, S.; Sloan, T.; Smiljanic, Ivan; Soloviev, Y.; Sopicki, P.; South, D.; Spaskov, V.; Specka, Arnd E.; Staykova, Z.; Steder, M.; Stella, B.; Stoicea, G.; Straumann, U.; Sunar, D.; Sykora, T.; Tchoulakov, V.; Thompson, G.; Thompson, P.D.; Toll, T.; Tomasz, F.; Tran, T.H.; Traynor, D.; Trinh, T.N.; Truol, P.; Tsakov, I.; Tseepeldorj, B.; Turnau, J.; Urban, K.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Vinokurova, S.; Volchinski, V.; von den Driesch, M.; Wegener, D.; Wissing, Ch.; Wunsch, E.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhokin, A.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.

    2009-01-01

    Inclusive non-diffractive photoproduction of rho(770)^0, K^*(892)^0 and phi(1020) mesons is investigated with the H1 detector in ep collisions at HERA. The corresponding average \\gamma p centre-of-mass energy is 210 GeV. The mesons are measured in the transverse momentum range 0.5

  3. Rho0 Photoproduction in Ultra-Peripheral Relativistic Heavy Ion Collisions with STAR

    Energy Technology Data Exchange (ETDEWEB)

    STAR Coll

    2007-12-20

    Photoproduction reactions occur when the electromagnetic field of a relativistic heavy ion interacts with another heavy ion. The STAR collaboration presents a measurement of {rho}{sup 0} and direct {pi}{sup +}{pi}{sup -} photoproduction in ultra-peripheral relativistic heavy ion collisions at {radical}s{sub NN} = 200 GeV. We observe both exclusive photoproduction and photoproduction accompanied by mutual Coulomb excitation. We find a coherent cross-section of {sigma}(AuAu {yields} Au*Au* {rho}{sup 0}) = 530 {+-} 19 (stat.) {+-} 57 (syst.) mb, in accord with theoretical calculations based on a Glauber approach, but considerably below the predictions of a color dipole model. The {rho}{sup 0} transverse momentum spectrum (p{sub T}{sup 2}) is fit by a double exponential curve including both coherent and incoherent coupling to the target nucleus; we find {sigma}{sub inc}/{sigma}{sub coh} = 0.29 {+-} 0.03 (stat.) {+-} 0.08 (syst.). The ratio of direct {pi}{sup +}{pi}{sup -} production is comparable to that observed in {gamma}p collisions at HERA, and appears to be independent of photon energy. Finally, the measured {rho}{sup 0} spin helicity matrix elements agree within errors with the expected s-channel helicity conservation.

  4. Deep Inelastic Exclusive $\\rho^0$ Production using 485-GeV Muons

    Energy Technology Data Exchange (ETDEWEB)

    Schmitt, Michael Henry [Harvard Univ., Cambridge, MA (United States)

    1992-01-01

    Neutral vector mesons share the quantum numbers as the photon, consequently, they are produced copiously in diffractive interactions of photons. The lightest of these, the $p^0$ meson, have been studied in the absorption of high energy virtual photons on hydrogen and deuterium. The mass spectrum, decay distribution, and momentum transfer to the target nucleon has been studied as a function of the kinematic variables. The interference of the two-pion resonance and continuum is constant as a function of the virtual photon mass, $Q^2$ • The $p^0$ polarization changes from purely transverse at low $Q^2$ to predominantly longitudinal at high $Q^2$. The azimuthal decay distribution conforms to the expected form, including terms for transverse-transverse and transverse-longitudinal interference. The diffractive slope parameter declines only slightly with $Q^2$ , indicating that for $Q^2$ up to approximately 4 Ge$V^2$ , production of exclusive p0 mesons is_ a diffractive process .

  5. Target and beam-target spin asymmetries in exclusive π+ and π- electroproduction with 1.6- to 5.7-GeV electrons

    Science.gov (United States)

    Bosted, P. E.; Biselli, A. S.; Careccia, S.; Dodge, G.; Fersch, R.; Guler, N.; Kuhn, S. E.; Pierce, J.; Prok, Y.; Zheng, X.; Adhikari, K. P.; Adikaram, D.; Akbar, Z.; Amaryan, M. J.; Anefalos Pereira, S.; Asryan, G.; Avakian, H.; Badui, R. A.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Boiarinov, S.; Briscoe, W. J.; Bültmann, S.; Burkert, V. D.; Cao, T.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Chetry, T.; Ciullo, G.; Clark, L.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; Deur, A.; Djalali, C.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Eugenio, P.; Fanchini, E.; Fedotov, G.; Filippi, A.; Fleming, J. A.; Forest, T. A.; Fradi, A.; Garçon, M.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gleason, C.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guo, L.; Hafidi, K.; Hanretty, C.; Harrison, N.; Hattawy, M.; Heddle, D.; Hicks, K.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Joosten, S.; Keller, D.; Khandaker, M.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuleshov, S. V.; Lanza, L.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; McCracken, M. E.; McKinnon, B.; Meyer, C. A.; Minehart, R.; Mirazita, M.; Mokeev, V.; Movsisyan, A.; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Net, L. A.; Ni, A.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Peng, P.; Phelps, W.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Simonyan, A.; Skorodumina, Iu.; Smith, G. D.; Sparveris, N.; Stankovic, Ivana; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Taiuti, M.; Tian, Ye; Torayev, B.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

    2016-11-01

    Beam-target double-spin asymmetries and target single-spin asymmetries in exclusive π+ and quasiexclusive π- electroproduction were obtained from scattering of 1.6- to 5.7-GeV longitudinally polarized electrons from longitudinally polarized protons (for π+) and deuterons (for π-) using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The kinematic range covered is 1.1 1.5 GeV. Very large target-spin asymmetries are observed for W >1.6 GeV. When combined with cross-section measurements, the present results can provide powerful constraints on nucleon resonance amplitudes at moderate and large values of Q2, for resonances with masses as high as 2.3 GeV.

  6. Neutral pion electroproduction and virtual Compton scattering on proton with four-momentum transfer squared Q2 = 1 GeV2. Measurement of cross-sections and of generalized polarizabilities

    International Nuclear Information System (INIS)

    Laveissiere, G.

    2001-11-01

    In hadronic physics, the nucleon structure and the quarks confinement are still topical issues. The neutral pion electroproduction and virtual Compton scattering (VCS) reactions allow us to access new observables that describe this structure. This work is focussed on the VCS experiment performed at Jefferson Lab in 1998. The 4 GeV electron beam is scattered off a cryogenic hydrogen target, and the scattered electron and recoiled proton are detected in coincidence in the twin hall A spectrometers. The photon (pion) is reconstructed using a missing particle technique. The data analysis allowed to extract the cross sections relative to both process at four-momentum transfer squared Q 2 = 1 GeV 2 . The VCS cross section has been extracted for the first time in the proton resonance region (W between 1.O and 2.0 GeV) through the photon electroproduction reaction. Around the pion-production threshold up to the Delta(1232) resonance region, these results lead to the measurement of the generalized polarizabilities, that describe the proton structure in the same way as the elastic form factors. Moreover, the neutral pion electroproduction cross section measurement in the resonance region has brought new constraints on the existing phenomenological models. (author)

  7. Transverse-target single-spin azimuthal asymmetry in hard exclusive electroproduction of single pions at HERMES

    Energy Technology Data Exchange (ETDEWEB)

    Hristova, I.

    2007-12-15

    .04}(syst). As a function of t', the measured values of this amplitude increase as {radical}(-t') and at larger vertical stroke t' vertical stroke the corrected ones approach the prediction, however, within their large statistical uncertainties. The phenomenology of hard exclusive electroproduction of pions is explained at present in terms of the so called QCD factorisation theorem: the amplitude for the cross section is given as a convolution of a hard scattering part calculable in perturbative quantum chromodynamics, a distribution amplitude describing the pion, and generalised parton distributions that parameterise the complex structure of the proton. Using QCD factorisation and models for the particles' structure, the value of the leading amplitude A{sup sin({phi}-{phi}{sub S})}{sub UT} is predicted to be of order unity. Although our results appear to support this prediction, a direct and more precise data-to-theory comparison requires larger statistics and improved detector capabilities than available for the present measurement. (orig.)

  8. Transverse-target single-spin azimuthal asymmetry in hard exclusive electroproduction of single pions at HERMES

    International Nuclear Information System (INIS)

    Hristova, I.

    2007-12-01

    corrected ones approach the prediction, however, within their large statistical uncertainties. The phenomenology of hard exclusive electroproduction of pions is explained at present in terms of the so called QCD factorisation theorem: the amplitude for the cross section is given as a convolution of a hard scattering part calculable in perturbative quantum chromodynamics, a distribution amplitude describing the pion, and generalised parton distributions that parameterise the complex structure of the proton. Using QCD factorisation and models for the particles' structure, the value of the leading amplitude A sin(φ-φ S ) UT is predicted to be of order unity. Although our results appear to support this prediction, a direct and more precise data-to-theory comparison requires larger statistics and improved detector capabilities than available for the present measurement. (orig.)

  9. Neutral pion electroproduction and virtual Compton scattering on proton with four-momentum transfer squared Q{sup 2} = 1 GeV{sup 2}. Measurement of cross-sections and of generalized polarizabilities; Electroproduction de photons et de pions sur le proton au quadrimoment de transfert Q{sup 2} = 1.0 GeV{sup 2}. Mesure des sections efficaces et extraction des polarisabilites generalisees

    Energy Technology Data Exchange (ETDEWEB)

    Laveissiere, G

    2001-11-01

    In hadronic physics, the nucleon structure and the quarks confinement are still topical issues. The neutral pion electroproduction and virtual Compton scattering (VCS) reactions allow us to access new observables that describe this structure. This work is focussed on the VCS experiment performed at Jefferson Lab in 1998. The 4 GeV electron beam is scattered off a cryogenic hydrogen target, and the scattered electron and recoiled proton are detected in coincidence in the twin hall A spectrometers. The photon (pion) is reconstructed using a missing particle technique. The data analysis allowed to extract the cross sections relative to both process at four-momentum transfer squared Q{sup 2} = 1 GeV{sup 2}. The VCS cross section has been extracted for the first time in the proton resonance region (W between 1.O and 2.0 GeV) through the photon electroproduction reaction. Around the pion-production threshold up to the Delta(1232) resonance region, these results lead to the measurement of the generalized polarizabilities, that describe the proton structure in the same way as the elastic form factors. Moreover, the neutral pion electroproduction cross section measurement in the resonance region has brought new constraints on the existing phenomenological models. (author)

  10. Simulating moist convection with a quasi-elastic sigma coordinate model

    CSIR Research Space (South Africa)

    Bopape, Mary-Jane M

    2012-09-01

    Full Text Available Cloud Resolving Models (CRMs) employ microphysics parameterisations which are grouped into bin and bulk approaches. Bulk Microphysics Parameterisation (BMP) schemes specify a functional form for the particle distribution and predict one or more...

  11. Simulating moist convection with a quasi-elastic sigma coordinate model

    CSIR Research Space (South Africa)

    Bopape, Mary-Jane M

    2012-10-01

    Full Text Available : Corrected TOGA COARE Sounding Humidity Data: Impact on Diagnosed Properties of Convection and Climate over the Warm Pool. Journal of Climate, 12, 2370-2384. WW, X Wu and MW Moncrieff, 1996: Cloud-Resolving Modeling of Tropical Cloud Systems during Phase... during the suppressed phase of a Madden-Julian Oscillation: Comparing single-column models with cloud resolving models. Quarterly Journal of the Royal Meteorological Society, 1-22. Sun S and W Sun, 2002: A One-dimensional Time Dependent Cloud Model...

  12. Chiral symmetry restoration and quasi-elastic electron-nucleus scattering

    International Nuclear Information System (INIS)

    Henley, E.M.; Krein, G.

    1989-01-01

    Chiral symmetry is known to be an important concept in hadronic interactions. It holds in QCD, but is known to be broken at low energies. It is therefore useful to study chiral symmetry and its breaking together with its consequences in nuclear physics. It is the latter phenomena we consider here. It is difficult to study nonperturbative QCD at low energies and models are needed. The Nambu-Jona-Lasinio (NJL) model fits this category; it incorporates chiral symmetry and its breaking, and allows one to study its effects in nucleons and nuclei. In particular, the constituent quark mass varies with density (ρ) and temperature (T). At high ρ and T chiral symmetry is restored. It is the ρ dependence which yields important effects in electron scattering due to partial restoration of chiral symmetry in nuclei. We begin with the NJL model with a small chiral symmetry breaking

  13. Quasi-elastic production of charmed baryons in neutrino-nUcleon interactions

    International Nuclear Information System (INIS)

    Zhizhin, E.D.; Nikitin, Yu.P.; Fanchenko, M.S.

    1983-01-01

    Quasielastic production of charmed baryons Λsub(c)sup(+), Σsub(c)sup(+), and Σsub(c)sup(++) in neutrino reactions on nucleons is studied. Differential and total cross sections are calculated for two sets of the parameters Msub(V), Msub(A) which determine the form factors of weak transitions of nucleons into charmed baryons. The chosen parameter values allow to obtain the cross sections which overlap the entire uncertainty range of theoretical predictions. The authors pay attention to an important kinematical effect that for monochromatic neutrino beams the values of the charmed baryon emission angles are limited (THETA < THETAsub(max)) and the differential cross section dσ/dΩ strongly increases in the vicinity of the angles THETA=THETAsub(max). Possibilities in experimental studying of the above processes and in extracting unique information on the structure of charmed baryons from experimental data are

  14. Sub-barrier fusion and near-barrier quasi-elastic scattering

    International Nuclear Information System (INIS)

    Kolata, J.J.; Tighe, R.J.

    1990-01-01

    Elastic scattering of 32 S on 58,64 Ni and fusion of 32 S+ 58,64 Ni and 34 S+ 64 Ni have been measured at energies near the Coulomb barrier. Our results differ in several important respects from previous measurements on these systems. Coupled-channels calculations which explicitly allow for inelastic excitation and single-nucleon transfer reproduce the main features of the new data. Near-barrier elastic scattering of 48 Ca on 40 Ca has also been measured. These data provide evidence for the effect of strong coupling to positive Q-value channels other than single-nucleon transfer. 18 refs., 3 figs

  15. Quasi-elastic reactions: an interplay of reaction dynamics and nuclear structure

    Directory of Open Access Journals (Sweden)

    Recchia F.

    2011-10-01

    Full Text Available Multinucleon transfer reactions have been investigated in 40Ar+208Pb with the Prisma+Clara set-up. The experimental differential cross sections of different neutron transfer channels have been obtained at three different angular settings taking into account the transmission through the spectrometer. The experimental yields of the excited states have been determined via particle-γ coincidences. In odd Ar isotopes, we reported a signif cant population of 11/2− states, reached via neutron transfer. Their structure matches a stretched conf guration of the valence neutron coupled to vibration quanta.

  16. Angular distributions of elastic and quasi elastic heavy-ion collisions. Pattern analysis

    International Nuclear Information System (INIS)

    Da Silveira, R.

    1980-06-01

    The emergence, as well as the evolution, of the most typical patterns observed in the angular distributions of elastic scattering and surface transfer between heavy-nuclei, is discussed. Starting from the semi-classical approximation, Thom's classification theorem is evoked to further illuminate the connection between these patterns and the collision parameters

  17. Methyl group rotation and segmental motion in atactic polypropylene. An incoherent quasi elastic neutron scattering investigation

    International Nuclear Information System (INIS)

    Arrighi, V.; Triolo, A.

    1999-01-01

    Complete text of publication follows. Results from the analysis of recent quasielastic neutron scattering (QENS) experiments on atactic polypropylene (aPP), are presented both in the sub-T g and above T g regimes. Experiments were carried out on the IRIS (ISIS, Rutherford Appleton Laboratory, UK) and IN10 (ILL FR) spectrometers in the temperature range from 140 to 400 K. Different instrumental resolutions were used in order to cover a wide energy window. The high resolution data collected on IN10 using the fixed energy scan technique, give clear evidence of two separate dynamic processes that we attribute to methyl group rotational hopping (below T g ) and to segmental motion (above T g ), respectively. Data were fitted using a model involving a distribution of relaxation rates. The IN10 results are used in interpreting and analyzing the QENS data from the IRIS spectrometer. In order to exploit the different energy resolutions of IRIS, Fourier inversion of the experimental data was carried out. This approach to data analysis allows us to widen the energy range available for data analysis. Due to the high activation energy of the methyl group hopping in aPP, this motion overlaps with the segmental relaxation, thus making analysis of high temperature data quite complex. The IN10 results are employed in order to perform data analysis in terms of two distinct processes. (author)

  18. Production of Z0 bosons in elastic and quasi-elastic ep collisions at HERA

    International Nuclear Information System (INIS)

    Abramowicz, H.; Abt, I.; Adamczyk, L.

    2012-10-01

    The production of Z 0 bosons in the reaction ep → eZ 0 p (*) , where p (*) stands for a proton or a low-mass nucleon resonance, has been studied in ep collisions at HERA using the ZEUS detector. The analysis is based on a data sample collected between 1996 and 2007, amounting to 496 pb -1 of integrated luminosity. The Z 0 was measured in the hadronic decay mode. The elasticity of the events was ensured by a cut on η max max is the maximum pseudorapidity of energy deposits in the calorimeter defined with respect to the proton beam direction. A signal was observed at the Z 0 mass. The cross section of the reaction ep → eZ 0 p (*) was measured to be σ (ep → eZ 0 p (*) ) = 0.13 ± 0.06 (stat.) ± 0.01 (syst.) pb, in agreement with the Standard Model prediction of 0.16 pb. This is the first measurement of Z 0 production in ep collisions.

  19. Properties of quasi-elastic processes due to exchange of one dual pomeron

    International Nuclear Information System (INIS)

    Gedalin, Eh.V.; Gurvich, E.G.

    1975-01-01

    The asymptotic (at S tending to infinity) characteristics of four-particle amplitudes of diffraction scattering of resonance states in the dual-resonance model is considered in the lower order of the dual theory of perturbations. It is shown that for transverse transferred momentum K→0, at least for part of the spectrum of states of the dual resonance model - i.e. of the transverse states -, the scattering amplitudes are zero, except for the elastically scattered ones, which are all identical. (author)

  20. Heavy ion elastic and quasi-elastic scattering above E/A = 30 MeV

    International Nuclear Information System (INIS)

    Barrette, J.

    1986-05-01

    At high energy, heavy-ion elastic scattering probes the ion-ion potential in a large domain much inside the strong absorption radius. This results in a more precise determination of the real part of the nuclear potential and a consistent picture of its evolution with energy begins to emerge. It is relatively similar to that observed in light ion scattering. Even if the inelastic angular distributions seem to contain less refractive or interior contribution, coupled channel effects from these states are still important at least up to 20 MeV/n. Heavy-ion induced transfer reactions to discrete states have small cross sections but present a very strong selectivity for states with the highest available spin and could thus provide new and interesting spectroscopic information

  1. Effects of hadronic colour structure in quasi-elastic and charge-exchange scattering on nuclei

    International Nuclear Information System (INIS)

    Kopeliovich, B.Z.; Zakharov, B.G.

    1986-01-01

    Effects of hadronic hidden colour screening are considered in hadron-nucleus interaction. It is shown that in the quasi-free charge exchange-reaction nuclear matter becomes transparent for the scattered hadron if the momentum transfer is large enough. The available experimental data confirm this prediction of QCD

  2. Motility analysis of circularly swimming bull spermatozoa by quasi-elastic light scattering and cinematography.

    Science.gov (United States)

    Craig, T; Hallett, F R; Nickel, B

    1982-04-01

    The Rayleigh-Gans-Debye approximation is used to predict the electric field autocorrelation functions of light scattered from circularly swimming bull spermatozoa. Using parameters determined from cinematography and modeling the cells as coated ellipsoids of semiaxes a = 0.5 micrometers, b = 2.3 micrometers, and c = 9.0 micrometers, we were able to obtain model spectra that mimic the data exactly. A coat is found to be a necessary attribute of the particle. It is also clear that these model functions at 15 degrees may be represented by the relatively simple function used before by Hallett et al. (1978) to fit data from circularly swimming cells, thus giving some physical meaning to these functional shapes. Because of this agreement the half-widths of experimental functions can now be interpreted in terms of an oscillatory frequency for the movement of the circularly swimming cell. The cinematographic results show a trend to chaotic behavior as the temperature of the sample is increased, with concomitant decrease in overall efficiency. This is manifested by a decrease in oscillatory frequency and translational speed.

  3. Production of Z 0 bosons in elastic and quasi-elastic ep collisions at HERA

    NARCIS (Netherlands)

    Abramowicz, A.; et al., [Unknown; Koffeman, E.; Kooijman, P.

    2013-01-01

    The production of Z0Z0 bosons in the reaction ep→eZ0p(*)ep→eZ0p(*), where )p(*) stands for a proton or a low-mass nucleon resonance, has been studied in ep collisions at HERA using the ZEUS detector. The analysis is based on a data sample collected between 1996 and 2007, amounting to 496 pb−1496

  4. Production of Z0 bosons in elastic and quasi-elastic ep collisions at HERA

    NARCIS (Netherlands)

    Abramowicz, H.; Kooijman, P.; Zotkin, D.S.

    2013-01-01

    The production of Z0 bosons in the reaction ep →eZ0 p(∗), where p(∗) stands for a proton or a lowmass nucleon resonance, has been studied in ep collisions at HERA using the ZEUS detector. The analysis is based on a data sample collected between 1996 and 2007, amounting to 496 pb−1 of integrated

  5. Measurement of the unpolarized K+Λ and K+Σ0 electroproduction cross-section off the proton with KAOS-spectrometer

    International Nuclear Information System (INIS)

    Sanchez Majos, Salvador

    2012-02-01

    The new stage of the Mainz Microtron, MAMI, at the Institute for Nuclear Physics of the Johannes Gutenberg-University, operational since 2007, allows open strangeness experiments to be performed. Covering the lack of electroproduction data at very low Q 2 , p(e,K + )Λ and p(e,K + )Σ 0 , reactions have been studied at Q 2 =0.036 (GeV/c) 2 and Q 2 =0.05(GeV/c) 2 in a large angular range. Cross-section at W=1.75 GeV are given in angular bins and compared with the predictions of Saclay-Lyon and Kaon Maid isobaric models. We conclude that the original Kaon-Maid model, which has large longitudinal couplings of the photon to nucleon resonances, is unphysical. Extensive studies for the suitability of silicon photomultipliers as read out devices for a scintillating fiber tracking detector, with potential applications in both positive and negative arms of the spectrometer, are presented as well.

  6. Measurement of the unpolarized K{sup +}{lambda} and K{sup +}{sigma}{sup 0} electroproduction cross-section off the proton with KAOS-spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Majos, Salvador

    2012-02-15

    The new stage of the Mainz Microtron, MAMI, at the Institute for Nuclear Physics of the Johannes Gutenberg-University, operational since 2007, allows open strangeness experiments to be performed. Covering the lack of electroproduction data at very low Q{sup 2}, p(e,K{sup +}){lambda} and p(e,K{sup +}){sigma}{sup 0}, reactions have been studied at Q{sup 2}=0.036 (GeV/c){sup 2} and Q{sup 2}=0.05(GeV/c){sup 2} in a large angular range. Cross-section at W=1.75 GeV are given in angular bins and compared with the predictions of Saclay-Lyon and Kaon Maid isobaric models. We conclude that the original Kaon-Maid model, which has large longitudinal couplings of the photon to nucleon resonances, is unphysical. Extensive studies for the suitability of silicon photomultipliers as read out devices for a scintillating fiber tracking detector, with potential applications in both positive and negative arms of the spectrometer, are presented as well.

  7. Induced polarization of Λ(1116) in kaon electroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Gabrielyan, M.; Raue, B. A.; Carman, D. S.; Park, K.; Adhikari, K. P.; Adikaram, D.; Amaryan, M. J.; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Baturin, V.; Bedlinskiy, I.; Biselli, A. S.; Bono, J.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Cao, T.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D' Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Doughty, D.; Dupre, R.; El Fassi, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fleming, J. A.; Forest, T. A.; Garillon, B.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hattawy, M.; Hicks, K.; Ho, D.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Keller, D.; Khandaker, M.; Kim, W.; Klein, F. J.; Koirala, S.; Kubarovsky, V.; Kuhn, S. E.; Kuleshov, S. V.; Lenisa, P.; Levine, W. I.; Livingston, K.; MacGregor, I. J. D.; Mayer, M.; McKinnon, B.; Meyer, C. A.; Mestayer, M. D.; Mirazita, M.; Mokeev, V.; Moody, C. I.; Moutarde, H.; Movsisyan, A.; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Osipenko, M.; Pappalardo, L. L.; Paremuzyan, R.; Pasyuk, E.; Peng, P.; Phelps, W.; Phillips, J. J.; Pisano, S.; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Protopopescu, D.; Rimal, D.; Ripani, M.; Rizzo, A.; Sabatié, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Simonyan, A.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Stepanyan, S. S.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Tang, W.; Ungaro, M.; Vlassov, A. V.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Zachariou, N.; Zana, L.; Zhang, J.; Zonta, I.

    2014-09-01

    We have measured the induced polarization of the Λ(1116) in the reaction ep→e'K+Λ, detecting the scattered e' and K+ in the final state along with the proton from the decay Λ→pπ-.The present study used the CEBAF Large Acceptance Spectrometer (CLAS), which allowed for a large kinematic acceptance in invariant energy W (1.6≤W≤2.7 GeV) and covered the full range of the kaon production angle at an average momentum transfer Q2=1.90 GeV2.In this experiment a 5.50 GeV electron beam was incident upon an unpolarized liquid-hydrogen target. We have mapped out the W and kaon production angle dependencies of the induced polarization and found striking differences from photoproduction data over most of the kinematic range studied. However, we also found that the induced polarization is essentially Q2 independent in our kinematic domain, suggesting that somewhere below the Q2 covered here there must be a strong Q2 dependence. Along with previously published photo- and electroproduction cross sections and polarization observables, these data are needed for the development of models, such as effective field theories, and as input to coupled-channel analyses that can provide evidence of previously unobserved s-channel resonances.

  8. Target and beam-target spin asymmetries in exclusive pion electroproduction for Q2>1 GeV2. II. e p →e π0p

    Science.gov (United States)

    Bosted, P. E.; Kim, A.; Adhikari, K. P.; Adikaram, D.; Akbar, Z.; Amaryan, M. J.; Anefalos Pereira, S.; Avakian, H.; Badui, R. A.; Ball, J.; Balossino, I.; Battaglieri, M.; Bedlinskiy, I.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Bültmann, S.; Burkert, V. D.; Cao, T.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Chetry, T.; Ciullo, G.; Clark, L.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fanchini, E.; Fedotov, G.; Fegan, S.; Fersch, R.; Filippi, A.; Fleming, J. A.; Forest, T. A.; Fradi, A.; Ghandilyan, Y.; Gilfoyle, G. P.; Girod, F. X.; Glazier, D. I.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guler, N.; Hakobyan, H.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Harrison, N.; Hattawy, M.; Heddle, D.; Hicks, K.; Hollis, G.; Holtrop, M.; Hughes, S. M.; Ireland, D. G.; Isupov, E. L.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Keller, D.; Khachatryan, G.; Khandaker, M.; Kim, W.; Klei, A.; Klein, F. J.; Koirala, S.; Kubarovsky, V.; Kuhn, S. E.; Lanza, L.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; Mayer, M.; McCracken, M. E.; McKinnon, B.; Mineeva, T.; Mirazita, M.; Mokeev, V. I.; Montgomery, R. A.; Movsisyan, A.; Munoz Camacho, C.; Murdoch, G.; Nadel-Turonski, P.; Ni, A.; Niccolai, S.; Niculescu, G.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Phelps, W.; Pisano, S.; Pogorelko, O.; Price, J. W.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Saini, M. S.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stankovic, I.; Stepanyan, S.; Stoler, P.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Tian, Ye; Torayev, B.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Zachariou, N.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

    2017-03-01

    Beam-target double-spin asymmetries and target single-spin asymmetries were measured for the exclusive π0 electroproduction reaction γ*p →p π0 , expanding an analysis of the γ*p →n π+ reaction from the same experiment. The results were obtained from scattering of 6-GeV longitudinally polarized electrons off longitudinally polarized protons using the CEBAF Large Acceptance Spectrometer at Jefferson Laboratory. The kinematic ranges covered are 1.1 electroproduction. Reasonable agreement is found with phenomenological fits to previous data for W <1.6 GeV, but significant differences are seen at higher W . When combined with cross-sectional measurements, as well as π+ observables, the present results will provide powerful constraints on nucleon resonance amplitudes at moderate and large values of Q2, for resonances with masses as high as 2.4 GeV.

  9. Observation of Two-Source Interference in the Photoproduction Reaction AuAu -> AuAu rho(0)

    Czech Academy of Sciences Publication Activity Database

    Abelev, B. I.; Aggarwal, M. M.; Ahammed, Z.; Anderson, B. D.; Arkhipkin, D.; Averichev, G. S.; Balewski, J.; Barannikova, O.; Barnby, L. S.; Baudot, J.; Baumgart, S.; Beavis, D.R.; Bellwied, R.; Benedosso, F.; Betancourt, M.J.; Betts, R. R.; Bhasin, A.; Bhati, A.K.; Bichsel, H.; Bielčík, Jaroslav; Bielčíková, Jana; Biritz, B.; Bland, L.C.; Bombara, M.; Bonner, B. E.; Botje, M.; Bouchet, J.; Braidot, E.; Brandin, A. V.; Bruna, E.; Bueltmann, S.; Burton, T. P.; Bysterský, Michal; Cai, X.Z.; Caines, H.; Sanchez, M.C.D.; Catu, O.; Cebra, D.; Cendejas, R.; Cervantes, M.C.; Chajecki, Z.; Chaloupka, Petr; Chattopadhyay, S.; Chen, H.F.; Chen, J.H.; Cheng, J.; Cherney, M.; Chikanian, A.; Choi, K.E.; Christie, W.; Clarke, R.F.; Codrington, M.J.M.; Corliss, R.; Cormier, T.M.; Coserea, R. M.; Cramer, J. G.; Crawford, H. J.; Das, D.; Dash, S.; Daugherity, M.; De Silva, L.C.; Dedovich, T. G.; DePhillips, M.; Derevschikov, A.A.; de Souza, R.D.; Didenko, L.; Djawotho, P.; Dunlop, J.C.; Mazumdar, M.R.D.; Edwards, W.R.; Efimov, L.G.; Elhalhuli, E.; Elnimr, M.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Eun, L.; Fachini, P.; Fatemi, R.; Fedorisin, J.; Feng, A.; Filip, P.; Finch, E.; Fine, V.; Fisyak, Y.; Gagliardi, C. A.; Gaillard, L.; Ganti, M. S.; Gangaharan, D.R.; Garcia-Solis, E.J.; Geromitsos, A.; Geurts, F.; Ghazikhanian, V.; Ghosh, P.; Gorbunov, Y.N.; Gordon, A.; Grebenyuk, O.; Grosnick, D.; Grube, B.; Guertin, S.M.; Guimaraes, K.S.F.F.; Gupta, A.; Gupta, N.; Guryn, W.; Haag, B.; Hallman, T.J.; Hamed, A.; Harris, J.W.; He, W.; Heinz, M.; Heppelmann, S.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffman, A.M.; Hoffmann, G.W.; Hofman, D.J.; Hollis, R.S.; Huang, H.Z.; Humanic, T.J.; Igo, G.; Iordanova, A.; Jacobs, P.; Jacobs, W.W.; Jakl, Pavel; Jena, C.; Jin, F.; Jones, C.L.; Jones, P.G.; Joseph, J.; Judd, E.G.; Kabana, S.; Kajimoto, K.; Kang, K.; Kapitán, Jan; Keane, D.; Kechechyan, A.; Kettler, D.; Khodyrev, V.Yu.; Kikola, D.P.; Kiryluk, J.; Kisiel, A.; Klein, S.R.; Knospe, A.G.; Kocoloski, A.; Koetke, D.D.; Kopytine, M.; Korsch, W.; Kotchenda, L.; Kushpil, Vasilij; Kravtsov, P.; Kravtsov, V.I.; Krueger, K.; Krus, M.; Kuhn, C.; Kumar, L.; Kurnadi, P.; Lamont, M.A.C.; Landgraf, J.M.; LaPointe, S.; Lauret, J.; Lebedev, A.; Lednický, Richard; Lee, Ch.; Lee, J.H.; Leight, W.; LeVine, M.J.; Li, N.; Li, C.; Li, Y.; Lin, G.; Lindenbaum, S.J.; Lisa, M.A.; Liu, F.; Liu, J.; Liu, L.; Ljubicic, T.; Llope, W.J.; Longacre, R.S.; Love, W.A.; Lu, Y.; Ludlam, T.; Ma, G.L.; Ma, Y.G.; Mahapatra, D.P.; Majka, R.; Mall, O.I.; Mangotra, L.K.; Manweiler, R.; Margetis, S.; Markert, C.; Matis, H.S.; Matulenko, Yu.A.; McShane, T.S.; Meschanin, A.; Milner, R.; Minaev, N.G.; Mioduszewski, S.; Mischke, A.; Mitchell, J.; Mohanty, B.; Morozov, D.A.; Munhoz, M. G.; Nandi, B.K.; Nattrass, C.; Nayak, T. K.; Nelson, J.M.; Netrakanti, P.K.; Ng, M.J.; Nogach, L.V.; Nurushev, S.B.; Odyniec, G.; Ogawa, A.; Okada, H.; Okorokov, V.; Olson, D.; Pachr, M.; Page, B.S.; Pal, S.K.; Pandit, Y.; Panebratsev, Y.; Panitkin, S.Y.; Pawlak, T.; Peitzmann, T.; Perevoztchikov, V.; Perkins, C.; Peryt, W.; Phatak, S.C.; Poljak, N.; Poskanzer, A.M.; Potukuchi, B.V.K.S.; Prindle, D.; Pruneau, C.; Pruthi, N.K.; Putschke, J.; Raniwala, R.; Raniwala, S.; Ray, R.L.; Redwine, R.; Reed, R.; Ridiger, A.; Ritter, H.G.; Roberts, J.B.; Rogachevskiy, O.V.; Romero, J.L.; Rose, A.; Roy, C.; Ruan, L.; Russcher, M.J.; Sahoo, R.; Sakrejda, I.; Sakuma, T.; Salur, S.; Sandweiss, J.; Sarsour, M.; Schambach, J.; Scharenberg, R.P.; Schmitz, N.; Seger, J.; Selyuzhenkov, I.; Seyboth, P.; Shabetai, A.; Shahaliev, E.; Shao, M.; Sharma, M.; Shi, S.S.; Shi, X.H.; Sichtermann, E.P.; Simon, F.; Singaraju, R.N.; Skoby, M.J.; Smirnov, N.; Snellings, R.; Sorensen, P.; Sowinski, J.; Spinka, H.M.; Srivastava, B.; Stadnik, A.; Stanislaus, T.D.S.; Staszak, D.; Strikhanov, M.; Stringfellow, B.; Suaide, A.A.P.; Suarez, M.C.; Subba, N.L.; Šumbera, Michal; Sun, X.M.; Sun, Y.; Sun, Z.; Surrow, B.; Symons, T.J.M.; de Toledo, A. S.; Takahashi, J.; Tang, A.H.; Tang, Z.; Tarnowsky, T.; Thein, D.; Thomas, J.H.; Tian, J.; Timmins, A.R.; Timoshenko, S.; Tokarev, M. V.; Trainor, T.A.; Tram, V.N.; Trattner, A.L.; Trentalange, S.; Tribble, R. E.; Tsai, O.D.; Ulery, J.; Ullrich, T.; Underwood, D.G.; Van Buren, G.; van Leeuwen, M.; Vander Molen, A.M.; Vanfossen, J.A.; Varma, R.; Vasconcelos, G.S.M.; Vasilevski, I.M.; Vasiliev, A. N.; Videbaek, F.; Vigdor, S.E.; Viyogi, Y. P.; Vokal, S.; Voloshin, S.A.; Wada, M.; Walker, M.; Wang, F.; Wang, G.; Wang, J.S.; Wang, Q.; Wang, X.; Wang, X.L.; Wang, Y.; Webb, G.; Webb, J.C.; Westfall, G.D.; Whitten, C.; Wieman, H.; Wissink, S.W.; Witt, R.; Wu, Y.; Tlustý, David; Xie, W.; Xu, N.; Xu, Q.H.; Xu, Y.; Xu, Z.; Yang, P.; Yepes, P.; Yip, K.; Yoo, I.K.; Yue, Q.; Zawisza, M.; Zbroszczyk, H.; Zhan, W.; Zhang, S.; Zhang, W.M.; Zhang, X.P.; Zhang, Y.; Zhang, Z.; Zhao, Y.; Zhong, C.; Zhou, J.; Zoulkarneev, R.; Zoulkarneeva, Y.; Zuo, J.X.

    2009-01-01

    Roč. 102, č. 11 (2009), 112301/1-112301/7 ISSN 0031-9007 R&D Projects: GA MŠk LC07048; GA ČR GA202/07/0079 Institutional research plan: CEZ:AV0Z10480505; CEZ:AV0Z10100502 Keywords : heavy-ion collisions * interference * photoproduction Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 7.328, year: 2009

  10. Unified model of current-hadronic interactions. II

    International Nuclear Information System (INIS)

    Moffat, J.W.; Wright, A.C.D.

    1975-01-01

    An analytic model of current-hadronic interactions is used to make predictions which are compared with recent data for vector-meson electroproduction and for the spin density matrix of photoproduced rho 0 mesons. The rho 0 and ω electroproduction cross sections are predicted to behave differently as the mass of the virtual photon varies; the diffraction peak broadens with increasing -q 2 at fixed ν and narrows with increasing energy. The predicted rho 0 density matrix elements do not possess the approximate s-channel helicity conservation seen experimentally. The model is continued to the inclusive electron-positron annihilation region, where parameter-free predictions are given for the inclusive prosess e + + e - → p + hadrons. The annihilation structure functions are found to have nontrivial scale-invariance limits. By using total cross-section data for e + e - annihilation into hardrons, we predict the mean multiplicity for the production of nucleons

  11. Measurement of the photon electroproduction cross section at JLAB with the goal of performing a Rosenbluth separation of the DVCS contribution

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez-Arguello, Alejandro Marti [Univ. of Paris, Orsay (France). Inst. of Nuclear Physics

    2014-07-11

    The study of the inner structure of hadrons allows us to understand the nature of the interactions between partons, quarks and gluons, described by Quantum Chromodynamics. The elastic scattering reactions, which have been studied in order to measure the nucleon form factors, are included in this frame. The inelastic scattering reactions are also included in this frame, they allow us to obtain information about the nucleon structure thanks to the development of the parton distribution functions (PDFs). While through elastic scattering we can obtain information about the charge distribution of the nucleon, and hence, about the spatial distribution of the partons, through inelastic scattering we obtain information about the momentum distributions of partons, by employing the PDFs. However, we can study the exclusive inelastic scattering reactions, such as the Deeply Virtual Compton Scattering (DVCS), wich allow us to access to the spatial and momentum distributions simultaneously. This is possible thanks to the generalized parton distributions (GPDs), which allow us to correlate both types of distributions. The process known as DVCS is the easiest way to access the GPDs. This process can be expressed as the scattering of an electron by a proton by means of a virtual photon with the result of the scattered initial particles plus a real photon. We find a process competing with DVCS known as Bethe-Heitler (BH), in which the real photon is radiated by the lepton rather than the quark. Due to the small cross section of DVCS, of the order of nb, in order to conduct these kind of experiments it is necessary to make use of facilities capable of providing high beam intensities. One of these facilities is the Thomas Jefferson National Accelerator Facility , where the experiment JLab E07-007, "Complete Separation of Virtual Photon and π⁰ Electroproduction Observables of Unpolarized Protons", took place during the months of October to December of 2010. The main goal of this

  12. Gluon radiation in diffractive electroproduction

    International Nuclear Information System (INIS)

    Buchmueller, W.; McDermott, M.F.; Hebecker, A.

    1996-07-01

    Order α s -correlations to the diffractive structure functions F L D and F 2 D at large Q 2 and small x are evaluated in the semiclassical approach, where the initial proton is treated as a classical colour field. The diffractive final state contains a fast gluon in addition to a quark-antiquark pair. Two of these partons may have large transverse momentum. Our calculations lead to an intuitive picture of deep-inelastic diffractive processes which is very similar to Bjorken's aligned-jet model. Both diffractive structure functions contain leading twist contributions from high-p perpendicular to jets. (orig.)

  13. Delta Electroproduction in 12-C

    Energy Technology Data Exchange (ETDEWEB)

    McLauchlan, Steven [Univ. of Glasgow, Scotland (United Kingdom)

    2003-01-01

    The Δ-nucleus potential is a crucial element in the understanding of the nuclear system. Previous electroexcitation measurements in the delta region reported a Q2 dependence of the Δ mass indicating that this potential is dependent on the momentum of the Δ. Such a dependence is not observed for protons and neutrons in the nuclear medium. This thesis presents the experimental study of the electroexcitation of the Δ resonance in 12C, performed using the high energy electron beam at the Thomas Jefferson National Accelerator Facility, and the near 4π acceptance detector CLAS that enables the detection of the full reaction final state. Inclusive, semi inclusive, and exclusive cross sections were measured with an incident electron beam energy of 1.162GeV over the Q2 range 0.175-0.475 (GeV/c)2. A Q2 dependence of the Δ mass was only observed in the exclusive measurements indicating that the Δ-nucleus potential is affected by the momentum of the Δ.

  14. Pseudoscalar Meson Electroproduction and Transversity

    International Nuclear Information System (INIS)

    Goldstein, G.; Liuti, S.

    2011-01-01

    Exclusive meson leptoproduction from nucleons in the deeply virtual exchanged boson limit can be described by generalized parton distributions (GPDs). Including spin dependence in the description requires 8 independent quark-parton and gluon-parton functions. The chiral even subset of 4 quark-nucleon GPDs are related to nucleon form factors and to parton distribution functions. The chiral odd set of 4 quark-nucleon GPDs are related to transversity, the tensor charge, and other quantities related to transversity. Different meson or photon production processes access different combinations of GPDs. This is analyzed in terms of t-channel exchange quantum numbers, J PC and it is shown that pseudoscalar production can isolate chiral odd GPDs. There is a sensitive dependence in various cross sections and asymmetries on the tensor charge of the nucleon and other transversity parameters. In a second section, analyticity and completeness are shown to limit the partonic interpret ation of the GPDs in the ERBL region.

  15. Low Q2 kaon electroproduction

    International Nuclear Information System (INIS)

    Markowitz, P.; Acha, A.

    2010-01-01

    A measurement of the H(e, e′ K + ) reaction was performed at Hall A, TJNAF as part of the hypernuclear experiment E94-107. Data was taken at very low Q 2 (~ 0.07 (GeV/c) 2 ) and W = 2.2 GeV. Kaons were detected along the direction of q-vector, the momentum transferred by the incident electron (θ CM = 6°). These measurements provide data about the Σ 0 /Λ ratio which drops rapidly with Q 2 , the angular dependence of the cross sections as Q 2 → 0, and the dependence of the cross section with respect to Q 2 ,W and θ CM . The dependence of the cross section at very forward angles has been poorly known. Available models are inadequate to describe the results. The measurement of the elementary cross section will constrain models for the elementary reaction which are inadequate to describe these results. It is also a key ingredient in the hypernuclear spectroscopy studies performed at the same kinematics. Details of the calculations and results will be shown. (author)

  16. Production of Z{sup 0} bosons in elastic and quasi-elastic ep collisions at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Abramowicz, H. [Tel Aviv Univ. (Israel). School of Physics; Max Planck Institute for Physics, Munich (Germany); Abt, I. [Max Planck Institute for Physics, Munich (Germany); Adamczyk, L. [AGH-Univ. of Science and Technology, Krakow (Poland). Faculty of Physics and Applied Computer Science] [and others; Collaboration: ZEUS Collaboration

    2012-10-15

    The production of Z{sup 0} bosons in the reaction ep {yields} eZ{sup 0}p{sup (*)}, where p{sup (*)} stands for a proton or a low-mass nucleon resonance, has been studied in ep collisions at HERA using the ZEUS detector. The analysis is based on a data sample collected between 1996 and 2007, amounting to 496 pb{sup -1} of integrated luminosity. The Z{sup 0} was measured in the hadronic decay mode. The elasticity of the events was ensured by a cut on {eta}{sub max} < 3.0, where {eta}{sub max} is the maximum pseudorapidity of energy deposits in the calorimeter defined with respect to the proton beam direction. A signal was observed at the Z{sup 0} mass. The cross section of the reaction ep {yields} eZ{sup 0}p{sup (*)} was measured to be {sigma} (ep {yields} eZ{sup 0}p{sup (*)}) = 0.13 {+-} 0.06 (stat.) {+-} 0.01 (syst.) pb, in agreement with the Standard Model prediction of 0.16 pb. This is the first measurement of Z{sup 0} production in ep collisions.

  17. Study of the (e,e'p) quasi-elastic reaction in complex nuclei: theory and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Herraiz, Joaquin Lopez [Complutense Univ. of Madrid (Spain)

    2010-03-01

    Experimental coincidence cross section and transverse-longitudinal asymmetry ATL have been obtained for the quasielastic (e,e'p) reaction in 16O, 12C, and {sup 208}Pb in constant q-ω kinematics in the missing momentum range -350 < pmiss < 350 MeV/c. In these experiments, performed in experimental Hall A of the Thomas Jefferson National Accelerator Facility (JLAB), the beam energy and the momentum and angle of the scattered electrons were kept fixed, while the angle between the proton momentum and the momentum transfer q was varied in order to map out the missing momentum distribution. The experimental cross section and ATL asymmetry have been compared with Monte Carlo simulations based on Distorted Wave Impulse Approximation (DWIA) calculations with both relativistic and non-relativistic spinor structure. The spectroscopic factors obtained for both models are in agreement with previous experimental values, while ATL measurements favor the relativistic DWIA calculation. This thesis describes the details of the experimental setup, the calibration of the spectrometers, the techniques used in the data analysis to derive the final cross sections and the ATL, the ingredients of the theoretical calculations employed and the comparison of the results with the simulations based on these theoretical models.

  18. Contribution to the study of heavy-ion induced quasi-elastic processes in the 2s-1d shell

    International Nuclear Information System (INIS)

    Greiner, A.

    1982-06-01

    In the first part of this thesis, we present a study of the charge exchange reaction 28 Si( 18 O, 18 F) 28 Al at 56 MeV. This reaction can be easily understood in terms of a one-step direct charge exchange mechanism. With a very simple shell model, it can be interpreted that a neutron of the 18 O in the Jsup(π)=0 + , T=1 state interacts with a proton in the dsub(5/2) shell of 28 Si and they exchange their spin and charge forming Jsup(π)=1 + , T=0 18 F, and Jsup(π)=3 + or 2 + , T=1 28 Al. In the present analysis of data, we have first performed the direct charge exchange DWBA calculations. These results are compared with the exact-finite-range (EFR) second order DWBA calculations which take into account the successive one-nucleon stripping and pickup, and pickup and stripping process. In the second part, we wish to report results and analysis concerning the 24 Mg+ 12 C system. The 180 0 c.m. angle scattering excitation functions were measured between 12- and 27-MeV c.m. corresponding to a range in the compound 36 Ar excitation energy of 28.3 to 43.3 MeV. Several angular distributions for the elastic and inelastic scattering have been measured on the top of the bumps of the elastic scattering excitation function. These elastic scattering angular distributions cannot be fitted by a single squared Legendre polynomial of order L. A complete phase shift analysis is presented. We discuss also the shapes of the first 24 Mg 2 + inelastic scattering angular distributions with respect to the shape of the elastic scattering differential cross section [fr

  19. Applications of the quasi-elastic light scattering to the study of dynamic properties of charged macro-molecules

    International Nuclear Information System (INIS)

    Gouesin-Menez, Renee

    1979-01-01

    The object of this research thesis is to study the modifications of dynamic properties of a macromolecule under the influence of variations of its medium, by using a frequency analysis of the spectrum of light scattered by a solution of particles. Thus, an important part of this thesis addresses the study and development of the scattering method and of its analysis by 'photon pulses', and the development and adjustment of an electrophoretic device to study light scattering by molecules submitted to an electric field. Then, hydrodynamic characteristics of some macromolecules have been measured with or without electric field. The studied molecular systems have been: calibrated spheres of latex polystyrene, a globular protein (bovine serum albumin), a polysaccharide (under the form of a rigid short stick), a flexible linear polyelectrolyte (polymethacrylate), and two DNA samples

  20. Quasi elastic scattering of 600 MeV protons by alpha clusters in light and medium nuclei

    International Nuclear Information System (INIS)

    Landaud, G.; Devaux, A.; Delpierre, P.; Kahane, J.; Sene, R.; Yonnet, J.; Anne, R.

    1977-06-01

    Knockout of α-clusters from light and medium weight nuclei by 600 MeV protons has been investigated. The outgoing protons and α-particles were detected in coincidence; their momenta were measured with two large magnetic spectrometers with proportional wire chambers. Experimental methods used to work with a high beam rate and an efficient proton rejection in the α-arm are described. Separation energy spectra are given for 6 Li, 7 Li, 12 C, 24 Mg, 27 Al and 40 Ca nuclei. A peak is observed at an excited energy equal to zero, except for the 27 Al target

  1. Coupled channel effects in quasi-elastic barrier distributions of 16,18O + 206Pb systems

    International Nuclear Information System (INIS)

    Jha, V.; Roy, B.J.; Parkar, V.V.; Kumawat, H.; Pal, U.K.; Pandit, S.K.; Mahata, K.; Shrivastava, A.; Mohanty, A.K.

    2013-01-01

    The fusion barrier distribution and QEBD for the 16 O + 208 Pb have been studied in great detail. The couplings due to the collective excitations of the colliding nuclei are found to have the dominant effect as deduced by the conventional coupled-channels calculations used to explain the experimental QEBD and fusion barrier distributions. In contrast, for the 18 O + 206 Pb system, the role of single neutron stripping (Q-value= -1.308 MeV) and neutron pair transfer (Q-value = + 1.917 MeV) are expected to be significant. In the present work, the QEBD measurements for the 18 O + 206 Pb system are performed for the investigation of these aspects

  2. (Quasi)Elastic Electron-Muon Large-Angle Scattering to a Two-Loop Approximation: Vertex Contributions

    CERN Document Server

    Bytev, V V; Shaikhatdenov, B G

    2002-01-01

    We consider a process of quasielastic e\\mu large-angle scattering at high energies with radiative corrections up to a two-loop level. The lowest order radiative correction arising both from one-loop virtual photon emission and a real soft emission are presented to a power accuracy. Two-loop level corrections are supposed to be of three gauge-invariant classes. One of them, so-called vertex contribution, is given in logarithmic approximation. Relation with the renormalization group approach is discussed.

  3. (Quasi)Elastic Electron-Muon Large-Angle Scattering to a Two-Loop Approximation Vertex Contributions

    CERN Document Server

    Bytev, V V; Shaikhatdenov, B G

    2002-01-01

    We consider a process of quasielastic e\\mu large-angle scattering at high energies with radiative corrections up to a two-loop level. The lowest order radiative correction arising both from one-loop virtual photon emission and a real soft emission are presented to a power accuracy. Two-loop level corrections are supposed to be of three gauge-invariant classes. One of them, so-called vertex contribution, is given in logarithmic approximation. Relation with the renormalization group approach is discussed.

  4. Wigner-Kirkwood expansion of the quasi-elastic nuclear responses and application to spin-isospin responses

    International Nuclear Information System (INIS)

    Chanfray, G.

    1988-01-01

    We derive a semi-classical Wigner-Kirkwood expansion (Planck constant expansion) of the linear response functions. We find that the semi-classical results compare very well to the quantum mechanical calculations. We apply our formalism to the spin-isospin responses and show that surface-peaked Planck constant 2 corrections considerably decrease the ratio longitudinal/transverse as obtained through the Los Alamos (longitudinal momentum) experiment

  5. Exclusive π0 electroproduction at W>2  GeV with CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Bedlinskiy, I.; Kubarovsky, V.; Niccolai, S.; Stoler, P.; Adhikari, K. P.; Anderson, M. D.; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Biselli, A. S.; Boiarinov, S.; Bono, J.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D' Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Doughty, D.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fleming, J. A.; Forest, T. A.; Garillon, B.; Garçon, M.; Gavalian, G.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guegan, B.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Harrison, N.; Hattawy, M.; Hicks, K.; Holtrop, M.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jo, H. S.; Joo, K.; Keller, D.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Koirala, S.; Kuhn, S. E.; Kuleshov, S. V.; Lenisa, P.; Levine, W. I.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; Mayer, M.; McKinnon, B.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Moody, C. I.; Moutarde, H.; Movsisyan, A.; Munoz Camacho, C.; Nadel-Turonski, P.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Pappalardo, L. L.; Park, K.; Park, S.; Pasyuk, E.; Phelps, E.; Phelps, W.; Phillips, J. J.; Pisano, S.; Pogorelko, O.; Price, J. W.; Prok, Y.; Protopopescu, D.; Procureur, S.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Ritchie, B. G.; Rizzo, A.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Senderovich, I.; Sharabian, Y. G.; Simonyan, A.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Stepanyan, S. S.; Strauch, S.; Sytnik, V.; Tang, W.; Tian, Ye; Ungaro, M.; Vlassov, A. V.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D.; Wei, X.; Weinstein, L. B.; Yurov, M.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.

    2014-08-01

    Exclusive neutral-pion electroproduction (ep -> e'p'pi(0)) was measured at Jefferson Lab with a 5.75-GeV electron beam and the CLAS detector. Differential cross sections d(4)sigma/dtdQ(2)dx(B)d phi(pi) and structure functions sigma(T) + sigma(L), sigma(TT), and sigma(LT) as functions of t were obtained over a wide range of Q(2) and x(B). The data are compared with Regge and handbag theoretical calculations. Analyses in both frameworks find that a large dominance of transverse processes is necessary to explain the experimental results. For the Regge analysis it is found that the inclusion of vector meson rescattering processes is necessary to bring the magnitude of the calculated and measured structure functions into rough agreement. In the handbag framework, there are two independent calculations, both of which appear to roughly explain the magnitude of the structure functions in terms of transversity generalized parton distributions.

  6. Target and beam-target spin asymmetries in exclusive pion electroproduction for Q2>1 GeV2 . I. e p →e π+n

    Science.gov (United States)

    Bosted, P. E.; Amaryan, M. J.; Anefalos Pereira, S.; Avakian, H.; Badui, R. A.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Briscoe, W. J.; Bültmann, S.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Ciullo, G.; Clark, L.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; De Vita, R.; Deur, A.; De Sanctis, E.; Djalali, C.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fanchini, E.; Fedotov, G.; Filippi, A.; Fleming, J. A.; Forest, T.; Fradi, A.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Girod, F. X.; Gleason, C.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Hakobyan, H.; Hattawy, M.; Hicks, K.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jiang, H.; Jo, H. S.; Joo, K.; Joosten, S.; Khachatryan, G.; Khandaker, M.; Kim, A.; Kim, W.; Klein, F. J.; Koirala, S.; Kubarovsky, V.; Kuhn, S. E.; Lanza, L.; Net, L. A.; Lenisa, P.; Livingston, K.; MacGregor, I. J. D.; McCracken, M. E.; McKinnon, B.; Meyer, C. A.; Mirazita, M.; Mokeev, V. I.; Montgomery, R. A.; Munevar, E.; Munoz Camacho, C.; Murdoch, G.; Nadel-Turonski, P.; Niccolai, S.; Osipenko, M.; Ostrovidov, A. I.; Park, K.; Pasyuk, E.; Peng, P.; Phelps, W.; Pisano, S.; Pogorelko, O.; Price, J. W.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rosner, G.; Rossi, P.; Schumacher, R. A.; Seder, E.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stankovic, I.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Tian, Ye; Torayev, B.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Wei, X.; Weinstein, L. B.; Zachariou, N.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

    2017-03-01

    Beam-target double-spin asymmetries and target single-spin asymmetries were measured for the exclusive π+ electroproduction reaction γ*p →n π+ . The results were obtained from scattering of 6-GeV longitudinally polarized electrons off longitudinally polarized protons using the CEBAF Large Acceptance Spectrometer at Jefferson Laboratory. The kinematic range covered is 1.1

  7. Coherent diffractive photoproduction of rho(0) mesons on gold nuclei at 200 GeV/nucleon-pair at the Relativistic Heavy Ion Collider

    Czech Academy of Sciences Publication Activity Database

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Bielčík, J.; Bielčíková, Jana; Chaloupka, P.; Federič, Pavol; Federičová, P.; Harlenderová, A.; Kocmánek, Martin; Kvapil, J.; Lidrych, J.; Rusňák, Jan; Rusňáková, O.; Šaur, Miroslav; Šimko, Miroslav; Šumbera, Michal; Trzeciak, B. A.

    2017-01-01

    Roč. 96, č. 5 (2017), č. článku 054904. ISSN 2469-9985 R&D Projects: GA MŠk LM2015054; GA MŠk LG15001 Institutional support: RVO:61389005 Keywords : STAR collaboration * LHC Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders OBOR OECD: Nuclear physics Impact factor: 3.820, year: 2016

  8. rho(0) production and possible modification in Au+Au and p+p collisions at root S-NN=200 GeV

    Czech Academy of Sciences Publication Activity Database

    Adams, J.; Adler, C.; Chaloupka, Petr; Filip, P.; Lednický, R.; Šumbera, Michal

    2004-01-01

    Roč. 92, č. 9 (2004), 092301 ISSN 0031-9007 R&D Projects: GA ČR GA202/04/0793 Institutional research plan: CEZ:AV0Z1048901 Keywords : vector-mesons production * 205 GEV-C * inclusive production Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 7.218, year: 2004

  9. Role of vector mesons in pion electroproduction

    International Nuclear Information System (INIS)

    Uleshchenko, V.V.

    2007-01-01

    The talk is concerned with mechanisms of pion production in deeply inelastic scattering related to the interaction of virtual photon with the nucleon via an intermediate vector-meson state of the probe. A clear evidence of these mechanisms in the HERMES experimental data is revealed

  10. Spectroscopy of Li-9(Lambda) by electroproduction

    Czech Academy of Sciences Publication Activity Database

    Urciuoli, G. M.; Cusanno, F.; Marrone, S.; Acha, A.; Baturin, P.; Bydžovský, Petr; Deur, A. P.; Ferdi, C.; Garibaldi, F.; Hansen, J. O.

    2015-01-01

    Roč. 91, č. 3 (2015), 034308 ISSN 0556-2813 R&D Projects: GA ČR(CZ) GAP203/12/2126 Institutional support: RVO:61389005 Keywords : hypernuclei * cross section * Jefferson Lab Hall A Collaboration Subject RIV: BE - Theoretical Physics Impact factor: 3.146, year: 2015

  11. N*(1535) electroproduction at high Q2

    Energy Technology Data Exchange (ETDEWEB)

    G. Ramalho, M.T. Pena, K. Tsushima

    2012-04-01

    A covariant spectator quark model is applied to study the {gamma}N {yields} N*(1535) reaction in the large Q{sup 2} region. Starting from the relation between the nucleon and N*(1535) systems, the N*(1535) valence quark wave function is determined without the addition of any parameters. The model is then used to calculate the {gamma}N {yields} N*(1535) transition form factors. A very interesting, useful relation between the A{sub 1/2} and S{sub 1/2} helicity amplitudes for Q{sup 2} > GeV{sup 2}, is also derived.

  12. Electroproduction of polarized Λ's

    International Nuclear Information System (INIS)

    Kunne, R.A.

    1992-01-01

    Lambdas are a powerful tool to explore spin effects of QCD. The λ polarization is self analyzing, as it is measurable from the angular distribution of the decay products. Two applications of polarized electroproduced λ's are suggested: the measurement of λ polarization at large transverse momentum as a possible test of QCD and the measurement of transversely polarized parton distributions

  13. Inclusive electroproduction in quantum field theory

    International Nuclear Information System (INIS)

    Galfi, L.

    1978-01-01

    It is shown that starting from the quark-pseudoscalar gluon interacting Lagrangian the diagrammatic approach leads to parton picture for the process e+p→e+h+X. The scaling behaviour of certain structure functions is investigated in different kinematic regions

  14. Electroproduction of Kaons on light nuclei

    International Nuclear Information System (INIS)

    Zeidman, B.; Abbott, D.; Ahmidouch, A.; Ambrozewicz, P.; Armstrong, C. S.; Arrington, J.; Bailey, K.; Cummings, W. J.; Dohrmann, F.; Gao, H.; Geesaman, D. F.; Hafidi, K.; Hansen, J. O.; Jackson, H. E.; Mueller, B.; O'Neill, T. G.; Potterveld, D.; Reimer, P. E.; Reinhold, J.; Schiffer, J. P.

    2000-01-01

    The A(e,eprimeK + )YX reaction on H, D, 3 He, and 4 He was investigated in Hall C at CEBAF. Data were obtained for Q 2 ∼ 0.35 and 0.5 GeV 2 at 3.245 GeV. The missing mass spectra for both H and D are fitted with Monte-Carlo simulations incorporating peaks corresponding to Λ production on the proton and Σ production on both the proton and neutron. For D, the cross section ratio Σ 0 /Σ - ∼ 2, and excess yield close to the thresholds for Λ and Σ production can be attributed to final-state interactions that are compared to the data. The analysis of the data for the He targets is in a more preliminary state with broader quasi-free peaks resulting from the higher Fermi momenta. Evidence for bound Λ-hypernuclear states is seen and other structure may be present

  15. Pion photo- and electroproduction on light nuclei

    International Nuclear Information System (INIS)

    Laget, J.M.

    1983-05-01

    The mechanisms which govern the absorption of a virtual or real photon by a nucleus at intermediate energy are presented. The method of analysis is based on the non relativistic reduction of a few relevant diagrams. Comparison of it to more conventional approaches, and estimation of its limits are shown. It is particularly well suited to the study of the few body systems

  16. π+-electroproduction above the resonance region

    International Nuclear Information System (INIS)

    Brauel, P.; Canzler, T.; Cords, D.; Felst, R.; Grindhammer, G.; Helm, M.; Kollmann, W.D.; Krehbiel, H.; Schaedlich, M.

    1976-07-01

    The reaction e + p → e' + n + π + was studied detecting e' and π + in coincidence at an invariant hadronic mass of 2.19 GeV. The measurements were performed at electron four-momentum transfers squared of Q 2 = 0.06, 0.28, 0.70 and 1.35 GeV 2 . The differential cross section was found to be roughly independent of Q 2 for Q 2 > 0.7 GeV 2 and abs. t abs. > 0.2 GeV 2 . (orig.) [de

  17. Electroproduction of kaons on light nuclei

    International Nuclear Information System (INIS)

    B. Zeidman; D. Abbott; A. Ahmidouch; P. Ambrozewicz; C. S. Armstrong; J. Arrington; R. Asaturyan; K. Assamagan; S. Avery; K. Bailey; O. K. Baker; S. Beedoe; H. Bitao; H. Breuer; D. S. Brown; R. Carlini; J. Cha; N. Chant; E. Christy; A. Cochran; L. Cole; G. Collins; C. Cothran; J. Crowder; W. J. Cummings; S. Danagoulian; F. Dohrmann; F. Duncan; J. Dunne; D. Dutta; T. Eden; M. Elaasar; R. Ent; L. Ewell; H. Fenker; H. T. Fortune; Y. Fujii; L. Gan; H. Gao; K. Garrow; D. F. Geesaman; P. Gueye; K. Gustafsson; K. Hafidi; J. O. Hansen; W. Hinton; H. E. Jackson; H. Juengst; C. Keppel; A. Klein; D. Koltenuk; Y. Liang; J. H. Liu; A. Lung; D. Mack; R. Madey; P. Markowitz; C. J. Martoff; D. Meekins; J. Mitchell; T. Miyoshi; H. Mkrtchyan; R. Mohring; S. K. Mtingwa; B. Mueller; T. G. O'Neill; G. Niculescu; I. Niculescu; D. Potterveld; J. W. Price; B. A. Raue; P. E. Reimer; J. Reinhold; J. Roche; P. Roos; M. Sarsour; Y. Sato; G. Savage; R. Sawafta; J. P. Schiffer; R. E. Segel; A. Semenov; S. Stepanyan; V. Tadevosian; S. Tajima; L. Tang; B. Terburg; A. Uzzle; S. Wood; H. Yamaguchi; C. Yan; C. Yan; L. Yuan; M. Zeier; B. Zihlmann

    2001-01-01

    The A(e,eiK+)YX reaction on H, D, 3 He, and 4 He was investigated in Hall C at CEBAF. Data were obtained for Q 2 ∼ 0.35 and 0.5 GeV 2 at 3.245 GeV. The missing mass spectra for both H and D are fitted with Monte-Carlo simulations incorporating peaks corresponding to Lambda production on the proton and Sigma production on both the proton and neutron. For D, the cross section ratio Sigma 0 /Sigma - ∼ 2, and excess yield close to the thresholds for Lambda and Sigma production can be attributed to final-state interactions; models are compared to the data. The analysis of the data for the He targets is in a more preliminary state with broader quasi-free peaks resulting from the higher Fermi momenta. Evidence for bound Lambda-hypernuclear states is seen and other structure may be present

  18. Investigation of mean energy losses in quasi-elastic 3Hp scattering at 2'5 GeV/c tritium momentum

    International Nuclear Information System (INIS)

    Blinov, A.V.; Chuvilo, I.V.; Ergakov, V.A.

    1983-01-01

    The mean energy losses of fast protons in reaction p+sup(3)H→Psub(F)+X were investigated using the 80 cm liquid hydrogen bubble chamber exposed to a 2.5 GeV/c tritium beam. The experimental results are compared with the predictions based on the sum rule for energy losses which are valid in the multiple scattering theory when the completeness condition for the excited nucleus wave functions is combined with the locality of the nuclear potential

  19. Li-ion conduction in the LiBH4:LiI system from Density Functional Theory calculations and Quasi-Elastic Neutron Scattering

    DEFF Research Database (Denmark)

    Myrdal, Jon Steinar Gardarsson; Blanchard, Didier; Sveinbjörnsson, Dadi Þorsteinn

    2013-01-01

    The hexagonal high-temperature polymorph of LiBH4 is stabilized by solid solution with LiI to exhibit superionic Li+ ionic conductivity at room temperature. Herein, the mechanisms for the Li+ diffusion are investigated for the first time by density functional theory (DFT) calculations coupled...

  20. Jefferson Lab E89-044 experiment: study of the quasi-elastic He3(e,e'p)d reaction in parallel kinematics

    International Nuclear Information System (INIS)

    Penel-Nottaris, E.

    2004-07-01

    The Jefferson Lab Hall A E89-044 experiment has measured the He 3 (e,e'p) reaction cross-sections. The extraction of the longitudinal and transverse response functions for the two-body break-up He 3 (e,e'p)d reaction in parallel kinematics allows the study of the bound proton electromagnetic properties inside the He 3 nucleus and the involved nuclear mechanisms beyond plane waves approximations, for missing momenta of 0 and +- 300 MeV/c and transferred momenta from 0.8 to 4.1 GeV 2 . Preliminary cross-sections have been obtained after calibration of the experimental setup by fitting theoretical models averaged over the experimental phase-space using a Monte-Carlo simulation. The 8% systematic error on cross-sections is linked mainly to the absolute normalization of the target density: the elastic scattering data analysis will allow to reduce this error. The preliminary results show some disagreement with theoretical predictions for the forward angles kinematics around 0 MeV/c missing momenta and sensitivity to final state interactions and He 3 waves functions for missing momenta of 300 MeV/c. The longitudinal and transverse separation should constraint theoretical models more strongly. (author)

  1. Proton quasi-elastic scattering at 600MeV on the. cap alpha. -substructure of medium nuclei. [Differential cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Anne, R [CEA Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Service d' Entretien et de Developpement des Appareils de Physique; Delpierre, P; Kahane, J; Sene, R [College de France, 75 - Paris. Lab. de Physique Corpusculaire; Devaux, A; Landaud, G [Clermont-Ferrand Univ., 63 (France); Yonnet, J [Caen Univ., 14 (France). Lab. de Physique Corpusculaire

    1975-01-01

    Alpha knock out from light and medium nuclei up to /sup 40/Ca was investigated. Preliminary values of the differential cross sections are given for /sup 6/Li and /sup 12/C nuclei. The p(R) recoil momentum distributions show a maximum at p(R)=0.

  2. The transition between quasi elastic and completely damped collisions studied in the 40Ar(280 MeV)+58Ni reaction

    International Nuclear Information System (INIS)

    Galin, J.; Gatty, B.; Guerreau, D.; Lefort, M.; Tarrago, X.; Babinet, R.; Cauvin, B.; Girard, J.; Nifenecker, H.

    1976-01-01

    A carefull exploration of the angular distribution for the products emitted mainly below the grazing angle shows the continuous evolution from Q.E. to completely damped collisions. The relative relaxation time of the collective degrees of freedom is considered. (orig.) [de

  3. Target and beam-target spin asymmetries in exclusive π+ and π- electroproduction with 1.6- to 5.7-GeV electrons

    Energy Technology Data Exchange (ETDEWEB)

    Bosted, P. E.; Biselli, A. S.; Careccia, S.; Dodge, G.; Fersch, R.; Guler, N.; Kuhn, S. E.; Pierce, J.; Prok, Y.; Zheng, X.; Adhikari, K. P.; Adikaram, D.; Akbar, Z.; Amaryan, M. J.; Anefalos Pereira, S.; Asryan, G.; Avakian, H.; Badui, R. A.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Boiarinov, S.; Briscoe, W. J.; Bültmann, S.; Burkert, V. D.; Cao, T.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Chetry, T.; Ciullo, G.; Clark, L.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D' Angelo, A.; Dashyan, N.; De Vita, R.; Deur, A.; Djalali, C.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Eugenio, P.; Fanchini, E.; Fedotov, G.; Filippi, A.; Fleming, J. A.; Forest, T. A.; Fradi, A.; Garçon, M.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gleason, C.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guo, L.; Hafidi, K.; Hanretty, C.; Harrison, N.; Hattawy, M.; Heddle, D.; Hicks, K.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Joosten, S.; Keller, D.; Khandaker, M.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuleshov, S. V.; Lanza, L.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; McCracken, M. E.; McKinnon, B.; Meyer, C. A.; Minehart, R.; Mirazita, M.; Mokeev, V.; Movsisyan, A.; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Net, L. A.; Ni, A.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Peng, P.; Phelps, W.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Simonyan, A.; Skorodumina, Iu.; Smith, G. D.; Sparveris, N.; Stankovic, Ivana; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Taiuti, M.; Tian, Ye; Torayev, B.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.

    2016-11-01

    Beam-target double-spin asymmetries and target single-spin asymmetries in exclusive pi(+) and quasiexclusive pi(-) electroproduction were obtained from scattering of 1.6- to 5.7-GeV longitudinally polarized electrons from longitudinally polarized protons (for pi(+)) and deuterons (for pi(-)) using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The kinematic range covered is 1.1 < W < 2.6 GeV and 0.05 < Q(2) < 5 GeV2, with good angular coverage in the forward hemisphere. The asymmetry results were divided into approximately 40 000 kinematic bins for pi(+) from free protons and 15 000 bins for pi(-) production from bound nucleons in the deuteron. The present results are found to be in reasonable agreement with fits to previous world data for W < 1.7 GeV and Q(2) < 0.5 GeV2, with discrepancies increasing at higher values of Q(2), especially for W > 1.5 GeV. Very large target-spin asymmetries are observed for W > 1.6 GeV. When combined with cross-section measurements, the present results can provide powerful constraints on nucleon resonance amplitudes at moderate and large values of Q(2), for resonances with masses as high as 2.3 GeV.

  4. Beam spin asymmetry in deep and exclusive pi0 electroproduction

    International Nuclear Information System (INIS)

    R. De Masi

    2007-01-01

    The beam spin asymmetry (BSA) in the exclusive reaction ep->ep pi0 was measured with the CEBAF 5.77 GeV polarized electron beam and Large Acceptance Spectrometer(CLAS). The xB, Q2, t and phi dependences of the pi0 BSA are presented in the deep inelastic regime. The asymmetries are fitted with a sin(phi) function and their amplitudes are extracted. Overall, they are of the order of 0.04 - 0.11 and roughly independent of t. This is the signature of a non-zero longitudinal-transverse interference. The implications concerning the applicability of a formalism based on generalized parton distributions, as well as the extension of a Regge formalism at high photon virtualities, are discussed

  5. Light cone sum rules for single-pion electroproduction

    International Nuclear Information System (INIS)

    Mallik, S.

    1978-01-01

    Light cone dispersion sum rules (of low energy and superconvergence types) are derived for nucleon matrix elements of the commutator involving electromagnetic and divergence of axial vector currents. The superconvergence type sum rules in the fixed mass limit are rewritten without requiring the knowledge of Regge subtractions. The retarded scaling functions occurring in these sum rules are evaluated within the framework of quark light cone algebra of currents. Besides a general consistency check of the framework underlying the derivation, the author infers, on the basis of crude evaluation of scaling functions, an upper limit of 100 MeV for the bare mass of nonstrange quarks. (Auth.)

  6. Nonpartonic Effects in Pion Electroproduction in the Hermes Kinematical Region

    International Nuclear Information System (INIS)

    Uleshchenko, V.; Szczurek, A.

    2002-01-01

    The presentation is concerned with higher twist corrections of nonpartonic origin to semi-inclusive observables in the kinematical region relevant for the HERMES experiment. We demonstrate a strong impact of the VDM-like interaction and the exclusive production of ρ 0 meson on the extraction of the (anti)d - (anti)u asymmetry from charged pion DIS multiplicities. We also show that it is the exclusive- ρ 0 channel which accounts for the experimentally observed effect of the excess of charged over neutral pions produced at large z. (author)

  7. Electroproduction of pairs at beam-beam collision

    International Nuclear Information System (INIS)

    Bajer, V.N.; Katkov, V.M.; Strakhovenko, V.M.

    1989-01-01

    Charged particle pair production at beam-beam collision in electron-positron linear colliders has been discussed taking into account a finite size of the beams (both longitudinal and transverse) and end effects. Contributions of the main acting mechanisms are singled out which depend on the energy of initial particles and the masses of created particles. A spectral distribution of produced particles is presented. 15 refs

  8. High Resolution Spectroscopy of 16N#Lambda# by Electroproduction

    International Nuclear Information System (INIS)

    Cusanno, Francesco; Urciuoli, Guido; Acha Quimper, Armando; Ambrozewicz, Pawel; Aniol, Konrad; Baturin, Pavlo; Bertin, Pierre; Benaoum, Hachemi; Blomqvist, Ingvar; Boeglin, Werner; Breuer, Herbert; Brindza, Paul; Bydzovsky, Petr; Camsonne, Alexandre; Chang, C.; Chang, C.C.; Chen, Jian-Ping; Choi, Seonho; Chudakov, Eugene; Cisbani, Evaristo; Colilli, Stefano; Coman, Luminita; Craver, Brandon; de Cataldo, Giacinto; De Jager, Cornelis; De Leo, Raffaele; Deur, Alexandre; Ferdi, Catherine; Feuerbach, Robert; Folts, Edward; Frullani, Salvatore; Garibaldi, Franco; Gayou, Olivier; Giuliani, Fausto; Gomez, Javier; Gricia, Massimo; Hansen, Jens-Ole; Hayes, David; Higinbotham, Douglas; Holmstrom, Timothy; Hyde, Charles; Ibrahim, Hassan; Iodice, Mauro; Jiang, Xiaodong; Kaufman, Lisa; Kino, Kouichi; Kross, Brian; Lagamba, Luigi; LeRose, John; Lindgren, Richard; Lucentini, Maurizio; Margaziotis, Demetrius; Markowitz, Pete; Marrone, Stefano; Meziani, Zein-Eddine; McCormick, Kathy; Michaels, Robert; Millener, D.; Miyoshi, Toshinobu; Moffit, Bryan; Monaghan, Peter; Moteabbed, Maryam; Munoz Camacho, Carlos; Nanda, Sirish; Nappi, E.; Nelyubin, Vladimir; Norum, Blaine; Okasyasu, Y.; Paschke, Kent; Perdrisat, Charles; Piasetzky, Eliazer; Punjabi, Vina; Qiang, Yi; Raue, Brian; Reimer, Paul; Reinhold, Joerg; Reitz, Bodo; Roche, Rikki; Rodriguez, Victor; Saha, Arunava; Santavenere, Fabio; Sarty, Adam; Segal, John; Shahinyan, Albert; Singh, Jaideep; Sirca, Simon; Snyder, Ryan; Solvignon, Patricia; Sotona, M.; Sotona, Miloslav; Subedi, Ramesh; Sulkosky, Vince; Sulkosky, Vincent; Suzuki, Tomokazu; Ueno, Hiroaki; Ulmer, Paul; Veneroni, P.P.; Voutier, Eric; Wojtsekhowski, Bogdan; Zeng, X.; Zorn, Carl

    2009-01-01

    An experimental study of the 16O(e, e'K+)16N # Lambda# reaction has been performed at Jefferson Lab. A thin film of falling water was used as a target. This permitted a simultaneous measurement of the p(e, e'K+)Λ,Σ 0 exclusive reactions and a precise calibration of the energy scale. A ground-state binding energy of 13.76 ± 0.16 MeV was obtained for 16N # Lambda# with better precision than previous measurements on the mirror hypernucleus 16O # Lambda#. Precise energies have been determined for peaks arising from a Lambda in s and p orbits coupled to the p1/2 and p3/2 hole states of the 15N core nucleus.

  9. Lambda polarization in association K+ -Lambda electro-production

    CERN Document Server

    Teodorescu, L; Angelescu, T; Baker, O K; Ent, R; Guidal, M; Laget, J M; Mitchell, J; Niculescu, G; Vanderhaeghen, V; William, R

    1999-01-01

    The result of a feasibility study to measure the Lambda polarization in associated K+ -Lambda electro production is presented. This measurement was performed in the experimental Hall C at Jefferson Lab. The scattered electron was detected in the HMS spectrometer, and the electro-produced kaon and the proton from the Lambda -> ppi- decay were both detected in the SOS spectrometer. This quantity is very sensitive to the elementary p(e,e'K) [capital Lambda, Greek] process and gives information on resonance production, and Regge exchange, among others. The result presented was measured at Q2=1.50 (GeV/c)2 and cos [straight theta, small theta, Greek] K [small gamma, Greek] CM=14 sup o. The limits of the [capital Lambda, Greek] polarization, with respect to the p [small gamma, Greek] x pK axis, were found to be -0.21 and +0.89 with a confidence level of 68%. The result is compared to theoretical predictions based on an effective hadronic field Lagrangian model and a Regge framework model.

  10. On the inclusive electroproduction of new particles and multimuon events

    International Nuclear Information System (INIS)

    Gerasimov, S.B.

    1977-01-01

    Some experimental tests are proposed for excitation of the hadron coloured degrees of freedom and for internal and spatial symmetries in the μN deep inelastic scattering generating multimuon states. The importance is stressed of separation of the observed cross-section into the longitudinal and transversal part for checking the coloured gluon production and dynamical implication of new mass scale related to 'heavy' partons inside nucleons

  11. High -Resolution Spectroscopy of N-16 by Electroproduction

    Czech Academy of Sciences Publication Activity Database

    Cusanno, F.; Urciuoli, G.M.; Acha, A.; Ambrozewicz, P.; Aniol, K.A.; Baturin, P.; Bertin, P.Y.; Benaoum, H.; Blomqvist, K.I.; Boeglin, W.U.; Breuer, H.; Brindza, P.; Bydžovský, Petr; Camsonne, A.; Chang, C.C.; Chen, J.P.; Choi, S.; Chudakov, E.A.; Cisbani, E.; Colilli, S.; Coman, L.; Craver, B.J.; De Cataldo, G.; de Jager, C.W.; De Leo, R.; Deur, A. P.; Ferdi, C.; Feuerbach, R. J.; Folts, E.; Fratoni, R.; Frullani, S.; Garibaldi, F.; Gayou, O.; Giuliani, F.; Gomez, J.; Gricia, M.; Hansen, J. O.; Hayes, D.; Higinbotham, D. W.; Holmstrom, T.K.; Hyde, C.E.; Ibrahim, H.F.; Iodice, M.; Jiang, X.; Kaufman, L.J.; Kino, K.; Kross, B.; Lagamba, L.; Le Rose, J.J.; Lindgren, R.A.; Lucentini, M.; Margaziotis, D.J.; Markowitz, P.; Marrone, S.; Meziani, Z.E.; McCormick, K. D.; Michaels, R.W.; Millener, D.J.; Miyoshi, T.; Moffit, B.; Monaghan, P.A.; Moteabbed, M.; Munoz Camacho, C.; Nanda, S.; Nappi, E.; Nelyubin, V.V.; Norum, B.E.; Okayasu, Y.; Paschke, K.D.; Perdrisat, C.F.; Piasetzky, E.; Punjabi, V.A.; Qiang, Y.; Raue, B.; Reimer, P.E.; Reinhold, J.; Reitz, B.; Roche, R.E.; Rodriguez, V.M.; Saha, A.; Santavenere, F.; Sarty, A.J.; Segal, J.; Shahinyan, A.; Singh, J.; Širca, S.; Snyder, R.; Solvignon, P.H.; Sotona, Miloslav; Subedi, R.; Sulkosky, V.A.; Suzuki, T.; Ueno, H.; Ulmer, P.E.; Veneroni, P.; Voutier, E.; Wojtsekhowski, B.B.; Zheng, X.; Zorn, C.

    2009-01-01

    Roč. 103, č. 20 (2009), 202501/1-202501/5 ISSN 0031-9007 R&D Projects: GA ČR GA202/08/0984 Institutional research plan: CEZ:AV0Z10480505 Keywords : MeV Subject RIV: BE - Theoretical Physics Impact factor: 7.328, year: 2009

  12. The dipole representation of vector meson electroproduction beyond leading twist

    Energy Technology Data Exchange (ETDEWEB)

    Besse, A. [LPT, Universite Paris-Sud, CNRS, 91405, Orsay (France); Szymanowski, L. [National Center for Nuclear Research (NCBJ), Warsaw (Poland); Wallon, S., E-mail: wallon@th.u-psud.fr [LPT, Universite Paris-Sud, CNRS, 91405, Orsay (France); UPMC Univ. Paris 06, Faculte de Physique, 4 place Jussieu, 75252 Paris Cedex 05 (France)

    2013-02-01

    We link the recent computation beyond leading twist of the impact factor of the transition {gamma}{sub T}{sup Low-Asterisk }{yields}{rho}{sub T} performed in the light-cone collinear approach, to the dipole picture by expressing the hard part of the process through its Fourier transform in coordinate space. We show that in the Wandzura-Wilczek approximation the impact factor up to twist 3 factorises in the wave function of the photon combined with the distribution amplitudes of the {rho}-meson and the colour dipole scattering amplitude with the t-channel gluons. We show also that beyond the Wandzura-Wilczek approximation, the hard contribution of the amplitude still exhibits the signature of the interaction of a single colour dipole with the t-channel gluons. This result allows a phenomenological approach of the helicity amplitudes of the leptoproduction of vector meson, by combining our results to a dipole/target scattering amplitude model.

  13. The dipole representation of vector meson electroproduction beyond leading twist

    International Nuclear Information System (INIS)

    Besse, A.; Szymanowski, L.; Wallon, S.

    2013-01-01

    We link the recent computation beyond leading twist of the impact factor of the transition γ T ⁎ →ρ T performed in the light-cone collinear approach, to the dipole picture by expressing the hard part of the process through its Fourier transform in coordinate space. We show that in the Wandzura–Wilczek approximation the impact factor up to twist 3 factorises in the wave function of the photon combined with the distribution amplitudes of the ρ-meson and the colour dipole scattering amplitude with the t-channel gluons. We show also that beyond the Wandzura–Wilczek approximation, the hard contribution of the amplitude still exhibits the signature of the interaction of a single colour dipole with the t-channel gluons. This result allows a phenomenological approach of the helicity amplitudes of the leptoproduction of vector meson, by combining our results to a dipole/target scattering amplitude model.

  14. Odderon and photon exchange in electroproduction of pseudoscalar mesons

    CERN Document Server

    Berger, Edgar R.; Dosch, Hans Gunter; Kilian, W.; Nachtmann, O.; Rueter, M.

    1999-01-01

    We investigate the reaction $e p \\to e PS X$ where PS denotes a pseudoscalar meson $\\pi^0, \\eta, \\eta'$, or $\\eta_c$ and X either a proton or resonance or continuum states into which the proton can go by diffractive excitation. At high energies photon and odderon exchange contribute to the reaction. The photon exchange contribution is evaluated exactly using data for the total virtual photon-proton absorption cross section. The odderon exchange contribution is calculated in nonperturbative QCD, using functional integral techniques and the model of the stochastic vacuum. For the proton we assume a quark-diquark structure as suggested by the small odderon amplitude in $pp$ and $p \\bar{p}$ forward scattering. We show that odderon exchange leads to a much larger inelastic than elastic PS production cross section. Observation of our reaction at HERA would establish the soft odderon as an exchange object on an equal footing with the soft pomeron and would give us valuable insight into both the nucleon structure and...

  15. Separated response functions in exclusive, forward pi(+/-) electroproduction on deuterium

    NARCIS (Netherlands)

    Huber, G.M.; Blok, H.P.; Butuceanu, C.; Gaskell, D.; Horn, T.; Mack, D.J.; Abbott, D.; Aniol, K.; Anklin, H.; Armstrong, C.; Arrington, J.; Assamagan, K.; Avery, S.; Baker, O.K.; Barrett, B.; Beise, E.J.; Bochna, C.; Boeglin, W.; Brash, E.J.; Breuer, H.; Chang, C.C.; Chant, N.; Christy, M.E.; Dunne, J.; Eden, T.; Ent, R.; Fenker, H.; Gibson, E.F.; Gilman, R.; Gustafsson, K.; IIinton, W.; IIolt, R.J.; Jackson, I.I.; Jin, S.; Jones, M.K.; Keppel, C.E.; Kim, P.H.; Kim, W.; King, P.M.; Klein, A.; Koltenuk, D.; Kovaltchouk, V.; Liang, M.; Liu, J.; Lolos, G.J.; Lung, A.; Margaziotis, D.J.; Markowitz, P.; Matsumura, A.; Mckee, D.; Meekins, D.; Mitchell, J.; Miyoshi, T.; Mkrtchyan, H.; Mueller, B.; Niculescu, G.; Niculescu, I.; Okayasu, Y.; Pentchev, L.; Perdrisat, C.; Pitz, D.; Potterveld, D.; Punjabi, V.; Qin, L.M.; Reimer, P.E.; Reinhold, J.; Roche, J.; Roos, P.G.; Sarty, A.; Shin, I.K.; Smith, G.R.; Stepanyan, S.; Tang, L.G.; Tadevosyan, V.; Tvaskis, V.; Van der Meer, R.L.J.; Vansyoc, K.; Van Westrum, D.; Vidakovic, S.; Volmer, J.; Vulcan, W.; Warren, G.; Wood, S.A.; Xu, C.; Yan, C.; Zhao, W.-.; Zheng, X.; Zihlmann, B.

    2015-01-01

    Background: Measurements of forward exclusive meson production at different squared four-momenta of the exchanged virtual photon, Q2, and at different four-momentum transfer, t, can be used to probe QCD's transition from meson-nucleon degrees of freedom at long distances to quark-gluon degrees of

  16. Helicity and isospin asymmetries in the electroproduction of nucleon resonances

    International Nuclear Information System (INIS)

    Warns, M.; Pfeil, W.; Rollnik, H.

    1989-10-01

    We investigate the helicity asymmetries and isospin ratios of ratiative transition amplitudes for nucleon resonances electroproduced off proton and neutron targets at momentum transfers of Q 2 ≤3 GeV 2 . Calculations were done in the framework of a relativized constituent quark model which includes many-body effects due to the quark interaction potential and to a relativistic treatment of the center-of-mass motion of the three quark system. We find significant deviations from the predictions of the nonrelativistic quark models and the SU(6) W algebraic approach based on the single quark transition hypothesis. Our calculated relativistic corrections lead to an overall better agreement with the experimental data. The question if some of the low-lying P-wave baryons are of hermaphrodite nature is briefly discussed. Finally we analyse the electroexcitation of the missing [20,1 + ] P-wave resonances. (orig.)

  17. Kaon electroproduction at large four-momentum transfer

    International Nuclear Information System (INIS)

    Markowitz, P.

    2004-01-01

    Exclusive H(e, e'K)Y data were taken in January, March and April of 2001 at the Jefferson Lab Hall A. The electrons and kaons were detected in coincidence in the hall's two High Resolution Spectrometers (HRS). The kaon arm of the pair had been specially outfitted with two aerogel Cerenkov threshold detectors, designed to separately provide pion and proton particle identification thus allowing kaon identification. Preliminary data show the cross section's dependence on the invariant mass, W, along with results of systematic studies. Ultimately the data will be used to perform a Rosenbluth Separation as well, separating the longitudinal from the transverse response functions. (author)

  18. Weak quasielastic electroproduction of hyperons with polarization observables

    Energy Technology Data Exchange (ETDEWEB)

    Akbar, F.; Sajjad Athar, M.; Fatima, A.; Singh, S.K. [Aligarh Muslim University, Department of Physics, Aligarh (India)

    2017-07-15

    With the availability of high luminosity electron beams at the accelerators, there is now the possibility of studying weak quasielastic hyperon production off the proton, i.e. e{sup -}p → ν{sub e}Y(Y = Λ,Σ{sup 0}), which will enable the determination of the nucleon-hyperon vector and axial-vector transition form factors at high Q{sup 2} in the strangeness sector and provide test of the Cabibbo model, G-invariance, CVC, PCAC hypotheses and SU(3) symmetry. In this work, we have studied the total cross section, differential cross section as well as the longitudinal and perpendicular components of polarization of the final hyperons (Λ and Σ{sup 0} produced in these reactions) and presented numerical results for these observables and their sensitivity to the transition form factors. (orig.)

  19. Low-energy photo- and electroproduction for physical pions

    International Nuclear Information System (INIS)

    MacMullen, J.T.

    1979-02-01

    The background resonance Δ(1230), Nsup(*)(1520), Nsup(*)(1470) and Nsup(*)(1535)pion and axial-vector amplitudes are first calculated in the soft pion and on-shell configuration, respectively. Then a comparison is made with the usual soft pion theorems and on-shell low-energy expansions of current algebra as worked out in the previous paper. The agreement is good and we also deduce a nucleon dipole form factor axial-vector mass of msub(A)approximately equal to 1,23 GeV. Finally an approximate value for the non-strange current quark mass of m equal to 0,64 +- 1,11μ is extracted from the data

  20. Exclusive ρ0 electroproduction on the proton at CLAS

    International Nuclear Information System (INIS)

    Morrow, S.A.; De Masi, R.; Guidal, M.; Bouchigny, S.; Didelez, J.P.; Fradi, A.; Hadjidakis, C.; Hourany, E.; Jo, H.S.; MacCormick, M.; Moreno, B.; Niccolai, S.; Garcon, M.; Audit, G.; Marchand, C.; Morand, L.; Procureur, S.; Sabatie, F.; Laget, J.M.; Smith, E.S.; Avakian, H.; Burkert, V.D.; Carman, D.S.; Cords, D.; Degtyarenko, P.V.; Deur, A.; Elouadrhiri, L.; Guo, L.; Gyurjyan, V.; Ito, M.M.; Kubarovsky, V.; Mecking, B.A.; Mestayer, M.D.; Niczyporuk, B.B.; Nozar, M.; Sapunenko, V.; Sharabian, Y.G.; Stepanyan, S.; Weygand, D.P.; Wolin, E.; Yegneswaran, A.; Adams, G.; Cummings, J.P.; Khetarpal, P.; Li, Ji; Stoler, P.; Adhikari, K.P.; Amaryan, M.J.; Bueltmann, S.; Careccia, S.L.; Dharmawardane, K.V.; Dodge, G.E.; Guler, N.; Hyde-Wright, C.E.; Juengst, H.G.; Kalantarians, N.; Klein, A.; Klimenko, A.V.; Kuhn, S.E.; Niroula, M.R.; Qin, L.M.; Tkachenko, S.; Weinstein, L.B.; Zhang, J.; Aghasyan, M.; De Sanctis, E.; Mirazita, M.; Anefalos Pereira, S.; Polli, E.; Rossi, P.; Anghinolfi, M.; Battaglieri, M.; Corvisiero, P.; De Vita, R.; Ricco, G.; Ripani, M.; Taiuti, M.; Asryan, G.; Dashyan, N.; Egiyan, K.S.; Gevorgyan, N.; Hakobyan, H.; Bagdasaryan, H.; Baillie, N.; Butuceanu, C.; Fersch, R.; Griffioen, K.A.; Ball, J.P.; Collins, P.; Dugger, M.; Pasyuk, E.; Ritchie, B.G.; Baltzell, N.A.; Cazes, A.; Djalali, C.; Dzyubak, O.P.; Gothe, R.W.; Graham, L.; Guillo, M.; Langheinrich, J.; Lu, H.Y.; Preedom, B.M.; Tedeschi, D.J.; Tur, C.; Wood, M.H.; Zhao, Z.W.; Barrow, S.; Blaszczyk, L.; Bookwalter, C.; Chen, S.; Coltharp, P.; Crede, V.; Dennis, L.; Eugenio, P.; Hanretty, C.; McAleer, S.; Ostrovidov, A.I.; Park, S.; Riccardi, G.; Saini, M.S.; Stokes, B.E.; Bedlinskiy, I.; Kossov, M.; Mikhailov, K.; Pivnyuk, N.; Pogorelko, O.; Pozdniakov, S.; Serov, V.S.; Stavinsky, A.; Vlassov, A.V.; Bektasoglu, M.; Bellis, M.; Bradford, R.; Dickson, R.; Feuerbach, R.J.; McCracken, M.; McNabb, J.W.C.; Meyer, C.A.; Moriya, K.; Schumacher, R.A.; Williams, M.; Benmouna, N.; Berman, B.L.; Briscoe, W.J.; Dhuga, K.S.; Ilieva, Y.; Munevar, E.; Nadel-Turonski, P.; O'Rielly, G.V.; Philips, S.A.; Popa, I.; Strakovsky, I.I.; Biselli, A.S.; Bonner, B.E.; Mattione, P.; Mutchler, G.S.; Boiarinov, S.; Branford, D.; Sokhan, D.; Brooks, W.K.; Calarco, J.R.; Hersman, F.W.; Holtrop, M.; Carnahan, B.; Casey, L.; Cheng, L.; Crannell, H.; Klein, F.J.; Santoro, J.P.; Sober, D.I.; Zana, L.; Cole, P.L.; Crabb, D.; Fatemi, R.; Minehart, R.; Pierce, J.; Pocanic, D.; Smith, L.C.; Dale, D.; Forest, T.A.; Salamanca, J.; Denizli, H.; Dytman, S.; Mehrabyan, S.; Mueller, J.; Dhamija, S.; Moteabbed, M.; Schott, D.; Doughty, D.; Egiyan, H.; El Fassi, L.; Hafidi, K.; Fedotov, G.; Ishkhanov, B.S.; Isupov, E.L.; Sharov, D.; Shvedunov, N.V.; Gavalian, G.; Gilfoyle, G.P.; Rubin, P.D.; Giovanetti, K.L.; Girod, F.X.; Goetz, J.T.; Gohn, W.; Markov, N.; Zhao, B.; Gordon, C.I.O.; Hassall, N.; Ireland, D.G.; Johnstone, J.R.; Kellie, J.D.; Livingston, K.; McKinnon, B.; Melone, J.J.; Paterson, C.; Rosner, G.; Hardie, J.; Heddle, D.; Hicks, K.; Hleiqawi, I.; Keller, D.; Mibe, T.; Jenkins, D.

    2009-01-01

    The ep→e'pρ 0 reaction has been measured using the 5.754 GeV electron beam of Jefferson Lab and the CLAS detector. This represents the largest ever set of data for this reaction in the valence region. Integrated and differential cross-sections are presented. The W, Q 2 and t dependences of the cross-section are compared to theoretical calculations based on the t-channel meson-exchange Regge theory, on the one hand, and on quark handbag diagrams related to Generalized Parton Distributions (GPDs) on the other hand. The Regge approach can describe at the ∼30% level most of the features of the present data while the two GPD calculations that are presented in this article which succesfully reproduce the high-energy data strongly underestimate the present data. The question is then raised whether this discrepancy originates from an incomplete or inexact way of modelling the GPDs or the associated hard scattering amplitude or whether the GPD formalism is simply inapplicable in this region due to higher-twists contributions, incalculable at present. (orig.)

  1. Beam-spin asymmetries from semi-inclusive pion electroproduction

    Science.gov (United States)

    Gohn, W.; Avakian, H.; Joo, K.; Ungaro, M.; Adhikari, K. P.; Aghasyan, M.; Amaryan, M. J.; Anderson, M. D.; Anefalos Pereira, S.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Biselli, A. S.; Bono, J.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Djalali, C.; Doughty, D.; Dupre, R.; El Alaoui, A.; El Fassi, L.; Eugenio, P.; Fedotov, G.; Fleming, J. A.; Forest, T.; Garçon, M.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gothe, R. W.; Griffioen, K. A.; Guegan, B.; Guo, L.; Hafidi, K.; Hanretty, C.; Harrison, N.; Hattawy, Mohammad; Hicks, K.; Ho, D.; Holtrop, M.; Hyde, C.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Jo, H. S.; Keller, D.; Khandaker, M.; Khetarpal, P.; Kim, W.; Klein, F. J.; Koirala, S.; Kubarovsky, V.; Kuhn, S. E.; Kuleshov, S. V.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; Mayer, M.; McKinnon, B.; Mineeva, T.; Mirazita, M.; Mokeev, V.; Movsisyan, A.; Nadel-Turonski, P.; Niccolai, S.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Pappalardo, L. L.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Peng, P.; Phillips, J. J.; Pisano, S.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Prok, Y.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Ritchie, B. G.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Seraydaryan, H.; Sharabian, Y. G.; Simonyan, A.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Stoler, P.; Strakovsky, I. I.; Stepanyan, S.; Strauch, S.; Tang, W.; Tkachenko, S.; Vernarsky, B.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zonta, I.; CLAS Collaboration

    2014-04-01

    We have measured the moment ALUsinϕ corresponding to the polarized electron beam-spin asymmetry in semi-inclusive deep inelastic scattering. ALUsinϕ is a twist-3 quantity providing information about quark-gluon correlations. Data were taken with the CLAS Spectrometer at Jefferson Lab using a 5.498 GeV longitudinally polarized electron beam and an unpolarized liquid hydrogen target. All three pion channels (π+, π0 and π-) were measured simultaneously over a large range of kinematics within the virtuality range Q2≈ 1.0-4.5 GeV2. The observable was measured with better than 1% statistical precision over a large range of z, PT, xB, and Q2, which permits comparison with several reaction models. The discussed measurements provide an upgrade in statistics over previous measurements, and serve as the first evidence for the negative sign of the π- sinϕ moment.

  2. and electro-production of mesons with arbitrary spins

    Indian Academy of Sciences (India)

    carried out by straightforward methods'. These formulae apply directly for photo- production of other pseudoscalar mesons like η. In the case of the isovector pion, an earlier isospin analysis by Watson [13] was made use of to express each one of these amplitudes Fi(i = 1–4) in terms of three independent nucleon isospin ...

  3. Exclusive channels in semi-inclusive production of pions and kaons

    Energy Technology Data Exchange (ETDEWEB)

    Markus Diehl; Wolfgang Kugler; Andreas Schaefer; Christian Weiss

    2005-06-01

    We investigate the role of exclusive channels in semi-inclusive electroproduction of pions and kaons. Using the QCD factorization theorem for hard exclusive processes we evaluate the cross sections for exclusive pseudoscalar and vector meson production in terms of generalized parton distributions and meson distribution amplitudes. We investigate the uncertainties arising from the modeling of the nonperturbative input quantities. Combining these results with available experimental data, we compare the cross sections for exclusive channels to that obtained from quark fragmentation in semi-inclusive deep inelastic scattering. We find that rho0 production is the only exclusive channel with significant contributions to semi-inclusive pion production at large z and moderate Q2. The corresponding contribution to kaon production from the decay of exclusively produced phi and Kstar is rather small.

  4. Exclusive channels in semi-inclusive production of pions and kaons

    International Nuclear Information System (INIS)

    Markus Diehl; Wolfgang Kugler; Andreas Schaefer; Christian Weiss

    2005-01-01

    We investigate the role of exclusive channels in semi-inclusive electroproduction of pions and kaons. Using the QCD factorization theorem for hard exclusive processes we evaluate the cross sections for exclusive pseudoscalar and vector meson production in terms of generalized parton distributions and meson distribution amplitudes. We investigate the uncertainties arising from the modeling of the nonperturbative input quantities. Combining these results with available experimental data, we compare the cross sections for exclusive channels to that obtained from quark fragmentation in semi-inclusive deep inelastic scattering. We find that rho0 production is the only exclusive channel with significant contributions to semi-inclusive pion production at large z and moderate Q2. The corresponding contribution to kaon production from the decay of exclusively produced phi and Kstar is rather small

  5. Extracting integrated and differential cross sections in low energy heavy-ion reactions from backscattering measurements

    Energy Technology Data Exchange (ETDEWEB)

    Sargsyan, V. V. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Yerevan State University, 0025 Yerevan (Armenia); Adamian, G. G., E-mail: adamian@theor.jinr.ru [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Antonenko, N. V. [Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Mathematical Physics Department, Tomsk Polytechnic University, 634050 Tomsk (Russian Federation); Diaz-Torres, A. [European Centre for Theoretical Studies in Nuclear Physics and Related Areas, I-38123 Villazzano, Trento (Italy); Gomes, P. R. S. [de Fisica, Universidade Federal Fluminense, Av. Litorânea, s/n, Niterói, R.J. 24210-340 (Brazil); Lenske, H. [Institut für Theoretische Physik der Justus–Liebig–Universität, D–35392 Giessen (Germany)

    2016-07-07

    We suggest new methods to extract elastic (quasi-elastic) scattering angular distribution and reaction (capture) cross sections from the experimental elastic (quasi-elastic) backscattering excitation function taken at a single angle.

  6. The Physics of Ultraperipheral Collisions at the LHC

    CERN Document Server

    Baltz, A J; D'Enterria, D G; Frankfurt, L; Gelis, François; Guzey, V; Hencken, K; Kharlov, Yu; Klasen, M; Klein, S R; Nikulin, V; Nystrand, J; Pshenichnov, I A; Sadovsky, S; Scapparone, E; Seger, J; Strikman, M I; Tverskoy, M; Vogt, R; White, S N; Wiedemann, Urs Achim; Yepes, P; Zhalov, M

    2008-01-01

    We discuss the physics of large impact parameter interactions at the LHC: ultraperipheral collisions (UPCs). The dominant processes in UPCs are photon-nucleon (nucleus) interactions. The current LHC detector configurations can explore small $x$ hard phenomena with nuclei and nucleons at photon-nucleon center-of-mass energies above 1 TeV, extending the $x$ range of HERA by a factor of ten. In particular, it will be possible to probe diffractive and inclusive parton densities in nuclei using several processes. The interaction of small dipoles with protons and nuclei can be investigated in elastic and quasi-elastic $J/\\psi$ and $\\Upsilon$ production as well as in high $t$ $\\rho^0$ production accompanied by a rapidity gap. Several of these phenomena provide clean signatures of the onset of the new high gluon density QCD regime. The LHC is in the kinematic range where nonlinear effects are several times larger than at HERA. Two-photon processes in UPCs are also studied. In addition, while UPCs play a role in limit...

  7. Electroproduction of neutral pions in the Hall A at the Jefferson Laboratory; Electroproduction de pions neutres dans le Hall A au Jefferson Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Fuchey, Eric [Blaise Pascal Univ., Aubiere (France)

    2010-06-01

    The past decade has seen a strong evolution of the study of the hadron structure through exclusive processes, allowing to access to a more complete description of this structure. Exclusive processes include DVCS (Deeply Virtual Compton Scattering) as well as hard exclusive meson production. This document is particularly focussed on the latter, and more particularly on exclusive neutral pion production. In this thesis is described the analysis of triple coincidence events H(e, e'γγ)X, which were a consequent by-product of the DVCS experiment which occured during Fall 2004 at Jefferson Lab Hall A, to extract the ep → epπ0 cross section. This cross section has been measured at two values of four-momentum transfer Q2 = 1.9 GeV2 and Q2 = 2.3 GeV2. The statistical precision for these measurements is achieved at better than 5 %. The kinematic range allows to study the evolution of the extracted cross section as a function of Q2 and W. Results are be confronted with Regge inspired calculations and Generalized (GPD) predictions. An intepretation of our

  8. A gauge-invariant chiral unitary framework for kaon photo- and electroproduction on the proton

    International Nuclear Information System (INIS)

    Borasoy, B.; Bruns, P.C.; Nissler, R.; Meissner, U.G.

    2007-01-01

    We present a gauge-invariant approach to photoproduction of mesons on nucleons within a chiral unitary framework. The interaction kernel for meson-baryon scattering is derived from the chiral effective Lagrangian and iterated in a Bethe-Salpeter equation. Within the leading-order approximation to the interaction kernel, data on kaon photoproduction from SAPHIR, CLAS and CBELSA/TAPS are analyzed in the threshold region. The importance of gauge invariance and the precision of various approximations in the interaction kernel utilized in earlier works are discussed. (orig.)

  9. Photo- and electroproduction of K+ Lambda with a unitarity-restored isobar model

    Czech Academy of Sciences Publication Activity Database

    Skoupil, Dalibor; Bydžovský, Petr

    2018-01-01

    Roč. 97, č. 2 (2018), č. článku 025202. ISSN 2469-9985 R&D Projects: GA ČR(CZ) GA15-04301S Institutional support: RVO:61389005 Keywords : kaon photoproduction * electromagnetic produciton * K+ Lambda Subject RIV: BE - Theoretical Physics OBOR OECD: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect) Impact factor: 3.820, year: 2016

  10. An NLO calculation of the electroproduction of large-E bot hadrons

    International Nuclear Information System (INIS)

    Aurenche, P.; Basu, Rahul; Fontannaz, M.; Godbole, R.M.

    2004-01-01

    We present a next-to-leading order calculation of the cross section for the leptoproduction of large-E bot hadrons and we compare our predictions with H1 data on the forward production of π 0 . We find large higher order corrections and an important sensitivity to the renormalization and factorization scales. These large corrections are shown to arise in part from BFKL-like diagrams at the lowest order. (orig.)

  11. Recoil polarization measurements in $\\pi^{0}$ electroproduction at the peak of the Delta (1232)

    CERN Document Server

    Sarty, A J

    2001-01-01

    This talk presents a status report, along with some preliminary/on line results, from the Thomas Jefferson National Accelerator Facility (JLab) experiment E91011 which was performed in Hall A at JLab during the summer of 2000. The experiment measured angular distributions for the differential cross section and recoil proton polarizations in the reaction p(e, e'p) pi /sup 0/. Kinematics were chosen to be centered at a CMS energy of W=1232 MeV, and a squared four momentum transfer of Q/sup 2/=1.0 (GeV/c)/sup 2/. The primary objectives of the experiment are to isolate contributions from the resonant quadrupole N to Delta , multipole S/sub 1+/, and to clarify the role of other, small nonresonant multipole contributions to the reaction. Details of the experiment itself will be given, along with sample spectra illustrating the quality and coverage of the data obtained. (10 refs) .

  12. Sin$\\phi$ azimuthal asymmetry in semi-inclusive electroproduction on longitudinally polarized nucleon

    CERN Document Server

    Oganessian, K.A.; Bianchi, N.; Kotzinian, A.M.

    1998-01-01

    We investigate the $sin \\phi$ azimuthal asymmetry in the semi-inclusive deep-inelastic lepton scattering off longitudinally polarized nucleon target arising from the time reversal odd structures. The order 1/Q contributions of the leading twist and twist-three distribution and fragmentation functions to that asymmetry for the certain kinematical conditions are numerically estimated.

  13. Electroproduction of Φ(1020) Mesons at High Q2 with CLAS

    Energy Technology Data Exchange (ETDEWEB)

    Santoro, Joseph P. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)

    2007-10-11

    This analysis studies the reaction ep → e'p'φ in the kinematical range 1.6 ≤ Q2 ≤ 3.8 GeV2 and 2.0 ≤ W ≤ 3.0 GeV at CLAS. After successful signal identification, total and differential cross sections are measured and compared to the world data set. Comparisons are made to the predictions of the Jean-Mart Laget (JML) model based on Pomeron plus 2-gluon exchange. The overall scaling of the total cross section was determined to be 1/Q4.6+/-1.7 which is compatible within errors to the Vector Meson Dominance prediction of 1/ Q4 as well as to the expected behavior of a quark and gluon exchange-dominated model described by Generalized Parton Distributions of 1/Q6. The differential cross section dσ/dΦ was used to determine that the s-channel helicity conservation (SCHC) assumption is valid within the precision of the current data. SCHC leads to a simple expression for the decay angular distribution from which R, the ratio of the longitudinal to the transverse cross section, can be extracted. Under the assumption of SCHC, we determine R = 1.33 ± 0.18 at an average Q2 of 2.21 GeV2 which leads to a determination of the longitudinal cross section sL = 5.3 ± 1.3 nb for exclusive φ production.

  14. Measurement of New Observables from the pi+pi- Electroproduction off the Proton

    Energy Technology Data Exchange (ETDEWEB)

    Trivedi, Arjun [Univ. of South Carolina, Columbia, SC (United States)

    2016-12-01

    Knowledge of the Universe as constructed by human beings, in order to tackle its complexity, can be thought to be organized at varying scales at which it is observed. Implicit in such an approach is the idea of a smooth evolution of knowledge between scales and, therefore, access to how Nature constructs the visible Universe beginning from its most fundamental constituents. New and, in a sense, fundamental phenomena may typically be emergent as the scale of observation changes. The study of the Strong Interaction, which is responsible for the construction of the bulk of the visible matter in the Universe (98% by mass), in this sense, is a labor of exploring evolutions and unifying aspects of its knowledge found at varying scales ranging from interaction of quarks and gluons as represented by the theory of Quantum Chromodynamics (QCD) at small space-time scale to emerging dressed quark and even meson-baryon degrees of freedom mostly described by effective models as the space-time scale increases. A direct effort to study the Strong Interaction over this scale forms the basis of an international collaborative effort often referred to as the N* program. The core work of this thesis is an experimental analysis prompted by the need to measure experimental observables that are of particular interest to the theory-experiment epistemological framework of this collaboration. While the core of this thesis, therefore, discusses the nature of the experimental analysis and presents its results which will serve as input to the N* program's epistemological framework, the particular nature of this framework in the context of not only the Strong Interaction, but also that of the physical science and human knowledge in general will be used to motivate and introduce the experimental analysis and its related observables.

  15. The HKS experiment on {lambda}-hypernuclear spectroscopy via electroproduction at JLab

    Energy Technology Data Exchange (ETDEWEB)

    Tang, L. [Department of Physics, Hampton University, Hampton, VA 23668, U.S.A. (United States); Physics Division, Thomas Jefferson National Accelerator Facility, Newport News, VA 23606, U.S.A. (United States); Yuan, L. [Department of Physics, Hampton University, Hampton, VA 23668 (United States); Acha, A.; Ahmidouch, A.; Androic, D.; Asaturyan, A.; Asaturyan, R.; Baker, O.K.; Baturin, P.; Benmokhtar, F.; Bosted, P.; Carlini, R.; Chen, X.; Christy, M.; Cole, L.; Danagoulian, S.; Daniel, A.; Dharmawardane, V.; Egiyan, K.; Elaasar, M.; Ent, R.; Fenker, H.; Fujii, Y.; Furic, M.; Gan, L.; Gaskell, D.; Gasparian, A.; Gibson, Ed.F.; Gueye, P.; Halkyard, R.; Hashimoto, O.; Honda, D.; Horn, T.; Hu, B.; Hu, S.; Hungerford, Ed.V.; Ispiryan, M.; Johnston, K.; Jones, M.; Kalantarians, N.; Kaneta, M.; Kato, F.; Kato, S.; Kawama, D.; Kepple, C.; Li, Y.; Luo, W.; Mack, D.; Margaryan, A.; Marikyan, G.; Maruyama, N.; Matsumura, A.; Miyoshi, T.; Mkrtchyan, A.; Mkrtchyan, H.; Nakamura, S.N.; Navasardyan, T.; Niculescu, G.; Niculescu, M.-I.; Nomura, H.; Nonaka, K.; Ohtani, A.; Okayasu, Y.; Pamela, P.; Perez, N.; Petkovic, T.; Randeniya, S.; Reinhold, J.; Rivera, R.; Roche, J.; Rodriguez, V.M.; Sato, Y.; Seva, T.; Simicevic, N.; Smith, G.; Sumihama, M.; Song, Y.; Tadevosyan, V.; Takahashi, T.; Tamura, H.; Tvaskis, V.; Vulcan, W.; Wang, B.; Wells, S.; Wood, S.; Yan, C.; Zamkochian, S

    2007-06-15

    The HKS (Jlab E01-011) experiment on spectroscopy of {lambda}-hypernuclei using (e,e'K{sup +}) reaction was successfully carried out in 2005. This paper gives a brief description of the experiment and its technique and shows some of the preliminary spectra that are still under analysis.

  16. Electron beam asymmetry measurements from exclusive pi0 electroproduction in the Delta(1232) resonance region

    Energy Technology Data Exchange (ETDEWEB)

    K. Joo

    2003-05-01

    The polarized longitudinal-transverse structure function sigma_LT'in the p(e,e'p)pi^0 reaction has been measured for the first time in the Delta(1232) resonance region for invariant mass W = 1.1 - 1.3 GeV and at four-momentum transfer Q^2 = 0.40 and 0.65 GeV^2. Data were taken at the Thomas Jefferson National Accelerator Facility with the CEBAF Large Acceptance Spectrometer (CLAS) using longitudinally polarized electrons at an energy of 1.515 GeV. This newly measured sigma_LT' provides new and unique information on the interference between resonant and non-resonant amplitudes in the Delta(1232) resonance region. The comparison to recent phenomenological calculations shows sensitivity to the description of non-resonant amplitudes and higher resonances.

  17. Electroproduction of π0 mesons on nuclei in deep inelastic region

    International Nuclear Information System (INIS)

    Badalyan, R.G.; Gasparyan, A.O.; Gevorkyan, S.R.; Gulkanyan, H.R.; Mkrtchyan, H.G.; Vartapetyan, H.H.

    1990-01-01

    The proposed project is a part of experimental program of Yerevan Physics Institute for the investigation of mechanisms of virtual photon absorption and hadronization of quarks in nuclear media in the processes of deep inelastic scattering of electrons with energies up to 4.5 GeV. In this project the possibility for the study of reaction (e, e'π 0 ) with a view of obtaining the information about space-time structure of quark hadronization process as well as the dependence of characteristics of hadron formation process on kinematical variables of the virtual photon (ν, Q 2 ) and of the detected hadron (Z=E h /ν) are discussed. The characteristics of experimental set-up and also the results of computer simulation of the experiment are given. 27 refs.; 12 figs

  18. Measurement of the Double Spin Asymmetry in π+ electroproduction with CLAS

    International Nuclear Information System (INIS)

    Raffaella De Vita

    2000-01-01

    The present thesis describes the measurement of the double spin asymmetry in the ep → eπ + n reaction. This represents the only existing measurement for this observable. The reaction is identified detecting the scattered electron and the emitted pion and using the missing mass technique to identify the neutron. The asymmetry is evaluated as a function of the four-momentum transfer Q 2 , the invariant mass W and the pion center of mass angle θ*. These are in fact the variables that determine the transition amplitudes for the process. The W range of this measurement varies from the pion threshold to a maximum value of 1.8 GeV, exploring the full resonance region. The results obtained with this analysis in the evaluation of the spin asymmetry are presented. The outline of the thesis can be summarized as follows. The first chapter describes the physics motivation that are at the basis of this experiment. The second and third chapters illustrate the design of the CLAS detector and the polarized target. The fourth chapter gives a description of the event reconstruction and to the event selection while the analysis procedure is described in chapter five. Chapter six discusses the results of this measurement, including the evaluation of the systematic uncertainty and the comparison with a physics model

  19. Exchange mechanisms for single photo- and electroproduction using the dual fermion model

    International Nuclear Information System (INIS)

    Becker, L.; Weigt, G.

    1976-01-01

    Single pion real and virtual photoproduction data are compared with phenomenological dual fermion amplitudes, which were previously applied to quasi-two body vector and tensor meson production. The similar structures of the photon and the corresponding vector meson data (in the s-channel helicity system) such as spikes and dips, usually described by Regge pole/Regge cut interferences, are reproduced by the dual Born amplitudes. Predictions of the model for the differential cross sections, in particular their parts for natural and unnatural spin-parity t-channel exchanges as well as their mass dependence, and photon and target asymmetries are in reasonable agreement with the experimental data. (author)

  20. Electroproduction and photoproduction of vector mesons and generalized vector meson dominance

    International Nuclear Information System (INIS)

    Fraas, H.; Kuroda, M.

    1977-05-01

    Using generalized vector meson dominance, electro- and photoproduction of vector mesons is studied. The unnatural parity exchange part of ω(1.2) production is estimated to be about one fourth of that of ω-production. The off diagonal transition model suggests the suppression of diffractive rho(1.2) and ω(1.2) production. (orig.) [de

  1. The HKS experiment on Lambda--hypernuclear spectroscopy via electroproduction at JLab

    International Nuclear Information System (INIS)

    Tang, Liguang; Yuan, Lulin; Acha Quimper, Armando; Ahmidouch, Abdellah; Androic, Darko; Asaturyan, Arshak; Asaturyan, Razmik; Baker, O.; Baturin, Pavlo; Benmokhtar, Fatiha; Bosted, Peter; Carlini, Roger; Chen, X.; Christy, Michael; Cole, Leon; Danagoulian, Samuel; Daniel, Aji; Dharmawardane, Kahanawita; Egiyan, Kim; Elaasar, Mostafa; Ent, Rolf; Fenker, Howard; Fujii, Yu; Furic, Miroslav; Gan, Liping; Gaskell, David; Gasparian, Ashot; Gibson, Edward; Gueye, Paul; Halkyard, Rebekah; Hashimoto, Osamu; Honda, D.; Horn, Tanja; Hu, Bitao; Hu, S.; Hungerford, Ed; Ispiryan, Mikayel; Johnston, Kathleen; Jones, Mark; Kalantarians, Narbe; Kaneta, M.; Kato, F.; Kato, Seigo; Kawama, Daisuke; Keppel, Cynthia; Li, Y.; Luo, Wei; Mack, David; Margaryan, Amur; Marikyan, Gagik; Maruyama, Nayuta; Matsumura, Akihiko; Miyoshi, Toshinobu; Mkrtchyan, Arthur; Mkrtchyan, Hamlet; Nakamura, Satoshi; Navasardyan, Tigran; Niculescu, Gabriel; Niculescu, Maria-Ioana; Nomura, Hiroshi; Nonaka, Kenichi; Ohtani, Atsushi; Okayasu, Yuichi; Pamela, Priscilla; Perez, Naipy; Petkovic, Tomislav; Randeniya, Kapugodage; Reinhold, Joerg; Rivera Castillo, Roberto; Roche, Julie; Rodriguez, Victor; Sato, Yoshinori; Seva, Tomislav; Simicevic, Neven; Smith, Gregory; Sumihama, Mizuki; Song, Yujun; Tadevosyan, Vardan; Takahashi, Toshiyuki; Tamura, Hirokazu; Tvaskis, Vladas; Vulcan, William; Wang, B.; Wells, Stephen; Wood, Stephen; Yan, Chen; Zamkochian, S.

    2008-01-01

    The HKS (Jlab E01-011) experiment on spectroscopy of Lambda-hypernuclei using (e,e'K+) reaction was successfully carried out in 2005. This paper gives a brief description of the experiment and its technique and shows some of the preliminary spectra that are still under analysis.

  2. Factorization properties and their probabilistic interpretation in polarized electroproduction and annihilation processes

    International Nuclear Information System (INIS)

    Antoniadis, I.; Kounnas, C.

    1981-01-01

    We describe the factorization properties of polarized deep-inelastic and semi-inclusive annihilation structure functions in the Bjorken limit. We present a simple physical interpretation of the factorization results that relates the factorized quantities to the terms appearing in a decomposition of an effective spin-density matrix of a virtual quark. We give, through one-loop level, all the calculable quantities needed to parametrize the scaling violation of the structure functions in both spacelike and timelike processes

  3. Inclusive electroproduction of hadrons in the fragmentation region of a virtual photon

    International Nuclear Information System (INIS)

    Kiselev, A.V.; Petrov, V.A.; Taranov, A.Yu.

    1978-01-01

    The purpose of the article is to use Jost-Leh'ann-Dyson representation for asymptotic behaviour studying of adron deep-non-elastic electrobirth inclusive process in a current fragmentation field. It is shown that inclusive electrobirth process in the field of vertual photon fragmentation posesses automodel hehaviour with logarithm presision in case when spectral functions have polynominal asympthotics at lambdasub(1,2)sup(2)→infinity

  4. On the theory of electroproduction of small relative momentum nucleon pairs on atomic nuclei

    International Nuclear Information System (INIS)

    Nagornyj, S.I.; Inopin, E.V.

    1979-01-01

    Problems concerning knocking-out of nucleon pairs from atomic nuclei by high-energy electrons are studied. Dependences of cross sections of different processes of the knocking-out on the nucleon relative momentum in a pair are considered. Probabilities of different processes of the knocking-out are compared. A comparison of probabilities of total and three-particle splittings of a 4 He nucleus is performed. On total splitting in the formation of the cross section energy dependence the levels of observable and non-observable subsystems shown to take place. It has been stated that the cross section cannot be increased at the expense of levels of both subsystems simultaneously

  5. Hadronization Studies via π0 Electroproduction off D, C, Fe, and Pb

    Energy Technology Data Exchange (ETDEWEB)

    Mineeva, Taisiya [Univ. of Connecticut, Storrs, CT (United States)

    2013-12-01

    Propagation of partons and formation of hadrons is a topic of interest to multiple communities. New data available from Drell-Yan measurements at FermiLab, heavy ion collisions in RHIC and LHC, SIDIS measurements from HERMES at DESY and Jefferson Lab, all bring different types of information on short distance processes. DIS data obtained in the well understood nuclear medium provide direct information on hadron formation, essential to lay the groundwork for testing theoretical tools. A series of semi-inclusive DIS measurements were performed on D, C, Fe, Pb nuclei. The data were collected during the EG2 run period using the CLAS at Jefferson Lab. A double-target system consisting of liquid deuterium and one of the solid targets was exposed to a 5.014 GeV electron beam. The goal of the experiment is to extract hadronic multiplicity ratios (R$h\\atop{A}$) off nuclei of varying size. These are believed to have sensitivity to the parton fragmentation as well as in-medium hadronization.

  6. Evidence for the onset of color transparency in ρ0 electroproduction off nuclei

    Science.gov (United States)

    CLAS Collaboration; El Fassi, L.; Zana, L.; Hafidi, K.; Holtrop, M.; Mustapha, B.; Brooks, W. K.; Hakobyan, H.; Zheng, X.; Adhikari, K. P.; Adikaram, D.; Aghasyan, M.; Amaryan, M. J.; Anghinolfi, M.; Arrington, J.; Avakian, H.; Baghdasaryan, H.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Bookwalter, C.; Branford, D.; Briscoe, W. J.; Bültmann, S.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Cole, P. L.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Daniel, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Dey, B.; Dickson, R.; Djalali, C.; Dodge, G. E.; Doughty, D.; Dupre, R.; Egiyan, H.; El Alaoui, A.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Gabrielyan, M. Y.; Garçon, M.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guo, L.; Hanretty, C.; Heddle, D.; Hicks, K.; Holt, R. J.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jawalkar, S. S.; Keller, D.; Khandaker, M.; Khetarpal, P.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuhn, S. E.; Kuleshov, S. V.; Kuznetsov, V.; Laget, J. M.; Lu, H. Y.; MacGregor, I. J. D.; Mao, Y.; Markov, N.; Mayer, M.; McAndrew, J.; McKinnon, B.; Meyer, C. A.; Mineeva, T.; Mirazita, M.; Mokeev, V.; Moreno, B.; Moutarde, H.; Munevar, E.; Nadel-Turonski, P.; Ni, A.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Pappalardo, L. L.; Paremuzyan, R.; Park, K.; Park, S.; Pasyuk, E.; Anefalos Pereira, S.; Phelps, E.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Protopopescu, D.; Raue, B. A.; Reimer, P. E.; Ricco, G.; Rimal, D.; Ripani, M.; Ritchie, B. G.; Rosner, G.; Rossi, P.; Sabatié, F.; Saini, M. S.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seraydaryan, H.; Sharabian, Y. G.; Smith, E. S.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Stepanyan, S. S.; Stepanyan, S.; Stoler, P.; Strauch, S.; Taiuti, M.; Tang, W.; Taylor, C. E.; Tedeschi, D. J.; Tkachenko, S.; Ungaro, M.; Vernarsky, B.; Vineyard, M. F.; Voskanyan, H.; Voutier, E.; Watts, D.; Weinstein, L. B.; Weygand, D. P.; Wood, M. H.; Zachariou, N.; Zhao, B.; Zhao, Z. W.

    2012-06-01

    We have measured the nuclear transparency of the incoherent diffractive A(e,e‧ρ0) process in 12C and 56Fe targets relative to 2H using a 5 GeV electron beam. The nuclear transparency, the ratio of the produced ρ0's on a nucleus relative to deuterium, which is sensitive to ρA interaction, was studied as function of the coherence length (lc), a lifetime of the hadronic fluctuation of the virtual photon, and the four-momentum transfer squared (Q2). While the transparency for both 12C and 56Fe showed no lc dependence, a significant Q2 dependence was measured, which is consistent with calculations that included the color transparency effects.

  7. Cross Sections for the Exclusive Photon Electroproduction on the Proton and Generalized Parton Distributions

    Science.gov (United States)

    Jo, H. S.; Girod, F. X.; Avakian, H.; Burkert, V. D.; Garçon, M.; Guidal, M.; Kubarovsky, V.; Niccolai, S.; Stoler, P.; Adhikari, K. P.; Adikaram, D.; Amaryan, M. J.; Anderson, M. D.; Anefalos Pereira, S.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Compton, N.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dupre, R.; Alaoui, A. El; Fassi, L. El; Elouadrhiri, L.; Fedotov, G.; Fegan, S.; Filippi, A.; Fleming, J. A.; Garillon, B.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Goetz, J. T.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guegan, B.; Guler, N.; Guo, L.; Hafidi, K.; Hakobyan, H.; Harrison, N.; Hattawy, M.; Hicks, K.; Hirlinger Saylor, N.; Ho, D.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Jenkins, D.; Joo, K.; Joosten, S.; Keller, D.; Khachatryan, G.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Kuhn, S. E.; Kuleshov, S. V.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; McKinnon, B.; Meziani, Z. E.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Moutarde, H.; Movsisyan, A.; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Net, L. A.; Niculescu, G.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Park, K.; Pasyuk, E.; Phillips, J. J.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Prok, Y.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Simonyan, A.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Tian, Ye; Tkachenko, S.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

    2015-11-01

    Unpolarized and beam-polarized fourfold cross sections (d4σ /d Q2d xBd t d ϕ ) for the e p →e'p'γ reaction were measured using the CLAS detector and the 5.75-GeV polarized electron beam of the Jefferson Lab accelerator, for 110 (Q2,xB,t ) bins over the widest phase space ever explored in the valence-quark region. Several models of generalized parton distributions (GPDs) describe the data well at most of our kinematics. This increases our confidence that we understand the GPD H , expected to be the dominant contributor to these observables. Through a leading-twist extraction of Compton form factors, these results support the model predictions of a larger nucleon size at lower quark-momentum fraction xB.

  8. Plane-wave impulse approximation extraction of the neutron magnetic form factor from Quasi-Elastic 3(rvec H)e((rvec e),e(prime)) at Q2 = 0.3 to 0.6 (GeV/c)2

    International Nuclear Information System (INIS)

    Xu, W.; Anderson, B.; Auberbach, L.; Averett, T.; Bertozzi, W.; Black, T.; Calarco, J.; Cardman, L.; Cates, G.D.; Chai, Z.W.; Chen, J.P.; Choi, S.; Chudakov, E.; Churchwell, S.; Corrado, G.S.; Crawford, C.; Dale, D.; Deur, A.; Djawotho, P.; Donnelly, T.W.; Dutta, D.; Finn, J.M.; Gao, H.; Gilman, R.; Glamazdin, A.V.; Glashausser, C.; Gloeckle, Walter; Golak, J.; Gomez, J.; Gorbenko, V.G.; Hansen, J.O.; Hersman, F.W.; Higinbotham, D.W.; Holmes, R.; Howell, C.R.; Hughes, E.; Humensky, B.; Incerti, S.; Jager, C.W. de; Jensen, J.S.; Jiang, X.; Jones, C.E.; Jones, M.; Kahl, R.; Kamada, H.; Kievsky, A.; Kominis, I.; Korsch, W.; Kramer, K.; Kumbartzki, G.; Kuss, M.; Lakuriqi, E.; Liang, M.; Liyanage, N.; LeRose, J.; Malov, S.; Margaziotis, D.J.; Martin, J.W.; McCormick, K.; McKeown, R. D.; McIlhany, K.; Meziani, Z.E.; Michaels, R.; Miller, G.W.; Mitchell, J.; Nanda, S.; Pace, E.; Pavlin, T.; Petratos, G.G.; Pomatsalyuk, R.I.; Pripstein, D.; Prout, D.; Ransome, R.D.; Roblin, Y.; Rvachev, M.; Saha, A.; Salme, G.; Schnee, M.; Shin, T.; Slifer, K.; Souder, P.A.; Strauch, S.; Suleiman, R.; Sutter, M.; Tipton, B.; Todor, L.; Viviani, M.; Vlahovic, B.; Watson, J.; Williamson, C.F.; Witala, H.; Wojtsekhowski, B.; Xiong, F.; Yeh, J.; Zolnierczuk, P.

    2003-01-01

    A high precision measurement of the transverse spin-dependent asymmetry A T in 3 (rvec H)e((rvec e),e(prime)) quasielastic scattering was performed in Hall A at Jefferson Lab at values of the squared four-momentum transfer, Q 2 , between 0.1 and 0.6 (GeV/c) 2 . A T is sensitive to the neutron magnetic form factor, G M n . Values of G M n at Q 2 = 0.1 and 0.2 (GeV/c) 2 , extracted using Faddeev calculations, were reported previously. Here, we report the extraction of G M n for the remaining Q 2 -values in the range from 0.3 to 0.6 (GeV/c) 2 using a Plane-Wave Impulse Approximation calculation. The results are in good agreement with recent precision data from experiments using a deuterium target

  9. Development of a focal-plane drift chamber for low-energetic pions and experimental determination of an inverse transfer matrix for the short-orbit spectrometer

    International Nuclear Information System (INIS)

    Ding, M.

    2004-10-01

    The three-spectrometer facility at the Mainz microtron MAMI was supplemented by an additional spectrometer, which is characterized by its short path-length and therefore is called Short Orbit Spectrometer (SOS). At nominal distance from target to SOS (66 cm) the particles to be detected cover a mean path-length between reaction point and detector of 165 cm. Thus for pion electroproduction close to threshold in comparison to the big spectrometers the surviving probability of charged pions with momentum 100 MeV/c raises from 15% to 73%. Consequently the systematic error (''myon contamination''), as for the proposed measurement of the weak form-factors G A (Q 2 ) and G P (Q 2 ), reduces significantly. The main subject of this thesis is the drift chamber for the SOS. Its small relative thickness (0.03% X 0 ), reducing multiple scattering, is optimized with regard to detecting low-energy pions. Due to the innovative character of the driftchamber geometry a dedicated software for track-reconstruction, efficiency-determination etc. had to be developed. A comfortable feature for calibrating the drift path-drift time-relation, represented by cubic splines, was implemented. The resolution of the track detector in the dispersive plane is 76 μaem for the spatial and 0.23 for the angular coordinate (most probable error) and, correspondingly, 110 μm and 0.29 in the non-dispersive plane. For backtracing the reaction quantities from the detector coordinates the inverse transfer-matrix of the spectrometer was determined. For this purpose electrons were scattered quasi-elastically from protons inside the 12 C-nucleus, thus defining the starting angles of the electrons by holes of a sieve collimator. The resulting experimental values for the angular resolution at the target amount to σ φ =1.3 mrad and σ θ =10.6 mrad resp. The momentum calibration of the SOS only can be achieved by quasi-elastic scattering (two-arm experiment). For this reason the contribution of the proton

  10. Experimental review of exclusive processes in two photon reactions

    International Nuclear Information System (INIS)

    Ronan, M.T.

    1986-07-01

    Recent experimental results on exclusive final stated produced in photon-photon interactions are reviewed. Comparisons between experiments and with perturbative QCD calculations are made for meson and baryon pair production. New results on vector meson pair (rho 0 rho 0 ,rho 0 omega,rho 0 phi,...) production and production of multiparticle (KKππ,K*Kπ,...) final states are summarized. 34 refs

  11. Angular correlations in γγ → p0p0 near threshold

    International Nuclear Information System (INIS)

    Althoff, M.; Braunschweig, W.; Gather, K.; Kirschfink, F.J.; Luebelsmeyer, K.; Martyn, H.U.; Peise, G.; Rimkus, J.; Sander, H.G.; Schmitz, D.

    1982-09-01

    We present an analysis of rho 0 rho 0 production by two photons in the rho 0 rho 0 invariant mass range from 1.2 to 2.0 GeV. From a study of the angular correlations in the process γγ → rho 0 rho 0 → π + π - π + π - we exclude a dominant contribution from Jsup(P) = 0 - or 2 - states. The data indicate sizeable contributions from Jsup(P) = 0 + for four pion masses Msub(4π) + for Msub(4π) > 1.7 GeV. The data are also well described by a model with isotropic production and uncorrelated isotropic decay of the rho 0 's. The cross section stays high below the nominal rho 0 rho 0 threshold, i.e. Msub(4π) 0 rho 0 production is found to decrease steeply with increasing Msub(4π). Upper limits for the couplings of the iota(1440) and the THETA(1640) to γγ and rho 0 rho 0 are given: GAMMA(iota → γγ) x B(iota → rho 0 rho 0 ) 0 rho 0 ) < 1.2 keV (95% C.L.). (orig.)

  12. Beam-helicity azimuthal asymmetry measured with the recoil detector in exclusive electroproduction of real photons at HERMES

    Energy Technology Data Exchange (ETDEWEB)

    Yu Weilin

    2009-11-15

    The experiments at the HERA storage ring at DESY yielded a large contribution to the understanding of the nucleon structure. They used for this the deep inelastic scattering (DIS) in the collision of electrons/positrons and protons. The HERMES experiment at DESY applied the longitudinally polarized electron or positron beam with an energy of 27.6 GeV together with a polarized or unpolarized gas target in order to study the spin structure of the nucleon. By the measurement of deeply virtual Compton scattering (DVCS) the generalized parton distributions (GPDs) can be determined. These allow a unified description of the nucleon structure. Furthermore they give an experimental approach to the orbital angular momenta of the quarks. However the DVCS process is not discriminable from the Bethe-Heitler (BH) process, in which the scattered electron produces by bremsstrahlung processes a real photon. But it was proved that the interference caused by this indiscriminability of BH and DVCS presents the approach to the DVCS amplitude. This pursues by the measurement of asymmetries of the BH-DVCS cross section in relation to the beam charge, the beam polarization, or the target polarization. The HERMES spectrometer was constructed in order to measure semi-inclusive and inclusive DIS processes. The extraction of the azimutal asymmetries in relation to the beam helicity from the data of 2007 at the hydrogen target were performed in this thesis. The extracted asymmetry amplitudes from the elastic BH/DVCS process agree well with the earlier measurements of HERMES. Furthermore for the first time the asymmetry of {delta}{sup +} resonances was extracted, however the events are because of the low statistics affect with large uncertainties.

  13. Separated kaon electroproduction cross section and the kaon form factor from 6 GeV JLab data

    NARCIS (Netherlands)

    Carmignotto, M.; Ali, S.; Aniol, K.; Arrington, J.; Barrett, B.; Beise, E. J.; Blok, H. P.; Boeglin, W.; Brash, E. J.; Breuer, H.; Chang, C. C.; Christy, M. E.; Dittmann, A.; Ent, R.; Fenker, H.; Gaskell, D.; Gibson, E.; Holt, R. J.; Horn, T.; Huber, G. M.; Jin, S.; Jones, M. K.; Keppel, C. E.; Kim, W.; King, P. M.; Kovaltchouk, V.; Liu, J.; Lolos, G. J.; MacK, D. J.; Margaziotis, D. J.; Markowitz, P.; Matsumura, A.; Meekins, D.; Miyoshi, T.; Mkrtchyan, H.; Niculescu, G.; Niculescu, I.; Okayasu, Y.; Pegg, I. L.; Pentchev, L.; Perdrisat, C.; Potterveld, D.; Punjabi, V.; Reimer, P. E.; Reinhold, J.; Roche, J.; Sarty, A.; Smith, G. R.; Tadevosyan, V.; Volmer, J.

    2018-01-01

    The H1(e,e′K+)Λ reaction was studied as a function of the Mandelstam variable -t using data from the E01-004 (FPI-2) and E93-018 experiments that were carried out in Hall C at the 6 GeV Jefferson Laboratory. The cross section was fully separated into longitudinal and transverse components, and two

  14. Beam-helicity azimuthal asymmetry measured with the recoil detector in exclusive electroproduction of real photons at HERMES

    International Nuclear Information System (INIS)

    Yu Weilin

    2009-11-01

    The experiments at the HERA storage ring at DESY yielded a large contribution to the understanding of the nucleon structure. They used for this the deep inelastic scattering (DIS) in the collision of electrons/positrons and protons. The HERMES experiment at DESY applied the longitudinally polarized electron or positron beam with an energy of 27.6 GeV together with a polarized or unpolarized gas target in order to study the spin structure of the nucleon. By the measurement of deeply virtual Compton scattering (DVCS) the generalized parton distributions (GPDs) can be determined. These allow a unified description of the nucleon structure. Furthermore they give an experimental approach to the orbital angular momenta of the quarks. However the DVCS process is not discriminable from the Bethe-Heitler (BH) process, in which the scattered electron produces by bremsstrahlung processes a real photon. But it was proved that the interference caused by this indiscriminability of BH and DVCS presents the approach to the DVCS amplitude. This pursues by the measurement of asymmetries of the BH-DVCS cross section in relation to the beam charge, the beam polarization, or the target polarization. The HERMES spectrometer was constructed in order to measure semi-inclusive and inclusive DIS processes. The extraction of the azimutal asymmetries in relation to the beam helicity from the data of 2007 at the hydrogen target were performed in this thesis. The extracted asymmetry amplitudes from the elastic BH/DVCS process agree well with the earlier measurements of HERMES. Furthermore for the first time the asymmetry of Δ + resonances was extracted, however the events are because of the low statistics affect with large uncertainties

  15. Experiment E89-044 of quasi-elastic diffusion 3He(e,e'p) at Jefferson Laboratory: Analyze cross sections of the two body breakup in parallel kinematics; Experience E89-044 de diffusion quasi-elastique 3he(e,e'p) au Jefferson Laboratory : analyse des sections efficaces de desintegration a deux corps en cinematique parallele

    Energy Technology Data Exchange (ETDEWEB)

    Penel-Nottaris, Emilie [Univ. Joseph Fourier Grenoble (France)

    2004-07-01

    The Jefferson Lab Hall A experiment has measured the 3He(e,e'p) reaction cross sections. The separation of the longitudinal and transverse response functions for the two-body breakup reaction in parallel kinematics allows to study the bound proton electromagnetic properties in the 3He nucleus and the involved nuclear mechanisms beyond impulse approximation. Preliminary cross sections show some disagreement with theoretical predictions for the forward angles kinematics around 0 MeV/c missing momenta, and sensitivity to final state interactions and 3He wave functions for missing momenta of 300 MeV/c.

  16. Magnetic dynamics of small alpha-Fe2O3 and NiO particles

    DEFF Research Database (Denmark)

    Lefmann, K.; Bødker, Franz; Hansen, Mikkel Fougt

    1999-01-01

    particles, we observed a clear double peak in the energy distribution of the antiferromagnetic signal, in addition to a quasi-elastic peak. We interpret the double peak to respresent collective magnetic excitations. Broadening of the central quasi-elastic peak with increasing temprature is interpreted...

  17. Magnetic dynamics of small α-Fe2O3 and NiO particles studied by neutron scattering

    DEFF Research Database (Denmark)

    Lefmann, Kim; Bødker, Franz; Hansen, Mikkel Fougt

    1999-01-01

    particles, we observed a clear double peak in the energy distribution of the antiferromagnetic signal, in addition to a quasi-elastic peak. We interpret the double peak to represent collective magnetic excitations. Broadening of the central quasi-elastic peak with increasing temperature is interpreted...

  18. Vector-vector production in photon-photon interactions

    International Nuclear Information System (INIS)

    Ronan, M.T.

    1988-01-01

    Measurements of exclusive untagged /rho/ 0 /rho/ 0 , /rho//phi/, K/sup *//bar K//sup */, and /rho/ω production and tagged /rho/ 0 /rho/ 0 production in photon-photon interactions by the TPC/Two-Gamma experiment are reviewed. Comparisons to the results of other experiments and to models of vector-vector production are made. Fits to the data following a four quark model prescription for vector meson pair production are also presented. 10 refs., 9 figs

  19. Concluding remarks presented at the Symposium on heavy ion reaction dynamics on the tandem energy region

    International Nuclear Information System (INIS)

    Betts, R.R.

    1988-01-01

    This paper discusses the divisions between different heavy ion reaction processes. Fusion, deep inelastic, quasi-elastic and elastic interactions are discussed in terms of coupled channel calculations. 20 refs., 8 figs

  20. Measurement of the photon electroproduction cross section at JLab with the goal of performing a Rosenbluth separation of the DVCS contribution

    OpenAIRE

    Martí Jiménez-Argüello, Alejandro Miguel

    2014-01-01

    An elementary particle is a particle whose substructure is unknown, thus it is unknown whether it is composed of other particles. Historically, the atom constituent particles (electrons, protons and neutrons) were all regarded as elementary particles. However, with the discovery of the magnetic moment of the proton, it became clear that the proton did not belong to this category. With further experimentation, more evidence was found that protons and neutrons, as well as all hadrons, were comp...

  1. Single-spin asymmetry in electro-production of {pi}{sup +} {pi}{sup -} pairs from a transversely polarized proton target at the HERMES experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Xiao-Rui

    2008-10-15

    In this thesis, the measurement of an azimuthal amplitude of the asymmetry in the lepto-production of {pi}{sup +}{pi}{sup -} pairs at the HERMES experiment is reported. The experiment was carried out at DESY in Germany, utilizing the longitudinally polarized 27.6 GeV electron/positron beam of the HERA storage ring in combination with a longitudinally or transversely polarized gaseous target internal to the beam pipe. For the present measurement, the transversely polarized proton target was used and the beam polarization was averaged out in order to measure the asymmetry A{sub UT}. A Ring Imaging Cerenkov (RICH) detector allows the precise identification of pions, kaons and protons over essentially the entire momentum range of the experiment. The asymmetry A{sub UT} for {pi}{sup +}{pi}{sup -} pair production was measured for the first time in the world by HERMES. The amplitudes are extracted as functions of different kinematic variables, which can facilitate the comparison with the theoretical models and the extraction of transversity with combination of the measurement of the dihadron fragmentation function. (orig.)

  2. Single-spin asymmetry in electro-production of π+ π- pairs from a transversely polarized proton target at the HERMES experiment

    International Nuclear Information System (INIS)

    Lu, Xiao-Rui

    2008-09-01

    In this thesis, the measurement of an azimuthal amplitude of the asymmetry in the lepto-production of π + π - pairs at the HERMES experiment is reported. The experiment was carried out at DESY in Germany, utilizing the longitudinally polarized 27.6 GeV electron/positron beam of the HERA storage ring in combination with a longitudinally or transversely polarized gaseous target internal to the beam pipe. For the present measurement, the transversely polarized proton target was used and the beam polarization was averaged out in order to measure the asymmetry A UT . A Ring Imaging Cerenkov (RICH) detector allows the precise identification of pions, kaons and protons over essentially the entire momentum range of the experiment. The asymmetry A UT for π + π - pair production was measured for the first time in the world by HERMES. The amplitudes are extracted as functions of different kinematic variables, which can facilitate the comparison with the theoretical models and the extraction of transversity with combination of the measurement of the dihadron fragmentation function. (orig.)

  3. Q^2 Dependence of the S_{11}(1535) Photocoupling and Evidence for a P-wave resonance in eta electroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Haluk Denizli; James Mueller; Steven Dytman; M.L. Leber; R.D. Levine; J. Miles; Kui Kim; Gary Adams; Moscov Amaryan; Pawel Ambrozewicz; Marco Anghinolfi; Burin Asavapibhop; G. Asryan; Harutyun Avakian; Hovhannes Baghdasaryan; Nathan Baillie; Jacques Ball; Nathan Baltzell; Steve Barrow; V. Batourine; Marco Battaglieri; Kevin Beard; Ivan Bedlinski; Ivan Bedlinskiy; Mehmet Bektasoglu; Matthew Bellis; Nawal Benmouna; Nicola Bianchi; Angela Biselli; Billy Bonner; Sylvain Bouchigny; Sergey Boyarinov; Robert Bradford; Derek Branford; William Briscoe; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; Sharon Careccia; Daniel Carman; Catalina Cetina; Shifeng Chen; Philip Cole; Alan Coleman; Patrick Collins; Philip Coltharp; Dieter Cords; Pietro Corvisiero; Donald Crabb; Volker Crede; John Cummings; Natalya Dashyan; Raffaella De Vita; Enzo De Sanctis; Pavel Degtiarenko; Lawrence Dennis; Alexandre Deur; Kalvir Dhuga; Richard Dickson; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; P. Dragovitsch; Michael Dugger; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; Lamiaa Elfassi; Latifa Elouadrhiri; A. Empl; Paul Eugenio; Laurent Farhi; Renee Fatemi; Gleb Fedotov; Gerald Feldman; Robert Feuerbach; Tony Forest; Valera Frolov; Herbert Funsten; Sally Gaff; Michel Garcon; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Pascal Girard; Francois-Xavier Girod; John Goetz; Atilla Gonenc; Ralf Gothe; Keith Griffioen; Michel Guidal; Matthieu Guillo; Nevzat Guler; Lei Guo; Vardan Gyurjyan; Kawtar Hafidi; Hayk Hakobyan; Rafael Hakobyan; John Hardie; David Heddle; F. Hersman; Kenneth Hicks; Ishaq Hleiqawi; Maurik Holtrop; Jingliang Hu; Charles Hyde; Charles Hyde-Wright; Yordanka Ilieva; David Ireland; Boris Ishkhanov; Eugeny Isupov; Mark Ito; David Jenkins; Hyon-Suk Jo; Kyungseon Joo; Henry Juengst; Narbe Kalantarians; J.H. Kelley; James Kellie; Mahbubul Khandaker; K. Kim; Wooyoung Kim; Andreas Klein; Franz Klein; Mike Klusman; Mikhail Kossov; Laird Kramer; V. Kubarovsky; Joachim Kuhn; Sebastian Kuhn; Sergey Kuleshov; Jeff Lachniet; Jean Laget; Jorn Langheinrich; David Lawrence; Kenneth Livingston; Haiyun Lu; K. Lukashin; Marion MacCormick; Joseph Manak; Nikolai Markov; Simeon McAleer; Bryan McKinnon; John McNabb; Bernhard Mecking; Mac Mestayer; Curtis Meyer; Tsutomu Mibe; Konstantin Mikhaylov; Ralph Minehart; Marco Mirazita; Rory Miskimen; Viktor Mokeev; Kei Moriya; Steven Morrow; M. Moteabbed; Valeria Muccifora; Gordon Mutchler; Pawel Nadel-Turonski; James Napolitano; Rakhsha Nasseripour; Steve Nelson; Silvia Niccolai; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Grant O' Rielly; Mikhail Osipenko; Alexander Ostrovidov; Kijun Park; Evgueni Pasyuk; Craig Paterson; Gerald Peterson; Sasha Philips; Joshua Pierce; Nikolay Pivnyuk; Dinko Pocanic; Oleg Pogorelko; Ermanno Polli; S. Pozdniakov; Barry Preedom; John Price; Yelena Prok; Dan Protopopescu; Liming Qin; Brian Raue; Gregory Riccardi; Giovanni Ricco; Marco Ripani; Barry Ritchie; Federico Ronchetti; Guenther Rosner; Patrizia Rossi; David Rowntree; Philip Rubin; Franck Sabatie; Konstantin Sabourov; Julian Salamanca; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Aziz Shafi; Youri Sharabian; Jeremiah Shaw; Nikolay Shvedunov; Sebastio Simionatto; Alexander Skabelin; Elton Smith; Lee Smith; Daniel Sober; Daria Sokhan; M. Spraker; Aleksey Stavinskiy; Samuel Stepanyan; Stepan Stepanyan; Burnham Stokes; Paul Stoler; I.I. Strakovsky; Steffen Strauch; Mauro Taiuti; Simon Taylor; David Tedeschi; Ulrike Thoma; R. Thompson; Avtandil Tkabladze; Svyatoslav Tkachenko; Clarisse Tur; Maurizio Ungaro; Michael Vineyard; Alexander Vlassov; Kebin Wang; Daniel Watts; Lawrence Weinstein; Henry Weller; Dennis Weygand; M. Williams; Elliott Wolin; Michael Wood; Amrit Yegneswaran; Junho Yun; Lorenzo Zana; Jixie Zhang; Bo Zhao; Zhiwen Zhao

    2007-07-01

    New cross sections for the reaction $ep \\to e'\\eta p$ are reported for total center of mass energy $W$=1.5--2.3 GeV and invariant squared momentum transfer $Q^2$=0.13--3.3 GeV$^2$. This large kinematic range allows extraction of new information about response functions, photocouplings, and $\\eta N$ coupling strengths of baryon resonances. A sharp structure is seen at $W\\sim$ 1.7 GeV. The shape of the differential cross section is indicative of the presence of a $P$-wave resonance that persists to high $Q^2$. Improved values are derived for the photon coupling amplitude for the $S_{11}$(1535) resonance. The new data greatly expands the $Q^2$ range covered and an interpretation of all data with a consistent parameterization is provided.

  4. Determination of the strange quarks's contribution to the proton spin in semi-inclusive deep inelastic electroproduction of K and π mesons

    International Nuclear Information System (INIS)

    Alizade, V.N.; Efremov, A.V.

    1991-01-01

    A possibility of extracting pure contribution of s-quarks to the proton spin in the processes 1+A->1+h+X(A=p,nN; h=K + ,K 0 ,K 0 ,π + show that measurements of the quantities δσ K and δυ π . 10 refs.; 1 fig

  5. The α3S corrections to the Bjorken sum rule for polarized electro-production and to the Gross-Llewellyn Smith sum rule

    International Nuclear Information System (INIS)

    Larin, S.A.; Nationaal Inst. voor Kernfysica en Hoge-Energiefysica; Vermaseren, J.A.M.

    1990-01-01

    The next-next-to-leading order QCD corrections to the Gross-Llewellyn Smith sum rule for deep inelastic neutrino-nucleon scattering and to the Bjorken sum rule for polarized electron-nucleon scattering have been computed. This involved the proper treatment of γ 5 inside the loop integrals with dimensional regularization. It is found that the difference between the two sum rules are entirely due to a class of 6 three loop graphs and is of the order of 1% of the leading QCD term. Hence the Q 2 behavior of both sum rules should be the same if the physics is described adequately by the lower order terms of perturbative QCD. (author). 12 refs.; 2 figs.; 4 tabs

  6. Off-shell effects in the model of spectator electroproduction of cumulative nucleons; Ehffekty skhoda s massovoj poverkhnosti v modeli spektatornogo obrazovaniya kumulyativnykh nuklonov

    Energy Technology Data Exchange (ETDEWEB)

    Sargsyan, M M

    1992-12-31

    The effects of deeply bound nucleons are considered in the reaction of deuteron quasielastic electro disintegration, where the spectator nucleon and scattered electrons are registered in coincidence. Both, the off-shell influence on the description of nucleon motion in nuclear surrounding and the modification of deeply bound nucleon form - factors are investigated as two aspects of the off-shell effect manifestation. The possibility to control the extent of interacting nucleon binding energy by varying the spectator nucleon kinematic parameters (p{sub s},{theta}{sub s},{phi}{sub s}) is an advantage of the reactions considered. The cross section ratios of these processes are considered under specific kinematical conditions, which allow to investigate unambiguously the manifestations of deeply bound effects. To estimate the extent of the phenomena expected, we present the results of calculation of R ratios in the framework of models that take the off-shell effects into account differently. The effects of bound nucleon form - factor modification are estimated according to the model of mini delocalization, which predicts the bound nucleon swelling in nuclear environment. 28 refs.

  7. Modelling the active site of NiFe hydrogenases: new catalysts for the electro-production of H2 and mechanistic studies

    International Nuclear Information System (INIS)

    Canaguier, S.

    2009-01-01

    NiFe hydrogenases are unique metalloenzymes that catalyze H + /H 2 interconversion with remarkable efficiency close to the thermodynamic potential. Their active site consists of a hetero-bimetallic complex containing a nickel ion in a sulphur-rich environment connected by two thiolate bridges to an organometallic cyano-carbonyl iron moiety. In order to improve the understanding of the enzymatic mechanism and to obtain new base-metal electrocatalysts for H 2 production, we synthesized a series of bio-inspired low molecular weight model complexes with the butterfly structure Ni(μ-S 2 )M (M= Ru, Mn and Fe). All these compounds displayed a catalytic activity of hydrogen production. Modulating the electronic and steric properties of the ruthenium center allowed optimizing the catalytic performances of these compounds in terms of stability, catalytic rate and overpotential. Mechanistic studies of the catalytic cycle of the Ni-Ru complexes have also been carried out. They allowed us to suggest a bio-relevant bridging hydride as the catalytic intermediate. Finally, we synthesized one of the first Ni-Fe complexes that is both a structural and a functional model of NiFe hydrogenase. (author) [fr

  8. Correlation between the availability of dopamine transporter and olfactory function in healthy subjects

    International Nuclear Information System (INIS)

    Pak, Kyoungjune; Kim, Keunyoung; Kim, In Joo; Lee, Myung Jun; Lee, Jae Meen; Kim, Bum Soo; Kim, Seong-Jang

    2018-01-01

    Olfactory dysfunction in Parkinson's disease is usually prodromal to other symptoms. In this study, we aimed to explore the association of olfactory function with the availabilities of striatal dopamine transporter (DAT) in healthy subjects. Data used in the preparation of this article were obtained from Parkinson's Progression Markers Initiative database (www.ppmi-info.org/data). The study population consisted of healthy controls with screening 123 I-FP-CIT single photon emission tomography (SPECT). University of Pennsylvania Smell Identification Test (UPSIT) was assessed to evaluate the olfactory function. Totally, 181 healthy subjects (117 male, 64 female) with 123 I-FP-CIT SPECT data were included in this study. Specific binding ratios (SBRs) of the caudate nucleus (rho = -0.4217, p < 0.0001), putamen (rho = -0.2292, p = 0.0019), and striatum (rho=-0.3425, p < 0.0001) showed a reduction with ageing. SBRs of the caudate nucleus, putamen, and striatum were positively correlated with UPSIT (rho = 0.3716, p < 0.0001; rho = 0.3655, p < 0.0001; rho = 0.3880, p < 0.0001). After controlling for age by partial correlation, SBRs of the caudate nucleus, putamen, and striatum showed an influence on UPSIT (rho = 0.3288, p < 0.0001; rho = 0.3374, p < 0.0001; rho = 0.3511, p < 0.0001). Olfactory function is associated with the availability of striatal DAT independent of age in healthy subjects. (orig.)

  9. Binary projectile fragmentation of 12C at an incident energy of 33.3 MeV/nucleon

    CERN Document Server

    Förtsch, S V; Gadioli, E; Bassini, R; Buthelezi, E Z; Cerutti, F; Connell, S H; Cowley, A A; Fujita, H; Mabiala, J; Mairani, A; Mira, J; Papka, P; Neveling, R; Smit, F D

    2010-01-01

    Direct binary projectile fragmentation is being investigated for the case where a 400 MeV 12C projectile breaks up into an particle and a 8Be fragment in the interaction with a thin 93Nb and 197Au target. While the 8Be fragments were measured at 9 , the correlated particles were detected in an angular range between 16 and 30 on the opposite side of the beam. From the preliminary results presented here one may obtain information on the amount of quasi-elastic fragmentation (both fragments do not suffer any further interactions after they are produced). These experimental results indicate that the quasi-elastic break-up process is the dominant contribution to the measured correlation spectra. As was also observed in earlier work, the most forward quasi-elastically emitted particles have energies exceeding the beam velocity.

  10. EPJ Web of Conferences, Proceedings of the joint meeting QENS/WINS 2014

    International Nuclear Information System (INIS)

    Frick, B.; Koza, M.M.; Boehm, M.; Mutka, H.

    2015-01-01

    The 11. QENS (Quasi-Elastic Neutron Scattering) conference and the 6. WINS (Workshop on Inelastic Neutron Spectrometers) were held for the second time together as the joint meeting QENS/WINS 2014. QENS 2014 aims to highlight topical scientific activities in the investigation of the dynamics of matter using quasi-elastic neutron scattering and to envision new applications. In dynamics of matter, matter must be considered in a very broad sense since issues like dynamics of confined matter in nano-porous materials, dynamics of biological systems in relation to function, dynamics of ionic and electrolytes, dynamics of soft matter, liquids, and liquid crystals, are of concern. The aim of the WINS 2014 workshop is to overview recent developments, forthcoming projects and practice of inelastic and quasi-elastic neutron spectrometers. Related issues such as the development of data analysis software, auxiliary devices and outlook for future scientific efforts are also dealt with

  11. Search for eta '(c) decays into vector meson pairs

    NARCIS (Netherlands)

    Ablikim, M.; Achasov, M. N.; Alberto, D.; An, F. F.; An, Q.; An, Z. H.; Bai, J. Z.; Baldini, R.; Ban, Y.; Becker, J.; Berger, N.; Bertani, M.; Bian, J. M.; Boger, E.; Bondarenko, O.; Boyko, I.; Briere, R. A.; Bytev, V.; Cai, X.; Calcaterra, A. C.; Cao, G. F.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, Y.; Chen, Y. B.; Cheng, H. P.; Chu, Y. P.; Cronin-Hennessy, D.; Dai, H. L.; Dai, J. P.; Dedovich, D.; Deng, Z. Y.; Denysenko, I.; Destefanis, M.; Ding, Y.; Dong, L. Y.; Dong, M. Y.; Du, S. X.; Fang, J.; Fang, S. S.; Feng, C. Q.; Fu, C. D.; Fu, J. L.; Gao, Y.; Geng, C.; Goetzen, K.; Gong, W. X.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, Y. P.; Han, Y. L.; Hao, X. Q.; Harris, F. A.; He, K. L.; He, M.; He, Z. Y.; Heng, Y. K.; Hou, Z. L.; Hu, H. M.; Hu, J. F.; Hu, T.; Huang, B.; Huang, G. M.; Huang, J. S.; Huang, X. T.; Huang, Y. P.; Hussain, T.; Ji, C. S.; Ji, Q.; Ji, X. B.; Ji, X. L.; Jia, L. K.; Jiang, L. L.; Jiang, X. S.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Jing, F. F.; Kalantar-Nayestanaki, N.; Kavatsyuk, M.; Kuehn, W.; Lai, W.; Lange, J. S.; Leung, J. K. C.; Li, C. H.; Li, Cheng; Li, Cui; Li, D. M.; Li, F.; Li, G.; Li, H. B.; Li, J. C.; Li, K.; Li, Lei; Li, N. B.; Li, Q. J.; Li, S. L.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, X. R.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, X. T.; Liu, B. J.; Liu, C. L.; Liu, C. X.; Liu, C. Y.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H.; Liu, H. B.; Liu, H. H.; Liu, H. M.; Liu, H. W.; Liu, J. P.; Liu, K.; Liu, K.; Liu, K. Y.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, X. H.; Liu, Y. B.; Liu, Y. W.; Liu, Yong; Liu, Z. A.; Liu, Zhiqiang; Liu, Zhiqing; Loehner, H.; Lu, G. R.; Lu, H. J.; Lu, J. G.; Lu, Q. W.; Lu, X. R.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lv, M.; Ma, C. L.; Ma, F. C.; Ma, H. L.; Ma, Q. M.; Ma, S.; Ma, T.; Ma, X.; Ma, X. Y.; Maggiora, M.; Malik, Q. A.; Mao, H.; Mao, Y. J.; Mao, Z. P.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Muchnoi, N. Yu.; Nefedov, Y.; Nikolaev, I. B.; Ning, Z.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Park, J. W.; Pelizaeus, M.; Peters, K.; Ping, J. L.; Ping, R. G.; Poling, R.; Pun, C. S. J.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, X. S.; Qiu, J. F.; Rashid, K. H.; Rong, G.; Ruan, X. D.; Sarantsev, A.; Schulze, J.; Shao, M.; Shen, C. P.; Shen, X. Y.; Sheng, H. Y.; Shepherd, M. R.; Song, X. Y.; Spataro, S.; Spruck, B.; Sun, D. H.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. D.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tian, H. L.; Toth, D.; Varner, G. S.; Wang, B.; Wang, B. Q.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, Q.; Wang, Q. J.; Wang, S. G.; Wang, X. L.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. Y.; Wei, D. H.; Wen, Q. G.; Wen, S. P.; Wiedner, U.; Wu, L. H.; Wu, N.; Wu, W.; Wu, Z.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, G. M.; Xu, H.; Xu, Q. J.; Xu, X. P.; Xu, Y.; Xu, Z. R.; Xu, Z. Z.; Xue, Z.; Yan, L.; Yan, W. B.; Yan, Y. H.; Yang, H. X.; Yang, T.; Yang, Y.; Yang, Y. X.; Ye, H.; Ye, M.; Ye, M. H.; Yu, B. X.; Yu, C. X.; Yu, S. P.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, L.; Zhang, S. H.; Zhang, T. R.; Zhang, X. J.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. S.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, H. S.; Zhao, Jiawei; Zhao, Jingwei; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, S. J.; Zhao, T. C.; Zhao, X. H.; Zhao, Y. B.; Zhao, Z. G.; Zhao, Z. L.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, Y. H.; Zheng, Z. P.; Zhong, B.; Zhong, J.; Zhong, L.; Zhou, L.; Zhou, X. K.; Zhou, X. R.; Zhu, C.; Zhu, K.; Zhu, K. J.; Zhu, S. H.; Zhu, X. L.; Zhu, X. W.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zou, B. S.; Zou, J. H.; Zuo, J. X.

    2011-01-01

    The processes eta'(c) -> rho(0)rho(0), K*0K*0, and phi phi are searched for using a sample of 1.06 x 10(8) psi' events collected with the BESIII detector at the BEPCII collider. No signals are observed in any of the three final states. The upper limits on the decay branching fractions are determined

  12. The gamma N ---> Delta transition in chiral effective-field theory.

    Energy Technology Data Exchange (ETDEWEB)

    Vladimir Pascalutsa; Marc Vanderhaeghen

    2006-04-27

    We describe the pion electroproduction processes in the {Delta}(1232)-resonance region within the framework of chiral effective-field theory. By studying the observables of pion electroproduction in a next-to-leading order calculation we are able to make predictions and draw conclusions on the properties of the N {yields} {Delta} electromagnetic form factors.

  13. The $\\gamma N\\to \\De$ transition in chiral effective-field theory

    Energy Technology Data Exchange (ETDEWEB)

    Vladimir Pascalutsa; Marc Vanderhaeghen

    2006-04-27

    We describe the pion electroproduction processes in the {Delta}(1232)-resonance region within the framework of chiral effective-field theory. By studying the observables of pion electroproduction in a next-to-leading order calculation we are able to make predictions and draw conclusions on the properties of the N {yields} {Delta} electromagnetic form factors.

  14. Low-energy angular distributions for the 12C(e,π+)e' reaction

    International Nuclear Information System (INIS)

    Sealock, R.M.; Caplan, H.S.; Lolos, G.J.; Haxton, W.C.

    1981-01-01

    Angular distributions for near threshold electroproduction of positive pions from 12 C are reported and compared to theory. These data provide tests of recently developed second-order optical potentials and of the nuclear response to electroproduction in the giant resonance region

  15. Incoherent neutron scattering functions for random jump diffusion in bounded and infinite media

    International Nuclear Information System (INIS)

    Hall, P.L.; Ross, D.K.

    1981-01-01

    The incoherent neutron scattering function for unbounded jump diffusion is calculated from random walk theory assuming a gaussian distribution of jump lengths. The method is then applied to calculate the scattering function for spatially bounded random jumps in one dimension. The dependence on momentum transfer of the quasi-elastic energy broadenings predicted by this model and a previous model for bounded one-dimensional continuous diffusion are calculated and compared with the predictions of models for diffusion in unbounded media. The one-dimensional solutions can readily be generalized to three dimensions to provide a description of quasi-elastic scattering of neutrons by molecules undergoing localized random motions. (author)

  16. Collisions between heavy nuclei near the barrier

    International Nuclear Information System (INIS)

    Henning, W.

    1988-05-01

    Detailed information has recently become available on the reaction behavior in very heavy nuclear systems close to the Coulomb barrier. Starting from an experimental study of the distribution of the reaction strength above and below the barrier, the dominant reaction channels of quasi-elastic and strongly-damped processes are examined. With decreasing incident energy, the sub-barrier collisions are increasingly dominated by quasi-elastic processes. From the division of internal excitation energy, new information is obtained on the nature of the dissipative processes. (orig.)

  17. Investigation of /sup 16/O+/sup 27/Al reaction at bombarding energies below 5. 3 MeV/A

    Energy Technology Data Exchange (ETDEWEB)

    Wen-Qing, Shen; Yong-Tai, Zhu; Wen-Long, Zhan; Zhong-Yan, Guo; Shu-Zhi, Yin; Wei-Min, Qiao; En-Chiu, Wu

    1987-03-01

    Quasi elastic and deep inelastic collision induced by /sup 16/O+/sup 27/Al at the bombarding energies below 5.3 MeV/A have been studied in detail. Experimental angular energy atomic charge distribution and contour plots of the differential cross sections d/sup 3/sigma/dEd..cap omega..dZ on E-theta plan are presented, their evolution with the bombarding energies are analysed. The competion between quasi elastic and deep inelastic collision as a functon of the bombarding energies has been discussed.

  18. Pseudoscalar form factors in tau-neutrino nucleon scattering

    International Nuclear Information System (INIS)

    Hagiwara, K.; Mawatari, K.; Yokoya, H.

    2004-01-01

    We investigate the pseudoscalar transition form factors of nucleon for quasi-elastic scattering and Δ resonance production in tau-neutrino nucleon scattering via the charged current interactions. Although the pseudoscalar form factors play an important role for the τ production in neutrino-nucleon scattering, these are not known well. In this Letter, we examine their effects in quasi-elastic scattering and Δ resonance production and find that the cross section, Q 2 distribution, and spin polarization of the produced τ ± leptons are quite sensitive to the pseudoscalar form factors

  19. Dynamics in γ-Fe2O3 nanoparticles studied by time-of-flight polarized neutron scattering

    DEFF Research Database (Denmark)

    Kuhn, L.T.; Lefmann, K.; Klausen, S.N.

    2004-01-01

    The inelastic neutron-scattering signal from magnetic nanoparticles contains information on magnetic dynamics like superparamagnetic relaxation and collective magnetic excitations. Often another, very broad quasi-elastic component is observed in addition. We have studied this quasi-elastic neutron...... signal from 4 nm ferrimagnetic maghemite (gamma-Fe(2)O(3)) particles, and by means of time-of-flight polarised neutron scattering we have identified the source of (most of) this signal to be water adsorbed at the surface of the nanoparticles. A minor part of the signal has its origin in dynamics...

  20. Deuterium electrodisintegration at high recoil momentum

    International Nuclear Information System (INIS)

    Steenholen, G.

    1996-01-01

    The availability of continuous electron beams made it possible to carry out various deuterium electro-disintegration experiments in kinematical domains corresponding to a high recoil momentum. Three such experiments are discussed: 1) the left-right asymmetry with respect to the direction of the momentum transfer has been measured with good precision; 2) cross sections have been obtained in a kinematical region well above the quasi-elastic peak; 3) data have been taken in quasi-elastic kinematics that can be used to study high-momentum components in the deuterium wave function [ru

  1. Quasielastic neutron scattering facility at Dhruva reactor

    International Nuclear Information System (INIS)

    Mukhopadhyay, R.; Mitra, S.; Paranjpe, S.K.; Dasannacharya, B.A.

    2001-01-01

    Quasi-elastic neutron scattering is a powerful experimental tool for studying the various dynamical motions in solids and liquids. In this paper, we have described the salient features of the quasi-elastic neutron spectrometer in operation at Dhruva reactor at Trombay, India. The design criteria have been such as to maximise the throughput by various means like closer approach to the source, focusing a larger beam on to a sample, and Multi-Angle Reflecting X-tal mode of energy analysis. Some results of molecular motions from recently studied systems using this spectrometer are also reported

  2. Neutrino interactions with nuclei

    CERN Document Server

    Martini, M; Ericson, M; Marteau, J

    2009-01-01

    We present a model for neutrino-nucleus scattering in the energy region relevant for present and forthcoming neutrino-oscillation experiments. The model is based on the RPA treatment of the nuclear responses in the quasi-elastic and Delta-resonance region. It includes also in a phenomenological way nucleon knock-out. It aims at the description, within a single framework, of several final state channels i.e. quasi-elastic, incoherent and coherent one-pion production and two- or several-nucleon knock-out.

  3. The G0 Experiment

    International Nuclear Information System (INIS)

    Nakahara, Kazutaka

    2007-01-01

    The G0 experiment measures the parity-violating asymmetries in elastic electron-proton and quasi-elastic electron-deuteron scattering over the momentum transfers 0.12 ≤ Q2 ≤ 1.0 GeV2. These asymmetries are sensitive to the strange-quark contribution to the charge and magnetization distributions of the proton. The experiment is conducted at Jefferson Laboratory using a toroidal spectrometer designed to detect forward scattered recoil protons and backward scattered elastic and quasi-elastic electrons. The forward angle experiment was completed in 2004, and the backward angle phase of the experiment is currently taking place

  4. Pion electroproduction at threshold in the inverse channel: π-p → ne+e-. Determination method of the longitudinal multipole Lsub(0+)sup(π-) at small transfer. Preparation of the experiment

    International Nuclear Information System (INIS)

    Fonvieille, H.

    1984-01-01

    Our main is to give for the first time an experimental value of the longitudinal multipole Lsub(0+)sup(π - ) (k 2 ) for small transfers in the time-like region (/k 2 / -2 ) by studying the process: π - p → ne + e - at threshold. The pion beam is stopped in a liquid hydrogen target, and the lepton pair is detected in a double arm high-resolution, large-acceptance spectrometer (magnet + drift chambers). We describe here the preparating phases of the experiment. After a brief review of the theoretical approaches, we discuss the method for selecting the events from the background (due to: π - p → nγ, γ → e + e - , and π - p → π 0 n, π 0 → γe + e - ) and present a method for analyzing our data, from which the multiple Lsub(0+)sup(π - ) (k 2 ) is to be determined with an average 10% precision. For that purpose, we give an approximate calculation of the experimental resolution. The choice of the experimental set-up and its realization are then described. The experiment (a Clermont-LPC, Saclay-DPhN/HE, Lyon-IPN Collaboration) takes place on the ALS-pion Beam (Saclay). The whole experimental set-up has been recently checked satisfactorily [fr

  5. Wroclaw neutrino event generator

    International Nuclear Information System (INIS)

    Nowak, J A

    2006-01-01

    A neutrino event generator developed by the Wroclaw Neutrino Group is described. The physical models included in the generator are discussed and illustrated with the results of simulations. The considered processes are quasi-elastic scattering and pion production modelled by combining the Δ resonance excitation and deep inelastic scattering

  6. Radiochemistry division. Chapter 2

    International Nuclear Information System (INIS)

    Anon.

    In radiochemistry, the experiments made in 1976 were in the following fields: in nuclear chemistry, the study of heavy-ion reaction mechanisms of fusion and fission, quasi-elastic transfer reactions; in radiochemistry the study of the physico-chemical properties of the actinides and transuranium elements and the search for natural superheavy elements [fr

  7. Central Peaks and Soft Modes in Praseodymium

    DEFF Research Database (Denmark)

    Houmann, Jens Christian Gylden; Lebech, Bente; Mackintosh, A. R.

    1977-01-01

    The dhcp allotrope of Pr is a singlet ground-state system which is very close to magnetic ordering at low temperatures. We have observed quasi-elastic magnetic scattering around the q-value in the directions at which the disperion relations for the magnetic excitations have a minimum energy...

  8. Interaction of a neutral composite particle with a strong Coulomb field

    International Nuclear Information System (INIS)

    Wong, Cheuk-Yin.

    1988-01-01

    The author discusses the interaction of the quasi-composite (e/sup /plus//e/sup /minus//) system with an external electromagnetic field. This problem addresses the question of the origin of strong positron lines in quasi-elastic heavy-ion reactions. 3 refs

  9. Solution structure of a short dna fragment studied by neutron scattering

    DEFF Research Database (Denmark)

    Lederer, H.; May, R. P.; Kjems, Jørgen

    1986-01-01

    -DNA. The neutron scattering curve is well fitted by that of a rigid rod with a length of 44 nm and a diameter of 2 nm. The result were confirmed by quasi-elastic light scattering and analytical centrifugation. The neutron measurements in H2O and D2O buffer reveal a cross-sectional in homogeneity not detected by X...

  10. Real and imaginary parts of hadronic amplitudes, diffractive contributions and the Chew-Rosenzweig pomeron

    International Nuclear Information System (INIS)

    Chiu, C.B.; Tow, D.M.

    1978-01-01

    It is shown that when the f' and the diffractive elastic (and quasi-elastic) contributions are included within the Chew-Rosenzweig type solution for the pomeron, one can explain reasonably well the π and 2K - π total cross sections as well as the ratios of the real over imaginary parts of the forward π and K amplitudes. (Auth.)

  11. Neutron scattering studies of the dynamics of biological systems as a function of hydration, temperature and pressure

    International Nuclear Information System (INIS)

    Trapp, Marcus

    2010-01-01

    Incoherent elastic and quasi-elastic neutron scattering were used to measure membrane and protein dynamics in the nano- to picosecond time and Angstrom length scale. The hydration dependent dynamics of DMPC model membranes was studied using elastic and quasi-elastic neutron scattering. The elastic experiments showed a clear shift of the temperature of the main phase transition to higher temperatures with decreasing hydration level. The performed quasi-elastic measurements demonstrated nicely the influence, hydration has on the diffusive motions of the head lipid groups. Different models are necessary to fit the Q-dependence of the elastic incoherent structure factor and show therefore the reduced mobility as a result of reduced water content. In addition to temperature, pressure as a second thermodynamic variable was used to explore dynamics of DMPC membranes. The ordering introduced by applying pressure has similar effect to decreased hydration, therefore both approaches are complementary. Covering three orders of magnitude in observation time, the dynamics of native AChE and its complexed counterpart in presence of Huperzin A was investigated in the range from 1 ns to 100 ps. The mean square displacements obtained from the elastic data allowed the determination of activation energies and gave evidence that a hierarchy of motions contributes to the enzymatic activity. Diffusion constants and residence times were extracted from the quasi-elastic broadening. (author) [fr

  12. Low-energy excitations in a low-viscous glass-forming liquid

    Indian Academy of Sciences (India)

    Abstract. Polarized and depolarized low frequency Raman spectra of a liquid mixture, viz. 0·15LiCl–0·85H2O, has been analysed in detail in order to elucidate the temperature and polarization characteristics of quasi-elastic line and Boson peak. The employed fitting procedure shows more convincingly that the Boson peak ...

  13. Proposed ripplon induced weak localization of electrons over liquid helium

    International Nuclear Information System (INIS)

    Dahm, A.J.

    1997-01-01

    Ripplon induced weak localization is proposed for electrons on a liquid helium surface. Ripplon scattering is quasi-elastic, the ripplon are quasi-static relative to the electron velocity, and the relative change in occupation number of the ripplon state in a scattering event is small. Conditions for the observation of ripplon induced weak localization are calculated

  14. Electron interactions with nuclei: Progress report

    International Nuclear Information System (INIS)

    1988-08-01

    This paper contains information on the following topics: inclusive electron scattering; electroexcitation of Δ in nuclei; longitudinal and transverse response in the quasi-elastic region; electron scattering at MIT-Bates; detector development at LEGS; electron scattering at Saclay; intermediate energy nuclear interactions; research and development at CEBAF; and computing facilities

  15. Pramana – Journal of Physics | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Study of diffusivity of acetylene adsorbed in Na-Y zeolite by quasi-elastic neutron scattering (QENS) measurements at temperatures of 300, 325 and 350 K is reported. A model in which the acetylene molecules undergo random-walk diffusion characterized by a Gaussian distribution of jump lengths inside zeolite cages ...

  16. Electromagnetic structure of nuclei

    International Nuclear Information System (INIS)

    Arnold, R.G.

    1986-07-01

    A brief review is given of selected topics in the electromagnetic structure of nucleons and nuclei, including nucleon form factors from both quantum chromodynamics and electron scattering data, measurements of the deuteron and triton form factors, quasi-elastic scattering, and the EMC effect. 47 refs., 13 figs

  17. Polarization of Λ hyperons produced inclusively in νp and anti νp charged current interactions

    International Nuclear Information System (INIS)

    Jones, G.T.; Kennedy, B.W.; O'Neale, S.W.; Barnham, K.W.J.; Clayton, E.F.; Miller, D.B.; Mobayyen, M.M.; Villalobos-Baillie, O.; Corrigan, G.; Myatt, G.; Radojicic, D.; Saitta, B.; Wells, J.; Aderholz, M.; Deck, L.; Schmitz, N.; Settles, R.; Wernhard, K.L.; Wittek, W.

    1985-01-01

    Lambda hyperons from νp and anti np charged current interactions have been analysed for polarization. A significant polarization is observed for Λ particles in the quasi-elastic region for both types of interactions. Part of this polarization is due to the decay of highly polarized Σ(1385) resonances. The results are compared with simple predictions of the quark parton model. (orig.)

  18. On the magnetism of Heisenberg double-layer antiferromagnets

    International Nuclear Information System (INIS)

    Uijen, C.M.J. van.

    1980-01-01

    The author investigates the sublattice magnetization and the susceptibility of the double-layer Heisenberg antiferromagnet K 3 M 2 F 7 by employing the techniques of elastic and quasi-elastic critical magnetic scattering of neutrons. (G.T.H.)

  19. Molecular dynamic analysis of the structure of dendrimers

    Energy Technology Data Exchange (ETDEWEB)

    Canetta, E.; Maino, G. E-mail: maino@bologna.enea.it

    2004-01-01

    We present main results of molecular dynamics simulations that we have carried out in order to investigate structural properties of polyamidoamine (PAMAM) dendrimers. Obtained data confirm the PAMAM dendrimer structure proposed by experiments, performed by means of X-ray scattering (SAXS) and quasi-elastic light scattering (QELS) techniques.

  20. Molecular dynamic analysis of the structure of dendrimers

    International Nuclear Information System (INIS)

    Canetta, E.; Maino, G.

    2004-01-01

    We present main results of molecular dynamics simulations that we have carried out in order to investigate structural properties of polyamidoamine (PAMAM) dendrimers. Obtained data confirm the PAMAM dendrimer structure proposed by experiments, performed by means of X-ray scattering (SAXS) and quasi-elastic light scattering (QELS) techniques

  1. Proceedings of the international conference on dynamical properties of heavy-ion reactions held at the University of the Witwatersrand, v. 1

    International Nuclear Information System (INIS)

    Engelbrecht, C.A.; Lemmer, R.H.; Sellschop, J.P.F.; Toeppfer, C.

    1978-01-01

    The report contains abstracts of the papers delivered at the conference. The abstracts have been grouped into the following chapters: Very heavy nuclei; Deep inelastic reactions and fusion; Resonances; Elastic and quasi-elastic scattering; Atomic physics with heavy ions; Miscellaneous; Post-deadline contributions. Each abstract has been submitted to INIS separately

  2. Orphee reactor experimental equipment

    International Nuclear Information System (INIS)

    1987-01-01

    Experimental equipment around the ORPHEE reactor is presented. The neutron source; and the spectrometers and sample environment (inelastic and quasi-elastic scattering, elastic scattering, spread scattering, small angle scattering) are described. An experiment proposal and reports guide is supplied [fr

  3. Neutron inelastic scattering experiments on the mixed-valent compound YbCuAl

    International Nuclear Information System (INIS)

    Mattens, W.C.M.; de Boer, F.R.; Murani, A.P.; Lander, G.H.

    1979-01-01

    The dynamical susceptibility of YbCuAl has been established by means of time of flight neutron scattering experiments. Non-Korringa behavior of the quasi-elastic line-width has been found and comparison with NMR data will be given

  4. Quasi-one-dimensional magnetic behaviour of the Ising system CsFeCl3.2aq

    NARCIS (Netherlands)

    Kopinga, K.; Steiner, M.; Jonge, de W.J.M.

    1985-01-01

    The magnetic behaviour of the quasi-one-dimensional system CsFeCl3.2aq(aq=H2O, D2O) has been investigated by heat capacity measurements, quasi-elastic neutron scattering and spin-cluster resonance. the experiments demonstrate that below 25K the compound is a very good realisation of an (S=1/2) Ising

  5. Pramana – Journal of Physics | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Keywords. Spin waves; neutron scattering; colossal magnetoresistance. Abstract. The results of inelastic and quasi-elastic neutron scattering investigations on the 40% hole-doped quasi-2D bilayer manganites La1.2Sr1.8Mn2O7 have been reviewed. The complete set of exchange interactions have been determined on the ...

  6. Polarization of Λ hyperons produced inclusively in νp and anti νp charged current interactions

    International Nuclear Information System (INIS)

    Jones, G.T.; Kennedy, B.W.; O'Neale, S.W.; Barnham, K.W.J.; Clayton, E.F.; Miller, D.B.; Mobayyen, M.M.; Villalobos-Baillie, O.; Corrigan, G.; Myatt, G.; Radojicic, D.; Saitta, B.; Wells, J.

    1985-01-01

    Lambda hyperons from νp charged current interactions have been analysed for polarization. A significant polarization is observed for Λ particles in the quasi-elastic region for both types of interactions. Part of this polarization is due to the decay of highly polarized phi(1,385) resonances. The results are compared with simple predictions of the quark parton model. (orig.)

  7. Polarization of Λ hyperons produced inclusively in v p andbar v p charged current interactions

    Science.gov (United States)

    Jones, G. T.; Kennedy, B. W.; O'Neale, S. W.; Böckmann, K.; Gebel, W.; Geich-Gimbel, C.; Nellen, B.; Cooper-Sarkar, A. M.; Grant, A.; Klein, H.; Morrison, D. R. O.; Schmid, P.; Wachsmuth, H.; Barnham, K. W. J.; Clayton, E. F.; Miller, D. B.; Mobayyen, M. M.; Villalobos-Baillie, O.; Aderholz, M.; Deck, L.; Schmitz, N.; Settles, R.; Wernhard, K. L.; Wittek, W.; Corrigan, G.; Myatt, G.; Radojicic, D.; Saitta, B.; Wells, J.

    1985-03-01

    Lambda hyperons from v p andbar v p charged current interactions have been analysed for polarization. A significant polarization is observed for Λ particles in the quasi-elastic region for both types of interactions. Part of this polarization is due to the decay of highly polarized Σ(1385) resonances. The results are compared with simple predictions of the quark parton model.

  8. Determination of the Debye-Waller Factor of hydrogen in Palladium and Palladium Silver alloy

    International Nuclear Information System (INIS)

    Khodabakhsh, R.

    1986-01-01

    The mean square amplitude of the vibrating hydrogen in metals can be determined by using coherent elastic neutron scattering experiments, inelastic one-phonon scattering measurements. To determine the D.W.F. Debye-Waller Factor from the coherent elastic scattering measurements, information about the positions of atoms within the unit is required, and vice versa. The main difficulty concerning the determination of the D.W.F. from the inelastic experiment is in elimination of multi-phonon contribution from the measured spectrum. However, the D.W.F. of hydrogen in palladium has been usually determined by the intensity of the quasi-elastic line. An integration of the measured scattering law S(Q,W) at constant Q, over a certain energy window ΔE, results in the quasi-elastic intensity. To obtain an accurate result, this window has to be chosen large enough to comprise most of the quasi-elastic line, but sufficiently small so that the phonon contributions are small. The MARX spectrometer is ideally constructed for this type of measurement where the window is about +-1 Mev for incident neutron wavelength, =4.115 A. Thus, the quasi-elastic scattering method was considered the best method of determining the D.W.F. of hydrogen in palladium using the MARX spectrometer. However, if the acoustic part overlaps with the quasi-elastic part, one has to obtain the D.W.F. by fitting the data to a quasi-elastic model. The work to be reported here is the investigation of variations of the D.W.F. of hydrogen in Pd and PdAgsub(0.085) with temperature and extension of the available data to as high a temperature as possible. Therefore the integrated intensity of incoherent quasi-elastic neutron scattering by proton in polycrystallin Pd/H and PdAgsub(0.085)/H was investigated as a function of the scattering vector Q. A quasi-harmonic D.W.F. behaviour was observed at elevated temperatures. The observed Debye-Waller Factor depends strongly on the form of the amplitude weighted frequency

  9. Neutron-star mass limit in the bimetric theory of gravitation

    International Nuclear Information System (INIS)

    Caporaso, G.; Brecher, K.

    1977-01-01

    The ''neutron''-star upper mass limit is examined in Rosen's bimetric theory of gravitation. An exact solution, approximate scaling law, and numerical integration of the hydrostatic equilibrium equation show the dependence of the mass limit on the assumed equation of state. As in general relativity, that limit varies roughly as 1/√rho 0 , where rho 0 is the density above which the equation of state becomes ''stiff.'' Unlike general relativity, the stiffer the equation of state, the higher the mass limit. For rho 0 = 2 x 10 14 g/cm 3 and P = (rho - rho 0 ) c 2 , we found M/sub max/ = 81M/sub sun/. This mass is consistent with causality and experimental tests of gravitation and nuclear physics. For dp/drho > c 2 it appears that the upper mass limit can become arbitrarily large

  10. Sensitivity of MODIS 2.1-(micrometers) Channel for Off-Nadir View Angles for Use in Remote Sensing of Aerosol

    Science.gov (United States)

    Gatebe, C. K.; King, M. D.; Tsay, S.-C.; Ji, Q.; Arnold, T.

    2000-01-01

    In this sensitivity study, we examined the ratio technique, the official method for remote sensing of aerosols over land from Moderate Resolution Imaging Spectroradiometer (MODIS) DATA, for view angles from nadir to 65 deg. off-nadir using Cloud Absorption Radiometer (CAR) data collected during the Smoke, Clouds, and Radiation-Brazil (SCAR-B) experiment conducted in 1995. For the data analyzed and for the view angles tested, results seem to suggest that the reflectance (rho)0.47 and (rho)0.67 are predictable from (rho)2.1 using: (rho)0.47 = (rho)2.1/6, which is a slight modification and (rho)0.67 = (rho)2.1/2. These results hold for target viewed from backscattered direction, but not for the forward direction.

  11. Double-spin asymmetries in the cross section of rho sup 0 and phi production at intermediate energies

    CERN Document Server

    Airapetian, A; Akopov, Z; Amarian, M

    2003-01-01

    Double-spin asymmetries in the cross section of electroproduction of rho sup 0 and phi mesons on the proton and deuteron are measured at the HERMES experiment. The photoabsorption asymmetry in exclusive rho sup 0 electroproduction on the proton exhibits a positive tendency. This is consistent with theoretical predictions that the exchange of an object with unnatural parity contributes to exclusive rho sup 0 electroproduction by transverse photons. The photoabsorption asymmetry on the deuteron is found to be consistent with zero. Double-spin asymmetries in rho sup 0 and phi meson electroproduction by quasi-real photons were also found to be consistent with zero; the asymmetry in the case of the phi meson is compatible with a theoretical prediction which involves s anti s knockout from the nucleon. (orig.)

  12. High energy diffraction

    International Nuclear Information System (INIS)

    Berger, C.

    1995-11-01

    Recent experiments on total hadronic cross sections are reviewed together with results on photo- and electroproduction of vector mesons. New data on diffractive deep inelastic scattering shed light on the nature of the pomeron. (orig.)

  13. Strange Twists in Neutral Pion Photo/Electro-Production

    OpenAIRE

    Meißner, Ulf-G.

    1995-01-01

    I review the interesting tale of the electric dipole amplitude in neutral pion photoproduction and the resulting consequences. I also discuss why there is new life related to P--wave multipoles. Electroproduction is briefly touched upon.

  14. Low energy theorems in pion production

    International Nuclear Information System (INIS)

    Holstein, B.R.; Washington Univ., Seattle, WA

    1992-01-01

    Considerable activity-both theoretical and experimental-has recently taken place involving the threshold and near threshold of pion photo- and electroproduction. This activity is herein summarized and a program for future work is outlined

  15. Old soldiers

    International Nuclear Information System (INIS)

    Riordan, M.

    1987-01-01

    The author describes the history of the spectrometer installed at the SLAC 20-GeV-linac and its use from the study of the electroproduction of resonances to the study of the EMC effect with electrons. (HSI).

  16. Cross-sectional evaluation of electrical impedance myography and quantitative ultrasound for the assessment of Duchenne muscular dystrophy in a clinical trial setting.

    Science.gov (United States)

    Rutkove, Seward B; Geisbush, Tom R; Mijailovic, Aleksandar; Shklyar, Irina; Pasternak, Amy; Visyak, Nicole; Wu, Jim S; Zaidman, Craig; Darras, Basil T

    2014-07-01

    Electrical impedance myography and quantitative ultrasound are two noninvasive, painless, and effort-independent approaches for assessing neuromuscular disease. Both techniques have potential to serve as useful biomarkers in clinical trials in Duchenne muscular dystrophy. However, their comparative sensitivity to disease status and how they relate to one another are unknown. We performed a cross-sectional analysis of electrical impedance myography and quantitative ultrasound in 24 healthy boys and 24 with Duchenne muscular dystrophy, aged 2 to 14 years with trained research assistants performing all measurements. Three upper and three lower extremity muscles were studied unilaterally in each child, and the data averaged for each individual. Both electrical impedance myography and quantitative ultrasound differentiated healthy boys from those with Duchenne muscular dystrophy (P Duchenne muscular dystrophy boys (rho = 0.45; P = 0.029), whereas electrical impedance myography did not (rho = -0.31; P = 0.14). However, electrical impedance myography phase correlated with age in healthy boys (rho = 0.51; P = 0.012), whereas quantitative ultrasound did not (rho = -0.021; P = 0.92). In Duchenne muscular dystrophy boys, electrical impedance myography phase correlated with the North Star Ambulatory Assessment (rho = 0.65; P = 0.022); quantitative ultrasound revealed a near-significant association (rho = -0.56; P = 0.060). The two technologies trended toward a moderate correlation with one another in the Duchenne muscular dystrophy cohort but not in the healthy group (rho = -0.40; P = 0.054 and rho = -0.32; P = 0.13, respectively). Electrical impedance myography and quantitative ultrasound are complementary modalities for the assessment of boys with Duchenne muscular dystrophy; further study and application of these two modalities alone or in combination in a longitudinal fashion are warranted. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Functional Mitochondria Are Important for the Effect of Resveratrol

    DEFF Research Database (Denmark)

    Widlund, Anne Lykkegaard; Baral, Kaushal; Dalgaard, Louise Torp

    2017-01-01

    Resveratrol (Resv) is a polyphenol reported to modulate mitochondrial activity. The aim was to use HeLa and 143B cells to characterize the action of Resv on mitochondrial activity, cell size and proliferation using wild type (WT) and Rho 0 cells deficient in mitochondrial DNA. In both HeLa WT and......, but not in Rho 0 when treated with Resv. Overall, the findings presented indicate that functional mitochondria are a prerequisite for cell enlargement by Resv....

  18. The effect of radiation therapy on hemophilic arthropathy

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Jin Oh; Hong, Seong Eon; Kim, Sang Gi; Shin, Dong Oh [School of Medicine, KyungHee University, Seoul (Korea, Republic of)

    2005-06-15

    Repetitive bleeding into the joint space is the cause of debilitative hemophilic arthropathy. To interrupt this process, we treated the hemophilic patients suffering from repetitive joint bleeding with radiation therapy. From 1997 to 2001, a total of 41 joints from 37 hemophilic arthropathy patients were treated with radiation therapy at KyungHee University Hospital. The treated joints were 35 ankles, 3 knees and 3 elbows, respectively. The age of the patients ranged from 4 to 27 years (median age: 11 years). The radiation dose ranged from 900 cGy to 2360 cGy (median dose: 900 cGy). The fraction size was 150 cGy, 180 cGy or 200 cGy. The number of bleeding in one year before and after radiotherapy was compared. There was a tendency of frequent bleeding for the patients younger than 11 ({rho} 0.051) but there was also a tendency for more improvement in this group ({rho} 0.057). The number of joint bleedings was related with joint pain ({rho} 0.012) and joint swelling ({rho} = 0.033) but not with the Arbold-Hilgartner stage ({rho} 0.739),cartilage destruction ({rho} = 0.718) and synovial hypertrophy ({rho} = 0.079). The number of bleeding was reduced in thirty-three cases, and eight cases showed no improvement after radiation therapy. The average number of bleeding in a month was 2.52 before radiotherapy, but this was reduced to 1.4 after radiotherapy ({rho} = 0.017). Radiation therapy was effective for the hemophilia patients with repetitive joint bleeding to decrease the bleeding frequency and to prevent hemophilic arthropathy.

  19. Improving inter-observer variability in the evaluation of ultrasonographic features of polycystic ovaries

    Directory of Open Access Journals (Sweden)

    Leswick David A

    2008-07-01

    Full Text Available Abstract Background We recently reported poor inter-observer agreement in identifying and quantifying individual ultrasonographic features of polycystic ovaries. Our objective was to determine the effect of a training workshop on reducing inter-observer variation in the ultrasonographic evaluation of polycystic ovaries. Methods Transvaginal ultrasound recordings from thirty women with polycystic ovary syndrome (PCOS were evaluated by three radiologists and three reproductive endocrinologists both before and after an ultrasound workshop. The following endpoints were assessed: 1 follicle number per ovary (FNPO, 2 follicle number per single cross-section (FNPS, 3 largest follicle diameter, 4 ovarian volume, 5 follicle distribution pattern and 6 presence of a corpus luteum (CL. Lin's concordance correlation coefficients (rho and kappa statistics for multiple raters (kappa were used to assess level of inter-observer agreement (>0.80 good, 0.60 – 0.80 moderate/fair, Results Following the workshop, inter-observer agreement improved for the evaluation of FNPS (rho = 0.70, delta rho = +0.11, largest follicle diameter (rho = 0.77, delta rho = +0.10, ovarian volume (rho = 0.84, delta rho = +0.12, follicle distribution pattern (kappa = 0.80, delta kappa = +0.21 and presence of a CL (kappa = 0.87, delta kappa = +0.05. No improvement was evident for FNPO (rho = 0.54, delta rho = -0.01. Both radiologists and reproductive endocrinologists demonstrated improvement in scores (p Conclusion Reliability in evaluating ultrasonographic features of polycystic ovaries can be significantly improved following participation in a training workshop. If ultrasonographic evidence of polycystic ovaries is to be used as an objective measure in the diagnosis of PCOS, then standardized training modules should be implemented to unify the approach to evaluating polycystic ovarian morphology.

  20. Current quarks and constituent-classification quarks: some questions and ideas

    International Nuclear Information System (INIS)

    Close, F.E.

    1977-01-01

    A brief introduction is given to the spin dependence of inelastic photo and electroproduction. Parton model predictions of Kuti and Weisskopf are then criticized and a paradox noted in connection with a sum rule of Bjorken. The resolution of this paradox raises several questions concerning the constituent and current quark approaches to resonance excitation. Particular attention is given to current algebra constraints, angular momentum in the nucleon, the x → 1 behavior of inelastic electroproduction, psi production and radiative decays

  1. Exercise radionuclide ventriculographic study of mitral stenosis before and after percutaneous mirtal valvuloplasty

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Do Yun; Shim, Won Heum; Cho, Seung Yun; Kim, Sung Soon; Lee, Woong Ku; Kim, Myeong Jin; Choe, Kyu Ok [Yonsei University, College of Medicine, Seoul (Korea, Republic of); Park, Seung Jung [Asan Medical Center, College of Medicine, University of Ulsan, Seoul (Korea, Republic of)

    1992-11-15

    We performed radionuclide ventriculography before and within 1 week after percutaneous mirtal valvuloplasty (PMV) to evaluate left ventricular (LV) function in 20 patients (2 meals and 17 females, mean age of 38 {+-} 10 years) who were pure mitral stenosis before PMV and less than grade 1 mirtal regurgitation developed after PMV. 9 out of 20 patients had atrial fibrillation and 3 patients developed a small left-to-right shunt (Qp/Qs < 1.5) after PMV. PMV using double-balloon technique resulted in a increase in mitral valve area (0.9 {+-} 0.3 to 2.1 {+-} 0.8cm{sup 2}, {rho} < 0.001) and in rest cardiac output (4.2 {+-} 1.0 to 4.8 {+-} 1.4 L/min, {rho} < 0.005). And also a decrease in mean mitral gradient (16.2 {+-} 7.0 to 5.2 {+-} 3.0 mmHg, {rho} < 0.001) was noted. Comparisons of LV function by supine bicycle exercise radionuclide ventriculography before and after PMV showed no significant changes in rest LV ejection fraction (LVEF, 55.2 {+-} 9.7 to 56.1 {+-} 11.0%, {rho} > 0.05), maximal exercise LVEF (60.9 {+-} 10.3 to 59.3 {+-} 11.1%, {rho} > 0.05), peak ejection rate (2.02 {+-} 0.58 to 2.15 {+-} 0.60 EDV/ses, {rho} > 0.05), and peak filling rate (1.04 {+-} 0.55 to 1.52 {+-} 0.49 EDV/ses, {rho} > 0.05). However, LV end diastolic volume (LVEDV, -29.3 {+-} 19.0 to +3.3 {+-} 32.9%, {rho} < 0.001), stroke volume (SV,-22.0 {+-} 22.0 to +11.2 {+-} 40.0%, {rho} < 0.001), and cardiac output (CO, 64.6 {+-} 54.0 to 100.4 {+-} 69.7%, {rho} < 0.05) with exercise compared to resting values were significantly increased. We conclude that PMV resulted in a significant increase in LVEDV, SV, and CO with exercise, but decreased LV systolic performance and no improvement in diastolic filling.

  2. Prediction of treatment outcome in patients with obsessive-compulsive disorder with Low-Resolution Brain Electromagnetic Tomography: a prospective EEG study

    Directory of Open Access Journals (Sweden)

    Daniela eKrause

    2016-01-01

    Full Text Available The issue of predicting treatment response and identifying, in advance, which patient will profit from treating obsessive-compulsive disorder (OCD seems to be an elusive goal. This prospective study investigated brain electric activity (using Low-Resolution Brain Electromagnetic Tomography (LORETA for the purpose of predicting response to treatment. Forty-one unmedicated patients with a DSM-IV diagnosis of OCD were included. A resting 32-channel EEG was obtained from each participant before and after ten weeks of standardized treatment with sertraline and behavioral therapy. LORETA was used to localize the sources of brain electrical activity. At week ten, patients were divided into responders and non-responders (according to a reduction of symptom severity > 50% on the Y-BOCS. LORETA analysis revealed that at baseline responders showed compared to non-responders a significantly lower brain electric activity within the beta 1 (t=2.86, p<0.05, 2 (t=2.81, p<0.05 and 3 (t=2.76, p<0.05 frequency bands and ROI analysis confirmed a reduced activity in alpha 2 (t=2.06, p<0.05 in the anterior cingulate cortex (ACC. When baseline LORETA data were compared to follow-up data, the analysis showed in the responder group a significantly lower brain electrical resting activity in the beta 1 (t=3.17. p<0.05 and beta 3 (t=3.11. p<0.05 frequency bands and equally for the ROI analysis of the orbitofrontal cortex (OFC in the alpha 2 (t=2.15. p<0.05 frequency band. In the group of non-responders the opposite results were found. In addition, a positive correlation between frequency alpha 2 (rho=0.40, p=0.010, beta 3 (rho=0.42, p=0.006, delta (rho=0.33, p=0.038, theta (rho=0.34, p=0.031, alpha 1 (rho=0.38, p=0.015 and beta1 (rho=0.34, p=0.028 of the OFC and the bands delta (rho=0.33, p=0.035, alpha 1 (rho=0.36, p=0.019, alpha 2 (rho=0.34, p=0.031 and beta 3 (rho=0.38, p=0.015 of the ACC with a reduction of the Y-BOCS scores was identified.Our results suggest that

  3. Study of excitation energy sharing in heavy ion collisions as a function of their inelasticity

    International Nuclear Information System (INIS)

    Lott, B.

    1986-01-01

    The excitation energy sharing between the fragments of a heavy ion collision has been studied for quasi-elastic and deep inelastic mechanisms. A 32 S beam of 232 MeV incident energy has been used to bombard several targets (S, 58 Ni, 93 Nb). The evaporated charged particle multiplicities have been measured by inclusive measurements of the projectile-like nuclei and exclusive measurements of the two final nuclei. Evaporation calculations using the Hauser-Feshbach formalism allows us to deduce from the multiplicity measurements the projectile-like excitation energy. These results are compatible with the assumption of an equal sharing of excitation energies for quasi-elastic reaction products, and with the assumption of a mass ratio sharing for fully relaxed reaction products. Limiting values for the relaxation time of this mode have been deduced and are in agreement with predictions from the model developed by Randrup [fr

  4. Toward a consistent RHA-RPA

    International Nuclear Information System (INIS)

    Shepard, J.R.

    1991-01-01

    The authors examine the RPA based on a relativistic Hartree approximation description for nuclear ground states. This model includes contributions from the negative energy sea at the 1-loop level. They emphasize consistency between the treatment of the ground state and the RPA. This consistency is important in the description of low-lying collective levels but less important for the longitudinal (e, e') quasi-elastic response. They also study the effect of imposing a 3-momentum cutoff on negative energy sea contributions. A cutoff of twice the nucleon mass improves agreement with observed spin orbit splittings in nuclei compared to the standard infinite cutoff results, an effect traceable to the fact that imposing the cutoff reduces m*/m. The cutoff is much less important than consistency in the description of low-lying collective levels. The cutoff model provides excellent agreement with quasi-elastic (e, e') data

  5. Neutron-scattering studies of the S=2 antiferromagnetic chain MnCl sub 3 (C sub 1 sub 0 D sub 8 N sub 2)

    CERN Document Server

    Granroth, G E; Coldea, R; Eccleston, R S; Ward, B H; Talham, D R; Meisel, M W

    2002-01-01

    Quasi-elastic and inelastic neutron scattering studies of the quasi-one-dimensional S=2 antiferromagnet MnCl sub 3 (C sub 1 sub 0 D sub 8 N sub 2) are reported. The quasi-elastic measurements exhibit a broad peak at Q approx 0.69 A sup - sup 1 , which is consistent with short-range antiferromagnetic coupling between neighboring Mn sup 3 sup + ions. Inelastic experiments, at 150 mK and Q=0.70 A sup - sup 1 , reveal decreased magnetic scattering at energies less than 0.2 meV when compared to similar studies at 20 K. These results provide microscopic evidence for the presence of a Haldane gap and are consistent with the bulk magnetization measurements of Granroth et al. (orig.)

  6. Neutron-scattering studies of the S=2 antiferromagnetic chain MnCl3(C10D8N2)

    International Nuclear Information System (INIS)

    Granroth, G.E.; Nagler, S.E.; Coldea, R.; Eccleston, R.S.; Ward, B.H.; Talham, D.R.; Meisel, M.W.

    2002-01-01

    Quasi-elastic and inelastic neutron scattering studies of the quasi-one-dimensional S=2 antiferromagnet MnCl 3 (C 10 D 8 N 2 ) are reported. The quasi-elastic measurements exhibit a broad peak at Q∼0.69 A -1 , which is consistent with short-range antiferromagnetic coupling between neighboring Mn 3+ ions. Inelastic experiments, at 150 mK and Q=0.70 A -1 , reveal decreased magnetic scattering at energies less than 0.2 meV when compared to similar studies at 20 K. These results provide microscopic evidence for the presence of a Haldane gap and are consistent with the bulk magnetization measurements of Granroth et al. (orig.)

  7. Fuzzy barrier distributions

    International Nuclear Information System (INIS)

    Piasecki, E.

    2009-01-01

    Heavy-ion collisions often produce a fusion barrier distribution with structures displaying a fingerprint of couplings to highly collective excitations [1]. Basically the same distribution can be obtained from large-angle quasi-elastic scattering, though here the role of the many weak direct-reaction channels is unclear. For 2 0N e + 9 0Z r we have observed the barrier structures expected for the highly deformed neon projectile, but for 2 0N e + 9 2Z r we find completely smooth distribution (see Fig.1). We find that transfer channels in these systems are of similar strength but single particle excitations are significantly stronger in the latter case. They apparently reduce the 'resolving power' of the quasi-elastic channel, what leads to smeared out, or 'fuzzy' barrier distribution. This is the first case when such a phenomenon has been observed.(author)

  8. Spectra of fast protons produced in the pA → pX reaction at the angle of 62 mrad

    International Nuclear Information System (INIS)

    Barabash, L.Z.; Buklej, A.E.; Gavrilov, V.B.

    1982-01-01

    Within the framework of a program of investigations into yields of secondary particles form internal targets of an accelerator obtained were experimetnal data on inclusive production of protons in pA interactions at 62 mradn angle at initial momenta of 4.0; 6.6; 9.5 GeV/c. The data obtained on differential cross sections of proton yields are tabulated. A- and t-dependences of quasi-elastic proton scattering with nuclei are discussed. A-dependence of cross sections of inelastic quasi-free reactions both in the region of isobar production and on the left of this region within the errors is the same as for quasi-elastic peak, α approximately 0.45. This α value is markedly less than a value characteristic of the A-dependence of total cross sections

  9. Transfer and breakup reactions at intermediate energies

    International Nuclear Information System (INIS)

    Stokstad, R.G.

    1986-04-01

    The origin of the quasi-elastic peak in peripheral heavy-ion reactions is discussed in terms of inelastic scattering and transfer reactions to unbound states of the primary projectile-like fragment. The situation is analogous to the use of reverse kinematics in fusion reactions, a technique in which the object of study is moving with nearly the beam velocity. It appears that several important features of the quasi-elastic peak may be explained by this approach. Projectile-breakup reactions have attractive features for the study of nuclear structure. They may also be used to determine the partition of excitation energy in peripheral reactions. At intermediate energies, neutron-pickup reactions leading to four-body final states become important. Examples of experiments are presented that illustrate these points. 15 refs., 14 figs

  10. Studies of molecular dynamics with neutron scattering techniques. Part of a coordinated programme on neutron scattering techniques

    International Nuclear Information System (INIS)

    Vinhas, L.A.

    1980-05-01

    Molecular dynamics was studied in samples of tert-butanol, cyclohexanol and methanol, using neutron inelastic and quasi-elastic techniques. The frequency spectra of cyclohexanol in crystalline phase were interpreted by assigning individual energy peaks to hindered rotation of molecules, lattice vibration, hydrogen bond stretching and ring bending modes. Neutron quasi-elastic scattering measurements permitted the testing of models for molecular diffusion as a function of temperature. The interpretation of neutron incoherent inelastic scattering on methanol indicated the different modes of molecular dynamics in this material; individual inelastic peaks in the spectra could be assigned to vibrations of crystalline lattice, stretching of hydrogen bond and vibrational and torsional modes of CH 3 OH molecule. The results of the experimental work on tertbutanol indicate two distinct modes of motion in this material: individual molecular librations are superposed to a cooperative rotation diffusion which occurs both in solid and in liquid state

  11. Measurement of the Electric Form Factor of the Neutron at MAMI

    International Nuclear Information System (INIS)

    Seimetz, M.

    2005-01-01

    At the Mainz Microtron the electric form factor of the neutron, G E,n , has been measured in two kinds of double polarisation experiments. The most recent results have been obtained by recoil polarimetry from the quasi-elastic D(e->,e ' n->)p reaction at squared four-momentum transfers Q 2 =0.3,0.6, and 0.8(GeV/c) 2 . A further data point at 0.67(GeV/c) 2 has been extracted from quasi-elastic scattering of polarised electrons on H->e3. We present the methods and results of our experiments as well as an overview on the precise G E,n data available at present

  12. Dynamics and denaturation of a protein. Simulations and neutron scattering on staphylococcus nuclease

    International Nuclear Information System (INIS)

    Goupil-Lamy, Anne

    1997-01-01

    This research thesis reports simulations and experiments of inelastic scattering on the whole frequency spectrum to analyse the vibrations of the staphylococcus nuclease and its fragment, in order to study protein folding. Based on these experiments, information on eigenvectors which describe vibration modes can be directly obtained. Inelastic intensities are indeed fully determined by nuclear cross sections and the mean square displacement of each atom. Some experimentally noticed peaks are then explained by calculating a theoretical spectrum from an analysis of normal modes. The studied fragment is made of 136 c-terminal residues. The fragment structure obtained by molecular dynamics simulation is compared with available experimental data. Then, experiments of neutron scattering on the nuclease of staphylococcus and its fragment have been performed. Quasi elastic scattering spectra have been measured. The author then used simulations to try to reproduce the quasi-elastic spectrum. Experiments of inelastic scattering have then been performed [fr

  13. The G0 backangle measurements

    International Nuclear Information System (INIS)

    S. Kox

    2007-01-01

    This contribution presents the status, at the time of this conference, of the second phase of the G0 experiment. This experiment is being performed in Hall C at Jefferson Laboratory. It measures PV asymmetries in elastic electron-proton and quasi-elastic electron-deuteron scattering. Details of the experimental setup are given, together with the first data collected in 2006 at backward angles

  14. Proceedings of the 12. International Symposium on Nuclear Physics - Heavy-Ion Collisions and Nuclear Fission - organized by the Technical University of Dresden, November 22-26, 1982 in Gaussig (GDR)

    International Nuclear Information System (INIS)

    Reif, R.; Teichert, J.

    1982-12-01

    The following problems in experimental and theoretical investigations of heavy-ion reactions and the dynamics of nuclear fission processes are discussed: (1) emission of fast light particles in heavy-ion collisions, preequilibrium effects; (2) dynamics of deep inelastic heavy-ion reactions; (3) selected topics in quasi-elastic heavy-ion collisions; and (4) collective transport theory for fission, cross sections and neutron spectra of fission. Problems of neutron induced reactions and nuclear data evaluation are also covered. (author)

  15. Low energy positron interactions with uracil—Total scattering, positronium formation, and differential elastic scattering cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, E. K.; Boadle, R. A.; Machacek, J. R.; Makochekanwa, C.; Sullivan, J. P. [ARC Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra 0200 (Australia); Chiari, L. [ARC Centre for Antimatter-Matter Studies, Flinders University, GPO Box 2100, Adelaide, 5001 SA (Australia); Buckman, S. J., E-mail: Stephen.buckman@anu.edu.au [ARC Centre for Antimatter-Matter Studies, Research School of Physics and Engineering, The Australian National University, Canberra 0200 (Australia); Institute of Mathematical Sciences, University of Malaya, Kuala Lumpur (Malaysia); Brunger, M. J. [ARC Centre for Antimatter-Matter Studies, Flinders University, GPO Box 2100, Adelaide, 5001 SA (Australia); Institute of Mathematical Sciences, University of Malaya, Kuala Lumpur (Malaysia); Garcia, G. [Instituto de Fısica Fundamental, Consejo Superior de Investigationes Cientıficas (CSIC), Serrano 113-bis, E-28006 Madrid (Spain); Blanco, F. [Departamento de Fısica Atomica, Molecular y Nuclear, Universidad Complutense de Madrid, E-28040 Madrid (Spain); Ingolfsson, O. [Department of Chemistry, Science Institute, University of Iceland, Reykjavík 107 (Iceland)

    2014-07-21

    Measurements of the grand total and total positronium formation cross sections for positron scattering from uracil have been performed for energies between 1 and 180 eV, using a trap-based beam apparatus. Angular, quasi-elastic differential cross section measurements at 1, 3, 5, 10, and 20 eV are also presented and discussed. These measurements are compared to existing experimental results and theoretical calculations, including our own calculations using a variant of the independent atom approach.

  16. http://www.tkea.com.ua/tkea/2008/6_2008/pdf/12.zip

    Directory of Open Access Journals (Sweden)

    Kavetskyy T. S.

    2008-12-01

    Full Text Available It is established radiation-induced decreasing in fragility of structural network takes place for γ-irradiated sample of Ge15,8As21S63,2 chalcogenide glass. It is concluded on the basis of the results obtained that radiation modification of chalcogenide glass leads to the rigidity of its matrix, and the vibrational (boson contribution in the low-frequency spectral region is dominatе on the relaxation quasi-elastic scattering.

  17. Measurement of Neutrino Induced, Charged Current, Charged Pion Production

    Energy Technology Data Exchange (ETDEWEB)

    Wilking, Michael Joseph [Univ. of Colorado, Boulder, CO (United States)

    2009-05-01

    Neutrinos are among the least understood particles in the standard model of particle physics. At neutrino energies in the 1 GeV range, neutrino properties are typically determined by observing the outgoing charged lepton produced in a charged current quasi-elastic interactions. The largest charged current background to these measurements comes from charged current pion production interactions, for which there is very little available data.

  18. Further evidence of a liquid-liquid transition in interfacial water

    International Nuclear Information System (INIS)

    Zanotti, J-M; Bellissent-Funel, M C; Chen, S-H; Kolesnikov, A I

    2006-01-01

    In a previous paper we combined calorimetric, diffraction and high-resolution quasi-elastic neutron scattering data to show that after exhibiting a glass transition at 165 K, interfacial water experiences a first order liquid-liquid transition at 240 K from a low-density to a high-density liquid. Here we present further evidence of these transitions obtained by high-energy inelastic neutron scattering

  19. Recent applications of the Boltzmann master equation to heavy ion precompound decay phenomena

    International Nuclear Information System (INIS)

    Blann, M.; Remington, B.A.

    1988-06-01

    The Boltzmann master equation (BME) is described and used as a tool to interpret preequilibrium neutron emission from heavy ion collisions gated on evaporation residue or fission fragments. The same approach is used to interpret neutron spectra gated on deep inelastic and quasi-elastic heavy ion collisions. Less successful applications of BME to proton inclusive data with 40 MeV/u incident 12 C ions are presented, and improvements required in the exciton injection term are discussed

  20. New results from dissipative diabatic dynamics and nuclear elastoplasticity

    International Nuclear Information System (INIS)

    Noerenberg, W.; Technische Hochschule Darmstadt

    1986-10-01

    I present new results about dissipative diabatic dynamics and nuclear elastoplasticity, in particular on a self-consistent diabatic formulation, on first numerical calculations of dissipative diabatic dynamics in two collective degrees of freedom, on quasi-elastic recoil in central nucleus-nucleus collisions, on the diabatic hindrance of fusion reactions and on the diabatic emission of nucleons in central nucleus-nucleus collisions. (orig./HSI)

  1. Recent Results from MINERvA

    Energy Technology Data Exchange (ETDEWEB)

    Fields, Laura [Fermilab

    2016-12-21

    The MINERvA collaboration is currently engaged in a broad program of neutrino-nucleus interaction measurements. Several recent measurements of interest to the accelerator-based oscillation community are presented. These include measurements of quasi-elastic scattering, diffractive pion production, kaon production and comparisons of interaction cross sections across nuclei. A new measurement of the NuMI neutrino beam flux that incorporates both external hadro-production data and MINERvA detector data is also presented.

  2. Heavy ion reactions in the transition region

    International Nuclear Information System (INIS)

    Hendrie, D.L.

    1977-11-01

    Evidence is given for a serious and systematic failure of the DWBA to predict the cross sections for single nucleon transfers induced by heavy ions above about 10 MeV/Nucleon beam energies. This is perhaps related to a coherent coupling to an increasing cross section to the quasi-elastic continuum, which also shows an anomalous energy dependence at about the same energy

  3. The threshold anomaly in the interaction of s-d shell nuclei

    International Nuclear Information System (INIS)

    Bilwes, B.

    1990-01-01

    The energy dependence of the potential near the Coulomb barrier is studied by precise measurements of elastic scattering and quasi elastic reactions between s-d shell nuclei. The analyses with semi-microscopic (M3Y-folding model) and microscopic (closure approximation model) potentials allow us to demonstrate the generality of the threshold anomaly and the ability of these models to well reproduce the experimental data

  4. Electrodisintegration of few body systems at SLAC and the Y scaling approach

    International Nuclear Information System (INIS)

    Meziani, Z.E.

    1986-10-01

    It is proposed that extraction of the scaling function F(y) from the transverse and longitudinal response functions in inclusive quasi-elastic electron scattering from 3 He and 4 He is a powerful method to either study the validity regime of the impulse approximation by allowing the access to the high nucleon momentum components in these nuclei, or the electromagnetic properties of bound nucleons. 19 refs., 4 figs

  5. Effect of secondary rescattering in the reaction D(. pi. /sup -/,. pi. /sup -/p)n at high energies. [Secondary rescattering, angular distributions

    Energy Technology Data Exchange (ETDEWEB)

    Kolybasov, V M; Ksenzov, V G [Gosudarstvennyj Komitet po Ispol' zovaniyu Atomnoj Ehnergii SSSR, Moscow. Inst. Teoreticheskoj i Ehksperimental' noj Fiziki

    1975-01-01

    The D(..pi../sup -/,..pi../sup -/p)n reaction is theoretically treated. Besides simple quasi-elastic knocking out, account was taken of diagrams of secondary rescattering of reaction products. Momentum and neutron polar angle distributions, as well as the Treyman-Young angular distribution, are compared with experimental data at 1 GeV. The behaviour of various distributions of individual diagrams is studied, and their response to the mechanism of the reaction is investigated with a methodological purpose.

  6. Knock-out reactions

    International Nuclear Information System (INIS)

    de Forest, T. Jr.

    1977-01-01

    It is pointed out that the primary motivation for performing high energy single nucleon knock-out reactions is based on the concept of quasi-elastic scattering. The validity of and corrections to the partial wave impulse approximation and kinematical invariance of knock-out reactions and tests of the reaction mechanism are treated. The effect of distortions on the momentum distribution in the effective momentum approximation for given parameters are plotted. 12 references

  7. Investigation of the circular random walk motion in nematic material

    International Nuclear Information System (INIS)

    Bata, L.; Tuettoe, I.

    1976-12-01

    The molecular dynamics of liquid crystalline mesophase is investigated. A new theoretical model describing the rotational motion on a sphere with two relaxation times is worked out. Quasi-elastic neutron spectra have been measured on aligned di-butyl derivative of phenylbenzoyl azoxy-benzoate at different temperatures. The results are interpreted on the basis of the author's model and the non-equivalence of the hydrogen atom is shown. (Sz.N.Z.)

  8. Recent Results from MINERvA

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Jonathan [Santa Maria U., Valparaiso

    2014-09-01

    MINERvA (Main INjector ExpeRiment for v-A) is a few-GeV neutrino nucleus scattering experiment at Fermilab using various nuclei as targets. The experiment provides measurements of neutrino and anti-neutrino cross sections off of nuclear targets which are important for neutrino oscillation experiments and the probing of the nuclear medium.Presented are recent results from MINERvA on quasi-elastic, inclusive charged-current neutrino scattering, and pion production processes.

  9. Studies of the dynamic properties of materials using neutron scattering

    International Nuclear Information System (INIS)

    Lovesey, S.W.; Windsor, C.G.

    1985-09-01

    The dynamic properties of materials using the neutron scattering technique is reviewed. The basic properties of both nuclear scattering and magnetic scattering are summarized. The experimental methods used in neutron scattering are described, along with access to neutron sources, and neutron inelastic instruments. Applied materials science using inelastic neutron scattering; rotational tunnelling of a methyl group; molecular diffusion from quasi-elastic scattering; and the diffusion of colloidal particles and poly-nuclear complexes; are also briefly discussed. (U.K.)

  10. Study of the (p,px) reaction at 156 MeV on some light nuclei

    International Nuclear Information System (INIS)

    Bachelier, Daniel

    1971-01-01

    This research thesis reports the study of four quasi-elastic diffusion reactions of (p,px) type at 156 MeV: 6 Li(p,pd ) 4 He, 6 Li(p,pr) 3 H, 7 Li(p,pt) 4 He and 12 C(p,pd) 10 B. The objectives were to check the quasi-elastic character of these reactions and to describe them by pulse approximations with plane waves, to study their selection rules and to understand their angular correlations with respect to momentum distribution in the target nucleus of ejected substructures (clusters), to compare the probabilities of different configurations corresponding to different models, and, in the case of carbon, to compare the experimental energy spectrum with theoretical predictions. After a discussion of the theoretical expression of the cross-section of a quasi-elastic reaction, and a presentation of the different nuclear models which have been used for this reaction type, the author reports the study of the kinematics of these reactions by defining the conditions under which the knock-out mechanism is promoted. The author describes the beam, targets, detectors and electronic devices used for this study. He addresses the methods used to identify events and to analyse results. Experimental results are presented and compared with theoretical results and with other published experimental results

  11. Prospects in coincidence experiments

    International Nuclear Information System (INIS)

    Laget, J.M.

    1984-01-01

    The sensitivity of virtual photons to the local variations of the charge and magnetization densities is exploited to study the short-range part of the nucleon-nucleon interaction inside the nucleus. The possibility of varying energy, squared mass and longitudinal polarization of the photons independently enables us to disentangle the mechanisms related to the internal structure of the nucleon (e.g. quark interchange) and the contribution due to meson exchange. Coincidence experiments of the type (e,e'N) and (e,e'NN) are performed to suppress the meson contribution to the longitudinal part of the quasi-elastic peak. Four typical examples of coincidence experiments induced by virtual photons are discussed: experiments (1) on the spectroscopic structure of the quasi-elastic peak and the problem of deep lying hole states; (2) on the structure of the continuum; (3) on the low energy side of the quasi-elastic peak; and finally a three-arm coincidence experiment. (Auth.)