Study of Charm Baryons with the BaBar Experiment

International Nuclear Information System (INIS)

Petersen, Brian Aa.

2006-01-01

The authors report on several studies of charm baryon production and decays by the BABAR collaboration. They confirm previous observations of the Ξ' c 0/+ , Ξ c (2980) + and Ξ c (3077) + baryons, measure branching ratios for Cabibbo-suppressed Λ c + decays and use baryon decays to study the properties of the light-quark baryons, (Omega) - and Ξ(1690) 0

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...

Spectroscopy of doubly charmed baryons from lattice QCD

Energy Technology Data Exchange (ETDEWEB)

Padmanath, M. [Univ. of Graz, Graz (Austria); Edwards, Robert G. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Mathur, Nilmani [Tata Inst. of Fundamental Research, Mumbai (India); Peardon, Michael [Trinity College, Dublin (Ireland)

2015-05-06

This study presents the ground and excited state spectra of doubly charmed baryons from lattice QCD with dynamical quark fields. Calculations are performed on anisotropic lattices of size 16³ × 128, with inverse spacing in temporal direction a_t⁻¹=5.67(4) GeV and with a pion mass of about 390 MeV. A large set of baryonic operators that respect the symmetries of the lattice yet which retain a memory of their continuum analogues are used. These operators transform as irreducible representations of SU(3)_F symmetry for flavor, SU(4) symmetry for Dirac spins of quarks and O(3) for spatial symmetry. The distillation method is utilized to generate baryon correlation functions which are analyzed using the variational fitting method to extract excited states. The lattice spectra obtained have baryonic states with well-defined total spins up to 7/2 and the pattern of low-lying states does not support the diquark picture for doubly charmed baryons. On the contrary the calculated spectra are remarkably similar to the expectations from models with an SU(6)×O(3) symmetry. Various spin-dependent energy splittings between the extracted states are also evaluated.

Excited state mass spectra of singly charmed baryons

Energy Technology Data Exchange (ETDEWEB)

Shah, Zalak; Kumar Rai, Ajay [Sardar Vallabhbhai National Institute of Technology, Department of Applied Physics, Surat, Gujarat (India); Thakkar, Kaushal [GIDC Degree Engineering College, Department of Applied Sciences and Humanities, Abrama (India); Vinodkumar, P.C. [Sardar Patel University, Department of Physics, V.V. Nagar (India)

2016-10-15

Mass spectra of excited states of the singly charmed baryons are calculated using the hypercentral description of the three-body system. The baryons consist of a charm quark and light quarks (u, d and s) are studied in the framework of QCD motivated constituent quark model. The form of the confinement potential is hyper-Coloumb plus power potential with potential index ν, varying from 0.5 to 2.0. The first-order correction to the confinement potential is also incorporated in this approach. The radial as well as orbital excited state masses of Σ{sub c}{sup ++}, Σ{sub c}{sup +}, Σ{sub c}{sup 0}, Ξ{sub c}{sup +}, Ξ{sub c}{sup 0}, Λ{sub c}{sup +}, Ω{sub c}{sup 0} baryons, are reported in this paper. We have incorporated spin-spin, spin-orbit and tensor interactions perturbatively in the present study. The semi-electronic decay of Ω{sub c} and Ξ{sub c} are also calculated using the spectroscopic parameters of these baryons. The computed results are compared with other theoretical predictions as well as with the available experimental observations. We also construct the Regge trajectory in (n{sub r},M{sup 2}) and (J,M{sup 2}) planes for these baryons. (orig.)

Cross-section measurement for quasielastic production of charmed baryons in nu N interactions

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; Lavina, L S; 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 quasielastic production of charmed baryons in charged- current interactions of neutrinos with the nuclear emulsion target of CHORUS is presented. In a sample of about 46 000 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 the topological and kinematical characteristics of quasielastic 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 quasielastic production of a charmed baryon with an estimated background of 1.7 events was obtained. At the average neutrino energy of 27 GeV the cross-section for the total quasielastic production of charmed baryons relative to the nu N charged-current cross-section was measured to be sigma (QE)/ sigma (CC)=(0.23/sub -0.06//sup +0.12 /(stat)/sub -0.03//sup + /0/sup ....

Strange and charm baryon masses with two flavors of dynamical twisted mass fermions

Energy Technology Data Exchange (ETDEWEB)

Alexandrou, C. [Univ. of Cyprus, Nicosia (Cyprus). Dept. of Physics; Cyprus Institute, Nicosia (Cyprus). Computation-Based Science and Technology Research Center; Carbonell, J. [CEA-Saclay, Gif-sur-Yvette (France). IRFU/Service de Physique Nucleaire; Christaras, D.; Gravina, M. [Univ. of Cyprus, Nicosia (Cyprus). Dept. of Physics; Drach, V. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Papinutto, M. [UFJ/CNRS/IN2P3, Grenoble (France). Laboratoire de Physique Subatomique et Cosmologie; Universidad Autonoma de Madrid (Spain). Dept. de Fisica Teorica; Universidad Autonoma de Madrid UAM/CSIC (Spain). Inst. de Fisica Teorica

2012-10-15

The masses of the low-lying strange and charm baryons are evaluated using two degenerate flavors of twisted mass sea quarks for pion masses in the range of about 260 MeV to 450 MeV. The strange and charm valence quark masses are tuned to reproduce the mass of the kaon and D-meson at the physical point. The tree-level Symanzik improved gauge action is employed. We use three values of the lattice spacing, corresponding to {beta}=3.9, {beta}=4.05 and {beta}=4.2 with r{sub 0}/a=5.22(2), r{sub 0}/a=6.61(3) and r{sub 0}/a=8.31(5) respectively. We examine the dependence of the strange and charm baryons on the lattice spacing and strange and charm quark masses. The pion mass dependence is studied and physical results are obtained using heavy baryon chiral perturbation theory to extrapolate to the physical point.

Spectroscopy of doubly and triply-charmed baryons from lattice QCD

Energy Technology Data Exchange (ETDEWEB)

Padmanath, M. [Tata Institute; Edwards, Robert G. [JLAB; Mathur, Nilmani [Tata Institute; Peardon, Michael [Trinity College, Dublin

2013-11-01

We present the ground and excited state spectra of doubly and triply-charmed baryons by using lattice QCD with dynamical clover fermions. A large set of baryonic operators that respect the symmetries of the lattice and are obtained after subduction from their continuum analogues are utilized. Using novel computational techniques correlation functions of these operators are generated and the variational method is exploited to extract excited states. The lattice spectra that we obtain have baryonic states with well-defined total spins up to 7/2 and the low lying states remarkably resemble the expectations of quantum numbers from SU(6) Ⓧ O(3) symmetry. Various energy splittings between the extracted states, including splittings due to hyperfine as well as spin-orbit coupling, are considered and those are also compared against similar energy splittings at other quark masses. Using those splittings for doubly-charmed baryons, and taking input of experimental Bc meson mass, we predict the mass splittings of B*c-Bc to be about 80 ± 8 MeV and mΩccb=8050±10 MeV.

Search for Popcorn Mesons in Events with Two Charmed Baryons

Energy Technology Data Exchange (ETDEWEB)

Hartfiel, Brandon; /SLAC

2006-07-07

The physics of this note is divided into two parts. The first part measures the {Lambda}{sub c} {yields} {pi}kp continuum momentum spectrum at a center of mass energy of 10.54 GeV/c. The data sample consists of 15,400 {Lambda}{sub c} baryons from 9.46 fb{sup -1} of integrated luminosity. With more than 13 times more data than the best previous measurement, we are able to exclude some of the simpler, one parameter fragmentation functions. In the second part, we add the {Lambda}{sub c} {yields} K{sup 0}p mode, and look for events with a {Lambda}{sub c}{sup +} and a {bar {Lambda}}{sub c}{sup -} in order to look for ''popcorn'' mesons formed between the baryon and antibaryon. We add on-resonance data, with a kinematic cut to eliminate background from B decays, as well as BaBar run 3 and 4 data to increase the total data size to 219.70 fb{sup -1}. We find 619 events after background subtraction. After a subtraction of 1.06 {+-} .09 charged pions coming from decays of known resonances to {Lambda}{sub c} + {eta}{pi}, we are left with 2.63 {+-} .21 additional charged pions in each of these events. This is significantly higher than the .5 popcorn mesons per baryon pair used in the current tuning of Pythia 6.2, the most widely used Monte Carlo generator. The extra mesons we find appear to be the first direct evidence of popcorn mesons, although some of them could be arising from hypothetical unresolved, unobserved charmed baryon resonances contributing decay mesons to our data. To contribute a significant fraction, this hypothesis requires a large number of such broad unresolved states and seems unlikely, but can not be completely excluded.

Production of doubly charmed baryons nearly at rest

Energy Technology Data Exchange (ETDEWEB)

Groote, Stefan; Koshkarev, Sergey [University of Tartu, Institute of Physics, Tartu (Estonia)

2017-08-15

We investigate the production cross sections, momentum distributions and rapidity distributions for doubly charmed baryons which according to the intrinsic heavy quark mechanism are produced nearly at rest. These events should be measurable at fixed-target experiments like STAR rate at RHIC and AFTER rate at LHC. (orig.)

Charmed hadrons in nuclear medium

International Nuclear Information System (INIS)

Tolos, L.; Gamermann, D.; Molina, R.; Nieves, J.; Oset, E.; Garcia-Recio, C.; Ramos, A.

2010-01-01

We study the properties of charmed hadrons in dense matter within a coupled-channel approach which accounts for Pauli blocking effects and meson self-energies in a self-consistent manner. We analyze the behaviour in this dense environment of dynamically-generated baryonic resonances as well as the open-charm meson spectral functions. We discuss the implications of the in-medium properties of open-charm mesons on the D s0 (2317) and the predicted X(3700) scalar resonances. (authors)

Charmed baryon production in hadronic collisions

International Nuclear Information System (INIS)

Boreskov, K.G.; Kaidalov, A.B.

1982-01-01

Quantitative description of charmed baryon production in pp and πp collisions is obtained in the framework of the soft, peripheral quark-gluon approach. The quark-gluon model, based on the topological expansion, is used for determination of the planar part of the multiperipheral diagrams. The parameters of the D*-D** Regge trajectories and residues are estimated in this model. The total contribution of the peripheral mechanism is calculated by substitution of this planar part to the cylinder-type multiperipheral diagram with π-meson exchange. The energy dependence, absolute value of the inclusive cross section for #betta#sub(c) production and its xsub(F) and psub(perpendicular)-distributions (where xsub(F) is the Feynman variable and psub(perpendicular) is transverse momentum) are calculated and found to be in an agreement with experimental data. Connection with orher models of charm production is discussed

Exotic charmed baryon production in ultrarelativistic heavy ion collisions

International Nuclear Information System (INIS)

Zimanyi, J.; Biro, T.S.; Levai, P.

1993-01-01

The authors investigate multi-heavy baryon formation in Au + Au collision using an extended version of the combinatoric break up model for rehadronization. A penalty factor, p, is introduced to characterize the coalescence probability of a light quark with a heavy one. At LHC energy large production rate is found for certain multi-heavy baryons and mesons such as Ω ccc , Ξ cc , J/Ψ and suppression for Λ c , D. They speculate also on the possible existence of a heavy bottom-charm six-quark baryon. A semiclassical and a gaussian estimate reveal that the octet-octet bbb-cc configuration can be energetically favored with respect to the singlet-singlet one

Hyperon AND Hyperon Resonance Properties From Charm Baryon Decays At BaBar

Energy Technology Data Exchange (ETDEWEB)

Ziegler, Veronique; /Iowa U.

2007-07-03

This report describes studies of hyperons and hyperon resonances produced in charm baryon decays at BABAR. Using two-body decays of the {Xi}{sub c}{sup 0} and {Omega}{sub c}{sup 0}, it is shown, for the first time, that the spin of the {omega}{sup -} is 3/2. The {Omega}{sup -} analysis procedures are extended to three-body final states and properties of the {Xi}(1690){sup 0} are extracted from a detailed isobar model analysis of the {Lambda}{sub c}{sup +} {yields} {Lambda}{bar K}{sup 0}K{sup +} Dalitz plot. The mass and width values of the {Xi}(1690){sup 0} are measured with much greater precision than attained previously. The hypothesis that the spin of the {Xi}(1690) resonance is 1/2 yields an excellent description of the data, while spin values 3/2 and 5/2 are disfavored. The {Lambda}a{sub 0}(980){sup +} decay mode of the {Lambda}{sub c}{sup +} is observed for the first time. Similar techniques are then used to study {Xi}(1530){sup 0} production in {Lambda}{sub c}{sup +} decay. The spin of the {Xi}(1530) is established for the first time to be 3/2. The existence of an S-wave amplitude in the {Xi}{sup -}{pi}{sup +} system is shown, and its interference with the {Xi}(1530){sup 0} amplitude provides the first clear demonstration of the Breit-Wigner phase motion expected for the {Xi}(1530). The {Xi}{sup -}{pi}{sup +} mass distribution in the vicinity of the {Xi}(1690){sup 0} exhibits interesting structure which may be interpreted as indicating that the {Xi}(1690) has negative parity.

Search for the doubly charmed baryon Ξcc +

NARCIS (Netherlands)

Aaij, R.; Adeva, B.; Adinolfi, M.; Adrover, C.; Affolder, A.; Ajaltouni, Z.; Albrecht, J.; Alessio, F.; Alexander, M.; Ali, S.; Alkhazov, G.; Alvarez Cartelle, P.; Alves, A. A.; Amato, S.; Amerio, S.; Amhis, Y.; Anderlini, L.; Anderson, J.; Andreassen, P.R.; Andrews, J.E.; Appleby, R. B.; Aquines Gutierrez, O.; Archilli, F.; Artamonov, A.; Artuso, M.; Aslanides, E.; Auriemma, G.; Baalouch, M.; Bachmann, S.; Back, J. J.; Badalov, A.; Baesso, C.; Balagura, V.; Baldini, W.; Barlow, R. J.; Barschel, C.; Barsuk, S.; Barter, W.; Bauer, Th.; Bay, A.; Beddow, J.; Bedeschi, F.; Bediaga, I.; Belogurov, S.; Belous, K.; Belyaev, I.; Ben-Haim, E.; Bencivenni, G.; Benson, S.; Benton, J.; Berezhnoy, A.; Bernet, R.; Bettler, M-O.; Van Beuzekom, Martin; Bien, A.; Bifani, S.; Bird, T.D.; Bizzeti, A.; Bjørnstad, P. M.; Blake, T.; Blanc, F.; Blouw, J.; Blusk, S.; Bocci, V.; Bondar, A.; Bondar, N.; Bonivento, W.; Borghi, S.; Borgia, A.; Bowcock, T. J. V.; Bowen, E.; Bozzi, C.; Brambach, T.; Van Den Brand, J.; Bressieux, J.; Brett, D.; Britsch, M.; Britton, T.; Brook, N. H.; Brown, H.; Bursche, A.; Busetto, G.; Buytaert, J.; Cadeddu, S.; Callot, O.; Calvi, M.; Calvo Gomez, M.; Camboni, A.; Campana, P.; Campora Perez, D.; Carbone, A.; Carboni, G.; Cardinale, R.; Cardini, A.; Carranza-Mejia, H.; Carson, L.; Carvalho Akiba, K.; Casse, G.; Castillo Garcia, L.; Cattaneo, M.; Cauet, Ch; Cenci, R.; Charles, M.; Charpentier, Ph; Cheung, S-F.; Chiapolini, N.; Chrzaszcz, M.; Ciba, K.; Cid Vidal, X.; Ciezarek, G.; Clarke, P. E. L.; Clemencic, M.; Cliff, H. V.; Closier, J.; Coca-Pelaz, A.; Coco, V.; Cogan, J.; Cogneras, E.; Collins, P.; Comerma-Montells, A.; Contu, A.; Cook, A.; Coombes, M.; Coquereau, S.; Corti, G.; Couturier, B.; Cowan, G. A.; Craik, D. C.; Cruz Torres, M.; Cunliffe, S.; Currie, C.R.; D'Ambrosio, C.; David, P.; David, P.; Davis, A.; De Bonis, I.; De Bruyn, K.; De Capua, S.; De Cian, M.; de Miranda, J. M.; Paula, L.E.; da-Silva, W.S.; De Simone, P.; Decamp, D.; Deckenhoff, M.; Del Buono, L.; Déléage, N.; Derkach, D.; Deschamps, O.; Dettori, F.; Di Canto, A.; Dijkstra, H.; Dogaru, M.; Donleavy, S.; Dordei, F.; Dosil Suárez, A.; Dossett, D.; Dovbnya, A.; Dupertuis, F.; Durante, P.; Dzhelyadin, R.; Dziurda, A.; Dzyuba, A.; Easo, S.; Egede, U.; Egorychev, V.; Eidelman, S.; Van Eijk, D.; Eisenhardt, S.; Eitschberger, U.; Ekelhof, R.; Eklund, L.; El Rifai, I.; Elsasser, Ch.; Falabella, A.; Färber, C.; Farinelli, C.; Farry, S.; Ferguson, D.; Fernandez Albor, V.; Ferreira Rodrigues, F.; Ferro-Luzzi, M.; Filippov, S.; Fiore, M.; Fitzpatrick, C.; Fontana, Mark; Fontanelli, F.; Forty, R.; De Aguiar Francisco, O.; Frank, M.; Frei, C.; Frosini, M.; Furfaro, E.; Gallas Torreira, A.; Galli, D.; Gandelman, M.; Gandini, P.; Gao, Y.; Garofoli, J.; Garosi, P.; Garra Tico, J.; Garrido, L.; Carvalho-Gaspar, M.; Gauld, Rhorry; Gersabeck, E.; Gersabeck, M.; Gershon, T. J.; Ghez, Ph; Gibson, V.; Giubega, L.; Gligorov, V. V.; Göbel, C.; Golubkov, D.; Golutvin, A.; Gomes, A.Q.; Gorbounov, P.; Head-Gordon, Teresa; Grabalosa Gándara, M.; Graciani Diaz, R.; Granado Cardoso, L. A.; Graugés, E.; Graziani, G.; Grecu, A.; Greening, E.; Gregson, S.; Griffith, P.; Grillo, L.; Grünberg, O.; Gui, B.; Gushchin, E.; Guz, Yu; Gys, T.; Hadjivasiliou, C.; Haefeli, G.; Haen, C.; Haines, S. C.; Hall, S.; Hamilton, B.; Hampson, T.; Hansmann-Menzemer, S.; Harnew, N.; Harnew, S. T.; Harrison, J.; Hartmann, T.; He, J.; Head, T.; Heijne, V.; Hennessy, K.; Henrard, P.; Hernando Morata, J. A.; van Herwijnen, E.; Heß, M.; Hicheur, A.; Hicks, G.E.; Hill, D.; Hoballah, M.; Hombach, C.; Hulsbergen, W.; Hunt, P.; Huse, J.T.; Hussain, N.; Hutchcroft, D. E.; Hynds, D.; Iakovenko, V.; Idzik, M.; Ilten, P.; Jacobsson, R.; Jaeger, A.; Jans, E.; Jaton, P.; Jawahery, A.; Jing, F.; John, M.; Johnson, D.; Jones, C. R.; Joram, C.; Jost, B.; Kaballo, M.; Kandybei, S.; Kanso, W.; Karacson, M.; Karbach, T. M.; Kenyon, I. R.; Ketel, T.; Khanji, B.; Kochebina, O.; Komarov, I.; Koopman, R. F.; Koppenburg, P.; Korolev, M.; Kozlinskiy, A.; Kravchuk, L.; Kreplin, K.; Kreps, M.; Krocker, G.; Krokovny, P.; Kruse, F.; Kucharczyk, M.; Kudryavtsev, V.; Kurek, K.; Kvaratskheliya, T.; La Thi, V. N.; Lacarrere, D.; Lafferty, G. D.; Lai, A.; Lambert, D.M.; Lambert, R. W.; Lanciotti, E.; Lanfranchi, G.; Langenbruch, C.; Latham, T. E.; Lazzeroni, C.; Le Gac, R.; Van Leerdam, J.; Lees, J. P.; Lefèvre, R.; Leflat, A.; Lefrançois, J.; Di Leo, S.; Leroy, O.; Lesiak, T.; Leverington, B.; Li, Y.; Li Gioi, L.; Liles, M.; Lindner, R.; Linn, S.C.; Liu, B.; Liu, G.; Lohn, S.; Longstaff, I.; Lopes, J. H.; Lopez-March, N.; Lu, H.; Lucchesi, D.; Luisier, J.; Luo, H.; Lupton, O.; Machefert, F.; Machikhiliyan, I. V.; Maciuc, F.; Maev, O.; Malde, S.; Manca, G.; Mancinelli, G.; Maratas, J.; Marconi, U.; Marino, P.; Märki, R.; Marks, J.; Martellotti, G.; Martens, A.; Martín Sánchez, A.; Martinelli-Boneschi, F.; Martinez-Santos, D.; Martins Tostes, D.; Martynov, A.; Massafferri, A.; Matev, R.; Mathe, Z.; Matteuzzi, C.; Maurice, E.; Mazurov, A.; McCarthy, J.; Mcnab, A.; McNulty, R.; McSkelly, B.; Meadows, B. T.; Meier, F.; Meissner, M.; Merk, M.; Milanes, D. A.; Minard, M. N.; Molina Rodriguez, J.; Monteil, S.; Moran-Zenteno, D.; Morawski, P.; Mordà, A.; Morello, M. J.; Mountain, R.; Mous, I.; Muheim, F.; Müller, Karl; Muresan, R.; Muryn, B.; Muster, B.; Naik, P.; Nakada, T.; Nandakumar, R.; Nasteva, I.; Needham, M.; Neubert, S.; Neufeld, N.; Nguyen, A. D.; Nguyen, T. D.; Nguyen-Mau, C.; Nicol, M.; Niess, V.; Niet, R.; Nikitin, N.; Nikodem, T.; Nomerotski, A.; Novoselov, A.; Oblakowska-Mucha, A.; Obraztsov, V.; Oggero, S.; Ogilvy, S.; Okhrimenko, O.; Oldeman, R.; Orlandea, M.; Otalora Goicochea, J. M.; Owen, R.P.; Oyanguren, A.; Pal, B. K.; Palano, A.; Palutan, M.; Panman, J.; Papanestis, A.; Pappagallo, M.; Parkes, C.; Parkinson, C. J.; Passaleva, G.; Patel, G. D.; Patel, M.; Patrick, G. N.; Patrignani, C.; Pavel-Nicorescu, C.; Pazos Alvarez, A.; Pearce, D.A.; Pellegrino, A.; Penso, G.; Pepe Altarelli, M.; Perazzini, S.; Perez Trigo, E.; Pérez-Calero Yzquierdo, A.; Perret, P.; Perrin-Terrin, M.; Pescatore, L.; Pesen, E.; Pessina, G.; Petridis, K.; Petrolini, A.; Phan, A.; Picatoste Olloqui, E.; Pietrzyk, B.; Pilař, T.; Pinci, D.; Playfer, S.; Plo Casasus, M.; Polci, F.; Polok, G.; Poluektov, A.; Polycarpo, E.; Popov, A.; Popov, D.; Popovici, B.; Potterat, C.; Powell, A.; Prisciandaro, J.; Pritchard, C.A.; Prouve, C.; Pugatch, V.; Puig Navarro, A.; Punzi, G.; Qian, Y.W.; Rachwal, B.; Rademacker, J. H.; Rakotomiaramanana, B.; Rangel, M. S.; Raniuk, I.; Rauschmayr, N.; Raven, G.; Redford, S.; Reichert, S.; Reid, M.; dos Reis, A. C.; Ricciardi, S.; Richards, Al.; Rinnert, K.; Rives Molina, V.; Roa Romero, D. A.; Robbe, P.; Roberts, D. A.; Rodrigues, A. B.; Rodrigues, L.E.T.; Rodriguez Perez, P.; Roiser, S.; Romanovsky, V.; Romero Vidal, A.; Rotondo, M.; Rouvinet, J.; Ruf, T.; Ruffini, F.; Ruiz, van Hapere; Ruiz Valls, P.; Sabatino, G.; Saborido Silva, J. J.; Sagidova, N.; Sail, P.; Saitta, B.; Salustino Guimaraes, V.; Sanmartin Sedes, B.; Santacesaria, R.; Santamarina Rios, C.; Santovetti, E.; Sapunov, M.; Sarti, A.; Satriano, C.; Satta, A.; Savrie, M.; Savrina, D.; Schiller, M.; Schindler, R. H.; Schlupp, M.; 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.; Shapkin, M.; Shapoval, I.; Shcheglov, Y.; Shears, T.; Shekhtman, L.; Shevchenko, O.; Shevchenko, V.; Shires, A.; Silva Coutinho, R.; Sirendi, M.; Skidmore, N.; Skwarnicki, T.; Smith, N. A.; Smith, E.; Smith, E.; Smith, J; Smith, M.; Sokoloff, M. D.; Soler, F. J. P.; Soomro, F.; de Souza, D.K.; Souza De Paula, B.; Spaan, B.; Sparkes, A.; Spradlin, P.; Stagni, F.; Stahl, S.; Steinkamp, O.; Stevenson-Moore, P.; Stoica, S.; Stone, S.; Storaci, B.; Straticiuc, M.; Straumann, U.; Subbiah, V. K.; Sun, L.; Sutcliffe, W.; Swientek, S.; Syropoulos, V.; Szczekowski, M.; Szczypka, P.; Szilard, D.; Szumlak, T.; T'Jampens, S.; Teklishyn, M.; Teodorescu, E.; Teubert, F.; Thomas, C.; Thomas, E.; Van Tilburg, J.; Tisserand, V.; Tobin, M. N.; Tolk, S.; Tonelli, D.; Topp-Joergensen, S.; Torr, N.; Tournefier, E.; Tourneur, S.; Tran, N.T.M.T.; Tresch, M.; Tsaregorodtsev, A.; Tsopelas, P.; Tuning, N.; Ubeda Garcia, M.; Ukleja, A.; Ustyuzhanin, A.; Uwer, U.; Vagnoni, V.; Valenti, G.; Vallier, A.; Vazquez Gomez, R.; Vazquez Regueiro, P.; Vázquez Sierra, C.; Vecchi, S.; Velthuis, M.J.; Veltri, M.; Veneziano, G.; Vesterinen, M.; Viaud, B.; Vieira, D.; Vilasis-Cardona, X.; Vollhardt, A.; Volyanskyy, D.; Voong, D.; Vorobyev, A.; Vorobyev, V.; Voß, C.; Voss, H.; Waldi, R.; Wallace, C.; Wallace, R.; Wandernoth, S.; Wang, J.; Ward, D. R.; Watson, N. K.; Webber, A. D.; Websdale, D.; Whitehead, M.; Wicht, J.; Wiechczynski, J.; Wiedner, D.; Wiggers, L.; Wilkinson, G.; Williams, M.P.; Williams, M.; Wilson, James F; Wimberley, J.; Wishahi, J.; Wislicki, W.; Witek, M.; Wormser, G.; Wotton, S. A.; Wright, S.J.; Wu, S.; Wyllie, K.; Xie, Y.; Xing, Z.; Yang, Z.; Yuan, X.; Yushchenko, O.; Zangoli, M.; Zavertyaev, M.; Zhang, F.; Zhang, L.; Zhang, W. C.; Zhang, Y.; Zhelezov, A.; Zhokhov, A.; Zhong, L.; Zvyagin, A.

2013-01-01

A search for the doubly charmed baryon Ξcc + in the decay mode Ξcc + → Λc +K-π+ is performed with a data sample, corresponding to an integrated luminosity of 0.65 fb-1, of pp collisions recorded at a centre-of-mass energy of 7TeV. No significant signal is found in the mass range 3300-3800 MeV/c2.

Baryon Resonances

International Nuclear Information System (INIS)

Oset, E.; Sarkar, S.; Sun Baoxi; Vicente Vacas, M.J.; Ramos, A.; Gonzalez, P.; Vijande, J.; Martinez Torres, A.; Khemchandani, K.

2010-01-01

In this talk I show recent results on how many excited baryon resonances appear as systems of one meson and one baryon, or two mesons and one baryon, with the mesons being either pseudoscalar or vectors. Connection with experiment is made including a discussion on old predictions and recent results for the photoproduction of the Λ(1405) resonance, as well as the prediction of one 1/2 + baryon state around 1920 MeV which might have been seen in the γp→K + Λ reaction.

Polarization effects in the reaction of charm baryon production on colliding electron-positron beams

International Nuclear Information System (INIS)

Rekalo, M.P.; Korzh, A.P.; Barannik, V.P.

1980-01-01

To calculate energy and angular distributions of various decay products of charm baAyons, which are prodUced in reactions on colliding e + e - beams, it is necessary to know the differential cross sections of the e + e - → C+anti C process which correspond to different polarized states of produced C and anti C (C - charm baryon). These differential cross sections are calculated for a single-photon mechanism with respect to the contribution of the anapole and electric dipole form factors of C-baryon. Polarizations of colliding electron-positron beams are taken into account in a full volume

Bag-model matrix elements of the parity-violating weak hamiltonian for charmed baryons

International Nuclear Information System (INIS)

Ebert, D.; Kallies, W.

1983-01-01

Baryon matrix elements of the parity-violating part of the charmchanging weak Hamiltonian might be significant and comparable with those of the parity-conserving one due to large symmetry breaking. Expression for these new matrix elements by using the MIT-bag model are derived and their implications on earlier calculations of nonleptonic charmed-baryon decays are estimated

Three-body charmful baryonic B decays B-bar→D(D*)NN-bar

International Nuclear Information System (INIS)

Cheng Haiyang; Yang Kweichou

2002-01-01

We study the charmful three-body baryonic B decays B-bar→D ( * ) NN-bar: the color-allowed modes B-bar 0 →D ( * )+ np-bar and the color-suppressed ones B-bar 0 →D ( * )0 pp-bar. While the D* + /D + production ratio is predicted to be of order 3, it is found that D 0 pp-bar has a similar rate as D* 0 pp-bar. It is pointed out that B-bar 0 →D(D*)NN-bar are dominated by the nucleon vector current or by vector meson intermediate states, whereas B-bar 0 →D 0 pp-bar proceeds mainly via the exchange of the axial-vector intermediate state a 1 (1260). The study of the NN-bar invariant mass distribution in general indicates a threshold baryon pair production; that is, a recoil charmed meson accompanied by a low mass baryon pair except that the spectrum of D 0 pp-bar has a hump at large pp-bar invariant mass m pp-bar ∼3.0 GeV

Charm and Hidden Charm Scalar Resonances in Nuclear Matter

NARCIS (Netherlands)

Tolos, Laura; Molina, Raquel; Gamermann, Daniel; Oset, Eulogio

2009-01-01

We study the properties of the scalar charm resonances D(s0)(2317) and D(0)(2400), and the theoretical hidden charm state X(3700) in nuclear matter. We find that for the D(s0)(2317) and X(3700) resonances, with negligible and small width at zero density, respectively, the width becomes about 100 MeV

On the search for the electric dipole moment of strange and charm baryons at LHC

Energy Technology Data Exchange (ETDEWEB)

Botella, F.J.; Garcia Martin, L.M.; Martinez Vidal, F.; Oyanguren, A.; Ruiz Vidal, J. [Universitat de Valencia-CSIC, Instituto de Fisica Corpuscular (IFIC), Valencia (Spain); Marangotto, D.; Merli, A.; Neri, N. [INFN Sezione di Milano, Milan (Italy); Milano Univ., Milan (Italy)

2017-03-15

Permanent electric dipole moments (EDMs) of fundamental particles provide powerful probes for physics beyond the Standard Model. We propose to search for the EDM of strange and charm baryons at LHC, extending the ongoing experimental program on the neutron, muon, atoms, molecules and light nuclei. The EDM of strange Λ baryons, selected from weak decays of charm baryons produced in pp collisions at LHC, can be determined by studying the spin precession in the magnetic field of the detector tracking system. A test of CPT symmetry can be performed by measuring the magnetic dipole moment of Λ and anti Λ baryons. For short-lived Λ{sup +}{sub c} and Ξ{sup +}{sub c} baryons, to be produced in a fixed-target experiment using the 7 TeV LHC beam and channeled in a bent crystal, the spin precession is induced by the intense electromagnetic field between crystal atomic planes. The experimental layout based on the LHCb detector and the expected sensitivities in the coming years are discussed. (orig.)

Baryons and baryon resonances in nuclear matter

Science.gov (United States)

Lenske, Horst; Dhar, Madhumita; Gaitanos, Theodoros; Cao, Xu

2018-01-01

Theoretical approaches to the production of hyperons and baryon resonances in elementary hadronic reactions and heavy ion collisions are reviewed. The focus is on the production and interactions of baryons in the lowest SU(3) flavor octet and states from the next higher SU(3) flavor decuplet. Approaches using the SU(3) formalism for interactions of mesons and baryons and effective field theory for hyperons are discussed. An overview of application to free space and in-medium baryon-baryon interactions is given and the relation to a density functional theory is indicated. The intimate connection between baryon resonances and strangeness production is shown first for reactions on the nucleon. Pion-induced hypernuclear reactions are shown to proceed essentially through the excitation of intermediate nucleon resonances. Transport theory in conjunction with a statistical fragmentation model is an appropriate description of hypernuclear production in antiproton and heavy ion induced fragmentation reactions. The excitation of subnuclear degrees of freedom in peripheral heavy ion collisions at relativistic energies is reviewed. The status of in-medium resonance physics is discussed.

e+e--annihilation into baryon-antibaryon pairs

International Nuclear Information System (INIS)

Koerner, J.G.; Kuroda, M.

1976-07-01

Using GVDM-type form factors we calculate the e + -e - production cross sections for the reactions e + e - → 1 + /2 - anti(1 +- /2), 1 + /2 - anti(3 +- /2), 1 + /2 - anti(5 + /2) and 3 + /2 - anti(3 + /2) including all prominent baryon resonances at energies of present and planned e + -e - storage ring machines. We also evaluate the cross section of charmed baryon pair production. Near their respective thresholds charmed and uncharmed baryon pair production are predicted to constitute comparable fractions of the total hadronic cross section. The calculated cross sections indicate that the interference of direct and 1-photon decay of the PSI-particles into baryon pairs is small. (orig.) [de

Flavor structure of Λ baryons from lattice QCD: From strange to charm quarks

Science.gov (United States)

Gubler, Philipp; Takahashi, Toru T.; Oka, Makoto

2016-12-01

We study Λ baryons of spin-parity 1/2± with either a strange or charm valence quark in full 2 +1 flavor lattice QCD. Multiple S U (3 ) singlet and octet operators are employed to generate the desired single baryon states on the lattice. Via the variational method, the couplings of these states to the different operators provide information about the flavor structure of the Λ baryons. We make use of the gauge configurations of the PACS-CS Collaboration and chirally extrapolate the results for the masses and S U (3 ) flavor components to the physical point. We furthermore gradually change the hopping parameter of the heaviest quark from strange to charm to study how the properties of the Λ baryons evolve as a function of the heavy quark mass. It is found that the baryon energy levels increase almost linearly with the quark mass. Meanwhile, the flavor structure of most of the states remains stable, with the exception of the lowest 1/2- state, which changes from a flavor singlet Λ to a Λc state with singlet and octet components of comparable size. Finally, we discuss whether our findings can be interpreted with the help of a simple quark model and find that the negative-parity Λc states can be naturally explained as diquark excitations of the light u and d quarks. On the other hand, the quark-model picture does not appear to be adequate for the negative-parity Λ states, suggesting the importance of other degrees of freedom to describe them.

Quark-diquark model description for double charm baryons

International Nuclear Information System (INIS)

Majethiya, A.; Patel, B.; Vinodkumar, P. C.

2010-01-01

We report here the mass spectrum and magnetic moments of ccq(q (implied by) u, d, s) systems in the potential model framework by assuming the inter-quark potential as the colour coulomb plus power form with power index ν varying between 0.1 to 2.0. Here the two charm quarks are considered for the diquark states. The conventional one gluon exchange interaction has been employed to get the hyperfine and the fine structure between different states. We have predicted many low-lying states whose experimental verification can exclusively support the quark-diquark structure of the baryons. (authors)

Charmed hadrons in nuclear medium

NARCIS (Netherlands)

Tolos, L.; Gamermann, D.; Garcia-Recio, C.; Molina, R.; Nieves, J.; Oset, E.; Ramos, A.

We study the properties of charmed hadrons in dense matter within a coupled-channel approach which accounts for Pauli blocking effects and meson self-energies in a self-consistent manner We analyze the behaviour in this dense environment of dynamically-generated baryonic resonances as well as the

Observation of an Excited Charm Baryon OmegaC* Decaying to OmegaC0 Gamma

OpenAIRE

The BABAR Collaboration; Aubert, B.

2006-01-01

We report the first observation of an excited singly-charm baryon OmegaC* (css) in the radiative decay OmegaC0 Gamma, where the OmegaC0 baryon is reconstructed in the decays to the final states Omega-pi+, Omega-pi+pi0, Omega-pi+pi-pi+, and Cascade-K-pi+pi+. This analysis is performed using a dataset of 230.7 fb$-1} collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The mass difference between the OmegaC* and the OmegaC0 baryons...

Photoproduction asymmetries of the charm baryons Λc, Σc++ and Σc0 at the Fermilab experiment E831/focus

International Nuclear Information System (INIS)

Anjos, Joao dos; Estrada, Cecilia Uribe; Sheaff, Marleigh

2000-01-01

Full text follows: In photon-hadron collisions, it is expected that charm quarks are produced by the photon-gluon process. This process at leading order (LO) in perturbative quantum chromo-dynamics (QCD) predicts symmetric distributions for charm/anticharm quark production. Asymmetries introduced by next to leading order (NLO) calculations are expected to be negligibly small. However, when the charm/articharm quarks hadronize, non perturbative effects in the recombination process may induce an asymmetry between charm and anticharm final states. The measurement of photoproduction asymmetries could provide valuable information on the hadronization process, which is one of the least understood phenomena in QCD. We present a study on the charm-anticharm photoproduction asymmetry using Λ c + /Λ c - , Σ c ++ /Σ c -- and Σ c 0 /Σ-bar c 0 baryon candidates. Data used is from the E831/FOCUS experiment, collected during 1996-1997 Fermilab fixed target run. The asymmetry is studied in intervals of p T 2 , p L , and x F for the case of Λ c baryons, while global values are extracted for the Σ c baryons, due to the lack of statistics. (author)

Observation of the Doubly Charmed Baryon Ξ_{cc}^{++}.

Science.gov (United States)

Aaij, R; Adeva, B; Adinolfi, M; Ajaltouni, Z; Akar, S; Albrecht, J; Alessio, F; Alexander, M; Alfonso Albero, A; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amerio, S; Amhis, Y; An, L; Anderlini, L; Andreassi, G; Andreotti, M; Andrews, J E; Appleby, R B; Archilli, F; d'Argent, P; Arnau Romeu, J; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Baalouch, M; Babuschkin, I; Bachmann, S; Back, J J; Badalov, A; Baesso, C; Baker, S; Balagura, V; Baldini, W; Baranov, A; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Baryshnikov, F; Batozskaya, V; Battista, V; Bay, A; Beaucourt, L; Beddow, J; Bedeschi, F; Bediaga, I; Beiter, A; Bel, L J; Beliy, N; Bellee, V; Belloli, N; Belous, K; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Beranek, S; Berezhnoy, A; Bernet, R; Berninghoff, D; Bertholet, E; Bertolin, A; Betancourt, C; Betti, F; Bettler, M-O; van Beuzekom, M; Bezshyiko, Ia; Bifani, S; Billoir, P; Birnkraut, A; Bitadze, A; Bizzeti, A; Bjoern, M B; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Boettcher, T; Bondar, A; Bondar, N; Bonivento, W; Bordyuzhin, I; Borgheresi, A; Borghi, S; Borisyak, M; Borsato, M; Borysova, M; Bossu, F; Boubdir, M; Bowcock, T J V; Bowen, E; Bozzi, C; Braun, S; Britton, T; Brodzicka, J; Brundu, D; Buchanan, E; Burr, C; Bursche, A; Buytaert, J; Byczynski, W; Cadeddu, S; Cai, H; Calabrese, R; Calladine, R; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Campora Perez, D H; Capriotti, L; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carniti, P; Carson, L; Carvalho Akiba, K; Casse, G; Cassina, L; Castillo Garcia, L; Cattaneo, M; Cavallero, G; Cenci, R; Chamont, D; Charles, M; Charpentier, Ph; Chatzikonstantinidis, G; Chefdeville, M; Chen, S; Cheung, S F; Chitic, S-G; Chobanova, V; Chrzaszcz, M; Chubykin, A; Ciambrone, P; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Cogan, J; Cogneras, E; Cogoni, V; Cojocariu, L; Collins, P; Colombo, T; Comerma-Montells, A; Contu, A; Cook, A; Coombs, G; Coquereau, S; Corti, G; Corvo, M; Costa Sobral, C M; Couturier, B; Cowan, G A; Craik, D C; Crocombe, A; Cruz Torres, M; Currie, R; D'Ambrosio, C; Da Cunha Marinho, F; Dall'Occo, E; Dalseno, J; Davis, A; De Aguiar Francisco, O; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Serio, M; De Simone, P; Dean, C T; Decamp, D; Del Buono, L; Dembinski, H-P; Demmer, M; Dendek, A; Derkach, D; Deschamps, O; Dettori, F; Dey, B; Di Canto, A; Di Nezza, P; Dijkstra, H; Dordei, F; Dorigo, M; Dosil Suárez, A; Douglas, L; Dovbnya, A; Dreimanis, K; Dufour, L; Dujany, G; Durante, P; Dzhelyadin, R; Dziewiecki, M; Dziurda, A; Dzyuba, A; Easo, S; Ebert, M; Egede, U; Egorychev, V; Eidelman, S; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; Ely, S; Esen, S; Evans, H M; Evans, T; Falabella, A; Farley, N; Farry, S; Fay, R; Fazzini, D; Federici, L; Ferguson, D; Fernandez, G; Fernandez Declara, P; Fernandez Prieto, A; Ferrari, F; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fini, R A; Fiore, M; Fiorini, M; Firlej, M; Fitzpatrick, C; Fiutowski, T; Fleuret, F; Fohl, K; Fontana, M; Fontanelli, F; Forshaw, D C; Forty, R; Franco Lima, V; Frank, M; Frei, C; Fu, J; Funk, W; Furfaro, E; Färber, C; Gabriel, E; Gallas Torreira, A; Galli, D; Gallorini, S; Gambetta, S; Gandelman, M; Gandini, P; Gao, Y; Garcia Martin, L M; García Pardiñas, J; Garra Tico, J; Garrido, L; Garsed, P J; Gascon, D; Gaspar, C; Gavardi, L; Gazzoni, G; Gerick, D; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gianì, S; Gibson, V; Girard, O G; Giubega, L; Gizdov, K; Gligorov, V V; Golubkov, D; Golutvin, A; Gomes, A; Gorelov, I V; Gotti, C; Govorkova, E; Grabowski, J P; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graverini, E; Graziani, G; Grecu, A; Greim, R; Griffith, P; Grillo, L; Gruber, L; Gruberg Cazon, B R; Grünberg, O; Gushchin, E; Guz, Yu; Gys, T; Göbel, C; Hadavizadeh, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hamilton, B; Han, X; Hancock, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Hasse, C; Hatch, M; He, J; Hecker, M; Heinicke, K; Heister, A; Hennessy, K; Henrard, P; Henry, L; van Herwijnen, E; Heß, M; Hicheur, A; Hill, D; Hombach, C; Hopchev, P H; Huard, Z-C; Hulsbergen, W; Humair, T; Hushchyn, M; Hutchcroft, D; Ibis, P; Idzik, M; Ilten, P; Jacobsson, R; Jalocha, J; Jans, E; Jawahery, A; Jiang, F; John, M; Johnson, D; Jones, C R; Joram, C; Jost, B; Jurik, N; Kandybei, S; Karacson, M; Kariuki, J M; Karodia, S; Kazeev, N; Kecke, M; Kelsey, M; Kenzie, M; Ketel, T; Khairullin, E; Khanji, B; Khurewathanakul, C; Kirn, T; Klaver, S; Klimaszewski, K; Klimkovich, T; Koliiev, S; Kolpin, M; Komarov, I; Kopecna, R; Koppenburg, P; Kosmyntseva, A; Kotriakhova, S; Kozeiha, M; Kreps, M; Krokovny, P; Kruse, F; Krzemien, W; Kucewicz, W; Kucharczyk, M; Kudryavtsev, V; Kuonen, A K; Kurek, K; Kvaratskheliya, T; Lacarrere, D; Lafferty, G; Lai, A; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Leflat, A; Lefrançois, J; Lefèvre, R; Lemaitre, F; Lemos Cid, E; Leroy, O; Lesiak, T; Leverington, B; Li, P-R; Li, T; Li, Y; Li, Z; Likhomanenko, T; Lindner, R; Lionetto, F; Lisovskyi, V; Liu, X; Loh, D; Loi, A; Longstaff, I; Lopes, J H; Lucchesi, D; Lucio Martinez, M; Luo, H; Lupato, A; Luppi, E; Lupton, O; Lusiani, A; Lyu, X; Machefert, F; Maciuc, F; Macko, V; Mackowiak, P; Maddock, B; Maddrell-Mander, S; Maev, O; Maguire, K; Maisuzenko, D; Majewski, M W; Malde, S; Malinin, A; Maltsev, T; Manca, G; Mancinelli, G; Manning, P; Marangotto, D; Maratas, J; Marchand, J F; Marconi, U; Marin Benito, C; Marinangeli, M; Marino, P; Marks, J; Martellotti, G; Martin, M; Martinelli, M; Martinez Santos, D; Martinez Vidal, F; Martins Tostes, D; Massacrier, L M; Massafferri, A; Matev, R; Mathad, A; Mathe, Z; Matteuzzi, C; Mauri, A; Maurice, E; Maurin, B; Mazurov, A; McCann, M; McNab, A; McNulty, R; Mead, J V; Meadows, B; Meaux, C; Meier, F; Meinert, N; Melnychuk, D; Merk, M; Merli, A; Michielin, E; Milanes, D A; Millard, E; Minard, M-N; Minzoni, L; Mitzel, D S; 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2017-09-15

A highly significant structure is observed in the Λ_{c}^{+}K^{-}π^{+}π^{+} mass spectrum, where the Λ_{c}^{+} baryon is reconstructed in the decay mode pK^{-}π^{+}. The structure is consistent with originating from a weakly decaying particle, identified as the doubly charmed baryon Ξ_{cc}^{++}. The difference between the masses of the Ξ_{cc}^{++} and Λ_{c}^{+} states is measured to be 1334.94±0.72(stat.)±0.27(syst.)  MeV/c^{2}, and the Ξ_{cc}^{++} mass is then determined to be 3621.40±0.72(stat.)±0.27(syst.)±0.14(Λ_{c}^{+})  MeV/c^{2}, where the last uncertainty is due to the limited knowledge of the Λ_{c}^{+} mass. The state is observed in a sample of proton-proton collision data collected by the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.7  fb^{-1}, and confirmed in an additional sample of data collected at 8 TeV.

Discovery of the doubly charmed baryon $\\Xi_{cc}^{++}$ at LHCb

CERN Document Server

Spradlin, Patrick

2017-01-01

The LHCb collaboration announced the first observation of the doubly charmed baryon $\\Xi_{cc}^{++}$, which was discovered decaying to a $\\Lambda_{c}^{+}K^{-}\\pi^{+}\\pi^{+}$ final state. A highly significant structure is found in the $\\Lambda_{c}^{+}K^{-}\\pi^{+}\\pi^{+}$ mass spectrum in proton-proton collision data collected by the LHCb experiment at center-of-mass energies of 13 TeV and 8 TeV. The peak contains $313 \\pm 33$ decays in the 13 TeV sample and $113 \\pm 21$ decays in the 8 TeV, with local significances in excess of $12\\sigma$ and $7\\sigma$ respectively. The narrow structure has a width that is consistent with experimental resolution, and its properties are consistent with those of a weakly decaying state and inconsistent with those of a strongly decaying state. The difference between the masses of the structure, identified as $\\Xi_{cc}^{++}$, and the $\\Lambda_{c}^{+}$ baryon is $1334.94 \\pm 0.72(\\mbox{stat.}) \\pm 0.27(\\mbox{syst.})\\,\\mbox{MeV}/c^{2}$, and the mass of the $\\Xi_{cc}^{++}$ baryon ...

Doubly charmed baryon production in heavy ion collisions

Science.gov (United States)

Yao, Xiaojun; Müller, Berndt

2018-04-01

We give an estimate of Ξcc ++ production rate and transverse momentum spectra in relativistic heavy ion collisions. We use Boltzmann transport equations to describe the dynamical evolution of charm quarks and diquarks inside quark-gluon plasma. In-medium formation and dissociation rates of charm diquarks are calculated from potential nonrelativistic QCD for the diquark sector. We solve the transport equations by Monte Carlo simulations. For 2.76 TeV Pb-Pb collisions with 0-10% centrality, the number of Ξcc ++ produced in the transverse momentum range 0-5 GeV and rapidity from -1 to 1 is roughly 0.02 per collision. We repeat the calculation with a melting temperature 250 MeV above which no diquarks can be formed. The number of Ξcc ++ produced in the same kinematic region is about 0.0125 per collision. We discuss how to study diquarks at finite temperature on a lattice and construct the antitriplet free energy in a gauge invariant but path dependent way. We also comment on extensions of the calculation to other doubly heavy baryons and doubly heavy tetraquarks and the feasibility of experimental measurements.

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

Excited-state spectroscopy of singly, doubly and triply-charmed baryons from lattice QCD

Energy Technology Data Exchange (ETDEWEB)

Padmanath, M. [Tata Institute; Edwards, Robert G. [JLAB; Mathur, Nilmani [Tata Institute; Peardon, Michael [Trinity College

2014-07-01

We present the ground and excited state spectra of singly, doubly and triply-charmed baryons by using dynamical lattice QCD. A large set of baryonic operators that respect the symmetries of the lattice and are obtained after subduction from their continuum analogues are utilized. These operators transform as irreducible representations of SU(3)F symmetry for flavour, SU(4) symmetry for Dirac spins of quarks and O(3) symmetry for orbital angular momenta. Using novel computational techniques correlation functions of these operators are generated and the variational method is exploited to extract excited states. The lattice spectra that we obtain have baryonic states with well-defined total spins up to 7/2 and the low lying states remarkably resemble the expectations of quantum numbers from SU(6)ⓍO(3) symmetry.

Charmed baryon production in e/sup +/e/sup -/ annihilation in the upsilon region

International Nuclear Information System (INIS)

Mestayer, M.D.

1985-01-01

The author has observed the production of Λ/sub c/ baryons in e/sup +/e/sup -/ annihilation by reconstructing their mass from the decay mode Λ/sub c/ → Λπ/sup +/π/sup +/π/sup -/. They compare the production rates of the Λ/sub c/ with that of the D/sup +/ meson, which they detect through its K-bar 0 π/sup +/π/sup +/π/sup -/ decay mode. The similarity of the kinematics of the two decays implies that much of the systematic uncertainty in detection efficiency cancels in the ratio of the rates, thereby allowing a comparison of charmed baryon and meson hardonization

Lecture II. Charmed particle spectroscopy

International Nuclear Information System (INIS)

Anon.

1978-01-01

The discussion of charmed particle spectroscopy covers the particle properties and interrelations from a charmed quark composition point of view including SU(4)-symmetry generalities, mesons, baryons, charmed particle masses, and decays of charmed particles. 6 references

Search for the doubly charmed baryon $\\Xi_{cc}^+$

CERN Document Server

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Williams, M P; Williams, M; Wilson, F F; Wimberley, J; Wishahi, J; Wislicki, W; Witek, M; Wormser, G; Wotton, S A; Wright, S; Wu, S; Wyllie, K; Xie, Y; Xing, Z; Yang, Z; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhokhov, A; Zhong, L; Zvyagin, A

2013-01-01

A search for the doubly charmed baryon $\\Xi_{cc}^{+}$ in the decay mode $\\Xi_{cc}^{+} \\to \\Lambda_c^+ K^- \\pi^+$ is performed with a data sample, corresponding to an integrated luminosity of 0.65 fb$^{-1}$, of $pp$ collisions recorded at a centre-of-mass energy of 7 TeV. No significant signal is found in the mass range 3300--3800 MeV$/c^2$. Upper limits at the 95\\% confidence level on the ratio of the $\\Xi_{cc}^{+}$ production cross-section times branching fraction to that of the $\\Lambda_c^+$, $R$, are given as a function of the $\\Xi_{cc}^{+}$ mass and lifetime. The largest upper limits range from $R<1.5 \\times 10^{-2}$ for a lifetime of 100 fs to $R<3.9 \\times 10^{-4}$ for a lifetime of 400 fs.

The melting and abundance of open charm hadrons

Directory of Open Access Journals (Sweden)

A. Bazavov

2014-10-01

Full Text Available Ratios of cumulants of conserved net charge fluctuations are sensitive to the degrees of freedom that are carriers of the corresponding quantum numbers in different phases of strong interaction matter. Using lattice QCD with 2+1 dynamical flavors and quenched charm quarks we calculate second and fourth order cumulants of net charm fluctuations and their correlations with other conserved charges such as net baryon number, electric charge and strangeness. Analyzing appropriate ratios of these cumulants we probe the nature of charmed degrees of freedom in the vicinity of the QCD chiral crossover region. We show that for temperatures above the chiral crossover transition temperature, charmed degrees of freedom can no longer be described by an uncorrelated gas of hadrons. This suggests that the dissociation of open charm hadrons and the emergence of deconfined charm states sets in just near the chiral crossover transition. Till the crossover region we compare these lattice QCD results with two hadron resonance gas models—including only the experimentally established charmed resonances and also including additional states predicted by quark model and lattice QCD calculations. This comparison provides evidence for so far unobserved charmed hadrons that contribute to the thermodynamics in the crossover region.

Observation of an Excited Charm Baryon Omega*C Decaying to OmegaC0 Gamma

International Nuclear Information System (INIS)

Aubert, B

2006-01-01

The authors report the first observation of an excited singly-charmed baryon (Omega)* c (css) in the radiative decay (Omega) c 0 γ, where the (Omega) c 0 baryon is reconstructed in the decays to the final states (Omega) - π + , (Omega) - π + π 0 , (Omega) - π + π - π + , and Ξ - K - π + π + . This analysis is performed using a dataset of 230.7 fb -1 collected by the BABAR detector at the PEP-II asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The mass difference between the (Omega)* c and the (Omega) c 0 baryons is measured to be 70.8 ± 1.0(stat) ± 1.1(syst) MeV/c 2 . They also measure the ratio of inclusive production cross sections of (Omega)* c and (Omega) c 0 in e + e - annihilation

Effects of pseudoscalar-baryon channels in the dynamically generated vector-baryon resonances

Energy Technology Data Exchange (ETDEWEB)

Garzon, E.J.; Oset, E. [Centro Mixto Universidad de Valencia-CSIC, Institutos de Investigacion de Paterna, Departamento de Fisica Teorica and IFIC, Valencia (Spain)

2012-01-15

We study the interaction of vector mesons with the octet of stable baryons in the framework of the local hidden gauge formalism using a coupled-channels unitary approach, including also the pseudoscalar-baryon channels which couple to the same quantum numbers. We examine the scattering amplitudes and their poles, which can be associated to the known J{sup P}=1/2{sup -}, 3/2{sup -} baryon resonances, and determine the role of the pseudoscalar-baryon channels, changing the width and eventually the mass of the resonances generated with only the basis of vector-baryon states. (orig.)

Measurement of the {Lambda}{sub c} charmed baryon production and the study of the {Lambda}{sub c} baryon semi-leptonic decays by the DELPHI experiment at LEP; Mesure de la production du baryon charme {Lambda}{sub c} et etude des desintegrations semi-leptoniques de baryon {Lambda}{sub c} par l`experience DELPHI au LEP

Energy Technology Data Exchange (ETDEWEB)

Bertini, D [Lyon-1 Univ., 69 (France)

1997-04-24

By using the data accumulated in the DELPHI experiment from 1992 to 1994 we present the results of the production rate measurement of {Lambda}{sub c} charmed baryons generated in the bb-bar and cc-bar events. For these measurements we reconstructed entirely the {Lambda}{sub c} baryons decaying in pK{pi}. Then we select a set of bottom baryons {Lambda}{sub b}{sup 0} by means of its semi-leptonic decays in {Lambda}{sub c}{sup +}l{sup -}{nu}{sub l}-bar. The study of distribution of these events as a function of the transfer momentum allowed estimating for the first time the slope of the {Lambda}{sub b}{sup 0} form factor. (author) 93 refs.

First Observation of An Excited Charm Baryon Decaying to Omega Charm Baryon at the BaBar Experiment

International Nuclear Information System (INIS)

Bula, Rahmi; SUNY, Albany

2007-01-01

We have carried out a search for a charmed baryon (Omega) * c decaying to (Omega) 0 c and a γ where (Omega) c candidates are reconstructed using decay modes (Omega) - π + (c1), (Omega) - π + π 0 (c2), (Omega) - π + π - π + (c3) and Ξ - K - π + π + (c4). This search is performed by analyzing integrated luminosity of 230.7 fb -1 data collected by the BABAR detector at the Stanford Linear Accelerator Center. In decay channel (Omega) * c → (Omega) 0 c ((Omega) - π + )γ (C1), we observe a signal yield of 39.2 +9.8 -9.1 (stat)±6.0(syst) events with a significance of 4.2 standard deviations. In decay channels (Omega) * c → (Omega) 0 c ((Omega) - π + π 0 )γ (C2) and (Omega) * c → (Omega) 0 c (Ξ - K - π + π + )γ (C4), we observe signal yields of 55.2 16.1 -15.2 ± 5.6 and 20.2 +9.3 -8.5 ± 3.1 with significances of 3.4 and 2.0 σ, respectively. As for the (Omega) * c → (Omega) 0 c ((Omega) - π + π - π + )γ (C3) decay channel, we observe signal yields of -5.1 +5.3.8 -4.7 ±1.0 without a positive significance. We assume the same production mechanism for the four decay channels of (Omega) * c studied. By combining these four channels, the fit results in a signal yield of 105.3 +21.2 -20.5 ± 6.0 events with a significance of 5.2 σ. We report the mass difference (Omega) * c - (Omega) 0 c ((delta)m) of the singly charmed baryon (Omega) * c to be 70.8 +1.0 -1.0 ± 1.1 MeV. Finally, the ratios of production cross sections are calculated: σ(e + e - →C1)/σ(e + e - →c1) = 0.71 +0.19 -0.18 ±0.11, σ(e + e - →C2)/σ(e + e - →c2) = 1.76 +0.71 -0.69 ±0.19, σ(e + e - →C3)/σ(e + e - →c3) = -0.66 +0.74 -0.66 ±0.13, σ(e + e - →C4)/σ(e + e - →c4) = 1.70 +1.0 -1.0 ±0.27 and σ(e + e - →(Omega) * c (combined))/σ(e + e - →(Omega) 0 c ) = 1.0 +0.23 -0.22 ±0.11

Masses and sigma terms of doubly charmed baryons up to O (p4) in manifestly Lorentz-invariant baryon chiral perturbation theory

Science.gov (United States)

Yao, De-Liang

2018-02-01

We calculate the masses and sigma terms of the doubly charmed baryons up to next-to-next-to-next-to-leading order [i.e., O (p4) ] in a covariant baryon chiral perturbation theory by using the extended-on-mass-shell renormalization scheme. Their expressions both in infinite and finite volumes are provided for chiral extrapolation in lattice QCD. As a first application, our chiral results of the masses are confronted with the existing lattice QCD data in the presence of finite-volume corrections. Up to O (p3) , all relevant low-energy constants can be well determined. As a consequence, we obtain the physical values for the masses of Ξc c and Ωc c baryons by extrapolating to the physical limit. Our determination of the Ξc c mass is consistent with the recent experimental value by LHCb Collaboration, however, larger than the one by SELEX Collaboration. In addition, we predict the pion-baryon and strangeness-baryon sigma terms, as well as the mass splitting between the Ξc c and Ωc c states. Their quark mass dependences are also discussed. The numerical procedure can be applied to the chiral results of O (p4) order, where more unknown constants are involved, when more data are available for unphysical pion masses.

Intrinsic charm and charmed particle production at Serpukhov energies

International Nuclear Information System (INIS)

Zmushko, V.V.

1995-01-01

This paper presents a study of the charmed particle production by protons on nuclei in the framework of two-component model at the Serpukhov energies. This model combines the leading-twist QCD and intrinsic charm contributions. It is shown that both contributions are comparable at 70 GeV energy of a proton, which makes possible the testing of the intrinsic charm predictions: the asymmetry between the leading and non-leading charm production and the A dependence of charm production. The asymmetry for D-bar/D mesons and Λ c + /Λ c - baryons and the cross section ratios for different nuclei are estimated [ru

First measurement of the lifetime of the doubly charmed baryon $\\Xi_{cc}^{++}$

CERN Document Server

Aaij, Roel; LHCb Collaboration; Adinolfi, Marco; Aidala, Christine Angela; Ajaltouni, Ziad; Akar, Simon; Albicocco, Pietro; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Alfonso Albero, Alejandro; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Andreassi, Guido; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Archilli, Flavio; d'Argent, Philippe; Arnau Romeu, Joan; Artamonov, Alexander; Artuso, Marina; Arzymatov, Kenenbek; Aslanides, Elie; Atzeni, Michele; Audurier, Benjamin; Bachmann, Sebastian; Back, John; Baker, Sophie; Balagura, Vladislav; Baldini, Wander; Baranov, Alexander; Barlow, Roger; Barsuk, Sergey; Barter, William; Baryshnikov, Fedor; Batozskaya, Varvara; Batsukh, Baasansuren; Battista, Vincenzo; Bay, Aurelio; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Beiter, Andrew; Bel, Lennaert; Beliy, Nikita; Bellee, Violaine; Belloli, Nicoletta; Belous, Konstantin; 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Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Pereima, Dmitrii; Perret, Pascal; Pescatore, Luca; Petridis, Konstantinos; Petrolini, Alessandro; Petrov, Aleksandr; Petrucci, Stefano; Petruzzo, Marco; Pietrzyk, Boleslaw; Pietrzyk, Guillaume; Pikies, Malgorzata; Pili, Martina; Pinci, Davide; Pinzino, Jacopo; Pisani, Flavio; Piucci, Alessio; Placinta, Vlad-Mihai; Playfer, Stephen; Plews, Jonathan; Plo Casasus, Maximo; Polci, Francesco; Poli Lener, Marco; Poluektov, Anton; Polukhina, Natalia; Polyakov, Ivan; Polycarpo, Erica; Pomery, Gabriela Johanna; Ponce, Sebastien; Popov, Alexander; Popov, Dmitry; Poslavskii, Stanislav; Potterat, Cédric; Price, Eugenia; Prisciandaro, Jessica; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Pullen, Hannah Louise; Punzi, Giovanni; Qian, Wenbin; Qin, Jia-Jia; Quagliani, Renato; Quintana, Boris; Rachwal, Bartlomiej; Rademacker, Jonas; Rama, Matteo; Ramos Pernas, Miguel; Rangel, Murilo; Ratnikov, Fedor; Raven, Gerhard; Ravonel Salzgeber, Melody; Reboud, Meril; Redi, Federico; Reichert, Stefanie; dos Reis, Alberto; Reiss, Florian; Remon Alepuz, Clara; Ren, Zan; Renaudin, Victor; Ricciardi, Stefania; Richards, Sophie; Rinnert, Kurt; Robbe, Patrick; Robert, Arnaud; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Roehrken, Markus; Rogozhnikov, Alexey; Roiser, Stefan; Rollings, Alexandra Paige; Romanovskiy, Vladimir; Romero Vidal, Antonio; Rotondo, Marcello; Rudolph, Matthew Scott; Ruf, Thomas; Ruiz Vidal, Joan; Saborido Silva, Juan Jose; Sagidova, Naylya; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Gras, Cristina; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santimaria, Marco; Santovetti, Emanuele; Sarpis, Gediminas; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saur, Miroslav; Savrina, Darya; Schael, Stefan; Schellenberg, Margarete; Schiller, Manuel; Schindler, Heinrich; Schmelling, Michael; Schmelzer, Timon; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schreiner, HF; Schubiger, Maxime; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sepulveda, Eduardo Enrique; Sergi, Antonino; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seuthe, Alex; Seyfert, Paul; Shapkin, Mikhail; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shmanin, Evgenii; Siddi, Benedetto Gianluca; Silva Coutinho, Rafael; Silva de Oliveira, Luiz Gustavo; Simi, Gabriele; Simone, Saverio; Skidmore, Nicola; Skwarnicki, Tomasz; Smeaton, John Gordon; Smith, Eluned; Smith, Iwan Thomas; Smith, Mark; Soares, Marcelo; Soares Lavra, Lais; Sokoloff, Michael; Soler, Paul; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Stefko, Pavol; Stefkova, Slavomira; Steinkamp, Olaf; Stemmle, Simon; Stenyakin, Oleg; Stepanova, Margarita; Stevens, Holger; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Stramaglia, Maria Elena; Straticiuc, Mihai; Straumann, Ulrich; Strokov, Sergey; Sun, Jiayin; Sun, Liang; Swientek, Krzysztof; Syropoulos, Vasileios; Szumlak, Tomasz; Szymanski, Maciej Pawel; T'Jampens, Stephane; Tang, Zhipeng; Tayduganov, Andrey; Tekampe, Tobias; Tellarini, Giulia; Teubert, Frederic; Thomas, Eric; van Tilburg, Jeroen; Tilley, Matthew James; Tisserand, Vincent; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Tou, Da Yu; Tourinho Jadallah Aoude, Rafael; Tournefier, Edwige; Traill, Murdo; Tran, Minh Tâm; Trisovic, Ana; Tsaregorodtsev, Andrei; Tuci, Giulia; Tully, Alison; Tuning, Niels; Ukleja, Artur; Usachov, Andrii; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagner, Alexander; Vagnoni, Vincenzo; Valassi, Andrea; Valat, Sebastien; Valenti, Giovanni; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vecchi, Stefania; van Veghel, Maarten; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Venkateswaran, Aravindhan; Verlage, Tobias Anton; Vernet, Maxime; Veronesi, Michele; Veronika, Naomi; Vesterinen, Mika; Viana Barbosa, Joao Vitor; Vieira, Daniel; Vieites Diaz, Maria; Viemann, Harald; Vilasis-Cardona, Xavier; Vitkovskiy, Arseniy; Vitti, Marcela; Volkov, Vladimir; Vollhardt, Achim; Voneki, Balazs; Vorobyev, Alexey; Vorobyev, Vitaly; de Vries, Jacco; Vázquez Sierra, Carlos; Waldi, Roland; Walsh, John; Wang, Jianchun; Wang, Mengzhen; Wang, Yilong; Wang, Zhenzi; Ward, David; Wark, Heather Mckenzie; Watson, Nigel; Websdale, David; Weiden, Andreas; Weisser, Constantin; Whitehead, Mark; Wicht, Jean; Wilkinson, Guy; Wilkinson, Michael; Williams, Ifan; Williams, Mark Richard James; Williams, Mike; Williams, Timothy; Wilson, Fergus; Wimberley, Jack; Winn, Michael Andreas; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wyllie, Kenneth; Xiao, Dong; Xie, Yuehong; Xu, Ao; Xu, Menglin; Xu, Qingnian; Xu, Zehua; Xu, Zhirui; Yang, Zhenwei; Yang, Zishuo; Yao, Yuezhe; Yeomans, Lauren Emma; Yin, Hang; Yu, Jiesheng; Yuan, Xuhao; Yushchenko, Oleg; Zarebski, Kristian Alexander; Zavertyaev, Mikhail; Zhang, Dongliang; Zhang, Liming; Zhang, Wen Chao; Zhang, Yanxi; Zhelezov, Alexey; Zheng, Yangheng; Zhu, Xianglei; Zhukov, Valery; Zonneveld, Jennifer Brigitta; Zucchelli, Stefano

2018-01-01

The first measurement of the lifetime of the doubly charmed baryon $\\Xi_{cc}^{++}$ is presented, with the signal reconstructed in the final state $\\Lambda_c^+ K^- \\pi^+ \\pi^+$. The data sample used corresponds to an integrated luminosity of $1.7\\,\\mathrm{fb}^{-1}$, collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of $13\\mathrm{\\,Te\\kern -0.1em V}$. The $\\Xi_{cc}^{++}$ lifetime is measured to be $0.256\\,^{+0.024}_{-0.022}{\\,\\rm (stat)\\,} \\pm 0.014 {\\,\\rm(syst)}\\mathrm{\\,ps}$.

Odd-parity light baryon resonances

International Nuclear Information System (INIS)

Gamermann, D.; Garcia-Recio, C.; Salcedo, L. L.; Nieves, J.

2011-01-01

We use a consistent SU(6) extension of the meson-baryon chiral Lagrangian within a coupled channel unitary approach in order to calculate the T matrix for meson-baryon scattering in the s wave. The building blocks of the scheme are the π and N octets, the ρ nonet and the Δ decuplet. We identify poles in this unitary T matrix and interpret them as resonances. We study here the nonexotic sectors with strangeness S=0, -1, -2, -3 and spin J=(1/2), (3/2) and (5/2). Many of the poles generated can be associated with known N, Δ, Σ, Λ, Ξ and Ω resonances with negative parity. We show that most of the low-lying three and four star odd-parity baryon resonances with spin (1/2) and (3/2) can be related to multiplets of the spin-flavor symmetry group SU(6). This study allows us to predict the spin-parity of the Ξ(1620), Ξ(1690), Ξ(1950), Ξ(2250), Ω(2250) and Ω(2380) resonances, which have not been determined experimentally yet.

Heavy flavor baryons in hypercentral model

Indian Academy of Sciences (India)

Keywords. Hypercentral constituent quark model; charmed and beauty baryons; hyper-Coulomb plus power potential. Abstract. Heavy flavor baryons containing single and double charm (beauty) quarks with light flavor combinations are studied using the hypercentral description of the three-body problem. The confinement ...

Observation of Exclusive {ital B} Decays to Final States Containing a Charmed Baryon

Energy Technology Data Exchange (ETDEWEB)

Fu, X.; Nemati, B.; Richichi, S.J.; Ross, W.R.; Skubic, P.; Wood, M. [University of Oklahoma, Norman, Oklahoma 73019 (United States); Bishai, M.; Fast, J.; Gerndt, E.; Hinson, J.W.; Miao, T.; Miller, D.H.; Modesitt, M.; Shibata, E.I.; Shipsey, I.P.; Wang, P.N. [Purdue University, West Lafayette, Indiana 47907 (United States); Gibbons, L.; Johnson, S.D.; Kwon, Y.; Roberts, S.; Thorndike, E.H. [University of Rochester, Rochester, New York 14627 (United States); Jessop, C.P.; Lingel, K.; Marsiske, H.; Perl, M.L.; Schaffner, S.F.; Wang, R. [Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 (United States); Coan, T.E.; Dominick, J.; Fadeyev, V.; Korolkov, I.; Lambrecht, M.; Sanghera, S.; Shelkov, V.; Stroynowski, R.; Volobouev, I.; Wei, G. [Southern Methodist University, Dallas, Texas 75275 (United States); Artuso, M.; Efimov, A.; Gao, M.; Goldberg, M.; He, D.; Horwitz, N.; Kopp, S.; Moneti, G.C.; Mountain, R.; Mukhin, Y.; Playfer, S.; Skwarnicki, T.; Stone, S.; Xing, X. [Syracuse University, Syracuse, New York 13244 (United States); Bartelt, J.; Csorna, S.E.; Jain, V.; Marka, S. [Vanderbilt University, Nashville, Tennessee 37235 (United States); Freyberger, A.; Gibaut, D.; Kinoshita, K.; Pomianowski, P.; Schrenk, S. [Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 (United States); Cinabro, D. [Wayne State University, Detroit, Michigan 48202 (United States); Barish, B.; Chadha, M.; Chan, S.; Eigen, G.; Miller, J.S.; OGrady, C.; Schmidtler, M.; Urheim, J.; Weinstein, A.J.; Wuerthwein, F. [California Institute of Technology, Pasadena, California 91125 (United States); Asner, D.M.; Athanas, M.; Bliss, D.W.; Brower, W.S.; Masek, G.; Paar, H.P. [University of California, San Diego, La Jolla, California 92093 (United States); Gronberg, J.; Korte, C.M.; Kutschke, R.; Menary, S.; Morrison, R.J.; Nakanishi, S.; Nelson, H.N.; Nelson, T.K.; Qiao, C.; Richman, J.D.; Roberts, D.; Ryd, A.; and others

1997-10-01

Using data collected in the region of the {Upsilon}(4S) resonance with the CLEO-II detector, we report on the first observation of exclusive decays of the B meson to final states with a charmed baryon. We have measured the branching fractions B(B{sup {minus}}{r_arrow}{Lambda}{sup +}{sub c}{ovr p}{pi}{sup {minus}})=( 0.62{sup +0.23}{sub {minus}0.20}{plus_minus}0.11{plus_minus}0.10) {times}10{sup {minus}3} and B({ovr B}{sup 0}{r_arrow}{Lambda}{sup +}{sub c}{ovr p}{pi}{sup +}{pi}{sup {minus}})=(1.33{sup +0.46}{sub {minus}0.42}{plus_minus}0.31{plus_minus}0.21){times}10{sup {minus}3} , where the first error is statistical, the second is systematic, and the third is due to uncertainty in the {Lambda}{sup +}{sub c} branching fractions. In addition, we report upper limits for final states of the form {ovr B}{r_arrow}{Lambda}{sup +}{sub c}{ovr p} (n{pi}) and {Lambda}{sup +}{sub c}{ovr p}(n{pi}) {pi}{sup 0} , where (n{pi}) denotes up to four charged pions. {copyright} {ital 1997} {ital The American Physical Society}

Magnetic moments of triply heavy baryons in quark-diquark model

International Nuclear Information System (INIS)

Thakkar, Kaushal; Majethiya, Ajay; Vinodkumar, P.C.

2016-01-01

Along with the well-established triply flavoured (uuu) and strange (sss) baryons, QCD predicts similar states made up of charm quarks, the triply-charmed baryon, ccc and bottom quarks, the triply-bottom baryon, bbb. Such a state has yet to be observed experimentally. After the observation of the doubly charmed baryon by the SELEX group, it is expected that the triply heavy flavour baryonic state may be in the offing very soon. Though considerable amount of data on the properties of the singly-heavy baryons are available in literature, only sparse attention has been paid to the spectroscopy of double and triple-heavy flavour baryons, perhaps mainly due to the lack of experimental incentives

Heavy baryons

International Nuclear Information System (INIS)

Koerner, J.G.

1994-06-01

We review the experimental and theoretical status of baryons containing one heavy quark. The charm and bottom baryon states are classified and their mass spectra are listed. The appropriate theoretical framework for the description of heavy baryons is the Heavy Quark Effective Theory, whose general ideas and methods are introduced and illustrated in specific examples. We present simple covariant expressions for the spin wave functions of heavy baryons including p-wave baryons. The covariant spin wave functions are used to determine the Heavy Quark Symmetry structure of flavour-changing current-induced transitions between heavy baryons as well as one-pion and one-photon transitions between heavy baryons of the same flavour. We discuss 1/m Q corrections to the current-induced transitions as well as the structure of heavy to light baryon transitions. Whenever possible we attempt to present numbers to compare with experiment by making use of further model-dependent assumptions as e.g. the constituent picture for light quarks. We highlight recent advances in the theoretical understanding of the inclusive decays of hadrons containing one heavy quark including polarization. For exclusive semileptonic decays we discuss rates, angular decay distributions and polarization effects. We provide an update of the experimental and theoretical status of lifetimes of heavy baryons and of exclusive nonleptonic two body decays of charm baryons. (orig.)

Isospin splittings of baryons

International Nuclear Information System (INIS)

Varga, Kalman; Genovese, Marco; Richard, Jean-Marc; Silvestre-Brac, Bernard

1998-01-01

We discuss the isospin-breaking mass differences among baryons, with particular attention in the charm sector to the Σ c + -Σ c 0 , Σ c ++ -Σ c 0 , and Ξ c + -Ξ c 0 splittings. Simple potential models cannot accommodate the trend of the available data on charm baryons. More precise measurements would offer the possibility of testing how well potential models describe the non-perturbative limit of QCD

Study of exclusive B decays to charmed baryons

International Nuclear Information System (INIS)

Gabyshev, N.; Kichimi, H.; Abe, K.; Adachi, I.; Gershon, T.; Haba, J.; Hazumi, M.; Igarashi, Y.; Itoh, R.; Iwasaki, H.; Iwasaki, Y.; Katayama, N.; Nakao, M.; Ozaki, H.; Sagawa, H.; Saitoh, S.; Sakai, Y.; Sumisawa, K.; Suzuki, K.; Takasaki, F.

2002-01-01

Using 29.1 fb -1 of data accumulated at the Υ(4S) with the Belle detector at KEKB, we have studied the decay modes B-bar 0 →Λ c + p-barπ + π - , B - →Λ c + p-barπ - , and B-bar 0 →Λ c + p-bar. We report branching fractions of exclusive B decays to charmed baryons with four-, three- and two-body final states, including intermediate Σ c ++ and Σ c 0 states. We observed B-bar 0 →Σ c (2455) ++ p-barπ - for the first time with a branching fraction of (2.38 -0.55 +0.63 ±0.41±0.62)x10 -4 and observed evidence for the two-body decay B - →Σ c (2455) 0 p-bar with a branching fraction of (0.45 -0.19 +0.26 ±0.07±0.12)x10 -4 . We also set improved upper limits for the two-body decays B-bar 0 →Λ c + p-bar and B-bar - →Σ c (2520) 0 p-bar

Resolving the SELEX--LHCb Double-Charm Baryon Conflict: The Impact of Intrinsic Heavy-Quark Hadroproduction and Supersymmetric Light-Front Holographic QCD

Energy Technology Data Exchange (ETDEWEB)

Brodsky, Stanley [SLAC National Accelerator Lab., Menlo Park, CA (United States)

2017-01-01

In this paper we show that the intrinsic heavy-quark QCD mechanism for the hadroproduction of heavy hadrons at large $x_F$ can resolve the apparent conflict between measurements of double-charm baryons by the SELEX fixed-target experiment and the LHCb experiment at the LHC collider. We show that both experiments are compatible, and that both results can be correct. The observed spectroscopy of double-charm hadrons is in agreement with the predictions of supersymmetric light front holographic QCD.

Masses of charmed particles, decay modes and lifetimes

International Nuclear Information System (INIS)

Vajsenberg, A.O.

1982-01-01

Basic characteristics of charmed particles obtained up to the middle of 1981 are discussed in the survey. Stated in brief are main predictions of the theory on charmed particles properties. Experimental data on masses, decay modes and lifetimes of D and F mesons as well as charmed baryons are considered. Basic experiments are described. It is pointed out that in the experiments single and pair production events as well as charmed particle decay have been observed. The charmed particles lifetime lies within the limits of 10 -12 - 10 -13 C. The lifetime of D +- mesons is approximately three times longer than the D 0 mesons lifetime. The lifetime of F mesons and Λsub(e) baryons is close to D 0 mesons lifetime [ru

A Cicerone for the Physics of Charm

OpenAIRE

Bianco, S.; Fabbri, F. L.; Benson, D.; Bigi, I.

2003-01-01

After briefly recapitulating the history of the charm quantum number we sketch the experimental environments and instruments employed to study the behaviour of charm hadrons and then describe the theoretical tools for treating charm dynamics. We discuss a wide range of inclusive production processes before analyzing the spectroscopy of hadrons with hidden and open charm and the weak lifetimes of charm mesons and baryons. Then we address leptonic, exclusive semileptonic and nonleptonic charm d...

Exotic quantum states for charmed baryons at finite temperature

Directory of Open Access Journals (Sweden)

Jiaxing Zhao

2017-12-01

Full Text Available The significantly screened heavy-quark potential in hot medium provides the possibility to study exotic quantum states of three-heavy-quark systems. By solving the Schrödinger equation for a three-charm-quark system at finite temperature, we found that, there exist Borromean states which might be realized in high energy nuclear collisions, and the binding energies of the system satisfy precisely the scaling law for Efimov states in the resonance limit.

Multivariate Analysis Techniques for charm reconstruction with ALICE

CERN Multimedia

CERN. Geneva

2018-01-01

ALICE is the experiment at the LHC dedicated to heavy-ion collisions. One of the key tools to investigate the strongly-interacting medium (Quark-Gluon Plasma, QGP) formed in heavy-ion collisions is the measurement of open-charm particle production. In particular, charmed baryons, such as ΛC, provide essential information for the understanding of charm thermalisation and hadronisation in the QGP. Data from proton-proton and proton-Pb collisions are needed as a reference for interpreting the results in Pb-Pb collisions, as well as to study charm hadronisation into baryons "in-vacuum". The relatively short lifetime of the ΛC baryon, cτ~60μm, makes the reconstruction of its decay a challenging task that profits from the excellent performance of ALICE in terms of secondary vertex reconstruction and particle identification. The application of multivariateanalysis (MVA) techniques through Boosted Decision Trees can facilitate the separation of the ΛC signal from the background, and as such be a complementary ap...

Search for the Charmed Strange Baryon A$^{o}$

CERN Multimedia

2002-01-01

The aim of the experiment is to search for inclusive production of the charmed strange baryon A|0 using @S|- with a momentum of 135 GeV/c on a Be-target. A|0 with lab-momenta between 70-120 GeV/c will be accepted, corresponding to X(A|0) $>$ 0.5. \\\\ \\\\ The apparatus is a modified version of the one used for WA42. The incoming @S|- are identified by a DISC Cerenkov counter. The A|0 detection is restricted to decay channels which contains only charged particles in the final state (e.g. A|0 @A @L K|-@p|+). \\\\ \\\\ The decay products are analysed in a magnetic spectrometer equipped with multiwire proportional chambers (B,C,D,E) and drift chambers (DC). Two multicell gas Cerenkov counters (C1,C2) allow the separation of K's and p's from @p's. A second magnet (SM2) reduces the geometrical overlap of @p's and heavier particles in the Cerenkov counters due to their different momentum spectra. The scintillator hodoscopes H^4 and H^5 and the chambers E and F behind SM2 allow a geometrical correlation of tracks with the C...

Baryon resonances in nuclei

International Nuclear Information System (INIS)

Arenhoevel, H.

1977-01-01

The field of baryon resonances in nuclei is reviewed. Theoretical developments and experimental evidence as well are discussed. Special emphasis is laid on electromagnetic processes for the two nucleon system. Some aspects of real isobars in nuclei are touched upon. (orig.) [de

Missing baryonic resonances in the Hagedorn spectrum

Energy Technology Data Exchange (ETDEWEB)

Man Lo, Pok [University of Wroclaw, Institute of Theoretical Physics, Wroclaw (Poland); GSI, Extreme Matter Institute EMMI, Darmstadt (Germany); Marczenko, Michal; Sasaki, Chihiro [University of Wroclaw, Institute of Theoretical Physics, Wroclaw (Poland); Redlich, Krzysztof [University of Wroclaw, Institute of Theoretical Physics, Wroclaw (Poland); GSI, Extreme Matter Institute EMMI, Darmstadt (Germany); Duke University, Department of Physics, Durham, NC (United States)

2016-08-15

The hadronic medium of QCD is modeled as a gas of point-like hadrons, with its composition determined by the Hagedorn mass spectrum. The spectrum consists of a discrete and a continuous part. The former is determined by the experimentally confirmed resonances tabulated by the Particle Data Group (PDG), while the latter can be extracted from the existing lattice data. This formulation of the hadron resonance gas (HRG) provides a transparent framework to relate the fluctuation of conserved charges as calculated in the lattice QCD approach to the particle content of the medium. A comparison of the two approaches shows that the equation of state is well described by the standard HRG model, which includes only a discrete spectrum of known hadrons. The corresponding description in the strange sector, however, shows clear discrepancies, thus a continuous spectrum is added to incorporate the effect of missing resonances. We propose a method to extract the strange-baryon spectrum from the lattice data. The result is consistent with the trend set by the unconfirmed strange baryons resonances listed by the PDG, suggesting that most of the missing interaction strength for the strange baryons reside in the S = 1 sector. This scenario is also supported by recent lattice calculations, and might be important in the energy region covered by the NICA accelerator in Dubna, where in the heavy-ion collisions, baryons are the dominating degrees of freedom in the final state. (orig.)

On the intrinsic charm and the recombination mechanisms in charm hadron production

International Nuclear Information System (INIS)

Anjos, J.C.; Magnin, J.; Herrera, G.

2001-09-01

We study Λ c ± production in pN and π - N interactions. Recent experimental data from the SELEX and E791 Collaborations at FNAL provide important information on the production mechanism of charm hadrons. In particular, the production of the Λ c baryon provides a good test of the intrinsic charm and the recombination mechanisms, which have been proposed to explain the so called leading particle effects. (author)

Charm and beauty decays in the ALEPH experiment

International Nuclear Information System (INIS)

Boucrot, J.

1992-05-01

Results of the ALEPH experiment at LEP are presented on charm and beauty decays, from data taken in 1990 and 1991. Several exclusive channels of charm and beauty mesons are seen. Evidence is given for the production of beauty baryons from correlations between a high Pt lepton and a Λ 0 or a Λ c baryon. Finally, first evidence is given for the production of the strange B meson, from Ds-lepton correlations. (author) 7 refs., 7 figs

Charm and beauty decays in the ALEPH experiment

International Nuclear Information System (INIS)

Boucrot, J.

1992-01-01

Results of the ALEPH experiment at LEP are presented on charm and beauty decays, from data taken in 1990 and 1991. Several exclusive channels of charm and beauty mesons are seen. Evidence is given for the production of beauty baryons from correlations between a high Pt lepton and a Λ 0 or a Λ c baryon. Finally, first evidence is given for the production of the strange B meson, from Ds-lepton correlations. (author) 7 refs.; 7 figs

Non-charm hadronic decays of bottom baryons

International Nuclear Information System (INIS)

Kohara, Y.

1999-01-01

Two-body decay amplitudes of antitriplet bottom baryons Λ 0b , Θ 0 b and Θ -b to a decuplet baryon and a pseudoscalar meson are analyzed on the basis of the quark diagram scheme. Relations among the various decay rates to decuplet baryons are derived

From gauge theories to charm

International Nuclear Information System (INIS)

Jacob, Maurice

1976-01-01

The charm is a new elementary constituent introduced in the SU(4) framework to explain the properties of the psi particles; its introduction definites the essential properties of the four quarks, u, d, s, c in the SU(4) framework. The discovery of charmed particles (two mesons four quarks u,d,s,c in the SU(4) framework. The discovery of charmed particles (two mesons and one baryons) confirms a series of previsions that derive from the introduction of gauge theories: weak neutral currents, W meson, unification of weak interactions and electrodynamics. Beyonds charm the introduction of colored quarks and gluon exchanges gives to strong interactions the simplicity of electrodynamics [fr

Quark-level analogue of nuclear fusion with doubly heavy baryons.

Science.gov (United States)

Karliner, Marek; Rosner, Jonathan L

2017-11-01

The essence of nuclear fusion is that energy can be released by the rearrangement of nucleons between the initial- and final-state nuclei. The recent discovery of the first doubly charmed baryon , which contains two charm quarks (c) and one up quark (u) and has a mass of about 3,621 megaelectronvolts (MeV) (the mass of the proton is 938 MeV) also revealed a large binding energy of about 130 MeV between the two charm quarks. Here we report that this strong binding enables a quark-rearrangement, exothermic reaction in which two heavy baryons (Λ c ) undergo fusion to produce the doubly charmed baryon and a neutron n (), resulting in an energy release of 12 MeV. This reaction is a quark-level analogue of the deuterium-tritium nuclear fusion reaction (DT → 4 He n). The much larger binding energy (approximately 280 MeV) between two bottom quarks (b) causes the analogous reaction with bottom quarks () to have a much larger energy release of about 138 MeV. We suggest some experimental setups in which the highly exothermic nature of the fusion of two heavy-quark baryons might manifest itself. At present, however, the very short lifetimes of the heavy bottom and charm quarks preclude any practical applications of such reactions.

Measurement of the lifetime of the charm baryon ΛC

International Nuclear Information System (INIS)

Luecking, B.

1989-10-01

The results presented in this thesis are based on the analysis of the data taken by the ACCMOR Collaboration in the experiment NA 32 at the CERN Super Proton Synchrotron (SPS) in the years 1985/86. The experiment NA 32 is a fixed-target experiment with a high-resolution semiconductor vertex detector for the reconstruction of the charm production and decay vertices. The energy of the incident π-beam amounts to 230 GeV. A magnetic spectrometer allows the momentum measurement and particle identification of the charged particles arising in the interaction, beside altogether 15 silicon strip detectors two charge-coupled devices (CCD's) are the most important components of the vertex detector. NA 32 is the first experiment in high energy physics in which CCD's are applied as track detectors. The mean transverse measurement error of the reconstructed particle tracks amounts in the region of the target to about 5 μm in two together orthogonal directions. The analysis of altogether 17.1 million interactions recorded on magnetic tape yields about 1200 completely reconstructed decays of the charm particles D 0 , D + , D S , Λ C , and Ξ C + in altogether 22 different decay channels over a very low background. Six new, hitherto not yet observed decay channels were detected. For the measurement of the lifetime of the Λ C baryon about 100 Λ C →pK - π + decays are available over a background of 5%. A combined maximum-likelihood fit to the distribution of the invariant masses and the lifetime distribution corrected for the detector acceptance gives a mean Λ C lifetime of: τ=(2.03+0.28-0.03)x10 -13 s and a Λ C mass of: m=(2285.8±0.6±1.2) MeV/c 2 . (orig./HSI) [de

Multistrange Meson-Baryon Dynamics and Resonance Generation

Science.gov (United States)

Khemchandani, K. P.; Martínez Torres, A.; Hosaka, A.; Nagahiro, H.; Navarra, F. S.; Nielsen, M.

2018-05-01

In this talk I review our recent studies on meson-baryon systems with strangeness - 1 and - 2. The motivation of our works is to find resonances generated as a consequence of coupled channel meson-baryon interactions. The coupled channels are all meson-baryon systems formed by combining a pseudoscalar or a vector meson with an octet baryon such that the system has the strange quantum number equal to - 1 or - 2. The lowest order meson-baryon interaction amplitudes are obtained from Lagrangians based on the chiral and the hidden local symmetries related to the vector mesons working as the gauge bosons. These lowest order amplitudes are used as an input to solve the Bethe-Salpeter equation and a search for poles is made in the resulting amplitudes, in the complex plane. In case of systems with strangeness - 1, we find evidence for the existence of some hyperons such as: Λ(2000), Σ(1750), Σ(1940), Σ(2000). More recently, in the study of strangeness - 2 systems we have found two narrow resonances which can be related to Ξ (1690) and Ξ(2120). In this latter work, we have obtained the lowest order amplitudes relativistically as well as in the nonrelativistic approximation to solve the scattering equations. We find that the existence of the poles in the complex plane does not get affected by the computation of the scattering equation with the lowest order amplitudes obtained in the nonrelativistic approximation.

Hyperons, charm and beauty hadrons: Conclusion and outlook

International Nuclear Information System (INIS)

Bernabeu, Jose

2001-01-01

In this concluding talk, the advances in the Flavour Problem studies are discussed, following the structure of the presentations in the Conference. The subjects touched are organized as follows: Baryons, K-physics, Charm and Beauty production, Charm and Beauty decays, B-Mixing and CP-Violation, Heavy Quarkonium

Charm counting in b decays

CERN Document Server

Buskulic, Damir; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Nief, J Y; Odier, P; Pietrzyk, B; Casado, M P; Chmeissani, M; Crespo, J M; Delfino, M C; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Carrido, L; Juste, A; Martínez, M; Orteu, S; Padilla, C; Park, I C; Pascual, A; Perlas, J A; Riu, I; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Alemany, R; Bazarko, A O; Bonvicini, G; Bright-Thomas, P G; Cattaneo, M; Cerutti, F; Comas, P; Coyle, P; Drevermann, H; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Lutters, G; Martin, E B; Mato, P; Minten, Adolf G; Miquel, R; Mir, L M; Moneta, L; Oest, T; Pacheco, A; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rizzo, G; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schmitt, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wagner, A; Ajaltouni, Ziad J; Barrès, A; Boyer, C; Falvard, A; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rosnet, P; Rossignol, J M; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Kyriakis, A; Markou, C; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Rougé, A; Rumpf, M; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Casper, David William; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Dorris, S J; Halley, A W; Knowles, I G; Lynch, J G; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Teixeira-Dias, P; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Geweniger, C; Graefe, G; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Schmidt, M; Sommer, J; Tittel, K; Werner, S; Wunsch, M; Abbaneo, D; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Moutoussi, A; Nash, J; Sedgbeer, J K; Stacey, A M; Williams, M D; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Williams, M I; Galla, A; Giehl, I; Greene, A M; Hoffmann, C; Jakobs, K; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Bencheikh, A M; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Diaconu, C A; Etienne, F; Konstantinidis, N P; Payre, P; Rousseau, D; Talby, M; Sadouki, A; Thulasidas, M; Trabelsi, K; Aleppo, M; Ragusa, F; Bauer, C; Berlich, R; Blum, Walter; Büscher, V; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Stenzel, H; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Choi, Y; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Höcker, A; Jacholkowska, A; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Nikolic, I A; Park, H J; Schune, M H; Simion, S; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Vannini, C; Verdini, P G; Blair, G A; Bryant, L M; Chambers, J T; Gao, Y; Green, M G; Medcalf, T; Perrodo, P; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Maley, P; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Boswell, R; Brew, C A J; Cartwright, S L; Combley, F; Köksal, A; Lehto, M H; Newton, W M; Reeve, J; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Grupen, Claus; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Musolino, G; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Greening, T C; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Walsh, A M; Walsh, J; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

1996-01-01

The inclusive production of charmed particles in Z -> bb decays has been measured from the yield of D^0, D^+, D^+_s and Lambda_{c}^+ decays in a sample of qq events with high b purity collected with the ALEPH detector from 1992 to 1995. From these measurements, adding the charmonia production rate and an estimate of the charmed strange baryon contribution, the average number of charm quarks per b decay is determined to be n_c = 1.230 \\pm 0.036 \\pm 0.038 \\pm 0.053 where the uncertainties are due to statistics, systematic effects and branching ratios, respectively.

Charm counting in b decays

Science.gov (United States)

Buskulic, D.; de Bonis, I.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Lucotte, A.; Minard, M.-N.; Nief, J.-Y.; Odier, P.; Pietrzyk, B.; Casado, M. P.; Chmeissani, M.; Crespo, J. M.; Delfino, M.; Efthymiopoulos, I.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, Ll.; Juste, A.; Martinez, M.; Orteu, S.; Padilla, C.; Park, I. C.; Pascual, A.; Perlas, J. A.; Riu, I.; Sanchez, F.; Teubert, F.; Colaleo, A.; Creanza, D.; de Palma, M.; Gelao, G.; Girone, M.; Iaselli, G.; Maggi, G.; Maggi, M.; Marinelli, N.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Alemany, R.; Bazarko, A. O.; Bonvicini, G.; Bright-Thomas, P.; Cattaneo, M.; Cerutti, F.; Comas, P.; Coyle, P.; Drevermann, H.; Forty, R. W.; Frank, M.; Hagelberg, R.; Harvey, J.; Janot, P.; Jost, B.; Kneringer, E.; Knobloch, J.; Lehraus, I.; Lutters, G.; Martin, E. B.; Mato, P.; Minten, A.; Miquel, R.; Mir, Ll. M.; Moneta, L.; Oest, T.; Pacheco, A.; Pusztaszeri, J.-F.; Ranjard, F.; Rensing, P.; Rizzo, G.; Rolandi, L.; Schlatter, D.; Schmelling, M.; Schmitt, M.; Schneider, O.; Tejessy, W.; Tomalin, I. R.; Venturi, A.; Wachsmuth, H.; Wagner, A.; Ajaltouni, Z.; Barrès, A.; Boyer, C.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rosnet, P.; Rossignol, J.-M.; Fearnley, T.; Hansen, J. B.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Rensch, B.; Wäänänen, A.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Zachariadou, K.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Bourdon, P.; Rougé, A.; Rumpf, M.; Valassi, A.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Focardi, E.; Parrini, G.; Corden, M.; Georgiopoulos, C.; Jaffe, D. E.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Casper, D.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Dorris, S. J.; Halley, A. W.; Knowles, I. G.; Lynch, J. G.; O'Shea, V.; Raine, C.; Reeves, P.; Scarr, J. M.; Smith, K.; Teixeira-Dias, P.; Thompson, A. S.; Thomson, F.; Thorn, S.; Turnbull, R. M.; Becker, U.; Geweniger, C.; Graefe, G.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E. E.; Putzer, A.; Schmidt, M.; Sommer, J.; Stenzel, H.; Tittel, K.; Werner, S.; Wunsch, M.; Abbaneo, D.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Dornan, P. J.; Moutoussi, A.; Nash, J.; Sedgbeer, J. K.; Stacey, A. M.; Williams, M. D.; Dissertori, G.; Girtler, P.; Kuhn, D.; Rudolph, G.; Betteridge, A. P.; Bowdery, C. K.; Colrain, P.; Crawford, G.; Finch, A. J.; Foster, F.; Hughes, G.; Sloan, T.; Williams, M. I.; Galla, A.; Giehl, I.; Greene, A. M.; Hoffmann, C.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.-G.; van Gemmeren, P.; Zeitnitz, C.; Aubert, J. J.; Bencheikh, A. M.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Calvet, D.; Carr, J.; Diaconu, C.; Etienne, F.; Konstantinidis, N.; Payre, P.; Rousseau, D.; Talby, M.; Sadouki, A.; Thulasidas, M.; Trabelsi, K.; Aleppo, M.; Ragusa, F.; Bauer, C.; Berlich, R.; Blum, W.; Büscher, V.; Dietl, H.; Dydak, F.; Ganis, G.; Gotzhein, C.; Kroha, H.; Lütjens, G.; Lutz, G.; Männer, W.; Moser, H.-G.; Richter, R.; Rosado-Schlosser, A.; Schael, S.; Settles, R.; Seywerd, H.; Denis, R. St.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Boucrot, J.; Callot, O.; Choi, Y.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Höcker, A.; Jacholkowska, A.; Jacquet, M.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Nikolic, I.; Park, H. J.; Schune, M.-H.; Simion, S.; Veillet, J.-J.; Videau, I.; Zerwas, D.; Azzurri, P.; Bagliesi, G.; Batignani, G.; Bettarini, S.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M. A.; Ciulli, V.; Dell'Orso, R.; Fantechi, R.; Ferrante, I.; Foà, L.; Forti, F.; Giassi, A.; Giorgi, M. A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Sanguinetti, G.; Sciabà, A.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Vannini, C.; Verdini, P. G.; Blair, G. A.; Bryant, L. M.; Chambers, J. T.; Gao, Y.; Green, M. G.; Medcalf, T.; Perrodo, P.; Strong, J. A.; von Wimmersperg-Toeller, J. H.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Maley, P.; Norton, P. R.; Thompson, J. C.; Wright, A. E.; Bloch-Devaux, B.; Colas, P.; Emery, S.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.-F.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S. N.; Dann, J. H.; Johnson, R. P.; Kim, H. Y.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Booth, C. N.; Boswell, R.; Brew, C. A. J.; Cartwright, S.; Combley, F.; Koksal, A.; Letho, M.; Newton, W. M.; Reeve, J.; Thompson, L. F.; Böhrer, A.; Brandt, S.; Cowan, G.; Grupen, C.; Minguet-Rodriguez, J.; Rivera, F.; Saraiva, P.; Smolik, L.; Stephan, F.; Apollonio, M.; Bosisio, L.; Della Marina, R.; Giannini, G.; Gobbo, B.; Musolino, G.; Rothberg, J.; Wasserbaech, S.; Armstrong, S. R.; Elmer, P.; Feng, Z.; Ferguson, D. P. S.; Gao, Y. S.; González, S.; Grahl, J.; Greening, T. C.; Hayes, O. J.; Hu, H.; McNamara, P. A.; Nachtman, J. M.; Orejudos, W.; Pan, Y. B.; Saadi, Y.; Scott, I. J.; Walsh, A. M.; Walsh, J.; Wu, Sau Lan; Wu, X.; Yamartino, J. M.; Zheng, M.; Zobernig, G.; Aleph Collaboration

1996-02-01

The inclusive production of charmed particles in Z → b overlineb decays has been measured from the yield of D0, D+, Ds+ and Λc+ decays in a sample of q overlineq events with high b purity collected with the ALEPH detector from 1992 to 1995. From these measurements, adding the charmonia production rate and an estimate of the charmed strange baryon contribution, the average number of charm quarks per b decay is determined to be nc = 1.230 ± 0.036 ± 0.038 ± 0.053, where the uncertainties are due to statistics, systematic effects and branching ratios, respectively.

Charmed hadron production in pp collision

Science.gov (United States)

Goswami, Umananda Dev

2007-10-01

We investigated the production of charmed hadrons ( D+, D-, D0, D, Λc+, Λ¯c-) in pp collisions as a function of √{s}, xF, p⊥2 and p⊥ in the framework of the QGSJET model. The study of charmed hadron production characteristics in pp collision is particularly important for cosmic ray physics in the context of atmospheric prompt lepton fluxes. Here our aim is to check the reliability of the QGSJET model to be used to study the production of charmed hadrons in cosmic ray hadronic interactions with air nuclei. Charmed hadroproduction cross sections or the charmed hadron average multiplicities in pp collisions are relatively very small. The maximum production of all charmed hadrons takes place with low values of xF, p⊥2, and p⊥ within a small range for all values of √{s} under study. Charmed hadroproduction cross sections as a function of xF and p⊥2 are compared with the LEBC-EHS and LEBC-MPS experiment data for D-meson production. The agreement is quite satisfactory for smaller values of p⊥2 (⩽2 (GeV/c) 2). There is an asymmetry in charmed hadroproduction in pp collision. For all xF, asymmetry is prominent in the low value of √{s}. There is a strong preference for producing Λc+ rather than Λ¯c-baryons, while that for producing D¯ rather than D-mesons for this range of √{s}. Asymmetry increases from zero to ±1 around xF = 0.3 for all values of √{s} and for all charmed hardron groups. The patterns of asymmetric production of different charmed hadrons with xF are approximately the same as that with √{s}. We compare our calculation with the data from Fermilab experiment E781 (SELEX) for Λc-baryon production. The agreement is quite good. The asymmetry of charmed hadroproduction with p⊥ does not follow any well defined pattern.

Heavy baryon chiral perturbation theory and the spin 3/2 delta resonances

Energy Technology Data Exchange (ETDEWEB)

Kambor, J.

1996-12-31

Heavy baryon chiral perturbation theory is briefly reviewed, paying particular attention to the role of the spin 3/2 delta resonances. The concept of resonance saturation for the baryonic sector is critically discussed. Starting from a relativistic formulation of the pion-nucleon-delta system, the heavy baryon chiral Lagrangian including spin 3/2 resonances is constructed by means of a 1/m-expansion. The effective theory obtained admits a systematic expansion in terms of soft momenta, the pion mass M{sub {pi}} and the delta-nucleon mass difference {Delta}. (author). 22 refs.

Production of the charmed baryon Λc+ in neutron-proton interactions

International Nuclear Information System (INIS)

Vecko, M.; Novak, M.; Hladky, J.; Krasova, J.; Klabun, J.; Nowak, H.; Nowak, S.; Rysek, H.-E.; Abashidze, L.I.; Abesalashvili, L.N.; Amaglobeli, N.S.; Chasnikov, I.Ya; Kamburian, A.F.; Loktionov, A.A.; Nazarenko, V.D.; Potrebenikov, Yu.K.; Sliusareva, V.B.; Skorobogatova, V.I.

1989-01-01

The inclusive production was studied of charmed baryon Λ c + in interactions of 40 to 70 GeV/c neutrons with protons of a hydrogen target. The experiment was performed with the use of magnetic spectrometer BIS-2 located in the neutron beam of the Serpukhov accelerator. The signal of Λ c + was observed in the effective mass spectra of Λ 0 π + π + π - . After the removal of interactions occurring on the container of liquid hydrogen, the signal consisted of 14 combinations corresponding to ∼4 standard deviations of background. Its mean value was 2262 MeV/c 2 , the width of the bin containing signal was 20 MeV/c 2 . On the basis of this signal the value was determined of the cross section of Λ c + production times the branching ratio of its observed decay mode σxBr(Λ c + →Λ 0 π + π + π - ) = 0.26±0.11 μb in the kinematic region of x F >0.5 and p T <1 GeV/c. (author). 10 figs., 15 refs

Determining properties of baryon resonances in nuclei

International Nuclear Information System (INIS)

Johnson, M.B.; Chen, C.M.; Ernst, D.J.; Jiang, M.F.

1996-01-01

Meson-nucleus and photon-nucleus interactions are important sources of information about the medium modifications of baryon resonances in nuclei. Indications of how large the medium effects are for resonances above the Δ 33 (1232) are provided by it combined analysis of photonuclear and pion cross sections in the GeV range of energies. Tile existing data indicate a possible 10-20% renormalization of the pion coupling to higher-lying resonances in nuclei

Mass and Width Measurements of $\\Sigma_{c}$ Baryons

Energy Technology Data Exchange (ETDEWEB)

Vaandering, Eric Wayne [Colorado U.

2000-01-01

Analyses of several charmed baryons decaying to $\\Lambda^+_c$ are presented. The data for these analyses were collected by FOCUS, Fermilab Experiment E831. FOCUS is a high statistics charm photoproduction experiment and accumulated data during the 1996{1997 Fermilab Fixed Target run....

Calculation of baryon chemical potential and strangeness chemical potential in resonance matter

International Nuclear Information System (INIS)

Fu Yuanyong; Hu Shouyang; Lu Zhongdao

2006-01-01

Based on the high energy heavy-ion collisions statistical model, the baryon chemical potential and strangeness chemical potential are calculated for resonance matter with net baryon density and net strangeness density under given temperature. Furthermore, the relationship between net baryon density, net strangeness density and baryon chemical potential, strangeness chemical potential are analyzed. The results show that baryon chemical potential and strangeness chemical potential increase with net baryon density and net strangeness density increasing, the change of net baryon density affects baryon chemical potential and strangeness chemical potential more strongly than the change of net strangeness density. (authors)

New decay modes of the {Lambda}{sup +}{sub {ital c}} charmed baryon

Energy Technology Data Exchange (ETDEWEB)

Ammar, R.; Baringer, P.; Bean, A.; Besson, D.; Coppage, D.; Copty, N.; Davis, R.; Hancock, N.; Kelly, M.; Kotov, S.; Kravchenko, I.; Kwak, N.; Lam, H.; Kubota, Y.; Lattery, M.; Momayezi, M.; Nelson, J.K.; Patton, S.; Poling, R.; Savinov, V.; Schrenk, S.; Wang, R.; Alam, M.S.; Kim, I.J.; Ling, Z.; Mahmood, A.H.; O`Neill, J.J.; Severini, H.; Sun, C.R.; Wappler, F.; Crawford, G.; Daubenmier, C.M.; Fulton, R.; Fujino, D.; Gan, K.K.; Honscheid, K.; Kagan, H.; Kass, R.; Lee, J.; Sung, M.; White, C.; Wolf, A.; Zoeller, M.M.; Butler, F.; Fu, X.; Nemati, B.; Ross, W.R.; Skubic, P.; Wood, M.; Bishai, M.; Fast, J.; Gerndt, E.; Hinson, J.W.; McIlwain, R.L.; Miao, T.; Miller, D.H.; Modesitt, M.; Payne, D.; Shibata, E.I.; Shipsey, I.P.J.; Wang, P.N.; Battle, M.; Ernst, J.; Gibbons, L.; Kwon, Y.; Roberts, S.; Thorndike, E.H.; Wang, C.H.; Dominick, J.; Lambrecht, M.; Sanghera, S.; Shelkov, V.; Skwarnicki, T.; Stroynowski, R.; Volobouev, I.; Wei, G.; Zadorozhny, P.; Artuso, M.; Gao, M.; Goldberg, M.; He, D.; Horwitz, N.; Moneti, G.C.; Mountain, R.; Muheim, F.; Mukhin, Y.; Playfer, S.; Rozen, Y.; Stone, S.; Xing, X.; Zhu, G.; Bartelt, J.; Csorna, S.E.; Egyed, Z.; Jain, V.; Gibaut, D.; Kinoshita, K.; Pomianowski, P.; Barish, B.; Chadha, M.; Chan, S.; Cowen, D.F.; Eigen, G.; Miller, J.S.; O`Grady, C.; Urheim, J.; Weinstein, A.J.; Athanas, M.; Brower, W.; Masek, G.; Paar, H.P.; Gronberg, J.; Korte, C.M.; Kutschke, R.; Menary, S.; Morrison, R.J.; Nakanishi, S.; Nelson, H.N.; Nelson, T.K.; Qiao, C.; Richman, J.D.; Ryd, A.; Sperka, D.; Tajima, H.; Witherell, M.S.; Balest, R.; Cho, K.; Ford, W.T.; Johnson, D.R.; Lingel, K.; Lohner, M.; Rankin, P.; Smith, J.G.; Alexander, J.P.; Bebek, C.; Berkelman, K.; Bloom, K.; Browder, T.E.; Cassel, D.G.; Cho, H.A.; Coffman, D.M.; Crowcroft, D.S.; Drell, P.S.; Dumas, D.J.; Ehrlich, R.; Gaidarev, P.; Garcia-Sciveres, M.; Geiser, B.; Gittelman, B.; Gray, S.W.; Hartill, D.L.; Heltsley, B.K.; Henderson, S.; Jones, C.D.; Jones, S.L.; (CLEO Collaboration)

1995-05-01

We have observed five new decay modes of the charmed baryon {Lambda}{sup +}{sub {ital c}} using data collected with the CLEO II detector. Four decay modes, {Lambda}{sup +}{sub {ital c}}{r_arrow}{ital p{bar K}}{sup 0}{eta}, {Lambda}{eta}{pi}{sup +}, {Sigma}{sup +}{eta}, and {Sigma}{sup *+}{eta}, are first observations of final states with an {eta} meson, while the fifth mode, {Lambda}{sup +}{sub {ital c}}{r_arrow}{Lambda}{ital {bar K}}{sup 0}{ital K}{sup +}, requires the creation of an {ital s{bar s}} quark pair. We measure the branching fractions of these modes relative to {Lambda}{sup +}{sub {ital c}}{r_arrow}{ital pK}{sup -}{pi}{sup +} to be 0.25{plus_minus}0.04{plus_minus}0.04, 0.35{plus_minus}0.05{plus_minus}0.06, 0.11{plus_minus}0.03{plus_minus}0.02, 0.17{plus_minus}0.04{plus_minus}0.03, and 0.12{plus_minus}0.02{plus_minus}0.02, respectively.

The Monte-Carlo code DECAY to simulate the decay of baryon and meson resonances

International Nuclear Information System (INIS)

Haenssgen, K.; Ritter, S.

1983-01-01

The code DECAY simulates the decay of unpolarized baryon and meson resonances in the laboratory frame. DECAY treats some resonances among these all baryon resonances of the spin 3/2 + decuplet and all meson resonances of the spin 1 - nonet. A given resonance decays via two or three particle decay steps until all decay products are stable particles. Program summary and code description are given. (author)

SU(3) flavour symmetry breaking and charmed states

Energy Technology Data Exchange (ETDEWEB)

Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Najjar, J. [Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Nakamura, Y. [RIKEN Advanced Institute for Computational Science, Hyogo (Japan); Perlt, H.; Schiller, A. [Leipzig Univ. (Germany). Inst. fuer Theoretische Physik; Pleiter, D. [Forschungszentrum Juelich GmbH (Germany). Juelich Supercomputing Centre (JSC); Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Div.; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Stueben, H. [Hamburg Univ. (Germany). Regionales Rechenzentrum; Zanotti, J.M. [Adelaide Univ. (Australia). CSSM, School of Chemistry and Physics; Collaboration: QCDSF-UKQCD Collaborations

2013-11-15

By extending the SU(3) flavour symmetry breaking expansion from up, down and strange sea quark masses to partially quenched valence quark masses we propose a method to determine charmed quark hadron masses including possible QCD isospin breaking effects. Initial results for some open charmed pseudoscalar meson states and singly and doubly charmed baryon states are encouraging and demonstrate the potential of the procedure. Essential for the method is the determination of the scale using singlet quantities, and to this end we also give here a preliminary estimation of the recently introduced Wilson flow scales.

Strangeness and charm production in nucleus-nucleus collisions at beam energies near the thresholds

International Nuclear Information System (INIS)

Senger, P.

2001-01-01

The creation of strangeness and charm in nucleus-nucleus collisions at threshold beam energies is discussed as a probe for compressed baryonic matter. Experimental data on strangeness production at SIS energies indicate that the properties of kaons and antikaons are modified in the dense nuclear medium. An experiment is proposed to explore the QCD phase diagram in the region of highest baryon densities. An important observable will be charm production close to threshold. (orig.)

Time delayed K sup + N reactions and exotic baryon resonances

CERN Document Server

Kelkar, N G; Khemchandani, K P

2003-01-01

Evidence and hints, from both the theoretical and experimental sides, of exotic baryon resonances with B = S, have been with us for the last 30 years. The poor status of the general acceptance of these Z* resonances is partly due to the prejudice against penta-quark baryons and partly due to the opinion that a proof of the existence of exotic states must be rigorous. This can refer to the quality and amount of data gathered, and also to the analytical methods applied in the study of these resonances. It then seems mandatory that all possibilities and aspects be exploited. We do that by analysing the time delay in K sup + N scattering, encountering clear signals of the exotic Z* resonances close to the pole values found in partial wave analyses.

Hadron Physics at the Charm and Bottom Thresholds and Other Novel QCD Physics Topics at the NICA Accelerator Facility

Energy Technology Data Exchange (ETDEWEB)

Brodsky, Stanley J.; /SLAC

2012-06-20

The NICA collider project at the Joint Institute for Nuclear Research in Dubna will have the capability of colliding protons, polarized deuterons, and nuclei at an effective nucleon-nucleon center-of mass energy in the range {radical}s{sub NN} = 4 to 11 GeV. I briefly survey a number of novel hadron physics processes which can be investigated at the NICA collider. The topics include the formation of exotic heavy quark resonances near the charm and bottom thresholds, intrinsic strangeness, charm, and bottom phenomena, hidden-color degrees of freedom in nuclei, color transparency, single-spin asymmetries, the RHIC baryon anomaly, and non-universal antishadowing.

The charm of the proton and the Λc+

International Nuclear Information System (INIS)

Anjos, J. dos; Magnin, J.; Simao, F.R.A.; Herrera, G.

1997-01-01

We propose a two component model for charmed baryon production in pp collisions consisting of the conventional parton fusion mechanism and fragmentation plus quarks recombination in which a ud valence diquark from the proton recombines with a c-sea quark to produce a Λ c + . Our two-component model is compared with the intrinsic charm two-component model and experimental data. (author)

Observation of Two Excited Charmed Baryons Decaying into {Lambda}{sup +}{sub {ital c}}{pi}{sup {plus_minus}}

Energy Technology Data Exchange (ETDEWEB)

Brandenburg, G.; Briere, R.A.; Kim, D.Y.; Liu, T.; Saulnier, M.; Wilson, R.; Yamamoto, H. [Harvard University, Cambridge, Massachusetts 02138 (United States); Browder, T.E.; Li, F.; Li, Y.; Rodriguez, J.L. [University of Hawaii at Manoa, Honolulu, Hawaii 96822 (United States); Bergfeld, T.; Eisenstein, B.I.; Ernst, J.; Gladding, G.E.; Gollin, G.D.; Johnson, E.; Karliner, I.; Palmer, M.; Selen, M.; Thaler, J.J. [University of Illinois, Champaign-Urbana, Illinois 61801 (United States); Edwards, K.W. [Carleton University, Ottawa, Ontario, Canada K1S 5B6 and the Institute of Particle Physics (Canada); Bellerive, A.; Britton, D.I.; Janicek, R.; MacFarlane, D.B.; McLean, K.W.; Patel, P.M. [McGill University, Montreal, Quebec, Canada H3A 2T8 and the Institute of Particle Physics (Canada); Sadoff, A.J. [Ithaca College, Ithaca, New York 14850 (United States); Ammar, R.; Baringer, P.; Bean, A.; Besson, D.; Coppage, D.; Darling, C.; Davis, R.; Hancock, N.; Kotov, S.; Kravchenko, I.; Kwak, N. [University of Kansas, Lawrence, Kansas 66045 (United States); Anderson, S.; Kubota, Y.; Lattery, M.; ONeill, J.J.; Patton, S.; Poling, R.; Riehle, T.; Smith, A.; Savinov, V. [University of Minnesota, Minneapolis, Minnesota 55455 (United States); Alam, M.S.; Athar, S.B.; Ling, Z.; Mahmood, A.H.; Severini, H.; Timm, S.; Wappler, F. [State University of New York at Albany, Albany, New York 12222 (United States); Anastassov, A.; Blinov, S.; Duboscq, J.E.; Fulton, R.; Fujino, D.; Gan, K.K.; Hart, T.; Honscheid, K.; Kagan, H.; Kass, R.; Lee, J.; Sung, M.; Undrus, A.; Wanke, R.; Wolf, A.; Zoeller, M.M. [Ohio State University, Columbus, Ohio 43210 (United States); Nemati, B.; Richichi, S.J.; Ross, W.R.; Skubic, P.; Wood, M. [University of Oklahoma, Norman, Oklahoma 73019 (United States); Bishai, M.; Fast, J.; Gerndt, E.; Hinson, J.W.; Miller, D.H.; Shibata, E.I.; Shipsey, I.P.; Yurko, M. [Purdue University, West Lafayette, Indiana 47907 (United States); Gibbons, L.; Johns

1997-03-01

Using data recorded by the CLEO-II detector at CESR, we report evidence of a pair of excited charmed baryons, one decaying into {Lambda}{sup +}{sub c}{pi}{sup +} and the other into {Lambda}{sup +}{sub c}{pi}{sup -}. The doubly charged state has a measured mass difference M({Lambda}{sup +}{sub c}{pi}{sup +}) -M({Lambda}{sup +}{sub c}) of 234.5{plus_minus}1.1{plus_minus}0.8 MeV/c{sup 2} and a width of 17.9{sup +3.8}{sub -3.2}{plus_minus}4.0MeV/c{sup 2}, and the neutral state has a measured mass difference M({Lambda}{sup +}{sub c}{pi}{sup -}) -M({Lambda}{sup +}{sub c}) of 232.6{plus_minus}1.0{plus_minus}0.8 MeV/c{sup 2} and a width of 13.0{sup +3.7}{sub -3.0}{plus_minus}4.0MeV/c{sup 2}. We interpret these data as evidence of the {Sigma}{sup *++}{sub c} and {Sigma}{sup *0}{sub c}, the spin (3)/(2){sup +} excitations of the {Sigma}{sub c} baryons. {copyright} {ital 1997} {ital The American Physical Society}

Measurement of Short Living Baryon Magnetic Moment using Bent Crystals at SPS and LHC

CERN Document Server

Burmistrov, L; Ivanov, Yu; Massacrier, L; Robbe, P; Scandale, W; Stocchi, A

2016-01-01

The magnetic moments of baryons containing u,d and s quarks have been extensively studied and measured. The experimental results are all obtained by a well-assessed method that consists in measuring the polarisation vector of the incoming particles and the precession angle when the particle is travelling through an intense magnetic field. The polarization is evaluated by analysing the angular distribution of the decay products. No measurement of magnetic moments of charm or beauty baryons (and τ leptons) has been performed so far. The main reason is the lifetimes of charm/beauty baryons, too short to measure the magnetic moment by standard techniques. Historically, the prediction of baryon magnetic moments was one of the striking successes of the quark model. The importance of the measurement of heavy quark magnetic moment is to test the possibility that the charmed and/or beauty quarks has an anomalous magnetic moment, arising if those quarks are composite objects. Measurements on magnetic moments of heav...

A new look at the Y tetraquarks and Ω{sub c} baryons in the diquark model

Energy Technology Data Exchange (ETDEWEB)

Ali, Ahmed [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Maiani, Luciano [CERN, Geneva (Switzerland). Theory Div.; Borisov, Anatoly V. [Moscow State Univ. (Russian Federation). Faculty of Physics; Ahmed, Ishtiaq; Rehman, Abdur [Quaid-i-Azam Univ., Islamabad (Pakistan). National Centre for Physics; Aslam, M. Jamil [Quaid-i-Azam Univ., Islamabad (Pakistan). Department of Physics; Parkhomenko, Alexander Ya. [P.G. Demidov Yaroslavl State Univ., Yaroslavl (Russian Federation). Dept. of Theoretical Physics; Polosa, Antonio D. [Sapienza Univ. Roma (Italy). Dipt. di Fisica; INFN, Roma (Italy)

2017-08-15

We analyze the hidden charm P-wave tetraquarks in the diquark model, using an effective Hamiltonian incorporating the dominant spin-spin, spin-orbit and tensor interactions, comparing with the P-wave charmonia and with the recent analysis of the newly discovered Ω{sub c} baryons. Given the uncertain experimental situation on the Y states, we allow for two different spectra and discuss the related parameters in the diquark model, including the constrains from Ω{sub c} baryons. The diquark model allows to select a preferable Y-states pattern. The existence of higher resonances, as the one predicted with L=3, would be another footprint of the underlying diquark dynamics.

A phenomenological analysis of non-resonant charm meson decays

International Nuclear Information System (INIS)

Bediaga, I.; Goebel, C.; Mendez-Galain, R.

1997-07-01

We analyse the consequences of the usual assumption of a constant function to fit non-resonant decays from experimental Dalitz plot describing charmed meson decays. We first show, using the D + -> K 0 π + π 0 decay channel as an example, how an inadequate extraction of the non-resonant contribution could yield incorrect measurements for the resonant channels. We analyse how the correct study of this decay will provide a test for the validity of factorization in D meson decays. Finally, we show how form factors that can be measured from the D + s -> π - π + π + decay. We emphasize its relevance for the study of the decay τ -> v t 3π and the extraction of the α 1 meson width. (author)

Measurements of the Z partial decay width into c anti c and multiplicity of charm quarks per b decay

International Nuclear Information System (INIS)

Abreu, P.; Adam, W.; Adye, T.

2000-01-01

The partial decay width R c of the Z into c anti c quark pair and the number of charm quarks n c per b decay are measured with the DELPHI detector at LEP 1. Particle identification provides clear D 0 , D + , D s + and Λ c + signatures. The charm hadron production rate is measured in each channel by a fit to the scaled energy, impact parameter information and the invariant mass spectrum. Two measurements of R c are presented, from the D *+ production rate and from the overall charm counting, including strange charm baryon production, in c anti c events. The multiplicity n c , which includes hidden c anti c and strange charm baryon production, is inferred from the charm counting in b anti b events. The final results are R c =0.1665±0.0095 and n c =1.166±0.086. (orig.)

Baryons electromagnetic mass splittings in potential models

International Nuclear Information System (INIS)

Genovese, M.; Richard, J.-M.; Silvestre-Brac, B.; Varga, K.

1998-01-01

We study electromagnetic mass splittings of charmed baryons. We point out discrepancies among theoretical predictions in non-relativistic potential models; none of these predictions seems supported by experimental data. A new calculation is presented

On determination of the charmed Λc+ baryon polarization

International Nuclear Information System (INIS)

Lednitski, R.

1986-01-01

Expressions have been obtained for angular distributions in various cascade decays of the Λ c + baryon, which make it possible to evaluate its polarization and the corresponding asymmetry parameters. Errors in these parameters are estimated. An importance of polarizational measurements for the study of quark interactions at ''large'' distances is indicated. The following conclusions are made: 1.Polarization measurement of Λ c + baryon P c and measurement of asymmetry parameters of its α c decays is of importance for determination of mechanisms of quark production and hadronization. In particular, difference of asymmetries of angular distributions of decay nucleons and Λ hyperons is a measure of contribution of non-spectrum diagrams, sensitive to quark interactions at large distances. 2.Since parameters of α c asymmetry are unknown it is possible to determine only the lowe boundary corresponding to α c =1 with the help of measurement of Λ c + baryon decay asymmetries. 3.Λ c + baryon polarization and asymmetry parameters can be determined with the help of analysis of angular distributions in its cascade decays under the condition that the asymmetry parameter or other odd multipole parameter characterizing secondary decay, is known before. For measurement of Λ c + baryon polarization its two-particle or quasi-two-particle decays are mostly efficient

Meson-baryon four-body reaction amplitudes in exact SU(4)

International Nuclear Information System (INIS)

Liede, I.; Maalampi, J.; Roos, M.

1976-01-01

Fully SU(4) symmetric meson-baryon four body reaction amplitudes are presented in terms of SU(4) eigenamplitudes. The mesons and baryons considered belong to the SU(4) representations 15 and 20, respectively. Using these reletions, the cross-sections for the production of charmed particles can be predicted from known uncharmed reactions. (author)

Charm Production in Interactions of Antiproton with Proton and Nuclei at \\bar{it{P}}it{ANDA} Energies

Science.gov (United States)

Shyam, R.; Tsushima, K.

2018-05-01

We study the production of charmed baryons in the antiproton-proton and antiproton-nucleus interactions within a fully covariant model that is based on an effective Lagrangian approach. The baryon production proceeds via the t-channel D^0 and D^{*0} meson-exchange diagrams. We have also explored the production of the charm-baryon hypernucleus ^{16}_{Λ_c^+}O in the antiproton-^{16}O collisions. For antiproton beam momenta of interest to the {\\bar{P}}ANDA experiment, the 0° differential cross sections for the formation of ^{16}_{Λ_c^+}O hypernuclear states with simple particle-hole configurations, have magnitudes in the range of a few μ b/sr.

Dynamically generated resonances from the vector octet-baryon octet interaction

Energy Technology Data Exchange (ETDEWEB)

Oset, E. [Institutos de Investigacion de Paterna, Departamento de Fisica Teorica e IFIC, Centro Mixto Universidad de Valencia-CSIC, Valencia (Spain); Ramos, A. [Universitat de Barcelona, Departament d' Estructura i Constituents de la Materia and Institut de Ciencies del Cosmos, Barcelona (Spain)

2010-06-15

We study the interaction of vector mesons with the octet of stable baryons in the framework of the local hidden gauge formalism using a coupled-channels unitary approach. We examine the scattering amplitudes and their poles, which can be associated to known J{sup P}=1/2{sup -}, 3/2{sup -} baryon resonances, in some cases, or give predictions in other ones. The formalism employed produces doublets of degenerate J{sup P}= 1/2{sup -}, 3/2{sup -} states, a pattern which is observed experimentally in several cases. The findings of this work should also be useful to guide present experimental programs searching for new resonances, in particular in the strange sector where the current information is very poor. (orig.)

Charmed, beauty hadrons revisited

International Nuclear Information System (INIS)

Chabab, M.

1998-01-01

Applying two different versions of QCD sum-rules, we reanalyze rigourously the rich spectroscopy of mesons and baryons built from charm and beauty quarks. An improved determination of the masses and the leptonic decay constants of B c (bc-bar), B c *(bc-bar), and Λ(bcu) is presented. Our optimal results, constrained by stability criteria, are consistent in both versions and support the general pattern common to potential models predictions

Measurement of charmed particle production in hadronic reactions

CERN Multimedia

2002-01-01

The aim of the experiment is to measure the production cross-section for charmed particles in hadronic reactions, study their production mechanism, and search for excited charmed hadrons.\\\\ \\\\ Charmed Mesons and Baryons will be measured in $\\pi$ and $p$ interactions on Beryllium between 100 and 200 GeV/c. The trigger will be on an electron from the leptonic decay of one charmed particle by signals from the Cerenkov counter (Ce), the electron trigger calorimeter (eCal), scintillation counters, and proportional wire chambers. The accompanying charmed particle will be measured via its hadronic decay in a two-stage magnetic spectrometer with drift chambers (arms 2, 3a, 3b, 3c), two large-area multicell Cerenkov counters (C2, C3) and a large-area shower counter ($\\gamma$-CAL). The particles which can be measured and identified include $\\gamma, e, \\pi^{\\pm}, \\pi^{0}, K^{\\pm}, p, \\bar{p}$ so that a large number of hadronic decay modes of charmed particles can be studied. \\\\ \\\\ A silicon counter telescope with 5 $\\m...

Exotic baryon resonances. Modern status. Possibilities to search and investigate

International Nuclear Information System (INIS)

Bagdasaryan, L.S.; Galumyan, P.I.; Grigoryan, A.A.; Kazaryan, S.P.; Khachatryan, G.N.; Oganesyan, A.G.; Vartapetyan, H.H.

1985-01-01

A possibility to investigate the exotic baryon resonances with qqqqq quark composition, in the systems pπ + π + , Λπ - π - , Σ - π - , etc. possessing exotic quantum numbers of isospin is considered. The most favourable reactions and kinematical regions where an effective search for the exotic baryons is possible are grounded. The contribution of the background subprocesses to the investigated systems is analyzed in various reactions and momenta configurations of the particles. The analysis shows that the search for the I=5/2 resonances in the system pπ + π + (Δ ++ π + ) is more reasonable in the π + p-interaction process, this system carrying the main portion of momentum in the lab. system. The exotic hyperons with S=-1 srangeness and I=2 isospin are to be searched in the fast-flying systems Λπ - π - (Σ* - (1385)π - ) and Σ - π - produced in the reactions on the K - beams. The cross sections of the production of the E 55 -baryon (J p =5/2 + , I=5/2) in the π + p → E 55 +++ π- and π + p → E 55 +++ x processes are theoretically estimated. The estimations show that in the experiments with the OMEGA spectometer at CERN one can get a substantial increase in the statistics as compared to that available, thus providing a detailed analysis of the pπ + π + system on the high confidence level. The question of investigation of the exotic baryon Regge trajectories in the processes of the inclusive production of ordinary (nonexotic) Δ ++ (1232), Σ* + (1385)- and Σ + -resonances in the π - -beam fragmentation region is also considered

Baryon states with hidden charm in the extended local hidden gauge approach

International Nuclear Information System (INIS)

Uchino, T.; Oset, E.; Liang, Wei-Hong

2016-01-01

The s-wave interaction of anti DΛ c , anti DΣ c , anti D * Λ c , anti D * Σ c and anti DΣ c * , anti D * Σ c * , is studied within a unitary coupled channels scheme with the extended local hidden gauge approach. In addition to the Weinberg-Tomozawa term, several additional diagrams via the pion exchange are also taken into account as box potentials. Furthermore, in order to implement the full coupled channels calculation, some of the box potentials which mix the vector-baryon and pseudoscalar-baryon sectors are extended to construct the effective transition potentials. As a result, we have observed six possible states in several angular momenta. Four of them correspond to two pairs of admixture states, two of anti DΣ c - anti D * Σ c with J = 1/2, and two of anti DΣ c * - anti D * Σ c * with J = 3/2. Moreover, we find a anti D * Σ c resonance which couples to the anti DΛ c channel and one spin degenerated bound state of anti D * Σ c * with J = 1/2,5/2. (orig.)

A phenomenological analysis of non-resonant charm meson decays

Energy Technology Data Exchange (ETDEWEB)

Bediaga, I.; Goebel, C. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Mendez-Galain, R. [Montevideo Univ. (Uruguay). Facultad de Ingenieria

1997-07-01

We analyse the consequences of the usual assumption of a constant function to fit non-resonant decays from experimental Dalitz plot describing charmed meson decays. We first show, using the D{sup +} -> K{sup 0} {pi}{sup +} {pi}{sup 0} decay channel as an example, how an inadequate extraction of the non-resonant contribution could yield incorrect measurements for the resonant channels. We analyse how the correct study of this decay will provide a test for the validity of factorization in D meson decays. Finally, we show how form factors that can be measured from the D{sup +}{sub s} -> {pi}{sup -} {pi}{sup +} {pi}{sup +} decay. We emphasize its relevance for the study of the decay {tau} -> v{sub t} 3{pi} and the extraction of the {alpha}{sub 1} meson width. (author) 26 refs., 6 figs.

Measurement of the Production Cross Section for the Charmed Baryon $\\Lambda_c$ in 250 GeV/c Pion-Nucleon Interactions

Energy Technology Data Exchange (ETDEWEB)

dos Reis, Alberto Correa [Rio de Janeiro, CBPF

1992-04-01

This work a presents a measurement of the total cross section for the charmed baryon $\\Lambda_c$ times the branching fraction of the mode $\\Lambda_c \\to pK\\bar{\\mu}$, for the kinematical region $x_F$ > O in $\\pi$-nucleus interactions at 250 GeV/c. This measurement is made with data from the experiment E769, collected during 1987/1988 at the FERMILAB Tagged Photon Laboratory. A segmented target of berillium, aluminum, copper and tungsten was used. Based on the A dependence measurement, made by E769, and on the available branching fractions, the total cross section per nucleon is calculated. The result is compared with other experiments and with some theoretical predictions inspired on QCD.

Radiative open charm decay of the Y(3940), Z(3930), X(4160) resonances

International Nuclear Information System (INIS)

Liang, W.H.; Molina, R.; Oset, E.

2010-01-01

We determine the radiative decay amplitudes for the decay into D * and anti Dγ, or D * s and anti D s γ of some of the charmonium-like states classified as X, Y, Z resonances, plus some other hidden charm states which are dynamically generated from the interaction of vector mesons with charm. The mass distributions as a function of the anti Dγ or anti D s γ invariant mass show a peculiar behavior as a consequence of the D * anti D * nature of these states. The experimental search of these magnitudes can shed light on the nature of these states. (orig.)

Spectroscopy and decays of charm and bottom

International Nuclear Information System (INIS)

Butler, J.N.

1997-10-01

After a brief review of the quark model, we discuss our present knowledge of the spectroscopy of charm and bottom mesons and baryons. We go on to review the lifetimes, semileptonic, and purely leptonic decays of these particles. We conclude with a brief discussion B and D mixing and rare decays

Pion-nucleon scattering in covariant baryon chiral perturbation theory with explicit Delta resonances

Energy Technology Data Exchange (ETDEWEB)

Yao, De-Liang [Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); Siemens, D. [Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Bernard, V. [Groupe de Physique Théorique, Institut de Physique Nucléaire, UMR 8606,CNRS, University Paris-Sud, Université Paris-Saclay, 91405 Orsay Cedex (France); Epelbaum, E. [Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Gasparyan, A.M. [Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44780 Bochum (Germany); SSC RF ITEP, Bolshaya Cheremushkinskaya 25, 117218 Moscow (Russian Federation); Gegelia, J. [Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany); Tbilisi State University, 0186 Tbilisi (Georgia); Krebs, H. [Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Meißner, Ulf-G. [Helmholtz Institut für Strahlen- und Kernphysik andBethe Center for Theoretical Physics, Universität Bonn, D-53115 Bonn (Germany); Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron Physics,Forschungszentrum Jülich, D-52425 Jülich (Germany)

2016-05-05

We present the results of a third order calculation of the pion-nucleon scattering amplitude in a chiral effective field theory with pions, nucleons and delta resonances as explicit degrees of freedom. We work in a manifestly Lorentz invariant formulation of baryon chiral perturbation theory using dimensional regularization and the extended on-mass-shell renormalization scheme. In the delta resonance sector, the on mass-shell renormalization is realized as a complex-mass scheme. By fitting the low-energy constants of the effective Lagrangian to the S- and P-partial waves a satisfactory description of the phase shifts from the analysis of the Roy-Steiner equations is obtained. We predict the phase shifts for the D and F waves and compare them with the results of the analysis of the George Washington University group. The threshold parameters are calculated both in the delta-less and delta-full cases. Based on the determined low-energy constants, we discuss the pion-nucleon sigma term. Additionally, in order to determine the strangeness content of the nucleon, we calculate the octet baryon masses in the presence of decuplet resonances up to next-to-next-to-leading order in SU(3) baryon chiral perturbation theory. The octet baryon sigma terms are predicted as a byproduct of this calculation.

Masses and Regge trajectories of triply heavy Ω{sub ccc} and Ω{sub bbb} baryons

Energy Technology Data Exchange (ETDEWEB)

Shah, Zalak; Rai, Ajay Kumar [Sardar Vallabhbhai National Institute of Technology, Department of Applied Physics, Surat, Gujarat (India)

2017-10-15

The excited state masses of triply charm and triply bottom Ω baryons are exhibited in the present study. The masses are computed for 1S-5S, 1P-5P, 1D-4D and 1F-2F states in the Hypercentral Constituent Quark Model (hCQM) with the hyper Coulomb plus linear potential. The triply charm/bottom baryon masses are experimentally unknown so that the Regge trajectories are plotted using computed masses to assign the quantum numbers of these unknown states. (orig.)

Magnetic moments of the lowest-lying singly heavy baryons

Science.gov (United States)

Yang, Ghil-Seok; Kim, Hyun-Chul

2018-06-01

A light baryon is viewed as Nc valence quarks bound by meson mean fields in the large Nc limit. In much the same way a singly heavy baryon is regarded as Nc - 1 valence quarks bound by the same mean fields, which makes it possible to use the properties of light baryons to investigate those of the heavy baryons. A heavy quark being regarded as a static color source in the limit of the infinitely heavy quark mass, the magnetic moments of the heavy baryon are determined entirely by the chiral soliton consisting of a light-quark pair. The magnetic moments of the baryon sextet are obtained by using the parameters fixed in the light-baryon sector. In this mean-field approach, the numerical results of the magnetic moments of the baryon sextet with spin 3/2 are just 3/2 larger than those with spin 1/2. The magnetic moments of the bottom baryons are the same as those of the corresponding charmed baryons.

Electro- and chromomagnetism in the charm meson spectrum

International Nuclear Information System (INIS)

Fritzsch, H.

1977-01-01

How the D and F meson spectrum is influenced by the chromomagnetic and electomagnetic hyperfine interaction is discussed. In particular a relation between the hyperfine splitting of charmed mesons and the magnetic moments of the baryons is derived. M(Fsub(+)*)-M(Fsub(+)) approximately 100+-8 MeV. (Auth.)

Weak form factors of beauty baryons

International Nuclear Information System (INIS)

Ivanov, M.A.; Lyubovitskij, V.E.

1992-01-01

Full analysis of semileptonic decays of beauty baryons with J p =1/2 2 and J p =3/2 2 into charmed ones within the Quark Confinement Model is reported. Weak form factors and decay rates are calculated. Also the heavy quark limit m Q →∞ (Isgur-Wise symmetry) is examined. The weak heavy-baryon form factors in the Isgur-Wise limit and 1/m Q -corrections to them are computered. The Ademollo-Gatto theorem is spin-flavour symmetry of heavy quarks is checked. 33 refs.; 1 fig.; 9 tabs

Heavy flavor baryons in hypercentral model

International Nuclear Information System (INIS)

Patel, Bhavin; Vinodkumar, P.C.; Rai, Ajay Kumar

2008-01-01

Heavy flavor baryons containing single and double charm (beauty) quarks with light flavor combinations are studied using the hypercentral description of the three- body problem. The confinement potential is assumed as hypercentral Coulomb plus power potential with power index υ. The ground state masses of the heavy flavor, J P = 1/2 + and 3/2 + baryons are computed for different power indices, υ starting from 0.5 to 2.0. The predicted masses are found to attain a saturated value in each case of quark combinations beyond the power index υ = 1.0. (author)

Resonant scattering and charm showers in ultrahigh-energy neutrino interactions

Science.gov (United States)

Wilczek, F.

1985-01-01

Electron antineutrinos with energy of about 7 x 10 to the 6th GeV have much-enhanced cross sections due to W-boson production off electrons. Possible signals due to cosmic-ray sources are estimated. Higher-energy antineutrinos can efficiently produce a W accompanied by radiation. Another possibility, which could lead to shadowing at modest depths, is resonant production of a charged Higgs particle. The importance of muon production by charm showers in rock is pointed out.

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...

Analysis of the photocouplings of baryon resonances

Energy Technology Data Exchange (ETDEWEB)

Bando, M; Toya, M [Kyoto Univ. (Japan). Dept. of Physics; Sugimoto, Hiroshi

1978-02-01

The typical features of the photocouplings of the 70 L=1 and 56 L=2 baryon resonances are discussed in view of the recently reported experimental data. It is emphasized that our relativistic quark model is very convenient for the phenomenological study on the photocouplings and also is suitable for a simple physical interpretation. The phenomenological analysis of the photocoupling data based on our model concludes that the transition from the quark state (jsup(P)=1/2/sup +/, lambda=1/2) to (j=L + 1/2, lambda=3/2) is dominant in the photo-transitions from nucleons to the excited baryons in both cases L=1 and 2. Our result implies the non-negligible magnitude of the value of delta L sub(z)=2 term. The experimental data on A sub(1/2)sup(p)(P/sub 13/) and A sub(3/2)sup(p)(P/sub 13/) is crucial to confirm the strength of delta L sub(z)=2 term.

Baryon structure

International Nuclear Information System (INIS)

Morsch, H.P.; Forschungszentrum Juelich GmbH

1993-01-01

A brief review on the theoretical and experimental situation of baryon spectroscopy is first given. Then, the radial structure of baryons, related to the ground state form factors and the baryonic compressibility, is discussed. An experiment has been performed at Saturne laboratory (France) in which for the first time a compression of the nucleon is observed, exciting the P 11 (1440 MeV) resonance (Roper resonance) by α-particles. The analysis of the data indicates that this excitation covers a large fraction of the available monopole strength in the nucleon. The derived compressibility is discussed as well as the consequence for other fields, as nuclear medium effects on baryon properties, high density phenomena in nuclear collisions as well as colour transparency. In the last point the spin-flip structure of the P 11 (1440 MeV) resonance is discussed. The possibility to determine isoscalar spin-flip strength by polarized deuteron scattering is contrasted with first preliminary results from photon-induced reactions studied at Mainz which indicate a non-negligible M1 excitation of the Roper resonance. (author) 10 figs., 31 refs

Baryon states with hidden charm in the extended local hidden gauge approach

Energy Technology Data Exchange (ETDEWEB)

Uchino, T.; Oset, E. [Centro Mixto Universidad de Valencia-CSIC, Institutos de Investigacion de Paterna, Departamento de Fisica Teorica y IFIC, Valencia (Spain); Liang, Wei-Hong [Guangxi Normal University, Department of Physics, Guilin (China)

2016-03-15

The s-wave interaction of anti DΛ{sub c}, anti DΣ{sub c}, anti D{sup *}Λ{sub c}, anti D{sup *}Σ{sub c} and anti DΣ{sub c}{sup *}, anti D{sup *}Σ{sub c}{sup *}, is studied within a unitary coupled channels scheme with the extended local hidden gauge approach. In addition to the Weinberg-Tomozawa term, several additional diagrams via the pion exchange are also taken into account as box potentials. Furthermore, in order to implement the full coupled channels calculation, some of the box potentials which mix the vector-baryon and pseudoscalar-baryon sectors are extended to construct the effective transition potentials. As a result, we have observed six possible states in several angular momenta. Four of them correspond to two pairs of admixture states, two of anti DΣ{sub c} - anti D{sup *}Σ{sub c} with J = 1/2, and two of anti DΣ{sub c}{sup *} - anti D{sup *}Σ{sub c}{sup *} with J = 3/2. Moreover, we find a anti D{sup *}Σ{sub c} resonance which couples to the anti DΛ{sub c} channel and one spin degenerated bound state of anti D{sup *}Σ{sub c}{sup *} with J = 1/2,5/2. (orig.)

Search for Baryonic Resonances Decaying to $\\Xi \\pi$ in Deep-Inelastic Scattering at HERA

CERN Document Server

Aktas, A.; Andreev, V.; Anthonis, T.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Backovic, S.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Beckingham, M.; Begzsuren, K.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, N.; Bizot, J.C.; Boenig, M.-O.; Boudry, V.; Bozovic-Jelisavcic, I.; Bracinik, J.; Brandt, G.; Brinkmann, M.; Brisson, V.; Bruncko, D.; Busser, F.W.; 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.; De Roeck, A.; De Wolf, E.A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, Guenter; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eliseev, A.; Elsen, E.; Essenov, S.; Falkewicz, A.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Finke, L.; Fleischer, M.; Fomenko, A.; Franke, G.; Frisson, T.; Gabathuler, E.; Garutti, E.; Gayler, J.; Ghazaryan, Samvel; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Gouzevitch, M.; Grab, C.; Greenshaw, T.; Grell, B.R.; Grindhammer, G.; Habib, S.; Haidt, D.; Hansson, M.; Heinzelmann, G.; Helebrant, C.; Henderson, R.C.W.; Henschel, H.; Herrera, G.; Hildebrandt, M.; Hiller, K.H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Hreus, T.; Jacquet, M.; Janssen, M.E.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, D.P.; Jung, Andreas Werner; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I.R.; Kiesling, Christian M.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knutsson, A.; Korbel, V.; Kostka, P.; Kraemer, M.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Kruger, K.; Landon, M.P.J.; Lange, W.; Lastovicka-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.-I.; Lytkin, L.; Makankine, A.; Malinovski, E.; Marage, P.; Marti, Ll.; Martisikova, M.; Martyn, H.-U.; Maxfield, S.J.; Mehta, A.; Meier, K.; Meyer, A.B.; Meyer, H.; Meyer, J.; Michels, V.; Mikocki, S.; Milcewicz-Mika, I.; Mladenov, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J.V.; Mozer, Matthias Ulrich; Muller, K.; Murin, P.; Nankov, K.; Naroska, B.; Naumann, Th.; Newman, Paul R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J.E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Pandurovic, M.; Papadopoulou, Th.; Pascaud, C.; Patel, G.D.; Peng, H.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Picuric, I.; Piec, S.; Pitzl, D.; Placakyte, R.; Povh, B.; Preda, T.; Prideaux, P.; Rahmat, A.J.; Raicevic, N.; Ravdandorj, T.; Reimer, P.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D.P.C.; Sauter, M.; Sauvan, E.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schoning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shaw-West, R.N.; Sheviakov, I.; Shtarkov, L.N.; Sloan, T.; Smiljanic, Ivan; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, Arnd E.; Staykova, Z.; Steder, M.; Stella, B.; Stiewe, J.; Straumann, U.; Sunar, D.; Sykora, T.; Tchoulakov, V.; Thompson, G.; Thompson, P.D.; Toll, T.; Tomasz, F.; Traynor, D.; Trinh, T.N.; Truol, P.; Tsakov, I.; Tseepeldorj, B.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, K.; Utkin, D.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Vinokurova, S.; Volchinski, V.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Wessels, M.; Wissing, Ch.; Wolf, R.; Wunsch, E.; Xella, S.; Yeganov, V.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zhu, Y.C.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.

2007-01-01

A search for narrow baryonic resonances decaying into Xi- pi- or Xi- pi+ and their antiparticles is carried out with the H1 detector using deep inelastic scattering events at HERA in the range of negative photon four-momentum transfer squared 2 < Q^2 < 100 GeV^2. No signal is observed for a new baryonic state in the mass range 1600 - 2300 MeV in either the doubly charged or the neutral decay channels. The known baryon Xi0 is observed through its decay mode into Xi- pi+. Upper limits are given on the ratio of the production rates of new baryonic states, such as the hypothetical pentaquark states Xi^{--}_{5q} or Xi^{0}_{5q}, relative to the Xi0 baryon state.

Baryon resonance production and dielectron decays in proton-proton collisions at 3.5 GeV

Energy Technology Data Exchange (ETDEWEB)

Agakishiev, G.; Belyaev, A.; Chernenko, S.; Fateev, O.; Ierusalimov, A.; Ladygin, V.; Vasiliev, T.; Zanevsky, Y. [Joint Institute of Nuclear Research, Dubna (Russian Federation); Balanda, A.; Dybczak, A.; Michalska, B.; Palka, M.; Przygoda, W.; Salabura, P.; Trebacz, R. [Jagiellonian University of Cracow, Smoluchowski Institute of Physics, Krakow (Poland); Belver, D.; Cabanelas, P.; Garzon, J.A. [Univ. de Santiago de Compostela, LabCAF. F. Fisica, Santiago de Compostela (Spain); Berger-Chen, J.C.; Epple, E.; Fabbietti, L.; Lalik, R.; Lapidus, K.; Siebenson, J. [Excellence Cluster ' ' Origin and Structure of the Universe' ' , Garching (Germany); Blanco, A.; Fonte, P.; Lopes, L.; Mangiarotti, A. [LIP-Laboratorio de Instrumentacao e Fisica Experimental de Particulas, Coimbra (Portugal); Boehmer, M.; Friese, J.; Gernhaeuser, R.; Jurkovic, M.; Kruecken, R.; Maier, L.; Weber, M. [Technische Universitaet Muenchen, Physik Department E12, Garching (Germany); Boyard, J.L.; Hennino, T.; Liu, T.; Ramstein, B. [Universite Paris Sud, Institut de Physique Nucleaire (UMR 8608), CNRS/IN2P3, Orsay Cedex (France); Finocchiaro, P.; Schmah, A.; Spataro, S. [Laboratori Nazionali del Sud, INFN, Catania (Italy); Froehlich, I.; Goebel, K.; Lorenz, M.; Markert, J.; Michel, J.; Muentz, C.; Pachmayer, Y.C.; Pechenova, O.; Rustamov, A.; Stroebele, H.; Tarantola, A.; Teilab, K. [Goethe-Universitaet, Institut fuer Kernphysik, Frankfurt (Germany); Galatyuk, T.; Gonzalez-Diaz, D.; Gumberidze, M.; Kornakov, G. [Technische Universitaet Darmstadt, Darmstadt (Germany); Golubeva, M.; Guber, F.; Ivashkin, A.; Karavicheva, T.; Kurepin, A.; Reshetin, A.; Sadovsky, A. [Russian Academy of Science, Institute for Nuclear Research, Moscow (Russian Federation); Heinz, T.; Holzmann, R.; Koenig, I.; Koenig, W.; Kolb, B.W.; Lang, S.; Pechenov, V.; Pietraszko, J.; Schwab, E.; Sturm, C.; Traxler, M.; Yurevich, S. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Iori, I. [Sezione di Milano, INFN, Milano (Italy); Kaempfer, B.; Kotte, R.; Naumann, L.; Wendisch, C.; Wuestenfeld, J. [Institut fuer Strahlenphysik, Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany); Krasa, A.; Krizek, F.; Kugler, A.; Sobolev, Yu.G.; Tlusty, P.; Wagner, V. [Academy of Sciences of Czech Republic, Nuclear Physics Institute, Rez (Czech Republic); Kuc, H. [Jagiellonian University of Cracow, Smoluchowski Institute of Physics, Krakow (Poland); Universite Paris Sud, Institut de Physique Nucleaire (UMR 8608), CNRS/IN2P3, Orsay Cedex (France); Kuehn, W.; Metag, V.; Spruck, B. [Justus Liebig Universitaet Giessen, II.Physikalisches Institut, Giessen (Germany); Lebedev, A. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Parpottas, Y.; Tsertos, H. [University of Cyprus, Department of Physics, Nicosia (Cyprus); Stroth, J. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Goethe-Universitaet, Institut fuer Kernphysik, Frankfurt (Germany)

2014-05-15

We report on baryon resonance production and decay in proton-proton collisions at a kinetic energy of 3.5 GeV based on data measured with HADES. The exclusive channels pp → npπ{sup +} and pp → ppπ{sup 0} as well as pp → ppe{sup +}e{sup -} are studied simultaneously for the first time. The invariant masses and angular distributions of the pion-nucleon systems were studied and compared to simulations based on a resonance model ansatz assuming saturation of the pion production by an incoherent sum of baryonic resonances (R) with masses < 2 GeV/c{sup 2}. A very good description of the one-pion production is achieved allowing for an estimate of individual baryon resonance production cross sections which are used as input to calculate the dielectron yields from R → pe{sup +}e{sup -} decays. Two models of the resonance decays into dielectrons are examined assuming a point-like RNγ{sup *} coupling and the dominance of the ρ meson. The results of model calculations are compared to data from the exclusive ppe{sup +}e{sup -} channel by means of the dielectron and pe{sup +}e{sup -} invariant mass distributions. (orig.)

QCD sum rule study of hidden-charm pentaquarks

Energy Technology Data Exchange (ETDEWEB)

Chen, Hua-Xing; Cui, Er-Liang [Beihang University, School of Physics and Beijing Key Laboratory of Advanced Nuclear Materials and Physics, Beijing (China); Chen, Wei; Steele, T.G. [University of Saskatchewan, Department of Physics and Engineering Physics, Saskatoon, Saskatchewan (Canada); Liu, Xiang [Lanzhou University, School of Physical Science and Technology, Lanzhou (China); Lanzhou University and Institute of Modern Physics of CAS, Research Center for Hadron and CSR Physics, Lanzhou (China); Zhu, Shi-Lin [Peking University, School of Physics and State Key Laboratory of Nuclear Physics and Technology, Beijing (China); Collaborative Innovation Center of Quantum Matter, Beijing (China); Peking University, Center of High Energy Physics, Beijing (China)

2016-10-15

We study the mass spectra of hidden-charm pentaquarks having spin J = (1)/(2)/(3)/(2)/(5)/(2) and quark contents uudc anti c. We systematically construct all the relevant local hidden-charm pentaquark currents, and we select some of them to perform QCD sum rule analyses. We find that the P{sub c}(4380) and P{sub c}(4450) can be identified as hidden-charm pentaquark states composed of an anti-charmed meson and a charmed baryon. Besides them, we also find (a) the lowest-lying hidden-charm pentaquark state of J{sup P} = 1/2{sup -} has the mass 4.33{sup +0.17}{sub -0.13} GeV, while the one of J{sup P} = 1/2{sup +} is significantly higher, that is, around 4.7-4.9 GeV; (b) the lowest-lying hidden-charm pentaquark state of J{sup P} = 3/2{sup -} has the mass 4.37{sup +0.18}{sub -0.13} GeV, consistent with the P{sub c}(4380) of J{sup P} = 3/2{sup -}, while the one of J{sup P} = 3/2{sup +} is also significantly higher, that is, above 4.6 GeV; (c) the hidden-charm pentaquark state of J{sup P} = 5/2{sup -} has a mass around 4.5-4.6 GeV, slightly larger than the P{sub c}(4450) of J{sup P} = 5/2{sup +}. (orig.)

Resonances in QCD

Energy Technology Data Exchange (ETDEWEB)

Lutz, Matthias F.M., E-mail: m.lutz@gsi.de [GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt (Germany); Technische Universität Darmstadt, D-64289 Darmstadt (Germany); Lange, Jens Sören, E-mail: Soeren.Lange@exp2.physik.uni-giessen.de [II. Physikalisches Institut, Justus-Liebig-Universität Giessen, D-35392 Giessen (Germany); Pennington, Michael, E-mail: michaelp@jlab.org [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Bettoni, Diego [Istituto Nazionale di Fisica Nucleare, Sezione di Ferrara, 44122 Ferrara (Italy); Brambilla, Nora [Physik Department, Technische Universität München, D-85747 Garching (Germany); Crede, Volker [Department of Physics, Florida State University, Tallahassee, FL 32306 (United States); Eidelman, Simon [Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Budker Istitute of Nuclear Physics SB RAS, Novosibirsk 630090 (Russian Federation); Gillitzer, Albrecht [Institut für Kernphysik, Forschungszentrum Jülich GmbH, D-52425 Jülich (Germany); Gradl, Wolfgang [Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55128 Mainz (Germany); Lang, Christian B. [Institut für Physik, Universität Graz, A-8010 Graz (Austria); Metag, Volker [II. Physikalisches Institut, Justus-Liebig-Universität Giessen, D-35392 Giessen (Germany); Nakano, Takashi [Research Center for Nuclear Physics, Osaka University, Osaka 567-0047 (Japan); and others

2016-04-15

We report on the EMMI Rapid Reaction Task Force meeting ‘Resonances in QCD’, which took place at GSI October 12–14, 2015. A group of 26 people met to discuss the physics of resonances in QCD. The aim of the meeting was defined by the following three key questions: • What is needed to understand the physics of resonances in QCD? • Where does QCD lead us to expect resonances with exotic quantum numbers? • What experimental efforts are required to arrive at a coherent picture? For light mesons and baryons only those with up, down and strange quark content were considered. For heavy–light and heavy–heavy meson systems, those with charm quarks were the focus. This document summarizes the discussions by the participants, which in turn led to the coherent conclusions we present here.

Resonances in QCD

Energy Technology Data Exchange (ETDEWEB)

Lutz, Matthias F. M.; Lange, Jens Sören; Pennington, Michael; Bettoni, Diego; Brambilla, Nora; Crede, Volker; Eidelman, Simon; Gillitzer, Albrecht; Gradl, Wolfgang; Lang, Christian B.; Metag, Volker; Nakano, Takashi; Nieves, Juan; Neubert, Sebastian; Oka, Makoto; Olsen, Stephen L.; Pappagallo, Marco; Paul, Stephan; Pelizäus, Marc; Pilloni, Alessandro; Prencipe, Elisabetta; Ritman, Jim; Ryan, Sinead; Thoma, Ulrike; Uwer, Ulrich; Weise, Wolfram

2016-04-01

We report on the EMMI Rapid Reaction Task Force meeting 'Resonances in QCD', which took place at GSI October 12-14, 2015 (Fig.~1). A group of 26 people met to discuss the physics of resonances in QCD. The aim of the meeting was defined by the following three key questions; what is needed to understand the physics of resonances in QCD?; where does QCD lead us to expect resonances with exotic quantum numbers?; and what experimental efforts are required to arrive at a coherent picture? For light mesons and baryons only those with up, down and strange quark content were considered. For heavy-light and heavy-heavy meson systems, those with charm quarks were the focus.This document summarizes the discussions by the participants, which in turn led to the coherent conclusions we present here.

Study of charmed baryon Λ+sub(c) associated with an electron release in proton-proton collisions at √s = 63 GeV

International Nuclear Information System (INIS)

Sajot, G.

1980-01-01

The production of the charmed baryon Λ + sub(c) in proton-proton collisions at 63 GeV is studied. The experiment was performed at the C.E.R.N. - I.S.R. on the S.F.M. The event is recorded if an electron is recognized, this electron coming from the semi-leptonic decay of the anticharmed particle accompanying the Λ + sub(c). The total cross section for the production of the pair anticharmed particle Λ + sub(c) is estimated by several models. By comparison with others experiments producing Λ + sub(c) at the I.S.R., one deduces that the model d sigma/dy = cte best agrees with the experimental data [fr

Discovery of charm

International Nuclear Information System (INIS)

Goldhaber, G.

1984-11-01

In my talk I will cover the period 1973 to 1976 which saw the discoveries of the J/psi and psi' resonances and most of the Psion spectroscopy, the tau lepton and the D 0 ,D + charmed meson doublet. Occasionally I will refer briefly to more recent results. Since this conference is on the history of the weak-interactions I will deal primarily with the properties of naked charm and in particular the weakly decaying doublet of charmed mesons. Most of the discoveries I will mention were made with the SLAC-LBL Magnetic Detector or MARK I which we operated at SPEAR from 1973 to 1976. 27 references

Weak decays of doubly heavy baryons. The 1/2 → 1/2 case

Energy Technology Data Exchange (ETDEWEB)

Wang, Wei; Zhao, Zhen-Xing [Shanghai Jiao Tong University, INPAC, Shanghai Key Laboratory for Particle Physics and Cosmology, School of Physics and Astronomy, Shanghai (China); Yu, Fu-Sheng [Lanzhou University, School of Nuclear Science and Technology, Lanzhou (China)

2017-11-15

Very recently, the LHCb collaboration has observed in the final state Λ{sub c}{sup +}K{sup -}π{sup +}π{sup +} a resonant structure that is identified as the doubly charmed baryon Ξ{sub cc}{sup ++}. Inspired by this observation, we investigate the weak decays of doubly heavy baryons Ξ{sub cc}{sup ++}, Ξ{sub cc}{sup +}, Ω{sub cc}{sup +}, Ξ{sub bc}{sup (')+}, Ξ{sub bc}{sup (')0}, Ω{sub bc}{sup (')0}, Ξ{sub bb}{sup 0}, Ξ{sub bb}{sup -} and Ω{sub bb}{sup -} and focus on the decays into spin 1/2 baryons in this paper. At the quark level these decay processes are induced by the c → d/s or b → u/c transitions, and the two spectator quarks can be viewed as a scalar or axial vector diquark. We first derive the hadronic form factors for these transitions in the light-front approach and then apply them to predict the partial widths for the semileptonic and nonleptonic decays of doubly heavy baryons. We find that the number of decay channels is sizable and can be examined in future measurements at experimental facilities like LHC, Belle II and CEPC. (orig.)

New results on CLEO's heavy quarks - bottom and charm

International Nuclear Information System (INIS)

Menary, S.

1997-01-01

While the top quark is confined to virtual reality for CLEO, the increased luminosity of the Cornell Electron Storage Ring (CESR) and the improved photon detection capabilities of the CLEO's open-quotes heavyclose quotes quarks - bottom and charm. I will describe new results in the B meson sector including the first observation of exclusive b → ulv decays, upper limits on gluonic penguin decay rates, and precise measurements of semileptonic and hadronic b → c branching fractions. The charmed hadron results that are discussed include the observation of isospin violation in D s * + decays, an update on measurements of the D s + decay constant, and the observation of a new excited Ξ c charmed baryon. These measurements have had a large impact on our understanding of heavy quark physics

Search for semileptonic decays of photoproduced charmed mesons

International Nuclear Information System (INIS)

Coleman, R.N.

1977-01-01

In the broad band neutral beam at Fermilab, a search for photoproduction of charmed D mesons was done using photons of 100 to 300 GeV. The reaction considered was γ + Be → DantiD + X, leptons + ..., K 0 /sub s/nπ/sup +-/. No statistically significant evidence for D production is observed based on the K 0 /sub s/nπ/sup +-/ mass spectrum. The sensitivity of the search is commensurate with theoretical estimates of sigma(γp → DantiD + X) approximately 500 nb, however this is dependent on branching ratios and photoproduction models. Data are given on a similar search for semileptonic decays of charmed baryons. 48 references

Magnetic moments of the spin-(3)/(2) doubly heavy baryons

Energy Technology Data Exchange (ETDEWEB)

Meng, Lu; Li, Hao-Song [Peking University, School of Physics and State Key Laboratory of Nuclear Physics and Technology, Beijing (China); Liu, Zhan-Wei [Lanzhou University, School of Physical Science and Technology, Lanzhou (China); Zhu, Shi-Lin [Peking University, School of Physics and State Key Laboratory of Nuclear Physics and Technology, Beijing (China); Collaborative Innovation Center of Quantum Matter, Beijing (China)

2017-12-15

In this work, we investigate the chiral corrections to the magnetic moments of the spin-(3)/(2) doubly charmed baryons systematically up to next-to-next-to-leading order with the heavy baryon chiral perturbation theory. The numerical results are given up to next-to-leading order: μ{sub Ξ}{sup {sub *}{sub +}{sub +{sub c{sub c}}}} = 2.61μ{sub N}, μ{sub Ξ}{sup {sub *}{sub +{sub c{sub c}}}} = -0.18μ{sub N}, μ{sub Ω}{sup {sub *}{sub +{sub c{sub c}}}} = 0.17μ{sub N}. As a by-product, we have also calculated the magnetic moments of the spin-(3)/(2) doubly bottom baryons and charmed bottom baryons: μ{sub Ξ}{sup {sub *}{sub 0{sub b{sub b}}}} = 2.83μ{sub N}, μ{sub Ξ}{sup {sub *}{sub -{sub b{sub b}}}} = -1.33μ{sub N}, μ{sub Ω}{sup {sub *}{sub -{sub b{sub b}}}} = -1.54μ{sub N}, μ{sub Ξ}{sup {sub *}{sub +{sub b{sub c}}}} = 3.22μ{sub N}, μ{sub Ξ}{sup {sub *}{sub 0{sub b{sub c}}}} = -0.84μ{sub N}, μ{sub Ω}{sup {sub *}{sub 0{sub b{sub c}}}} = -1.09μ{sub N}. (orig.)

Electro- and chromomagnetism in the charm meson spectrum

CERN Document Server

Fritzsch, Harald

1977-01-01

How the D and F meson spectrum is influenced by the chromomagnetic and electromagnetic hyperfine interaction is discussed. In particular a relation between the hyperfine splitting of charmed mesons and the magnetic moments of the baryons is derived. It is found that M(F/sub + /*)-M(F/sub +/) approximately=100+or-8 MeV. (12 refs).

Fermilab experiment E-687: Recent results on charm

International Nuclear Information System (INIS)

Shephard, W.D.

1990-12-01

About 10 4 charm decays have been reconstructed from first-run data of Fermilab experiment E687 using the Fermilab Wide-Band Photon Spectrometer with the world's highest energy photon beam. Charm selection strategies and preliminary results are discussed. Lifetime values are (.50 ± .06 ± .03)ps for the D s + and (.20 ± .03 ± .03)ps for the Λ c + . Preliminary D + and D 0 lifetimes are consistent with current world averages. Signals for charm baryon and Cabibbo-suppressed charm meson decays are shown. Preliminary branching ratios are: B(D 0 → π + π - π + π - )/B(D 0 → K - π + π + π - ) = .10 ± .02 ± .02; B(D 0 → bar K 0 K + K - )/B(D 0 → bar K 0 π + π - ) = .20 ± .06(stat); B(D 0 → bar K 0 φ)/B(D 0 → bar K 0 π + π - ) = .16 ± .06(stat). Preliminary results are given on D* ± and D ±,0 photoproduction for photon energies from 100 to 350 GeV. 13 refs., 3 figs

Calculation of hadronic transition amplitudes in charm physics; Berechnung hadronischer Uebergangsamplituden in der Charm-Physik

Energy Technology Data Exchange (ETDEWEB)

Klein, Christoph

2011-09-23

Transitions of charmed hadrons are of significant importance, since they provide possibilities to extract the CKM matrix elements V{sub cd} and V{sub cs} from experimental data as well as interesting channels to search for new physics effects. However, quarks are bound in hadrons, and it is necessary to describe this effect in a reliable way, to study the underlying flavour dynamics. For this, one has to use nonperturbative tools, to determine the corresponding transition amplitudes. The results of such calculations can furthermore be of use, to test the predictions of QCD and to contribute to a deeper understanding of the structure of hadrons. In this thesis two topics are investigated using the method of QCD light-cone sum rules (LCSRs). The first topic consists in the form factors of the semileptonic decays D {yields} {pi}l{nu}{sub l} and D {yields} Kl{nu}{sub l}, for which new results are calculated using up-to-date input values. Since LCSRs are not applicable in the whole range of kinematics, they are extrapolated by the use of appropriate parametrisations and the results agree well with experimental data. The second topic are the transitions of charmed baryons to a nucleon. Here the corresponding transition form factors and in addition the hadronic {lambda}{sub c}D{sup (*)}N and {sigma}{sub c}D{sup (*)}N coupling constants are calculated - the latter by the consideration of double dispersion relations. These coupling constants are of special interest for the description of hadronic interactions, like open charm production in proton-antiprotoncollisions. Furthermore there appears the problem, that both parity states of a baryon contribute to the considered functional representation, for which a consistent way to separate them is presented. (orig.)

Fragmentation production of Ωccc baryons at LHC energies

International Nuclear Information System (INIS)

Saleev, V.A.

2000-01-01

Within the nonrelativistic quark-diquark model for heavy baryons, the fragmentation functions for the transitions of a c-quark and a doubly charmed vector diquark into an Ω ccc baryon are calculated in the leading order of perturbative QCD. The cross section for Ω ccc production in high-energy hadron interactions is estimated. It is assumed that Ω ccc baryons are formed via the fragmentation of a c quark or a vector (cc) diquark produced in the partonic subprocesses gg → cc-bar, qq-bar → cc-bar, gg → (cc) + c-bar + c-bar, and qq-bar → (cc) + c-bar + c-bar

Exotic heavy baryons at LHC

International Nuclear Information System (INIS)

Biro, T.S.; Zimanyi, J.

1993-06-01

A heavy bottom-charm six-quark baryon is considered. A semiclassical and a Gaussian estimate show that the octet-octet bbb-ccc configuration can be favoured energetically rather than the singlet-singlet one. This result suggests that a confined bbb-ccc six-quark state may exist. Such objects may be produced in suitable amounts by heavy-ion collisions at Large Hadronic Collider energies. (R.P.) 8 refs. 1 fig

Search for baryonic resonances decaying to Ξπ in deep-inelastic scattering at HERA

Science.gov (United States)

Aktas, A.; Alexa, C.; Andreev, V.; Anthonis, T.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Backovic, S.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Beckingham, M.; Begzsuren, K.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, N.; Bizot, J. C.; Boenig, M.-O.; Boudry, V.; Bozovic-Jelisavcic, I.; Bracinik, J.; Brandt, G.; Brinkmann, M.; Brisson, V.; Bruncko, D.; Büsser, F. W.; 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.; de Roeck, A.; de Wolf, E. A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eliseev, A.; Elsen, E.; Essenov, S.; Falkewicz, A.; Faulkner, P. J. W.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Finke, L.; Fleischer, M.; Fomenko, A.; Franke, G.; Frisson, T.; Gabathuler, E.; Garutti, E.; Gayler, J.; Ghazaryan, S.; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Gouzevitch, M.; Grab, C.; Greenshaw, T.; Grell, B. R.; Grindhammer, G.; Habib, S.; Haidt, D.; Hansson, M.; Heinzelmann, G.; Helebrant, C.; Henderson, R. C. W.; Henschel, H.; Herrera, G.; Hildebrandt, M.; Hiller, K. H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Hreus, T.; Jacquet, M.; Janssen, M. E.; Janssen, X.; Jemanov, V.; Jönsson, L.; Johnson, D. P.; Jung, A. W.; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I. R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knutsson, A.; Korbel, V.; Kostka, P.; Kraemer, M.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Krüger, K.; Landon, M. P. J.; Lange, W.; Laštovička-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.-I.; Lytkin, L.; Makankine, A.; Malinovski, E.; Marage, P.; Marti, L.; Martisikova, M.; 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.; Mladenov, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J. V.; Mozer, M. U.; Müller, K.; Murín, P.; Nankov, K.; Naroska, B.; Naumann, T.; Newman, P. R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J. E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Pandurovic, M.; Papadopoulou, T.; Pascaud, C.; Patel, G. D.; Peng, H.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Picuric, I.; Piec, S.; Pitzl, D.; Plačakytė, R.; Povh, B.; Preda, T.; Prideaux, P.; Rahmat, A. J.; Raicevic, N.; Ravdandorj, T.; Reimer, P.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D. P. C.; Sauter, M.; Sauvan, E.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schöning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shaw-West, R. N.; Sheviakov, I.; Shtarkov, L. N.; Sloan, T.; Smiljanic, I.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, A.; Staykova, Z.; Steder, M.; Stella, B.; Stiewe, J.; Straumann, U.; Sunar, D.; Sykora, T.; Tchoulakov, V.; Thompson, G.; Thompson, P. D.; Toll, T.; Tomasz, F.; Traynor, D.; Trinh, T. N.; Truöl, P.; Tsakov, I.; Tseepeldorj, B.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, K.; Utkin, D.; Valkárová, A.; Vallée, C.; van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Vinokurova, S.; Volchinski, V.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Wessels, M.; Wissing, C.; Wolf, R.; Wünsch, E.; Xella, S.; Yeganov, V.; Žáček, J.; Zálešák, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zhu, Y. C.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.

2007-11-01

A search for narrow baryonic resonances decaying into Ξ-π- or Ξ-π+ and their antiparticles is carried out with the H1 detector using deep inelastic scattering events at HERA in the range of negative photon four-momentum transfer squared 2 < Q2 < 100 GeV2. No signal is observed for a new baryonic state in the mass range 1600-2300 MeV in either the doubly charged or the neutral decay channels. The known Ξ(1530)0 is observed through its decay mode into Ξ-π+. Upper limits are given on the ratio of the production rates of new baryonic states, such as the hypothetical pentaquark states Ξ- 5q or Ξ0 5q, relative to the Ξ(1530)0 baryon state.

Measurement of the cross section of charmed hadrons and the nuclear dependence alpha

Energy Technology Data Exchange (ETDEWEB)

Blanco-Covarrubias, Ernesto Alejandro [Autonomous Univ. of San Luis Potosi, San Luis Potosi (Mexico)

2009-12-03

With data from the SELEX experiment we study charm hadro-production. We report the differential production cross sections as function of the longitudinal and transverse momentum, as well as for two different target materials, of 14 charmed hadron and/or their decay modes. This is the most extensive study to date. SELEX is a fixed target experiment at Fermilab with high forward acceptance; it took data during 1996-1997 with 600 GeV/c Σ^- and π^-, and 540 GeV/c proton and π⁺ beams. It used 5 target foils (two copper and three diamond). We use the results to determine α, used in parametrizing the production cross section as ∞ A^α, where A is the mass number of the target nuclei. We found within our statistics that α is independent of the longitudinal momentum fraction x_F in the interval 0.1 < x_F < 1.0, with α = 0.778 ± 0.014. The average value of α} for charm production by pion beams is α _meson = 0.850 ± 0.028. This is somewhat larger than the corresponding average α_baryon = 0.755 ± 0.016 for charm production by baryon beams (Σ^- and protons).

Phenomenology of Baryon Resonances

Energy Technology Data Exchange (ETDEWEB)

Doring, Michael [George Washington Univ., Washington, DC (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Landay, Justin [George Washington Univ., Washington, DC (United States); Mai, Maxim [George Washington Univ., Washington, DC (United States); Molina, Raquel [Univ. of Sao Paulo (Brazil); Ronchen, Deborah [Univ. of Bonn (Germany)

2018-04-01

Results for light baryon spectroscopy by different collaborations and the state of the art in the subfield is reviewed. Highlights contain common efforts of different phenomenology groups and the impact of recent high-precision data from ELSA, JLab, MAMI, and other facilities. Questions will be addressed, on one side, of how to proceed to reach conclusive answers in baryon spectroscopy, and, on the other side, how phenomenology can be connected to theory in a meaningful way.

The Compressed Baryonic Matter experiment

Directory of Open Access Journals (Sweden)

Seddiki Sélim

2014-04-01

Full Text Available The Compressed Baryonic Matter (CBM experiment is a next-generation fixed-target detector which will operate at the future Facility for Antiproton and Ion Research (FAIR in Darmstadt. The goal of this experiment is to explore the QCD phase diagram in the region of high net baryon densities using high-energy nucleus-nucleus collisions. Its research program includes the study of the equation-of-state of nuclear matter at high baryon densities, the search for the deconfinement and chiral phase transitions and the search for the QCD critical point. The CBM detector is designed to measure both bulk observables with a large acceptance and rare diagnostic probes such as charm particles, multi-strange hyperons, and low mass vector mesons in their di-leptonic decay. The physics program of CBM will be summarized, followed by an overview of the detector concept, a selection of the expected physics performance, and the status of preparation of the experiment.

Pentaquarks with hidden charm as hadroquarkonia

Energy Technology Data Exchange (ETDEWEB)

Eides, Michael I. [University of Kentucky, Department of Physics and Astronomy, Lexington, KY (United States); Petersburg Nuclear Physics Institute, St. Petersburg (Russian Federation); Petrov, Victor Yu. [Petersburg Nuclear Physics Institute, St. Petersburg (Russian Federation); Polyakov, Maxim V. [Petersburg Nuclear Physics Institute, St. Petersburg (Russian Federation); Ruhr-Universitaet Bochum, Institut fuer Theoretische Physik II, Bochum (Germany)

2018-01-15

We consider hidden charm pentaquarks as hadroquarkonium states in a QCD inspired approach. Pentaquarks arise naturally as bound states of quarkonia excitations and ordinary baryons. The LHCb P{sub c}(4450) pentaquark is interpreted as a ψ{sup '}-nucleon bound state with spin-parity J{sup P} = 3/2{sup -}. The partial decay width Γ(P{sub c}(4450) → J/ψ + N) ∼ 11 MeV is calculated and turned out to be in agreement with the experimental data for P{sub c}(4450). The P{sub c}(4450) pentaquark is predicted to be a member of one of the two almost degenerate hidden-charm baryon octets with spin-parities J{sup P} = 1/2{sup -}, 3/2{sup -}. The masses and decay widths of the octet pentaquarks are calculated. The widths are small and comparable with the width of the P{sub c}(4450) pentaquark, and the masses of the octet pentaquarks satisfy the Gell-Mann-Okubo relation. Interpretation of pentaquarks as loosely bound Σ{sub c} anti D* and Σ{sub c}{sup *} anti D* deuteronlike states is also considered. We determine quantum numbers of these bound states and calculate their masses in the one-pion exchange scenario. The hadroquarkonium and molecular approaches to exotic hadrons are compared and the relative advantages and drawbacks of each approach are discussed. (orig.)

New results on CLEO`s heavy quarks - bottom and charm

Energy Technology Data Exchange (ETDEWEB)

Menary, S. [Univ. of California, Santa Barbara, CA (United States)

1997-01-01

While the top quark is confined to virtual reality for CLEO, the increased luminosity of the Cornell Electron Storage Ring (CESR) and the improved photon detection capabilities of the CLEO`s {open_quotes}heavy{close_quotes} quarks - bottom and charm. I will describe new results in the B meson sector including the first observation of exclusive b {yields} ulv decays, upper limits on gluonic penguin decay rates, and precise measurements of semileptonic and hadronic b {yields} c branching fractions. The charmed hadron results that are discussed include the observation of isospin violation in D{sub s}*{sup +} decays, an update on measurements of the D{sub s}{sup +} decay constant, and the observation of a new excited {Xi}{sub c} charmed baryon. These measurements have had a large impact on our understanding of heavy quark physics.

Λ(1405) resonance in baryon-meson scattering with a bound state embedded in the continuum

International Nuclear Information System (INIS)

Takeuchi, Sachiko; Shimizu, Kiyotaka

2009-01-01

We investigate Λ(1405) as a resonance in a coupled-channels baryon-meson (Σπ-NK-Λη) scattering with a 'bound state embedded in the continuum' (BSEC). For this purpose, we solve the Lippmann-Schwinger equation including a BSEC with the semirelativistic kinematics in the momentum space. This BSEC is introduced by hand, as a state not originated from a simple baryon-meson system. We assume it comes from the three-quark state. There appears a resonance in the Σπ scattering below the NK threshold without introducing a BSEC when the NK channel has a strong attraction, just like the chiral unitary approach. Even if the baryon-meson interaction is weakened by using a lower-momentum cut-off parameter, a resonance also appears around 1405 MeV when a BSEC is introduced. The corresponding peak also has a large width, and the NK scattering length is well reproduced. The interaction whose channel dependence is the same as the one originated from the color-magnetic interaction, where no NK attraction exists, also gives a broad peak with help of a BSEC. In order to reproduce the observed NK scattering length, the calculation including a BSEC seems to be preferable. Our calculation gives an appropriate NK scattering length when the BSEC contribution to the resonance is roughly half that of the NK channel.

Charmed and strange baryon production in 29-GeV electron positron collisions

International Nuclear Information System (INIS)

Klein, S.R.

1988-01-01

Baryon production is one of the least understood areas of hadron production in electron positron collisions. Early models of hadronization predicted that very few baryons should be produced. However, experiments have shown a very substantial rate of baryon production, and many different models have been proposed to explain this. One way to test these models, and to further probe the hadronization process is to measure the production rates of different types of baryons. This dissertation presents measurements of the production rates of baryons with different strangeness and spin. The analyses presented here use data taken with the Mark II detector at the PEP storage ring, operating at a center of mass energy of 29 GeV. The Ξ - production rate is measured to be 0.017 ± 0.004 ± 0.004 per hadronic event, Ω - production is measured to be 0.014 ± 0.006 ± 0.004 per hadronic event, and Ξ *0 production is less than 0.006 per hadronic event at a 90% confidence level. These measurements place strong constraints on models of baryon production. In particular, the unexpectedly high rate of Ω - production is difficult to explain in any disquark based model. Semileptonic Λ c + decays have also been observed, with σ(e + e - → Λ c X) * Br(Λ c → eΛX) = 0.0031 ± 0.0012 ± 0.0010 per hadronic event, and σ(e + e - → Λ c X) * Br(Λ c → μΛX) = 0.0024 ± 0.0024 ± 0.0007 per hadronic event. Because neither the branching ratios nor the production rate are well known, it is difficult to interpret these results

Meson-baryon components in the states of the baryon decuplet

Energy Technology Data Exchange (ETDEWEB)

Aceti, F.; Oset, E. [Centro Mixto Universidad de Valencia-CSIC, Institutos de Investigacion de Paterna, Departamento de Fisica Teorica y IFIC, Valencia (Spain); Kavli Institute for Theoretical Physics China, Beijing (China); Dai, L.R. [Liaoning Normal University, Department of Physics, Dalian (China); Kavli Institute for Theoretical Physics China, Beijing (China); Geng, L.S. [Beihang University, School of Physics and Nuclear Energy Engineering and International Research Center for Nuclei and Particles in the Cosmos, Beijing (China); Zhang, Y. [Liaoning Normal University, Department of Physics, Dalian (China)

2014-03-15

We apply an extension of the Weinberg compositeness condition on partial waves of L = 1 and resonant states to determine the weight of the meson-baryon component in the Δ(1232) resonance and the other members of the J{sup P} = (3)/(2){sup +} baryon decuplet. We obtain an appreciable weight of πN in the Δ(1232) wave function, of the order of 60%, which looks more natural when one recalls that experiments on deep inelastic and Drell Yan give a fraction of πN component of 34% for the nucleon. We also show that, as we go to higher energies in the members of the decuplet, the weights of the meson-baryon component decrease and they already show a dominant part for a genuine, non-meson-baryon, component in the wave function. We write a section to interpret the meaning of the Weinberg sum rule when it is extended to complex energies and another one for the case of an energy-dependent potential. (orig.)

Calculation of hadronic transition amplitudes in charm physics

International Nuclear Information System (INIS)

Klein, Christoph

2011-01-01

Transitions of charmed hadrons are of significant importance, since they provide possibilities to extract the CKM matrix elements V cd and V cs from experimental data as well as interesting channels to search for new physics effects. However, quarks are bound in hadrons, and it is necessary to describe this effect in a reliable way, to study the underlying flavour dynamics. For this, one has to use nonperturbative tools, to determine the corresponding transition amplitudes. The results of such calculations can furthermore be of use, to test the predictions of QCD and to contribute to a deeper understanding of the structure of hadrons. In this thesis two topics are investigated using the method of QCD light-cone sum rules (LCSRs). The first topic consists in the form factors of the semileptonic decays D → πlν l and D → Klν l , for which new results are calculated using up-to-date input values. Since LCSRs are not applicable in the whole range of kinematics, they are extrapolated by the use of appropriate parametrisations and the results agree well with experimental data. The second topic are the transitions of charmed baryons to a nucleon. Here the corresponding transition form factors and in addition the hadronic Λ c D (*) N and Σ c D (*) N coupling constants are calculated - the latter by the consideration of double dispersion relations. These coupling constants are of special interest for the description of hadronic interactions, like open charm production in proton-antiprotoncollisions. Furthermore there appears the problem, that both parity states of a baryon contribute to the considered functional representation, for which a consistent way to separate them is presented. (orig.)

Exotic dynamically generated baryons with negative charm quantum number

NARCIS (Netherlands)

Gamermann, D.; Garcia-Recio, C.; Nieves, J.; Salcedo, L. L.; Tolos, L.

2010-01-01

Following a model based on the SU(8) symmetry that treats heavy pseudoscalars and heavy vector mesons on an equal footing, as required by heavy quark symmetry, we study the interaction of baryons and mesons in coupled channels within an unitary approach that generates dynamically poles in the

The Compressed Baryonic Matter Experiment at FAIR

International Nuclear Information System (INIS)

Heuser, Johann M.

2013-01-01

The Compressed Baryonic Matter (CBM) experiment will explore the phase diagram of strongly interacting matter in the region of high net baryon densities. The experiment is being laid out for nuclear collision rates from 0.1 to 10 MHz to access a unique wide spectrum of probes, including rarest particles like hadrons containing charm quarks, or multi-strange hyperons. The physics programme will be performed with ion beams of energies up to 45 GeV/nucleon. Those will be delivered by the SIS-300 synchrotron at the completed FAIR accelerator complex. Parts of the research programme can already be addressed with the SIS-100 synchrotron at the start of FAIR operation in 2018. The initial energy range of up to 11 GeV/nucleon for heavy nuclei, 14 GeV/nucleon for light nuclei, and 29 GeV for protons, allows addressing the equation of state of compressed nuclear matter, the properties of hadrons in a dense medium, the production and propagation of charm near the production threshold, and exploring the third, strange dimension of the nuclide chart. In this article we summarize the CBM physics programme, the preparation of the detector, and give an outline of the recently begun construction of the Facility for Antiproton and Ion Research

SU(6), baryonic decays of B-mesons and CP

International Nuclear Information System (INIS)

Wu, D.

1990-01-01

In this paper the four fermion weak decay Hamiltonian is expressed in terms of quark-antiquark creation operators with specific spin orientations. Then the SU(6) symmetry of the strong interactions among light quarks is imposed to find 8 invariant decay amplitudes for two body charmful baryonic decays of the B-mesons, 3 S-waves, 4 P- waves and 1 D-wave. Λ c branching ratio and some exclusive branching ratios are calculated based on the assumption of two body dominance in baryonic decay modes. Results on two body mesonic decays are also given. Relation between the SU(6) scheme and the quark diagram scheme is discussed

Charmed particles production in pA -interactions at √s = 11.8 GeV

Energy Technology Data Exchange (ETDEWEB)

Aleev, A.; Balandin, V.; Boguslavsky, M.; Dunun, V.; Gavrishchuk, O.; Furmanec, N.; Kireev, V.; Konstantinov, V.; Kosarev, I.; Kokoulina, E.; Kuzmin, N.; Lanshikov, G.; Nikitin, V.; Petukhov, Yu.; Rufanov, I.; Topuria, T.; Yukaev, A. [Joint Institute for Nuclear Research, Dubna, Moscow region (Russian Federation); Ardashev, E.; Afonin, A.; Bogolyubsky, M.; Golovnia, S.; Gorokhov, S.; Golovkin, V.; Kholodenko, A.; Kiriyakov, A.; Kurchaninov, L.; Mitrofanov, G.; Moiseev, A.; Petrov, V.; Pleskach, A.; Riadovikov, V.; Ronjin, V.; Senko, V.; Shalanda, N.; Soldatov, M.; Tsyupa, Yu.; Vasiliev, M.; Vorobiev, A.; Yakimchuk, V.; Zapolsky, V.; Zmushko, V. [Institute for High Energy Physics, Protvino, Moscow region (Russian Federation); Basiladze, S.; Bogdanova, G.; Grishin, N.; Grishkevich, Ya.; Ermolov, P.; Karmanov, D.; Kozlov, V.; Kramarenko, V.; Kubarovsky, A.; Larichev, A.; Leflat, A.; Lyutov, S.; Merkin, M.; Orfanitsky, S.; Popov, V.; Tikhonova, L.; Vischnevskaya, A.; Volkov, V.; Voronin, A.; Zotkin, S.; Zotkin, D.; Zverev, E. [Moscow State University, Skobeltsyn Institute of Nuclear Physics (SINP MSU), Federal State Budget Educational Institution of Higher Education M.V. Lomonosov, Moscow (Russian Federation); Collaboration: SVD-2 Collaboration

2017-03-15

The results of the SERP-E-184 experiment at the U-70 accelerator (IHEP, Protvino) are presented. Interactions of the 70GeV proton beam with carbon, silicon and lead targets were studied to detect decays of charmed D{sup 0}, anti D{sup 0}, D{sup +}, D{sup -} mesons and Λ{sub c}{sup +} baryon near their production threshold. Measurements of lifetimes and masses have shown a good agreement with PDG data. The inclusive cross-sections of charm production and their A-dependences have been obtained. The yields of these particles are compared with the theoretical predictions and the data of other experiments. The measured cross-section of the total open charm production (σ{sub tot}(c anti c) = 7.1 ± 2.3(stat) ± 1.4(syst) μb/nucleon) at the collision c.m. energy √s = 11.8 GeV is well above the QCD model predictions. The contributions of different kinds of charmed particles to the total cross-section of the open charm production in proton-nucleus interactions vary with energy. (orig.)

Feasibility studies for the open-charm production in proton-antiproton reactions for the PANDA experiment

Energy Technology Data Exchange (ETDEWEB)

Vejdani, Solmaz [KVI-CART, University of Groningen (Netherlands); Forschungszentrum Juelich, Juelich (Germany); Collaboration: PANDA-Collaboration

2016-07-01

The PANDA experiment is one of the pillars of the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany. The PANDA physics program is focused on answering fundamental questions related to Quantum Chromodynamics (QCD), mostly in the non-perturbative energy regime. Spectroscopy exploiting Λc-baryons that are composed of a heavy charm valence quark and two light valence quarks is an integral part of the PANDA physics program. Such systems can systematically provide information on various key features of QCD, such as heavy-quark symmetry, chiral symmetry breaking, and the nature of exotic states. In this work, the experimental feasibility of studying the production mechanisms of associative open-charm baryons in antiproton-proton annihilations is investigated by using Monte Carlo simulations. I present results obtained for the channel p anti p → Λ{sup -}{sub c}Λ{sub c}, highlighting the detector performances (efficiencies and resolutions) and the statistical significance that can be achieved with the foreseen luminosities.

Baryon spectroscopy and the omega minus

International Nuclear Information System (INIS)

Samios, N.P.

1994-01-01

In this report, I will mainly discuss baryon resonances with emphasis on the discovery of the Ω - . However, for completeness, I will also present some data on the meson resonances which together with the baryons led to the uncovering of the SU(3) symmetry of particles and ultimately to the concept of quarks

The properties of charmonium and charm particles

International Nuclear Information System (INIS)

Schopper, H.

1977-12-01

An impressive amount of data has been accumulated over the past three years which support strongly the idea that elementary particles are composed of four quarks instead of three. All the predictions based on the existence of the fourth, the charm quark, have in principal been born out by experiments and from detailed investigations very interesting results could be obtained for the strong and the weak interaction. Most of these results have been obtained with electron-positron storage rings, and only these will be discussed in this report. Additional data from hadronic or neutrino interactions are in general agreement with the e + e - data and will not be discussed here. This series of lectures will be entirely devoted to a discussion of mesons, i.e. quark-antiquark systems. Although some indications have been found for the existence of charmed baryons, these data are still rather scanty. In the last chapter we shall also discuss the upsilon particle. (orig.) [de

Baryon spectroscopy and the omega minus

Energy Technology Data Exchange (ETDEWEB)

Samios, N.P.

1994-12-31

In this report, I will mainly discuss baryon resonances with emphasis on the discovery of the {Omega}{sup {minus}}. However, for completeness, I will also present some data on the meson resonances which together with the baryons led to the uncovering of the SU(3) symmetry of particles and ultimately to the concept of quarks.

Prompt neutrinos from atmospheric charm in the general-mass variable-flavor-number scheme

International Nuclear Information System (INIS)

Benzke, M.; Garzelli, M.V.; Kniehl, B.A.; Kramer, G.; Moch, S.; Sigl, G.

2017-08-01

We present predictions for the prompt-neutrino flux arising from the decay of charmed mesons and baryons produced by the interactions of high-energy cosmic rays in the Earth's atmosphere, making use of a QCD approach on the basis of the general-mass variable-flavor-number scheme for the description of charm hadroproduction at NLO, complemented by a consistent set of fragmentation functions. We compare the theoretical results to those already obtained by our and other groups with different theoretical approaches. We provide comparisons with the experimental results obtained by the IceCube Collaboration in two different analyses and we discuss the implications for parton distribution functions.

Outlook for baryon spectroscopy

International Nuclear Information System (INIS)

Tripp, R.D.

1976-09-01

The review of baryon spectroscopy includes a number of new generation experiments with greatly improved statistics which have emerged and are enhancing experimental knowledge of baryon resonances. The future research directions are pointed out, and some problems and deficiencies which can be resolved with contemporary techniques are mentioned

Baryons with chromodynamics

International Nuclear Information System (INIS)

Isgur, N.

1981-01-01

Many of the phenomenological difficulties of the non-relativistic quark model for baryons are overcome when some current prejudices from chromodynamics about quark forces are imposed. The effects of flavour independent confinement, symmetry breaking through quark masses, and colour hyperfine interactions are most prominent, leading to a satisfactory understanding of both the spectroscopy of low-lying baryons and of the signs and magnitudes of baryon couplings. The previously worrisome absence in partial wave analyses of a large number of the states expected in the nonrelativistic quark model is explained in terms of decouplings of the resonances from their elastic channels

Magnetic moments of confined quarks and baryons in an independent-quark model based on Dirac equation with power-law potential

International Nuclear Information System (INIS)

Barik, N.; Das, M.

1983-01-01

The effect of confinement on the magnetic moment of a quark has been studied in a simple independent-quark model based on the Dirac equation with a power-law potential. The magnetic moments so obtained for the constituent quarks, which are found to be significantly different from their corresponding Dirac moments, are used in predicting the magnetic moments of baryons in the nucleon octet as well as those in the charmed and b-flavored sectors. We not only get an improved result for the proton magnetic moment, but the calculation for the rest of the nucleon octet also turns out to be in reasonable agreement with experiment. The overall predictions for the charmed and b-flavored baryons are also comparable with other model predictions

The width of the Δ-resonance at two loop order in baryon chiral perturbation theory

Energy Technology Data Exchange (ETDEWEB)

Gegelia, Jambul, E-mail: j.gegelia@fz-juelich.de [Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, D-52425 Jülich (Germany); Tbilisi State University, 0186 Tbilisi, Georgia (United States); Meißner, Ulf-G., E-mail: meissner@hiskp.uni-bonn.de [Helmholtz Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universität Bonn, D-53115 Bonn (Germany); Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, D-52425 Jülich (Germany); Siemens, Dmitrij, E-mail: dmitrij.siemens@rub.de [Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Yao, De-Liang, E-mail: d.yao@fz-juelich.de [Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, D-52425 Jülich (Germany)

2016-12-10

We calculate the width of the delta resonance at leading two-loop order in baryon chiral perturbation theory. This gives a correlation between the leading pion–nucleon–delta and pion–delta couplings, which is relevant for the analysis of pion–nucleon scattering and other processes.

Baryon and meson phenomenology in the extended Linear Sigma Model

Energy Technology Data Exchange (ETDEWEB)

Giacosa, Francesco; Habersetzer, Anja; Teilab, Khaled; Eshraim, Walaa; Divotgey, Florian; Olbrich, Lisa; Gallas, Susanna; Wolkanowski, Thomas; Janowski, Stanislaus; Heinz, Achim; Deinet, Werner; Rischke, Dirk H. [Institute for Theoretical Physics, J. W. Goethe University, Max-von-Laue-Str. 1, 60438 Frankfurt am Main (Germany); Kovacs, Peter; Wolf, Gyuri [Institute for Particle and Nuclear Physics, Wigner Research Center for Physics, Hungarian Academy of Sciences, H-1525 Budapest (Hungary); Parganlija, Denis [Institute for Theoretical Physics, Vienna University of Technology, Wiedner Hauptstr. 8-10, A-1040 Vienna (Austria)

2014-07-01

The vacuum phenomenology obtained within the so-called extended Linear Sigma Model (eLSM) is presented. The eLSM Lagrangian is constructed by including from the very beginning vector and axial-vector d.o.f., and by requiring dilatation invariance and chiral symmetry. After a general introduction of the approach, particular attention is devoted to the latest results. In the mesonic sector the strong decays of the scalar and the pseudoscalar glueballs, the weak decays of the tau lepton into vector and axial-vector mesons, and the description of masses and decays of charmed mesons are shown. In the baryonic sector the omega production in proton-proton scattering and the inclusion of baryons with strangeness are described.

Nonleptonic decays of 1/2+-baryons and pseudo-connected-line diagrams, 1

International Nuclear Information System (INIS)

Abe, Yoshikazu; Fujii, Kanji

1978-01-01

Under the SU(4)-20''-spurion dominance in nonleptonic weak decays, we investigate algebraic structures of the effective Hamiltonian H sub(eff) which describes the main features of the nonleptonic weak decays of ordinary baryons. When H sub(eff) is written by using 20'-baryon (1/2 + ) wave function of the form B sub(α)sup([βγ]), one can select out of H sub(eff) two terms which describe most simply the main features of the P-wave amplitudes for ordinary baryons. Only these terms are s-u dual in the sense of 'pseudo-connected-line diagrams' (pseudo-CLD's) obtained by writing CLD's with 4- and 4*-lines corresponding directly to the lower and the upper indices of B sub(α)sup([βγ]). By assuming Lee-Sugawara relation and s-u dual property of the P-wave amplitudes, various relations among ordinary and charmed baryon decays are derived. Comments on the parity-violating amplitudes are also given. (auth.)

Observation of two new $\\Xi_b^-$ baryon resonances

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; Andreassen, Rolf; 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; Belogurov, Sergey; Belous, Konstantin; 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; Bjørnstad, Pål Marius; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borgia, Alessandra; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; 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; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casanova Mohr, Raimon; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; 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 Christopher; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dalseno, Jeremy; David, Pascal; 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 Domenico, Antonio; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; 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Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Whitehead, Mark; Wiedner, Dirk; Wilkinson, Guy; Wilkinson, Michael; Williams, Matthew; Williams, Mike; Wilschut, Hans; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xing, Zhou; Xu, Zhirui; Yang, Zhenwei; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Wen Chao; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang

2015-01-01

Two structures are observed close to the kinematic threshold in the $\\Xi_b^0\\pi^-$ mass spectrum in a sample of proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb$^{-1}$ recorded by the LHCb experiment. In the quark model, two baryonic resonances with quark content $bds$ are expected in this mass region: the spin-parity $J^P = \\frac{1}{2}^+$ and $J^P=\\frac{3}{2}^+$ states, denoted $\\Xi_b^{\\prime -}$ and $\\Xi_b^{*-}$. Interpreting the structures as these resonances, we measure the mass differences and the width of the heavier state to be \\begin{eqnarray*} m(\\Xi_b^{\\prime -}) - m(\\Xi_b^0) - m(\\pi^{-}) &=& 3.653 \\pm 0.018 \\pm 0.006~{\\rm MeV}/c^2, \\\\ m(\\Xi_b^{*-}) - m(\\Xi_b^0) - m(\\pi^{-}) &=& 23.96 \\pm 0.12\\pm 0.06~{\\rm MeV}/c^2, \\\\ \\Gamma(\\Xi_b^{*-}) &=& 1.65 \\pm 0.31 \\pm 0.10~{\\rm MeV}, \\end{eqnarray*} where the first and second uncertainties are statistical and systematic, respectively. The width of the lighter state is consistent with zero, and we place ...

A new look at the Y tetraquarks and Ω{sub c} baryons in the diquark model

Energy Technology Data Exchange (ETDEWEB)

Ali, Ahmed [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Maiani, Luciano [CERN, Theory Division, Geneva (Switzerland); Borisov, Anatoly V. [M.V. Lomonosov Moscow State University, Faculty of Physics, Moscow (Russian Federation); Ahmed, Ishtiaq; Rehman, Abdur [Quaid-i-Azam University, National Centre for Physics, Islamabad (Pakistan); Aslam, M.J. [Quaid-i-Azam University, Department of Physics, Islamabad (Pakistan); Parkhomenko, Alexander Ya. [P.G. Demidov Yaroslavl State University, Department of Theoretical Physics, Yaroslavl (Russian Federation); Polosa, Antonio D. [Sapienza Universita di Roma, Dipartimento di Fisica, Rome (Italy); INFN, Rome (Italy)

2018-01-15

We analyze the hidden charm P-wave tetraquarks in the diquark model, using an effective Hamiltonian incorporating the dominant spin-spin, spin-orbit and tensor interactions. We compare with other P-wave systems such as P-wave charmonia and the newly discovered Ω{sub c} baryons, analysed recently in this framework. Given the uncertain experimental situation on the Y states, we allow for different spectra and discuss the related parameters in the diquark model. In addition to the presently observed ones, we expect many more states in the supermultiplet of L = 1 diquarkonia, whose J{sup PC} quantum numbers and masses are worked out, using the parameters from the currently preferred Y-states pattern. The existence of these new resonances would be a decisive footprint of the underlying diquark dynamics. (orig.)

Search for charm production in direct decays of the Υ(1S) resonance

International Nuclear Information System (INIS)

Albrecht, H.; Ehrlichmann, H.; Hamacher, T.; Krueger, A.; Nau, A.; Nippe, A.; Nowak, S.; Reidenbach, M.; Schaefer, M.; Schroeder, H.; Schulz, H.D.; Walter, M.; Wurth, R.; Appuhn, R.D.; Hast, C.; Herrera, G.; Kolanoski, H.; Lange, A.; Lindner, A.; Mankel, R.; Schieber, M.; Siegmund, T.; Spaan, B.; Thurn, H.; Toepfer, D.; Walther, A.; Wegener, D.; Britton, D.I.; Charlesworth, C.E.K.; Edwards, K.W.; Hyatt, E.R.F.; Kapitza, H.; Krieger, P.; MacFarlane, D.B.; Patel, P.M.; Prentice, J.D.; Saull, P.R.B.; Seidel, S.C.; Tzamariudaki, K.; Van de Water, R.G.; Yoon, T.S.; Ressling, D.; Schmidtler, M.; Schneider, M.; Schubert, K.R.; Strahl, K.; Waldi, R.; Weseler, S.

1992-01-01

The production of D * (2010) + and J/ψ mesons and of prompt leptons has been investigated in e + e - interactions at the Υ(1S) resonance energy. The data were collected at the storage ring DORIS II at DESY with the ARGUS detector. We obtain upper limits of BR dir (Υ(1S)→D * (2010) ± +X) p >0.2) and BR dir (Υ(1S)→J/ψ+X) -3 , both at the 90% confidence level. From the prompt lepton analysis, a model dependent limit of BR dir (Υ(1S)→Y c +X) c denoting a charm-containing particle) is derived. (orig.)

Study of \\Omega_c^0 and \\Omega_c^{*0} Baryons at Belle

OpenAIRE

Solovieva, E.; Chistov, R.; Collaboration, for the Belle

2008-01-01

We report results from a study of the charmed double strange baryons \\Omega_c^0 and \\Omega_c^{*0} at Belle. The \\Omega_c^0 is reconstructed using the \\Omega_c^0 --> \\Omega^- \\pi^+ decay mode, and its mass is measured to be (2693.6 \\pm 0.3 {+1.8 \\atop -1.5}) MeV/c^2. The \\Omega_c^{*0} baryon is reconstructed in the \\Omega_c^0 \\gamma mode. The mass difference M_{\\Omega_c^{*0}} - M_{\\Omega_c^0} is measured to be (70.7 \\pm 0.9 {+0.1 \\atop -0.9}) MeV/c^2. The analysis is performed using 673 fb^{-1...

Baryon spectrum with Nƒ=2+1+1 twisted mass fermions

DEFF Research Database (Denmark)

Alexandrou, C.; Drach, V.; Jansen, K.

2014-01-01

The masses of the low-lying baryons are evaluated using a total of ten ensembles of dynamical twisted mass fermion gauge configurations. The simulations are performed using two degenerate flavors of light quarks, and a strange and a charm quark fixed to approximately their physical values....... The light sea quarks correspond to pseudo scalar masses in the range of about 210 to 430 MeV. We use the Iwasaki improved gluonic action at three values of the coupling constant corresponding to lattice spacing a = 0.094, 0.082 and 0.065 fm determined from the nucleon mass. We check for both finite volume...... and cutoff effects on the baryon masses. We examine the issue of isospin symmetry breaking for the octet and decuplet baryons and its dependence on the lattice spacing. We show that in the continuum limit isospin breaking is consistent with zero, as expected. We performed a chiral extrapolation of the forty...

Few-body quark dynamics for doubly heavy baryons and tetraquarks

Science.gov (United States)

Richard, Jean-Marc; Valcarce, Alfredo; Vijande, Javier

2018-03-01

We discuss the adequate treatment of the three- and four-body dynamics for the quark model picture of double-charm baryons and tetraquarks. We stress that the variational and Born-Oppenheimer approximations give energies very close to the exact ones, while the diquark approximation might be somewhat misleading. The Hall-Post inequalities also provide very useful lower bounds that exclude the possibility of stable tetraquarks for some mass ratios and some color wave functions.

Scattering phases for meson and baryon resonances on general moving-frame lattices

Energy Technology Data Exchange (ETDEWEB)

Goeckeler, M. [Regensburg Univ. (Germany). Institut fuer Theoretische Physik; Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Lage, M.; Rusetsky, A. [Bonn Univ. (Germany). Helmholtz-Inst. fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics; Meissner, U.G. [Bonn Univ. (Germany). Helmholtz-Inst. fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics; Forschungszentrum Juelich GmbH (Germany). Inst. fuer Kernphysik; Forschungszentrum Juelich (Germany). Juelich Center for Hadron Physics and JARA - High Performance Computing; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Division; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Zanotti, J.M. [Adelaide Univ., SA (Australia). CSSM, School of Chemistry and Physics

2012-06-15

A proposal by Luescher enables one to compute the scattering phases of elastic two-body systems from the energy levels of the lattice Hamiltonian in a finite volume. In this work we generalize the formalism to S-, P- and D-wave meson and baryon resonances, and general total momenta. Employing nonvanishing momenta has several advantages, among them making a wider range of energy levels accessible on a single lattice volume and shifting the level crossing to smaller values of m{sub {pi}}L.

Baryon resonances in pion- and photon-induced hadronic reactions

International Nuclear Information System (INIS)

Roenchen, Deborah

2014-01-01

The aim of the present work is the analysis of the baryon spectrum in the medium-energy regime. At those energies, a perturbative treatment of Quantum Chromodynamics, that is feasible in the high-energy regime, is not possible. Chiral perturbation theory, the low-energy effective theory of the strong interaction, is limited to the lowest excited states and does not allow to analyze the complete resonance region. For the latter purpose, dynamical coupled-channel approaches provide an especially suited framework. In the present study, we apply the Juelich model, a dynamical coupled-channel model developed over the years, to analyze pion- and photon-induced hadronic reactions in a combined approach. In the Juelich model, the interaction of the mesons and baryons is built of t- and u-channel exchange diagrams based on an effective Lagrangian. Genuine resonances are included as s-channel states. The scattering potential is unitarized in a Lippmann-Schwinger-type equation. Analyticity is preserved, which is a prerequisite for a reliable extraction of resonance parameters in terms of pole positions and residues in the complex energy plane. Upon giving an introduction to the subject in Chap. 1 and showing selected results in Chap. 2, we will describe the simultaneous analysis of elastic πN scattering and the reactions π - p → ηn, K 0 Λ, K + Σ - , K 0 Σ 0 and π + p→K + Σ + within the Juelich framework in Chap. 3. The free parameters of the model are adjusted to the GWU/SAID analysis of elastic πN scattering and, in case of the inelastic reactions, to experimental data. Partial waves up to J=9/2 are included and we consider the world data set from threshold up to E∝2.3 GeV. We show our fit results compared to differential and total cross sections, to polarizations and to measurements of the spin-rotation parameter. Finally, we present the results of a pole search in the complex energy plane of the scattering amplitude and discuss the extracted resonance

Study of the baryon-baryon interaction in nucleon-nucleon and pion-deuteron scattering

International Nuclear Information System (INIS)

Fuchs, M.

1993-01-01

After the definition of the Hamiltonian in general form by meson production and absorption the transition to operators pursued, which connect only spaces with definite meson numbers. In this approximation first the self-energy of a single baryon was calculated in its full energy and momentum dependence. Then the formal expressions for the T matrices of nucleon-nucleon and pion-deuteron scattering were derived. The essential components of these expressions are the baryon-baryon T matrix ant transition amplitudes from pion-deuteron channels to baryon-baryon states. The central chapter dealt with the calculation of the baryon-baryon interaction for the general form of the vertices, with the solution of the binding problem and the baryon-baryon T matrix. Finally followed the results on the nucleon-nucleon and pion-deuteron scattering. For this first the transition amplitudes from pion-deuteron states to intermediate baryon-baryon states and the Born graphs of the pion-deuteron scattering had to be calculated. After some remarks to the transition from partial-wave decomposed T matrices to scattering observables an extensive representation of the total, partial, and differential cross sections and a series of spin observables (analyzing powers and spin correlations) for the elastic proton-proton, neutron-proton, and pion-deuteron scattering as well for the fusion reaction pp→πd and the breakup reaction πd→pp follows. Thereby the energies reached from the nucleon-nucleon respectively pion-deuteron threshold up to 100 MeV above the delta resonance

Observation of two new Ξ(b)(-) baryon resonances.

Science.gov (United States)

Aaij, R; Adeva, B; Adinolfi, M; Affolder, A; Ajaltouni, Z; Akar, S; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amerio, S; Amhis, Y; An, L; Anderlini, L; Anderson, J; Andreassen, R; Andreotti, M; Andrews, J E; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Baalouch, M; Bachmann, S; Back, J J; Badalov, A; Baesso, C; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Batozskaya, V; Battista, V; Bay, A; Beaucourt, L; Beddow, J; Bedeschi, F; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Benton, J; Berezhnoy, A; Bernet, R; Bertolin, A; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Borsato, M; Bowcock, T J V; Bowen, E; Bozzi, C; Brett, D; Britsch, M; Britton, T; Brodzicka, J; Brook, N H; Bursche, A; Buytaert, J; Cadeddu, S; Calabrese, R; Calvi, M; Calvo Gomez, M; Campana, P; Campora Perez, D; Capriotti, L; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carson, L; Carvalho Akiba, K; Casanova Mohr, R C M; Casse, G; Cassina, L; Castillo Garcia, L; Cattaneo, M; Cauet, Ch; Cenci, R; Charles, M; Charpentier, Ph; Chefdeville, M; Chen, S; Cheung, S-F; Chiapolini, N; Chrzaszcz, M; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coco, V; Cogan, J; Cogneras, E; Cogoni, V; Cojocariu, L; Collazuol, G; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Coquereau, S; Corti, G; Corvo, M; Counts, I; Couturier, B; Cowan, G A; Craik, D C; Crocombe, A C; Cruz Torres, M; Cunliffe, S; Currie, R; D'Ambrosio, C; Dalseno, J; David, P; David, P N Y; Davis, A; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Silva, W; De Simone, P; Dean, C-T; Decamp, D; Deckenhoff, M; Del Buono, L; Déléage, N; Derkach, D; Deschamps, O; Dettori, F; Dey, B; Di Canto, A; Di Domenico, A; Dijkstra, H; Donleavy, S; Dordei, F; Dorigo, M; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dreimanis, K; Dujany, G; Dupertuis, F; Durante, P; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Ely, S; Esen, S; Evans, H-M; Evans, T; Falabella, A; Färber, C; Farinelli, C; Farley, N; Farry, S; Fay, R; Ferguson, D; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fiore, M; Fiorini, M; Firlej, M; Fitzpatrick, C; Fiutowski, T; Fol, P; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Fu, J; Furfaro, E; Gallas Torreira, A; Galli, D; Gallorini, S; Gambetta, S; Gandelman, M; Gandini, P; Gao, Y; García Pardiñas, J; Garofoli, J; Garra Tico, J; Garrido, L; Gascon, D; Gaspar, C; Gastaldi, U; Gauld, R; Gavardi, L; Gazzoni, G; Geraci, A; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gianelle, A; Gianì, S; Gibson, V; Giubega, L; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gotti, C; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graverini, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Griffith, P; Grillo, L; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hamilton, B; Hampson, T; Han, X; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; He, J; Head, T; Heijne, V; Hennessy, K; Henrard, P; Henry, L; Hernando Morata, J A; van Herwijnen, E; Hess, M; Hicheur, A; Hill, D; Hoballah, M; Hombach, C; Hulsbergen, W; Hussain, N; Hutchcroft, D; Hynds, D; Idzik, M; Ilten, P; Jacobsson, R; Jaeger, A; Jalocha, J; Jans, E; Jaton, P; Jawahery, A; Jing, F; John, M; Johnson, D; Jones, C R; Joram, C; Jost, B; Jurik, N; Kandybei, S; Kanso, W; Karacson, M; Karbach, T M; Karodia, S; Kelsey, M; Kenyon, I R; Ketel, T; Khanji, B; Khurewathanakul, C; Klaver, S; Klimaszewski, K; Kochebina, O; Kolpin, M; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucewicz, W; Kucharczyk, M; Kudryavtsev, V; Kurek, K; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanfranchi, G; Langenbruch, C; Langhans, B; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Leroy, O; Lesiak, T; Leverington, B; Li, Y; Likhomanenko, T; Liles, M; Lindner, R; Linn, C; Lionetto, F; Liu, B; Lohn, S; Longstaff, I; Lopes, J H; Lowdon, P; Lucchesi, D; Luo, H; Lupato, A; Luppi, E; Lupton, O; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Malde, S; Malinin, A; Manca, G; Mancinelli, G; Mapelli, A; Maratas, J; Marchand, J F; Marconi, U; Marin Benito, C; Marino, P; Märki, R; Marks, J; Martellotti, G; Martinelli, M; Martinez Santos, D; Martinez Vidal, F; Martins Tostes, D; Massafferri, A; Matev, R; Mathe, Z; Matteuzzi, C; Mazurov, A; McCann, M; McCarthy, J; McNab, A; McNulty, R; McSkelly, B; Meadows, B; Meier, F; Meissner, M; Merk, M; Milanes, D A; Minard, M-N; Moggi, N; Molina Rodriguez, J; Monteil, S; Morandin, M; Morawski, P; Mordà, A; Morello, M J; Moron, J; Morris, A-B; Mountain, R; Muheim, F; Müller, K; Mussini, M; Muster, B; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neri, N; Neubert, S; Neufeld, N; Neuner, M; Nguyen, A D; Nguyen, T D; Nguyen-Mau, C; Nicol, M; Niess, V; Niet, R; Nikitin, N; Nikodem, T; Novoselov, A; O'Hanlon, D P; Oblakowska-Mucha, A; Obraztsov, V; Ogilvy, S; Okhrimenko, O; Oldeman, R; Onderwater, C J G; Orlandea, M; Otalora Goicochea, J M; Otto, A; Owen, P; Oyanguren, A; Pal, B K; Palano, A; Palombo, F; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Pappalardo, L L; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Patrignani, C; Pearce, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perret, P; Pescatore, L; Pesen, E; Petridis, K; Petrolini, A; Picatoste Olloqui, E; Pietrzyk, B; Pilař, T; Pinci, D; Pistone, A; Playfer, S; Plo Casasus, M; Polci, F; Poluektov, A; Polyakov, I; Polycarpo, E; Popov, A; Popov, D; Popovici, B; Potterat, C; Price, E; Price, J D; Prisciandaro, J; Pritchard, A; Prouve, C; Pugatch, V; Puig Navarro, A; Punzi, G; Qian, W; Rachwal, B; Rademacker, J H; Rakotomiaramanana, B; Rama, M; Rangel, M S; Raniuk, I; Rauschmayr, N; Raven, G; Redi, F; Reichert, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, S; Rihl, M; Rinnert, K; Rives Molina, V; Robbe, P; Rodrigues, A B; Rodrigues, E; Rodriguez Perez, P; Roiser, S; Romanovsky, V; Romero Vidal, A; Rotondo, M; Rouvinet, J; Ruf, T; Ruiz, H; Ruiz Valls, P; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salustino Guimaraes, V; Sanchez Mayordomo, C; Sanmartin Sedes, B; Santacesaria, R; Santamarina Rios, C; Santovetti, E; Sarti, A; Satriano, C; Satta, A; Saunders, D M; Savrina, D; Schiller, M; Schindler, H; Schlupp, M; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M-H; Schwemmer, R; Sciascia, B; Sciubba, A; Semennikov, A; Sepp, I; Serra, N; Serrano, J; Sestini, L; Seyfert, P; Shapkin, M; Shapoval, I; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, V; Shires, A; Silva Coutinho, R; Simi, G; Sirendi, M; Skidmore, N; Skillicorn, I; Skwarnicki, T; Smith, N A; Smith, E; Smith, E; Smith, J; Smith, M; Snoek, H; Sokoloff, M D; Soler, F J P; Soomro, F; Souza, D; Souza De Paula, B; Spaan, B; Spradlin, P; Sridharan, S; Stagni, F; Stahl, M; Stahl, S; Steinkamp, O; Stenyakin, O; Sterpka, F; Stevenson, S; Stoica, S; Stone, S; Storaci, B; Stracka, S; Straticiuc, M; Straumann, U; Stroili, R; Sun, L; Sutcliffe, W; Swientek, K; Swientek, S; Syropoulos, V; Szczekowski, M; Szczypka, P; Szumlak, T; T'Jampens, S; Teklishyn, M; Tellarini, G; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Todd, J; Tolk, S; Tomassetti, L; Tonelli, D; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tresch, M; Trisovic, A; Tsaregorodtsev, A; Tsopelas, P; Tuning, N; Ubeda Garcia, M; Ukleja, A; Ustyuzhanin, A; Uwer, U; Vacca, C; Vagnoni, V; Valenti, G; Vallier, A; Vazquez Gomez, R; Vazquez Regueiro, P; Vázquez Sierra, C; Vecchi, S; Velthuis, J J; Veltri, M; Veneziano, G; Vesterinen, M; Viana Barbosa, J V V B; Viaud, B; Vieira, D; Vieites Diaz, M; Vilasis-Cardona, X; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voss, C; de Vries, J A; Waldi, R; Wallace, C; Wallace, R; Walsh, J; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Websdale, D; Whitehead, M; Wiedner, D; Wilkinson, G; Wilkinson, M; Williams, M P; Williams, M; Wilschut, H W; Wilson, F F; Wimberley, J; Wishahi, J; Wislicki, W; Witek, M; Wormser, G; Wotton, S A; Wright, S; Wyllie, K; Xie, Y; Xing, Z; Xu, Z; Yang, Z; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhokhov, A; Zhong, L

2015-02-13

Two structures are observed close to the kinematic threshold in the Ξ(b)(0)π(-) mass spectrum in a sample of proton-proton collision data, corresponding to an integrated luminosity of 3.0  fb(-1), recorded by the LHCb experiment. In the quark model, two baryonic resonances with quark content bds are expected in this mass region: the spin-parity J(P)=(1/2)(+) and J(P)=(3/2)(+) states, denoted Ξ(b)('-) and Ξ(b)(*-). Interpreting the structures as these resonances, we measure the mass differences and the width of the heavier state to be m(Ξ(b)('-))-m(Ξ(b)(0))-m(π(-))=3.653±0.018±0.006  MeV/c(2), m(Ξ(b)(*-))-m(Ξ(b)(0))-m(π(-))=23.96±0.12±0.06  MeV/c(2), Γ(Ξ(b)(*-))=1.65±0.31±0.10  MeV, where the first and second uncertainties are statistical and systematic, respectively. The width of the lighter state is consistent with zero, and we place an upper limit of Γ(Ξ(b)('-))<0.08  MeV at 95% confidence level. Relative production rates of these states are also reported.

Meson-baryon interactions in unitarized chiral perturbation theory

International Nuclear Information System (INIS)

Garcia Recio, G.; Nieves, J.; Ruiz Arriola, E.; Vicente Vacas, M.

2003-01-01

Meson-Baryon Interactions can be successfully described using both Chiral Symmetry and Unitarity. The s-wave meson-baryon scattering amplitude is analyzed in a Bethe-Salpeter coupled channel formalism incorporating Chiral Symmetry in the potential. Two body coupled channel unitarity is exactly preserved. The needed two particle irreducible matrix amplitude is taken from lowest order Chiral Perturbation Theory in a relativistic formalism. Off-shell behavior is parameterized in terms of low energy constants. The relation to the heavy baryon limit is discussed. The position of the complex poles in the second Riemann sheet of the scattering amplitude determine masses and widths baryonic resonances of the N(1535), N(1670), Λ(1405) and Λ(1670) resonances which compare well with accepted numbers

Electrons and kaons in charmed particle decays

International Nuclear Information System (INIS)

Feller, J.M.

1979-05-01

Inclusive studies of the electron content, kaon content, and associated electron-kaon content of the decays of D mesons and other charmed particles produced in electron-positron annihilation are presented. At the psi(3772) resonance the following inclusive branching ratios for D meson decays to charged kaons were measured. Also at the psi(3772) resonance the average semileptonic branching ratio for D 0 and D + decays to electrons has been measured to be .076 +- .028. The average semileptonic branching ratio of charmed particles produced in e + e - annihilation at center-of-mass energies from 3.9 to 7.4 GeV is found to be equal within errors to that of the D's. At all energies the electron momentum spectra are consistent with a combination of the decays D → Ke nu and D → K*e nu. 84 references

Strange baryons with two heavy quarks

Science.gov (United States)

Karliner, Marek; Rosner, Jonathan L.

2018-05-01

The LHCb Experiment at CERN has observed a doubly-charmed baryon Ξcc ++=c c u with a mass of 3621.40 ±0.78 MeV , consistent with many predictions. We use the same methods that led us to predict M (Ξc c,JP=1 /2+)=3627 ±12 MeV and M (Ξcc *,JP=3 /2+)=3690 ±12 MeV to predict M (Ωcc +,JP=1 /2+)=3692 ±16 MeV and M (Ωcc *,JP=3 /2+)=3756 ±16 MeV . Production and decay are discussed briefly, and predictions for M (Ωb c) and M (Ωb b) are included.

Weak decays of doubly heavy baryons. SU(3) analysis

Energy Technology Data Exchange (ETDEWEB)

Wang, Wei; Xing, Zhi-Peng; Xu, Ji [Shanghai Jiao Tong University, INPAC, Shanghai Key Laboratory for Particle Physics and Cosmology, School of Physics and Astronomy, Shanghai (China)

2017-11-15

Motivated by the recent LHCb observation of doubly charmed baryon Ξ{sub cc}{sup ++} in the Λ{sub c}{sup +}K{sup -}π{sup +}π{sup +} final state, we analyze the weak decays of doubly heavy baryons Ξ{sub cc}, Ω{sub cc}, Ξ{sub bc}, Ω{sub bc}, Ξ{sub bb} and Ω{sub bb} under the flavor SU(3) symmetry. The decay amplitudes for various semileptonic and nonleptonic decays are parametrized in terms of a few SU(3) irreducible amplitudes. We find a number of relations or sum rules between decay widths and CP asymmetries, which can be examined in future measurements at experimental facilities like LHC, Belle II and CEPC. Moreover, once a few decay branching fractions have been measured in the future, some of these relations may provide hints for exploration of new decay modes. (orig.)

Structure of hadrons. Proceedings

International Nuclear Information System (INIS)

Feldmeier, H.; Knoll, J.; Noerenberg, W.; Wambach, J.

2001-01-01

The following topics were dealt with: Hadronic reactions and resonances, structure of mesons, baryons, glueballs, and hybrids, physics with strange and charmed quarks, future projects and facilities. (HSI)

Electromagnetic dipole moments of charged baryons with bent crystals at the LHC

Energy Technology Data Exchange (ETDEWEB)

Bagli, E.; Bandiera, L.; Guidi, V.; Mazzolari, A. [Universita di Ferrara, Ferrara (Italy); INFN, Sezione di Ferrara (Italy); Cavoto, G. [' ' Sapienza' ' Universita di Roma, Rome (Italy); INFN, Sezione di Roma (Italy); Henry, L.; Martinez Vidal, F.; Ruiz Vidal, J. [IFIC, Universitat de Valencia-CSIC, Valencia (Spain); Marangotto, D. [Universita di Milano, Milan (Italy); INFN, Sezione di Milano (Italy); Merli, A.; Neri, N. [Universita di Milano, Milan (Italy); CERN, Geneva (Switzerland); INFN, Sezione di Milano (Italy)

2017-12-15

We propose a unique program of measurements of electric and magnetic dipole moments of charm, beauty and strange charged baryons at the LHC, based on the phenomenon of spin precession of channeled particles in bent crystals. Studies of crystal channeling and spin precession of positively- and negatively-charged particles are presented, along with feasibility studies and expected sensitivities for the proposed experiment using a layout based on the LHCb detector. (orig.)

Production and decay of baryonic resonances in pion induced reactions

Directory of Open Access Journals (Sweden)

Przygoda Witold

2016-01-01

Full Text Available Pion induced reactions give unique opportunities for an unambiguous description of baryonic resonances and their coupling channels. A systematic energy scan and high precision data, in conjunction with a partial wave analysis, allow for the study of the excitation function of the various contributions. A review of available world data unravels strong need for modern facilities delivering measurements with a pion beam. Recently, HADES collaboration collected data in pion-induced reactions on light (12C and heavy (74W nuclei at a beam momentum of 1.7 GeV/c dedicated to strangeness production. It was followed by a systematic scan at four different pion beam momenta (0.656, 0.69, 0.748 and 0.8 GeV/c in π− − p reaction in order to tackle the role of N(1520 resonance in conjunction with the intermediate ρ production. First results on exclusive channels with one pion (π− p and two pions (nπ+π−, pπ−π0 in the final state are discussed.

Why current algebra and PCAC are applicable for charmed-meson and -baryon weak decays

International Nuclear Information System (INIS)

Karlsen, R.E.; Scadron, M.D.

1991-01-01

By accounting for rapidly varying pole terms, the current-algebra--PCAC (partial conservation of axial-vector current) procedure properly measures large decay momentum corrections in charmed D + → bar K 0 π + , D + → bar K 0 K+, and Λ c + →p bar K 0 weak decays

Charm Decays at BABAR

International Nuclear Information System (INIS)

Charles, M.

2004-01-01

The results of several studies of charmed mesons and baryons at BABAR are presented. First, searches for the rare decays D 0 → l + l - are presented and new upper limits on these processes are established. Second, a measurement of the branching fraction of the isospin-violating hadronic decay D* s (2112) + → D s + π 0 relative to the radiative decay D* s (2112) + → D s + γ is made. Third, the decays of D* sJ (2317) + and D sJ (2460) + mesons are studied and ratios of branching fractions are measured. Fourth, Cabibbo-suppressed decays of the Λ c + are examined and their branching fractions measured relative to Cabibbo-allowed modes. Fifth, the Χ c 0 is studied through its decays to Χ - π + and (Omega) - K + ; in addition to measuring the ratio of branching fractions for Χ c 0 produced from the c(bar c) continuum, the uncorrected momentum spectrum is measured, providing clear confirmation of Χ c 0 production in B decays

Beijing: Green light for feasibility studies on tau-charm factory

International Nuclear Information System (INIS)

Anon.

1995-01-01

Full text: Since first collisions were achieved at the Beijing Institute of High Energy Physics BEPC electronpositron collider in October 1989, nine million J/psi and 1.4 million psi primes have been collected, as well as integrated luminosities of five and 23 inverse picobarns collected from respectively the tau threshold and a collision energy of 4.03 GeV. In addition, the BES spectrometer group has obtained several important tau results, including a precise measurement of the tau mass and precision studies of important tau decays. These results were a focus of interest at major meetings last summer. With many physicists across the world interested in the future of the BEPC/BES complex, in October, came the good news that the Chinese leadership had promised to support Beijing's feasibility study project for a Tau-Charm Factory (tauCF) on the BEPC site. BEPC's working energy, in the range 3 - 5.6 GeV, covers a high density region of resonances including charmonium, its excited states and production thresholds of many particles, such as the tau lepton pairs and charmed particles(mesons and baryons). The present experimental statistics and detection resolution at BEPC/ BES are not up to the task of testing the Standard Model to its limit and searching for new physics. The tauCF would be a logical continuation of BEPC/BES. With a hundred times greater luminosity and tenfold detection accuracy, tauCF could play a decisive role in ongoing physics goals. A SLAC (Stanford) workshop last summer on tauCF in the B-Factory Era underlined the importance of tauCF, with conclusion that a Bfactory cannot replace tauCF. Many scientists have observed that Beijing is one of the best places for a taucharm factory

Study of the diffractive production of baryon states and search for cryptoexotic baryons with hidden strangeness

International Nuclear Information System (INIS)

Balatz, M.Ya.; Belyaev, I.M.; Dorofeev, V.A.

1993-01-01

The reactions of baryon diffractive production p + N → (pK + K - ) + N, p + N → (pφ) + N, p + N → [Λ(1520)K + ] + N and p + N → [Σ(1385) 0 K + ] + N in the 70 GeV proton beam were studied. Very sensitive upper limits for the production cross sections of heavy narrow cryptoexotic baryon resonances with hidden strangeness were obtained

Charmonium physics at a tau-charm factory

International Nuclear Information System (INIS)

Barnes, T.; Univ. of Tennessee, Knoxville, TN

1993-01-01

Since its discovery in 1974 the charmonium system has served hadron physics as an important arena for the investigation of many aspects of QCD and hadron spectroscopy. In this summary the author briefly reviews some of these and discusses several of the important outstanding issues in hadron spectroscopy and their relation to the spectrum and couplings of resonances in the charmonium system. The topics discussed are charmonium spectroscopy, electromagnetic couplings (γ, γγ and e + e - ), strong decays and unusual states (charm molecules and charmonium hybrids), and in each case the author notes areas in which experiments at a tau-charm factory could make valuable contributions

Chiral soliton models for baryons

International Nuclear Information System (INIS)

Weigel, H.

2008-01-01

This concise research monograph introduces and reviews the concept of chiral soliton models for baryons. In these models, baryons emerge as (topological) defects of the chiral field. The many applications shed light on a number of baryon properties, ranging from static properties via nucleon resonances and deep inelastic scattering to even heavy ion collisions. As far as possible, the theoretical investigations are confronted with experiment. Conceived to bridge the gap between advanced graduate textbooks and the research literature, this volume also features a number of appendices to help nonspecialist readers to follow in more detail some of the calculations in the main text. (orig.)

Evidence for an exotic S= -2, Q= -2 baryon resonance in proton-proton collisions at the CERN SPS.

Science.gov (United States)

Alt, C; Anticic, T; Baatar, B; Barna, D; Bartke, J; Betev, L; Białkowska, H; Billmeier, A; Blume, C; Boimska, B; Botje, M; Bracinik, J; Bramm, R; Brun, R; Buncić, P; Cerny, V; Christakoglou, P; Chvala, O; Cramer, J G; Csató, P; Darmenov, N; Dimitrov, A; Dinkelaker, P; Eckardt, V; Farantatos, G; Filip, P; Flierl, D; Fodor, Z; Foka, P; Freund, P; Friese, V; Gál, J; Gaździcki, M; Georgopoulos, G; Gładysz, E; Hegyi, S; Höhne, C; Kadija, K; Karev, A; Kniege, S; Kolesnikov, V I; Kollegger, T; Korus, R; Kowalski, M; Kraus, I; Kreps, M; van Leeuwen, M; Lévai, P; Litov, L; Makariev, M; Malakhov, A I; Markert, C; Mateev, M; Mayes, B W; Melkumov, G L; Meurer, C; Mischke, A; Mitrovski, M; Molnár, J; Mrówczyński, St; Pálla, G; Panagiotou, A D; Panayotov, D; Perl, K; Petridis, A; Pikna, M; Pinsky, L; Pühlhofer, F; Reid, J G; Renfordt, R; Retyk, W; Roland, C; Roland, G; Rybczyński, M; Rybicki, A; Sandoval, A; Sann, H; Schmitz, N; Seyboth, P; Siklér, F; Sitar, B; Skrzypczak, E; Stefanek, G; Stock, R; Ströbele, H; Susa, T; Szentpétery, I; Sziklai, J; Trainor, T A; Varga, D; Vassiliou, M; Veres, G I; Vesztergombi, G; Vranić, D; Wetzler, A; Włodarczyk, Z; Yoo, I K; Zaranek, J; Zimányi, J

2004-01-30

Results of resonance searches in the Xi(-)pi(-), Xi(-)pi(+), Xi;(+)pi(-), and Xi;(+)pi(+) invariant mass spectra in proton-proton collisions at sqrt[s]=17.2 GeV are presented. Evidence is shown for the existence of a narrow Xi(-)pi(-) baryon resonance with mass of 1.862+/-0.002 GeV/c(2) and width below the detector resolution of about 0.018 GeV/c(2). The significance is estimated to be above 4.2sigma. This state is a candidate for the hypothetical exotic Xi(--)(3/2) baryon with S=-2, I=3 / 2, and a quark content of (dsdsū). At the same mass, a peak is observed in the Xi(-)pi(+) spectrum which is a candidate for the Xi(0)(3/2) member of this isospin quartet with a quark content of (dsus[-]d). The corresponding antibaryon spectra also show enhancements at the same invariant mass.

Determination of baryon and baryonic resonance masses from QCD sum rules. Strange baryons

International Nuclear Information System (INIS)

Belyaev, V.M.; Ioffe, B.L.

1982-01-01

The mass differences in baryonic octet Jsup(P)=1/2sup(+), decuplet Jsup(P)=3/2sup(+) and in octet Jsup(P)=3/2sup(-) are calculated basing on the QCD sum rules. The mass differences are expressed through two QCD parameters: the strange current qUark mass and the value of the quark condensate. At the properly chosen values of these parameters all of the mass differences are in a good agreement with experiment

Predictions for Excited Strange Baryons

Energy Technology Data Exchange (ETDEWEB)

Fernando, Ishara P.; Goity, Jose L. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

2016-04-01

An assessment is made of predictions for excited hyperon masses which follow from flavor symmetry and consistency with a 1/N c expansion of QCD. Such predictions are based on presently established baryonic resonances. Low lying hyperon resonances which do not seem to fit into the proposed scheme are discussed.

Charmed and strange baryon production in 29 GeV electron positron annihilation

International Nuclear Information System (INIS)

Klein, S.R.

1988-06-01

This dissertation presents measurements of the production rates of baryons with different strangeness and spin. The analyses presented here use data taken with the Mark III detector at the PEP storage ring, operating at a center of mass energy of 29 GeV. The Ξ/sup /minus// production rate is measured to be 0.017 +- 0.004 +- 0.004 per hadronic event, Ω/sup /minus// production is measured to be 0.014 +- 0.006 +- 0.004 per hadronic event, and Ξ* 0 production is less than 0.006 per hadronic event at a 90% confidence level. These measurements place strong constraints on models of baryon production. In particular, the unexpectedly high rate of Ω/sup /minus// production is difficult to explain in any diquark based model. Semileptonic Λ/sub c/ + decays have also been observed. Because neither the branching ratios nor the production rate are well known, it is difficult to interpret these results. However, they do indicate that the branching ratio for Λ/sub c/ + → Λlν may be higher than previous experimental measurements. 85 refs., 45 figs., 12 tabs

arXiv Electromagnetic dipole moments of charged baryons with bent crystals at the LHC

CERN Document Server

Bagli, E.; Cavoto, G.; Guidi, V.; Henry, L.; Marangotto, D.; Martinez Vidal, F.; Mazzolari, A.; Merli, A.; Neri, N.; Ruiz Vidal, J.

2017-12-05

We propose a unique program of measurements of electric and magnetic dipole moments of charm, beauty and strange charged baryons at the LHC, based on the phenomenon of spin precession of channeled particles in bent crystals. Studies of crystal channeling and spin precession of positively- and negatively-charged particles are presented, along with feasibility studies and expected sensitivities for the proposed experiment using a layout based on the LHCb detector.

Observation and study of bottom-meson decays to a charm meson, a proton-antiproton pair, and pions

Energy Technology Data Exchange (ETDEWEB)

Hong, Tae Min [Univ. of California, Santa Barbara, CA (United States)

2010-04-27

Bottom-meson decays with baryons show two unusual features—the branching fractions are enhanced for multibody decays and the baryon-antibaryon subsystem recoils against the other decay products—and their reasons are not yet well understood. Moreover, measurements using explicit reconstruction techniques constitute only about 1% out of about 8% of such decays. This Dissertation reports the study of ten bottom-meson decays (labeled 0– 9) to a proton-antiproton pair, a charm meson, and a system of up to two pions, using the BABAR Experiment’s 455×10⁶ BB pairs produced with the PEP-II asymmetric-energy e⁺e^- collider at the Stanford Linear Accelerator Center.

Study of the diffractive production of baryon states and search for cryptoexotic baryons with hidden strangeness

Energy Technology Data Exchange (ETDEWEB)

Balatz, M.Ya.; Belyaev, I.M.; Dorofeev, V.A.; Dzyubenko, G.B.; Filimonov, I.M.; Frolov, S.V.; Golovkin, S.V.; Grishkin, Yu.L.; Gritzuk, M.V.; Jilin, A.V.; Kamenskii, A.D.; Kliger, G.K.; Kolganov, V.Z.; Konstantinov, A.S.; Korchagin, Yu.V.; Kozhevnikov, A.P.; Kubarovskii, V.P.; Kulman, N.Yu.; Kulyavtsev, A.I.; Kurshetsov, V.F.; Kushnirenko, A.E.; Lakaev, V.S.; Landsberg, L.G.; Lebedev, A.A.; Lomkatzi, G.S.; Molchanov, V.V.; Mukhin, V.A.; Nilov, A.F.; Novoghilov, Yu.B.; Prutskoi, V.A.; Sitnikov, A.I.; Smolyankin, V.T.; Solyanik, V.I.; Vavilov, D.V.; Victorov, V.A.; Vishnyakov, V.E. (Inst. for High Energy Physics, Protvino (Russian Federation) Inst. of Theoretical and Experimental Physics, Moscow (Russian Federation) Moscow State Univ. (Russian Federation)); SPHINX Collaboration

1994-02-01

The reactions of baryon diffractive production p + N [yields] (pK[sup +] K[sup -]) + N, p + N [yields] (p[Phi]) + N, p + N [yields] [Lambda](1520) K[sup +] + N and p + N [yields] [Sigma](1385) K[sup +] + N in the 70 GeV proton beam were studied. Very sensitive upper limits for the production cross sections of heavy narrow cryptoexotic baryon resonances with hidden strangeness were obtained. (orig.)

Photoproduction of hermaphrodite baryons

International Nuclear Information System (INIS)

Barnes, T.; Close, F.E.

1983-02-01

It is shown that photoexcitation of the lightest hermaphrodite baryons is strongly suppressed from proton targets but allowed from neutrons, a result that is reminiscent of a quark model selection rule due to Moorhouse (Phys. Rev. Lett.; 16:772 (1966)). This is consistent with suggestions that the P 11 (1710) is the lightest q 3 G baryon and eliminates the possibility that the Roper resonance is dominantly an hermaphrodite state. Magnetic moments do not constrain the possibility of considerable mixing of q 3 G into the nucleon and delta's Fock space wavefunctions. (author)

Meson and baryon correlation studies using the PEP-TPC/2γ Facility

International Nuclear Information System (INIS)

Ronan, M.T.

1991-03-01

Results on vector meson, and strange and charmed-baryon production are presented for data taken during the period 1982--1986 using the TPC/2γ detector at PEP. Vector mesons (ρ 0 , K * and φ) with 0, 1 and 2 strange quarks are used to obtain redundant measures of strange-quark suppression and of the vector to pseudoscalar ratio in hadronization. Measurements of the production rates of Λ, Ξ - , Ω and Ξ *0 hyperons and for the Λ c and of rapidity correlations between Λ bar Λ pairs provide sensitive tests of baryon production in fragmentation models. In addition, two- and three-particle correlations between like sign pions provide further evidence for the Bose-Einstein effect in e + e - interactions including the relativistic motion of particle sources. 9 refs., 7 figs

Search for narrow four-baryon states

International Nuclear Information System (INIS)

Badelek, B.

1981-01-01

Highly excited (4.10 2 ) four-baryon resonances have been searched for in the missing-mass spectrum of the reaction π - + 4 He → π - + X at 5 GeV/c in the region of small four-momentum transfer (0.005 2 ), where one of the decay products of the X is either proton or deuteron or triton. No resonance signal is seen in the mass spectrum of X. Within our limited acceptance, the cross section for the production of a narrow (GAMMA approx. 20 MeV/c 2 ) four-baryon state with mass 4.9 GeV/c 2 is estimated to be smaller than approx. 100 nb. (orig.)

Strange b baryon production and lifetime in Z decays

Science.gov (United States)

Buskulic, D.; de Bonis, I.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Lucotte, A.; Minard, M.-N.; Nief, J.-Y.; Odier, P.; Pietrzyk, B.; Casado, M. P.; Chmeissani, M.; Crespo, J. M.; Delfino, M.; Efthymiopoulos, I.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, Ll.; Juste, A.; Martinez, M.; Orteu, S.; Padilla, C.; Park, I. C.; Pascual, A.; Perlas, J. A.; Riu, I.; Sanchez, F.; Teubert, F.; Colaleo, A.; Creanza, D.; de Palma, M.; Gelao, G.; Girone, M.; Iaselli, G.; Maggi, G.; Maggi, M.; Marinelli, N.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Alemany, R.; Bazarko, A. O.; Bonvicini, G.; Cattaneo, M.; Comas, P.; Coyle, P.; Drevermann, H.; Forty, R. W.; Frank, M.; Hagelberg, R.; Harvey, J.; Janot, P.; Jost, B.; Kneringer, E.; Knobloch, J.; Lehraus, I.; Lutters, G.; Martin, E. B.; Mato, P.; Minten, A.; Miquel, R.; Mir, Ll. M.; Moneta, L.; Oest, T.; Pacheco, A.; Pusztaszeri, J.-F.; Ranjard, F.; Rensing, P.; Rolandi, L.; Schlatter, D.; Schmelling, M.; Schmitt, M.; Schneider, O.; Tejessy, W.; Tomalin, I. R.; Venturi, A.; Wachsmuth, H.; Wagner, A.; Ajaltouni, Z.; Barrès, A.; Boyer, C.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Rosnet, P.; Rossignol, J.-M.; Fearnley, T.; Hansen, J. B.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Rensch, B.; Wäänänen, A.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Zachariadou, K.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Bourdon, P.; Rougé, A.; Rumpf, M.; Valassi, A.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Focardi, E.; Parrini, G.; Corden, M.; Georgiopoulos, C.; Jaffe, D. E.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Casper, D.; Chiarella, V.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Dorris, S. J.; Halley, A. W.; Knowles, I. G.; Lynch, J. G.; O'Shea, V.; Raine, C.; Reeves, P.; Scarr, J. M.; Smith, K.; Teixeira-Dias, P.; Thompson, A. S.; Thomson, F.; Thorn, S.; Turnbull, R. M.; Becker, U.; Geweniger, C.; Graefe, G.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E. E.; Putzer, A.; Schmidt, M.; Sommer, J.; Stenzel, H.; Tittel, K.; Werner, S.; Wunsch, M.; Abbaneo, D.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Dornan, P. J.; Moutoussi, A.; Nash, J.; Sedgbeer, J. K.; Stacey, A. M.; Williams, M. D.; Dissertori, G.; Girtler, P.; Kuhn, D.; Rudolph, G.; Betteridge, A. P.; Bowdery, C. K.; Colrain, P.; Crawford, G.; Finch, A. J.; Foster, F.; Hughes, G.; Sloan, T.; Williams, M. I.; Galla, A.; Giehl, I.; Greene, A. M.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.-G.; van Gemmeren, P.; Zeitnitz, C.; Aubert, J. J.; Bencheikh, A. M.; Benchouk, C.; Bonissent, A.; Bujosa, G.; Calvet, D.; Carr, J.; Diaconu, C.; Etienne, F.; Konstantinidis, N.; Payre, P.; Rousseau, D.; Talby, M.; Sadouki, A.; Thulasidas, M.; Trabelsi, K.; Aleppo, M.; Ragusa, F.; Abt, I.; Assmann, R.; Bauer, C.; Blum, W.; Dietl, H.; Dydak, F.; Ganis, G.; Gotzhein, C.; Jakobs, K.; Kroha, H.; Lütjens, G.; Lutz, G.; Männer, W.; Moser, H.-G.; Richter, R.; Rosado-Schlosser, A.; Schael, S.; Settles, R.; Seywerd, H.; Denis, R. St.; Wiedenmann, W.; Wolf, G.; Boucrot, J.; Callot, O.; Choi, Y.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Höcker, A.; Jacholkowska, A.; Jacquet, M.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Nikolic, I.; Park, H. J.; Schune, M.-H.; Simion, S.; Veillet, J.-J.; Videau, I.; Zerwas, D.; Azzurri, P.; Bagliesi, G.; Batignani, G.; Bettarini, S.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M. A.; Ciulli, V.; Dell'Orso, R.; Fantechi, R.; Ferrante, I.; Foà, L.; Forti, F.; Giassi, A.; Giorgi, M. A.; Gregorio, A.; Ligabue, F.; Lusiani, A.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Sciabà, A.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Vannini, C.; Verdini, P. G.; Walsh, J.; Blair, G. A.; Bryant, L. M.; Cerutti, F.; Chambers, J. T.; Gao, Y.; Green, M. G.; Medcalf, T.; Perrodo, P.; Strong, J. A.; von Wimmersperg-Toeller, J. H.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Haywood, S.; Maley, P.; Norton, P. R.; Thompson, J. C.; Wright, A. E.; Bloch-Devaux, B.; Colas, P.; Emery, S.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Marx, B.; Perez, P.; Rander, J.; Renardy, J.-F.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S. N.; Dann, J. H.; Johnson, R. P.; Kim, H. Y.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Booth, C. N.; Boswell, R.; Brew, C. A. J.; Cartwright, S.; Combley, F.; Koksal, A.; Letho, M.; Newton, W. M.; Reeve, J.; Thompson, L. F.; Böhrer, A.; Brandt, S.; Büscher, V.; Cowan, G.; Grupen, C.; Minguet-Rodriguez, J.; Rivera, F.; Saraiva, P.; Smolik, L.; Stephan, F.; Apollonio, M.; Bosisio, L.; Della Marina, R.; Giannini, G.; Gobbo, B.; Musolino, G.; Rothberg, J.; Wasserbaech, S.; Armstrong, S. R.; Elmer, P.; Feng, Z.; Ferguson, D. P. S.; Gao, Y. S.; González, S.; Grahl, J.; Greening, T. C.; Hayes, O. J.; Hu, H.; McNamara, P. A.; Nachtman, J. M.; Orejudos, W.; Pan, Y. B.; Saadi, Y.; Scott, I. J.; Walsh, A. M.; Wu, Sau Lan; Wu, X.; Yamartino, J. M.; Zheng, M.; Zobernig, G.; Aleph Collaboration

1996-02-01

In a data sample of approximately four million hadronic Z decays recorded with the ALEPH detector from 1990 to 1995, a search for the strange b baryon Ξb is performed with a study of Ξ-lepton correlations. Forty-four events with same sign Ξ-ℓ - combinations are found whereas 8.4 are expected based on the rate of opposite sign Ξ-ℓ + combinations. This significant excess is interpreted as evidence for Ξb semileptonic decays. The measured product branching ratio is Br(b → Ξ b) × Br(Ξ b → X cXℓ -overlineν ℓ) × Br(X c → Ξ -X‧) = (5.4±1.1(stat) ± 0.8(syst)) × 10 -4 per lepton species, averaged over electrons and muons, with X c a charmed baryon. The Ξb lifetime is measured to be τΞb = 1.35 -0.28+0.37(stat) -0.17+0.15(syst) ps.

The semileptonic baryonic decay Ds+ → p p bar e+νe

Science.gov (United States)

Cheng, Hai-Yang; Kang, Xian-Wei

2018-05-01

The decay Ds+ → p p bar e+νe with a proton-antiproton pair in the final state is unique in the sense that it is the only semileptonic baryonic decay which is physically allowed in the charmed meson sector. Its measurement will test our basic knowledge on semileptonic Ds+ decays and the low-energy p p bar interactions. Taking into account the major intermediate state contributions from η ,η‧ ,f0 (980) and X (1835), we find that its branching fraction is at the level of 10-9 ∼10-8. The location and the nature of X (1835) state are crucial for the precise determination of the branching fraction. We wish to trigger a new round of a careful study with the upcoming more data in BESIII as well as the future super tau-charm factory.

Hadronic decay properties of newly observed $\\Omega_c$ baryons

OpenAIRE

Zhao, Ze; Ye, Dan-Dan; Zhang, Ailin

2017-01-01

Hadronic decay widths of the newly observed charmed strange baryons, $\\Omega_c(3000)^0$, $\\Omega_c(3050)^0$, $\\Omega_c(3066)^0$, $\\Omega_c(3090)^0$ and $\\Omega_c(3119)^0$ have been calculated in a $^3P_0$ model. Our results indicate that $\\Omega_c(3066)^0$ and $\\Omega_c(3090)^0$ can be interpreted as the $1P-$wave $\\Omega_{c2}(\\frac{3}{2}^-)$ or $\\Omega_{c2}(\\frac{5}{2}^-)$. Though the measured masses of $\\Omega_c(3000)^0$, $\\Omega_c(3050)^0$ and $\\Omega_c(3119)^0$ are lower than existed theo...

Hadron spectroscopy in LHCb

CERN Document Server

Palano, Antimo

2018-01-01

The LHCb experiment is designed to study the properties and decays of heavy flavored hadrons produced in pp collisions at the LHC. The data collected in the LHC Run I enables precision spectroscopy studies of beauty and charm hadrons. The latest results on spectroscopy of conventional and exotic hadrons are reviewed. In particular the discovery of the first charmonium pentaquark states in the $J/\\psi p$ system, the possible existence of four-quark states decaying to $J/\\psi \\phi$ and the confirmation of resonant nature of the $Z_c(4430)^−$ mesonic state are discussed. In the sector of charmed baryons, the observation of five new $\\Omega_c$ states, the observation of the $\\Xi^+_{cc}$ and the study of charmed baryons decaying to $D^0 p$ are presented.

Charmed and strange baryon production in 29 GeV electron positron annihilation

Energy Technology Data Exchange (ETDEWEB)

Klein, S.R.

1988-06-01

This dissertation presents measurements of the production rates of baryons with different strangeness and spin. The analyses presented here use data taken with the Mark III detector at the PEP storage ring, operating at a center of mass energy of 29 GeV. The ..xi../sup /minus// production rate is measured to be 0.017 +- 0.004 +- 0.004 per hadronic event, ..cap omega../sup /minus// production is measured to be 0.014 +- 0.006 +- 0.004 per hadronic event, and ..xi..*/sup 0/ production is less than 0.006 per hadronic event at a 90% confidence level. These measurements place strong constraints on models of baryon production. In particular, the unexpectedly high rate of ..cap omega../sup /minus// production is difficult to explain in any diquark based model. Semileptonic ..lambda../sub c//sup +/ decays have also been observed. Because neither the branching ratios nor the production rate are well known, it is difficult to interpret these results. However, they do indicate that the branching ratio for ..lambda../sub c//sup +/ ..-->.. ..lambda..l..nu.. may be higher than previous experimental measurements. 85 refs., 45 figs., 12 tabs.

Observation of the Cabibbo-suppressed charmed baryon decay Λc+→pφ

International Nuclear Information System (INIS)

Alexander, J.P.; Bebek, C.; Berger, B.E.; Berkelman, K.; Bloom, K.; Browder, T.E.; Cassel, D.G.; Cho, H.A.; Coffman, D.M.; Crowcroft, D.S.; Dickson, M.; Drell, P.S.; Dumas, D.J.; Ehrlich, R.; Elia, R.; Gaidarev, P.; Garcia-Sciveres, M.; Gittelman, B.; Gray, S.W.; Hartill, D.L.; Heltsley, B.K.; Henderson, S.; Jones, C.D.; Jones, S.L.; Kandaswamy, J.; Katayama, N.; Kim, P.C.; Kreinick, D.L.; Lee, T.; Liu, Y.; Ludwig, G.S.; Masui, J.; Mevissen, J.; Mistry, N.B.; Ng, C.R.; Nordberg, E.; Patterson, J.R.; Peterson, D.; Riley, D.; Soffer, A.; Avery, P.; Freyberger, A.; Lingel, K.; Prescott, C.; Rodriguez, J.; Yang, S.; Yelton, J.; Brandenburg, G.; Cinabro, D.; Liu, T.; Saulnier, M.; Wilson, R.; Yamamoto, H.; Bergfeld, T.; Eisenstein, B.I.; Ernst, J.; Gladding, G.E.; Gollin, G.D.; Palmer, M.; Selen, M.; Thaler, J.J.; Edwards, K.W.; McLean, K.W.; Ogg, M.; Bellerive, A.; Britton, D.I.; Hyatt, E.R.; Janicek, R.; MacFarlane, D.B.; Patel, P.M.; Spaan, B.; Sadoff, A.J.; Ammar, R.; Baringer, P.; Bean, A.; Besson, D.; Coppage, D.; Copty, N.; Davis, R.; Hancock, N.; Kotov, S.; Kravchenko, I.; Kwak, N.; Kubota, Y.; Lattery, M.; Momayezi, M.; Nelson, J.K.; Patton, S.; Poling, R.; Savinov, V.; Schrenk, S.; Wang, R.; Alam, M.S.; Kim, I.J.; Ling, Z.; Mahmood, A.H.; ONeill, J.J.; Severini, H.; Sun, C.R.; Wappler, F.; Crawford, G.; Fulton, R.; Fujino, D.; Gan, K.K.; Honscheid, K.; Kagan, H.; Kass, R.; Lee, J.; Sung, M.; White, C.; Wolf, A.; Zoeller, M.M.; Fu, X.; Nemati, B.; Ross, W.R.; Skubic, P.; Wood, M.; Bishai, M.; Fast, J.; Gerndt, E.; Hinson, J.W.; Miao, T.; Miller, D.H.; Modesitt, M.; Shibata, E.I.; Shipsey, I.P.; Wang, P.N.; Gibbons, L.; Johnson, S.D.; Kwon, Y.; Roberts, S.; Thorndike, E.H.; Coan, T.E.; Dominick, J.; Fadeyev, V.; Korolkov, I.; Lambrecht, M.; Sanghera, S.; Shelkov, V.; Skwarnicki, T.; Stroynowski, R.; Volobouev, I.; Wei, G.; Artuso, M.; Gao, M.; Goldberg, M.; He, D.; Horwitz, N.; Kopp, S.; Moneti, G.C.; Mountain, R.; Muheim, F.; Mukhin, Y.; Playfer, S.

1996-01-01

We report the observation of the Cabibbo-suppressed decays Λ c + →pK - K + and Λ c + →pφ using data collected with the CLEO II detector at CESR. The latter mode, observed for the first time with significant statistics, is of interest as a test of color suppression in charm decays. We have determined the branching ratios for these modes relative to Λ c + →pK - π + and compared our results with theory. copyright 1996 The American Physical Society

Mass spectra of hidden-charm molecular pentaquarks states

International Nuclear Information System (INIS)

Patel, Smruti; Vinodkumar, P.C.

2016-01-01

Very recently, the LHCb Collaboration has reported two hidden-charmed resonances P_c(4380) and P_c(4450) consistent with pentaquark states in the Λ_b"0 → K"-J/Ψp process with masses (widths) (4380 ±8 ± 29) MeV ((205 ±18 ± 86) MeV) and (4449.8 ±1.7 ± 2.5) MeV ((39 ±5 ±19) MeV), respectively. The observation of the P_c states has aroused the theorist's strong interest in the hidden-charm pentaquark states. They have been studied in various frameworks, such as the molecule-like pentaquark states, the diquark-diquark-antiquark type pentaquark states, the diquark-triquark type pentaquark states, re-scattering effects, etc. An identification of pentaquark states as exotic hadron has been one of the long standing problems in the physics of strong interaction and quantum chromodynamics (QCD). A decade ago lots of discussion were made about pentaquarks states but due to lack of further experimental evidences the study of pentaquarks have been almost gone in the darkness. But, recent remarkable observation of two resonances i.e. P_c(4380) and P_c(4450) with hidden charm and the minimal quark content cc-baruud provided new impact for studies of pentaquark states and opens a new window to study the exotic hadronic matter

Thermal relaxation of charm in hadronic matter

Energy Technology Data Exchange (ETDEWEB)

He Min, E-mail: mhe@comp.tamu.edu [Cyclotron Institute and Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); Fries, Rainer J. [Cyclotron Institute and Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); RIKEN/BNL Research Center, Brookhaven National Laboratory, Upton, NY 11973 (United States); Rapp, Ralf [Cyclotron Institute and Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States)

2011-07-18

The thermal relaxation rate of open-charm (D) mesons in hot and dense hadronic matter is calculated using empirical elastic scattering amplitudes. D-meson interactions with thermal pions are approximated by D{sup *} resonances, while scattering off other hadrons (K, {eta}, {rho}, {omega}, K{sup *}, N, {Delta}) is evaluated using vacuum scattering amplitudes as available in the literature based on effective Lagrangians and constrained by realistic spectroscopy. The thermal relaxation time of D-mesons in a hot {pi} gas is found to be around 25-50 fm/c for temperatures T=150-180 MeV, which reduces to 10-25 fm/c in a hadron-resonance gas. The latter values, argued to be conservative estimates, imply significant modifications of D-meson spectra in heavy-ion collisions. Close to the critical temperature (T{sub c}), the spatial diffusion coefficient (D{sub s}) is surprisingly similar to recent calculations for charm quarks in the Quark-Gluon Plasma using non-perturbative T-matrix interactions. This suggests a possibly continuous minimum structure of D{sub s} around T{sub c}.

QCD in heavy quark production and decay

Energy Technology Data Exchange (ETDEWEB)

Wiss, J. [Univ. of Illinois, Urbana, IL (United States)

1997-06-01

The author discusses how QCD is used to understand the physics of heavy quark production and decay dynamics. His discussion of production dynamics primarily concentrates on charm photoproduction data which are compared to perturbative QCD calculations which incorporate fragmentation effects. He begins his discussion of heavy quark decay by reviewing data on charm and beauty lifetimes. Present data on fully leptonic and semileptonic charm decay are then reviewed. Measurements of the hadronic weak current form factors are compared to the nonperturbative QCD-based predictions of Lattice Gauge Theories. He next discusses polarization phenomena present in charmed baryon decay. Heavy Quark Effective Theory predicts that the daughter baryon will recoil from the charmed parent with nearly 100% left-handed polarization, which is in excellent agreement with present data. He concludes by discussing nonleptonic charm decay which is traditionally analyzed in a factorization framework applicable to two-body and quasi-two-body nonleptonic decays. This discussion emphasizes the important role of final state interactions in influencing both the observed decay width of various two-body final states as well as modifying the interference between interfering resonance channels which contribute to specific multibody decays. 50 refs., 77 figs.

QCD in heavy quark production and decay

International Nuclear Information System (INIS)

Wiss, J.

1997-01-01

The author discusses how QCD is used to understand the physics of heavy quark production and decay dynamics. His discussion of production dynamics primarily concentrates on charm photoproduction data which are compared to perturbative QCD calculations which incorporate fragmentation effects. He begins his discussion of heavy quark decay by reviewing data on charm and beauty lifetimes. Present data on fully leptonic and semileptonic charm decay are then reviewed. Measurements of the hadronic weak current form factors are compared to the nonperturbative QCD-based predictions of Lattice Gauge Theories. He next discusses polarization phenomena present in charmed baryon decay. Heavy Quark Effective Theory predicts that the daughter baryon will recoil from the charmed parent with nearly 100% left-handed polarization, which is in excellent agreement with present data. He concludes by discussing nonleptonic charm decay which is traditionally analyzed in a factorization framework applicable to two-body and quasi-two-body nonleptonic decays. This discussion emphasizes the important role of final state interactions in influencing both the observed decay width of various two-body final states as well as modifying the interference between interfering resonance channels which contribute to specific multibody decays. 50 refs., 77 figs

Double-charming Higgs boson identification using machine-learning assisted jet shapes

Science.gov (United States)

Lenz, Alexander; Spannowsky, Michael; Tetlalmatzi-Xolocotzi, Gilberto

2018-01-01

We study the possibility of identifying a boosted resonance that decays into a charm pair against different sources of background using QCD event shapes, which are promoted to jet shapes. Using a set of jet shapes as input to a boosted decision tree, we find that observables utilizing the simultaneous presence of two charm quarks can access complementary information compared to approaches relying on two independent charm tags. Focusing on Higgs associated production with subsequent H →c c ¯ decay and on a C P -odd scalar A with mA≤10 GeV we obtain the limits B r (H →c c ¯ )≤6.48 % and B r (H →A (→c c ¯ )Z )≤0.01 % at 95% C.L.

Polarization in pp → p(baryon)

International Nuclear Information System (INIS)

Castillo-Vallejo, Victor M.; Felix, Julian

2003-01-01

It's introduced a calculation, which is based on symmetries followed by high energy hadronic interactions, of resonance polarization and specific angular momentum state polarization created in pp → p(baryon)

Negative parity non-strange baryons

International Nuclear Information System (INIS)

Stancu, F.; Stassart, P.

1991-01-01

Our previous study is extended to negative parity baryon resonances up to J=(9/2) - . The framework is a semi-relativistic constituent quark model. The quark-quark interaction contains a Coulomb plus linear confinement terms and a short distance spin-spin and tensor terms. It is emphasized that a linear confinement potential gives too large a mass to the D 35 (1930) resonance. (orig.)

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)

How sensitive are di-leptons from ρ mesons to the high baryon density region?

International Nuclear Information System (INIS)

Vogel, S.; Schmidt, K.; Santini, E.; Sturm, C.; Bleicher, M.; Petersen, H.; Aichelin, J.

2008-01-01

We show that the measurement of dileptons might provide only a restricted view into the most dense stages of heavy-ion reactions. Thus, possible studies of meson and baryon properties at high baryon densities, as, e.g., done at the GSI High Acceptance DiElectron Spectrometer (HADES) and envisioned for the Facility for Antiproton and Ion Research (FAIR) compressed baryonic matter experiments, might observe weaker effects than currently expected in certain approaches. We argue that the strong absorption of resonances in the high-baryon-density region of the heavy-ion collision masks information from the early hot and dense phase due to a strong increase of the total decay width because of collisional broadening. To obtain additional information, we also compare the currently used approaches to extract dileptons from transport simulations, i.e., shining, only vector mesons from final baryon resonance decays and instant emission of dileptons and find a strong sensitivity on the method employed in particular at FAIR and the CERN Super Proton Synchrotron energies. It is shown explicitly that a restriction to ρ meson (and therefore dilepton) production only in final-state baryon resonance decays provide a strong bias toward rather low baryon densities. The results presented are obtained from ultrarelativistic quantum molecular dynamics v2.3 calculations using the standard setup

Baryon spectroscopy and SU(6)

International Nuclear Information System (INIS)

Litchfield, P.

1977-09-01

An elementary account of the SU(6) formalism for baryons is given. The assignment of the known resonances to SU(6) multiplets is discussed and an experimental scheme given for the spectrum of SU(6) x 0(2) multiplets. (author)

Baryon states with open charm in the extended local hidden gauge approach

Energy Technology Data Exchange (ETDEWEB)

Liang, W.H. [Guangxi Normal University, Department of Physics, Guilin (China); Uchino, T.; Xiao, C.W.; Oset, E. [Centro Mixto Universidad de Valencia-CSIC, Institutos de Investigacion de Paterna, Departamento de Fisica Teorica, Valencia (Spain); IFIC, Valencia (Spain)

2015-02-01

In this paper we examine the interaction of DN and D* N states, together with their coupled channels, by using an extension of the local hidden gauge formalism from the light meson sector, which is based on heavy quark spin symmetry. The scheme is based on the use of the impulse approximation at the quark level, with the heavy quarks acting as spectators, which occurs for the dominant terms where there is the exchange of a light meson. The pion exchange and the Weinberg-Tomozawa interactions are generalized and with this dynamics we look for states generated from the interaction, with a unitary coupled channels approach that mixes the pseudoscalar-baryon and vector-baryon states. We find two states with nearly zero width, which are associated to the Λ{sub c} (2595) and Λ{sub c} (2625). The lower state, with J{sup P} = 1/2{sup -}, couples to DN and D* N, and the second one, with J{sup P} = 3/2{sup -}, to D* N. In addition to these two Λ{sub c} states, we find four more states with I = 0, one of them nearly degenerate in two states of J{sup P} = 1/2, 3/2. Furthermore we find three states in I = 1, two of them degenerate in J = 1/2, 3/2. (orig.)

Production of excited charm and charm-strange mesons at HERA

International Nuclear Information System (INIS)

Chekanov, S.; Derrick, M.; Magill, S.; Musgrave, B.; Nicholass, D.; Repond, J.; Yoshida, R.; Mattingly, M.C.K.; Antonioli, P.; Bari, G.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Cindolo, F.; Corradi, M.; Iacobucci, G.; Margotti, A.; Nania, R.; Polini, A.; Antonelli, S.; Basile, M.; Bindi, M.; Cifarelli, L.; Contin, A.; De Pasquale, S.; Sartorelli, G.; Zichichi, A.; Bartsch, D.; Brock, I.; Hartmann, H.; Hilger, E.; Jakob, H.P.; Juengst, M.; Nuncio-Quiroz, A.E.; Paul, E.; Samson, U.; Schoenberg, V.; Shehzadi, R.; Wlasenko, M.; Brook, N.H.; Heath, G.P.; Morris, J.D.; Capua, M.; Fazio, S.; Mastroberardino, A.; Schioppa, M.; Susinno, G.; Tassi, E.; Kim, J.Y.; Ibrahim, Z.A.; Kamaluddin, B.; Wan Abdullah, W.A.T.; Ning, Y.; Ren, Z.; Sciulli, F.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Galas, A.; Gil, M.; Olkiewicz, K.; Stopa, P.; Zawiejski, L.; Adamczyk, L.; Bold, T.; Grabowska-Bold, I.; Kisielewska, D.; Lukasik, J.; Przybycien, M.; Suszycki, L.; Kotanski, A.; Slominski, W.; Behrens, U.; Blohm, C.; Bonato, A.; Borras, K.; Ciesielski, R.; Coppola, N.; Fang, S.; Fourletova, J.; Geiser, A.; Goettlicher, P.; Grebenyuk, J.; Gregor, I.; Haas, T.; Hain, W.; Huettmann, A.; Januschek, F.; Kahle, B.; Katkov, I.I.; Klein, U.; Koetz, U.; Kowalski, H.; Lobodzinska, E.; Loehr, B.; Mankel, R.; Melzer-Pellmann, I.A.; Miglioranzi, S.; Montanari, A.; Namsoo, T.; Notz, D.; Parenti, A.; Rinaldi, L.; Roloff, P.; Rubinsky, I.; Santamarta, R.; Schneekloth, U.; Spiridonov, A.; Szuba, D.; Szuba, J.; Theedt, T.; Wolf, G.; Wrona, K.; Yaguees Molina, A.G.; Youngman, C.; Zeuner, W.; Drugakov, V.; Lohmann, W.; Schlenstedt, S.; Barbagli, G.; Gallo, E.; Pelfer, P.G.; Bamberger, A.; Dobur, D.; Karstens, F.; Vlasov, N.N.; Bussey, P.J.; Doyle, A.T.; Dunne, W.; Forrest, M.; Rosin, M.; Saxon, D.H.; Skillicorn, I.O.; Gialas, I.; Papageorgiu, K.; Holm, U.; Klanner, R.; Lohrmann, E.; Schleper, P.; Schoerner-Sadenius, T.; Sztuk, J.; Stadie, H.; Turcato, M.; Foudas, C.; Fry, C.; Long, K.R.; Tapper, A.D.; Matsumoto, T.; Nagano, K.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Barakbaev, A.N.; Boos, E.G.; Pokrovskiy, N.S.; Zhautykov, B.O.; Aushev, V.; Bachynska, O.; Borodin, M.; Kadenko, I.; Kozulia, A.; Libov, V.; Lisovyi, M.; Lontkovskyi, D.; Makarenko, I.; Sorokin, I.; Verbytskyi, A.; Volynets, O.; Son, D.; Favereau, J. de; Piotrzkowski, K.; Barreiro, F.; Glasman, C.; Jimenez, M.; Labarga, L.; Peso, J. del; Ron, E.; Soares, M.; Terron, J.; Zambrana, M.; Corriveau, F.; Liu, C.; Schwartz, J.; Walsh, R.; Zhou, C.; Tsurugai, T.; Antonov, A.; Dolgoshein, B.A.; Gladkov, D.; Sosnovtsev, V.; Stifutkin, A.; Suchkov, S.; Dementiev, R.K.; Ermolov, P.F.; Gladilin, L.K.; Golubkov, Yu.A.; Khein, L.A.; Korzhavina, I.A.; Kuzmin, V.A.; Levchenko, B.B.; Lukina, O.Yu.; Proskuryakov, A.S.; Shcheglova, L.M.; Zotkin, D.S.; Abt, I.; Caldwell, A.; Kollar, D.; Reisert, B.; Schmidke, W.B.; Grigorescu, G.; Keramidas, A.; Koffeman, E.; Kooijman, P.; Pellegrino, A.; Tiecke, H.; Vazquez, M.; Wiggers, L.; Bruemmer, N.; Bylsma, B.; Durkin, L.S.; Lee, A.; Ling, T.Y.; Allfrey, P.D.; Bell, M.A.; Cooper-Sarkar, A.M.; Devenish, R.C.E.; Ferrando, J.; Foster, B.; Korcsak-Gorzo, K.; Oliver, K.; Robertson, A.; Uribe-Estrada, C.; Walczak, R.; Bertolin, A.; Dal Corso, F.; Dusini, S.; Longhin, A.; Stanco, L.; Bellan, P.; Brugnera, R.; Carlin, R.; Garfagnini, A.; Limentani, S.; Oh, B.Y.; Raval, A.; Ukleja, J.; Whitmore, J.J.; Iga, Y.; D'Agostini, G.; Marini, G.; Nigro, A.; Cole, J.E.; Hart, J.C.

2009-01-01

The production of excited charm, D 1 (2420) 0 and D 2 * (2460) 0 , and charm-strange, D s 1(2536) ± , mesons in ep collisions was measured with the ZEUS detector at HERA using an integrated luminosity of 126 pb -1 . Masses, widths and helicity parameters were determined. The measured yields were converted to the rates of c quarks hadronising as a given excited charm meson and to the ratios of the dominant D 2 * (2460) 0 and D s1 (2536) ± branching fractions. A search for the radially excited charm meson, D *' (2640) ± , was also performed. The results are compared with those measured previously and with theoretical expectations. (orig.)

Production of excited charm and charm-strange mesons at HERA

International Nuclear Information System (INIS)

Chekanov, S.; Derrick, M.; Magill, S.

2008-07-01

The production of excited charm, D 1 (2420) 0 and D * 2 (2460) 0 , and charm-strange, D s1 (2536) ± , mesons in ep collisions was measured with the ZEUS detector at HERA using an integrated luminosity of 126 pb -1 . Masses, widths and helicity parameters were determined. The measured yields were converted to the rates of c quarks hadronising as a given excited charm meson and to the ratios of the dominant D * 2 (2460) 0 and D s1 (2536) ± branching fractions. A search for the radially excited charm meson, D *' (2640) ± , was also performed. The results are compared with those measured previously and with theoretical expectations. (orig.)

Study of a possible S=+1 dynamically generated baryonic resonance

International Nuclear Information System (INIS)

Sarkar, S.; Oset, E.; Vaca, M.J.V.

2005-01-01

Starting from the lowest-order chiral Lagrangian for the interaction of the baryon decuplet with the octet of pseudoscalar mesons we find an attractive interaction in the ΔK channel with L=0 and I=1, while the interaction is repulsive for I=2. The attractive interaction leads to a pole in the second Riemann sheet of the complex plane and manifests itself in a large strength of the K scattering amplitude close to the ΔK threshold, which is not the case for I=2. However, we also make a study of uncertainties in the model and conclude that the existence of this pole depends sensitively upon the input used and can disappear within reasonable variations of the input parameters. We take advantage to study the stability of the other poles obtained for the 3/2 - dynamically generated resonances of the model and conclude that they are stable and not contingent to reasonable changes in the input of the theory

Production of excited charm and charm-strange mesons at HERA

Energy Technology Data Exchange (ETDEWEB)

Chekanov, S.; Derrick, M.; Magill, S. [Argonne National Laboratory, Argonne, IL (US)] (and others)

2008-07-15

The production of excited charm, D{sub 1}(2420){sup 0} and D{sup *}{sub 2}(2460){sup 0}, and charm-strange, D{sub s1}(2536){sup {+-}}, mesons in ep collisions was measured with the ZEUS detector at HERA using an integrated luminosity of 126 pb{sup -1}. Masses, widths and helicity parameters were determined. The measured yields were converted to the rates of c quarks hadronising as a given excited charm meson and to the ratios of the dominant D{sup *}{sub 2}(2460){sup 0} and D{sub s1}(2536){sup {+-}} branching fractions. A search for the radially excited charm meson, D{sup *'}(2640){sup {+-}}, was also performed. The results are compared with those measured previously and with theoretical expectations. (orig.)

Derivation of sum rules for quark and baryon fields

International Nuclear Information System (INIS)

Bongardt, K.

1978-01-01

In an analogous way to the Weinberg sum rules, two spectral-function sum rules for quark and baryon fields are derived by means of the concept of lightlike charges. The baryon sum rules are valid for the case of SU 3 as well as for SU 4 and the one-particle approximation yields a linear mass relation. This relation is not in disagreement with the normal linear GMO formula for the baryons. The calculated masses of the first resonance states agree very well with the experimental data

Brane-induced Skyrmion on S3: Baryonic matter in holographic QCD

International Nuclear Information System (INIS)

Nawa, Kanabu; Suganuma, Hideo; Kojo, Toru

2009-01-01

We study baryonic matter in holographic QCD with D4/D8/D8 multi-D brane system in type IIA superstring theory. The baryon is described as the 'brane-induced Skyrmion', which is a topologically nontrivial chiral soliton in the four-dimensional meson effective action induced by holographic QCD. We employ the ''truncated-resonance model'' approach for the baryon analysis, including pion and ρ meson fields below the ultraviolet cutoff scale M KK ∼1 GeV, to keep the holographic duality with QCD. We describe the baryonic matter in large N c as single brane-induced Skyrmion on the three-dimensional closed manifold S 3 with finite radius R. The interactions between baryons are simulated by the curvature of the closed manifold S 3 , and the decrease of the size of S 3 represents the increase of the total baryon-number density in the medium in this modeling. We investigate the energy density, the field configuration, the mass and the root-mean-square radius of single baryon on S 3 as the function of its radius R. We find a new picture of 'pion dominance' near the critical density in the baryonic matter, where all the (axial) vector meson fields disappear and only the pion fields survive. We also find the swelling phenomena of the baryons as the precursor of the deconfinement, and propose the mechanism of the swelling in the general context of QCD. The properties of the deconfinement and the chiral symmetry restoration in the baryonic matter are examined by taking the proper order parameters. We also compare our truncated-resonance model with another instanton description of the baryon in holographic QCD, considering the role of cutoff scale M KK .

$\\mathrm{\\Lambda_{c}^{+}}$ baryon production measurements with the ALICE experiment at the LHC

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00416828; Dainton, John; Lemmon, Roy

Quantum chromodynamics, the quantum field theory that describes the strong interaction, demonstrates a property known as asymptotic freedom which weakens the strong coupling constant $\\alpha_s$ at high energies or short distances. The measurement of particles containing heavy quarks, i.e. charm and beauty, in high-energy particle collisions is a stringent test of the theory of quantum chromodynamics in the regime where $\\alpha_s$ is small. In addition, asymptotic freedom leads to a phase transition of nuclear matter at high temperatures or energy densities to a phase known as the Quark-Gluon Plasma, where quarks and gluons are deconfined, and this state of matter can be studied in relativistic heavy-ion collisions. Particles containing heavy quarks, i.e. charm and beauty, have been proposed as probes of the properties of the Quark Gluon Plasma, where the measurement of mesons and baryons can offer insight into the transport properties of the medium and mechanisms related to the formation of hadrons during the...

Charm quark mass with calibrated uncertainty

Energy Technology Data Exchange (ETDEWEB)

Erler, Jens [Universidad Nacional Autonoma de Mexico, Instituto de Fisica, Mexico, DF (Mexico); Masjuan, Pere [Universitat Autonoma de Barcelona, Grup de Fisica Teorica, Departament de Fisica, Barcelona (Spain); Institut de Fisica d' Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), Barcelona (Spain); Spiesberger, Hubert [Johannes Gutenberg-Universitaet, PRISMA Cluster of Excellence, Institut fuer Physik, Mainz (Germany); University of Cape Town, Centre for Theoretical and Mathematical Physics and Department of Physics, Rondebosch (South Africa)

2017-02-15

We determine the charm quark mass m{sub c} from QCD sum rules of the moments of the vector current correlator calculated in perturbative QCD at O(α{sub s}{sup 3}). Only experimental data for the charm resonances below the continuum threshold are needed in our approach, while the continuum contribution is determined by requiring self-consistency between various sum rules, including the one for the zeroth moment. Existing data from the continuum region can then be used to bound the theoretic uncertainty. Our result is m{sub c}(m{sub c}) = 1272 ± 8 MeV for α{sub s}(M{sub Z}) = 0.1182, where the central value is in very good agreement with other recent determinations based on the relativistic sum rule approach. On the other hand, there is considerably less agreement regarding the theory dominated uncertainty and we pay special attention to the question how to quantify and justify it. (orig.)

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)

Highlights from STAR

International Nuclear Information System (INIS)

Schweda, Kai

2004-01-01

Selected results from the STAR collaboration are presented. We focus on recent results on jet-like correlations, nuclear modification factors of identified hadrons, elliptic flow of multi-strange baryons Ξ and Ω, and resonance yields. First measurements of open charm production at RHIC are presented

Strangeness as a probe to baryon-rich QCD matter at NICA

Energy Technology Data Exchange (ETDEWEB)

Fukushima, Kenji [The University of Tokyo, Department of Physics, Bunkyo-ku, Tokyo (Japan)

2016-08-15

We elucidate a prospect of strangeness fluctuation measurements in the heavy-ion collision at NICA energies. The strangeness fluctuation is sensitive to quark deconfinement. At the same time strangeness has a strong correlation with the baryon number under the condition of vanishing net strangeness, which leads to an enhancement of Λ{sup 0}, Ξ{sup 0}, Ξ{sup -}, and K{sup +} at high baryon density. The baryon density is maximized around the NICA energies, and strangeness should be an ideal probe to investigate quark deconfinement phenomena of baryon-rich QCD matter created at NICA. We also utilize the hadron resonance gas model to estimate a mixed fluctuation of strangeness and baryon number. (orig.)

On the hidden charm pentaquarks in Λ{sub b} → J/ψK{sup -} p decay

Energy Technology Data Exchange (ETDEWEB)

Roca, L. [Universidad de Murcia, Departamento de Fisica, Murcia (Spain); Oset, E. [Centro Mixto Universidad de Valencia-CSIC Institutos de Investigacion de Paterna, Departamento de Fisica Teorica y IFIC, Valencia (Spain)

2016-11-15

In a previous work we presented a theoretical analysis of the Λ{sub b} → J/ψK{sup -} p reaction based on which a recent experiment by the LHCb collaboration at CERN claimed the existence of two hidden charm pentaquarks, P{sub c}(4380){sup +} and P{sub c}(4450){sup +}. In that work we focused only on the Λ(1405) and P{sub c}(4450){sup +} signals and discussed the possible explanation of this pentaquark state within the picture of a dynamical meson-baryon molecule made up mostly from anti D*Σ{sub c} and anti D*Σ{sup *}{sub c} components. In the present work we improve upon the previous one by considering the total K{sup -} p and J/ψp data including all the relevant resonances contributing to the spectra, and discuss the possible nature of both P{sub c}(4380){sup +} and P{sub c}(4450){sup +}. We also discuss several important topics, like the effect of the contact term in the reaction, the viability of reproducing the data without the P{sub c}(4380){sup +} and the possible quantum number assignment to these pentaquarks. (orig.)

Charmed meson production at LHCb

International Nuclear Information System (INIS)

Müller, Dominik

2016-01-01

Measurements of charm meson production are important tests for QCD predictions and LHCb is uniquely suited to perform these measurements in the forward region. This paper summarises recent charm meson production measurements performed by LHCb of J/ψ and open charm mesons and the associated production of ϒ and open charm mesons. The J/ψ and open charm meson measurements are performed with data recorded in Run 2 of the Large Hadron Collider. With proton-proton collisions at √s = 13 TeV, these open a new regime in which QCD predictions for charm meson production may be precisely tested. Furthermore, ratios of cross-sections at different centre-of-mass energies benefit of cancellation of both experimental and theoretical uncertainties, providing a new sensitive test of the QCD calculations. Measurements of ϒ and open charm meson associated production are performed using √s = 7 TeV and √s = 8 TeV data and constitute the first observation of this production channel.

The search for exotic baryons at the HERMES experiment

International Nuclear Information System (INIS)

Deconinck, Wouter

2008-07-01

One of the interesting questions of Quantum Chromodynamics, the theory that governs the interactions between quarks and gluons, has been whether it is possible to observe hadrons which can not be explained as a combination of only two or three valence quarks. In numerous searches the existence of these exotic hadrons could not be confirmed. Recently, calculations based on the quark soliton model predicted the narrow exotic baryons Θ + and Ξ -- . A narrow resonance identified as the Θ + was observed by several experiments at the predicted mass of 1540 MeV, but later followed by several dedicated experiments that could not confirm these positive results. At the HERMES experiment a search for the quasi-real photoproduction of the exotic baryon Θ + on a deuterium target and the subsequent decay through pK 0 S → pπ + π - revealed a narrow resonance in the pK 0 S invariant mass distribution at 1528 MeV. In the search for the corresponding antiparticle Ξ -- the result is consistent with zero events. In this thesis we present the search for the exotic baryon Ξ -- on a deuterium target in the data sample used for the observation of the Θ + . An upper limit on the cross section of the exotic baryon Ξ -- is determined. The search for the exotic baryon Θ + on hydrogen and deuterium targets at the HERMES experiment is extensively discussed. The event mixing method can be used to estimate the distribution of background events. Several difficulties with this method were addressed, but the background description in the case of the exotic baryon Θ + remains unconvincing. Between the years 2002 and 2005 the HERMES experiment operated with a magnetic holding field around the hydrogen target. A method for the reconstruction of displaced vertices in this field was developed. The data collected during the years 2006 and 2007 offer an integrated luminosity that is several times higher than in previous data sets. After investigating all data sets collected with the HERMES

Reanalysis of the EMC charm production data with extrinsic and intrinsic charm at NLO

International Nuclear Information System (INIS)

Harris, B.W.; Vogt, R.

1996-01-01

A calculation of the next-to-leading order exclusive extrinsic charm quark differential distributions in deeply inelastic electroproduction has recently been completed. Using these results we compare the NLO extrinsic contributions to the charm structure function F 2 (x,Q 2 ,m c 2 ) with the corresponding NLO intrinsic contributions. The results of this analysis are compared with the EMC DIS charm quark data and evidence for an intrinsic charm component in the proton is found. (orig.)

The compressed baryonic matter experiment at FAIR

International Nuclear Information System (INIS)

Senger, Peter

2015-01-01

Substantial experimental and theoretical efforts worldwide are devoted to explore the phase diagram of strongly interacting matter. At top RHIC and LHC energies, the QCD phase diagram is studied at very high temperatures and very low net-baryon densities. These conditions presumably existed in the early universe about a microsecond after the big bang. For larger net-baryon densities and lower temperatures, it is expected that the QCD phase diagram exhibits a rich structure such as a critical point, a first order phase transition between hadronic and partonic matter, or new phases like quarkyonic matter. The experimental discovery of these prominent landmarks of the QCD phase diagram would be a major breakthrough in our understanding of the properties of nuclear matter. The Compressed Baryonic Matter (CBM) experiment will be one of the major scientific pillars of the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt. The goal of the CBM research program is to explore the QCD phase diagram in the region of high baryon densities using high-energy nucleus-nucleus collisions. This includes the study of the equation-of-state of nuclear matter at neutron star core densities, and the search for the deconfinement and chiral phase transitions. The CBM detector is designed to measure rare diagnostic probes such as multi-strange hyperons, charmed particles and vector mesons decaying into lepton pairs with unprecedented precision and statistics. Most of these particles will be studied for the first time in the FAIR energy range. In order to achieve the required precision, the measurements will be performed at very high reaction rates of 100 kHz to 10 MHz. This requires very fast and radiation-hard detectors, and a novel data read-out and analysis concept based on free streaming front-end electronics and a high-performance computing cluster for online event selection. The layout, the physics performance, and the status of the proposed CBM experimental facility

The tau-charm factory: Experimental perspectives

International Nuclear Information System (INIS)

Perl, M.L.; Schindler, R.H.

1991-09-01

This report discusses the Tau-Charm Factory Concept; D and D S Physics at the Tau-Charm Factory; τ and ν τ Physics at the Tau-Charm Factory; and Charmonium, Gluonium and Light Quark Spectroscopy at the Tau-Charm Factory

Repulsive baryonic interactions and lattice QCD observables at imaginary chemical potential

Directory of Open Access Journals (Sweden)

Volodymyr Vovchenko

2017-12-01

Full Text Available The first principle lattice QCD methods allow to calculate the thermodynamic observables at finite temperature and imaginary chemical potential. These can be compared to the predictions of various phenomenological models. We argue that Fourier coefficients with respect to imaginary baryochemical potential are sensitive to modeling of baryonic interactions. As a first application of this sensitivity, we consider the hadron resonance gas (HRG model with repulsive baryonic interactions, which are modeled by means of the excluded volume correction. The Fourier coefficients of the imaginary part of the net-baryon density at imaginary baryochemical potential – corresponding to the fugacity or virial expansion at real chemical potential – are calculated within this model, and compared with the Nt=12 lattice data. The lattice QCD behavior of the first four Fourier coefficients up to T≃185 MeV is described fairly well by an interacting HRG with a single baryon–baryon eigenvolume interaction parameter b≃1 fm3, while the available lattice data on the difference χ2B−χ4B of baryon number susceptibilities is reproduced up to T≃175 MeV. Keywords: Hadron resonance gas, Excluded volume, Imaginary chemical potential

Excited charmed mesons

International Nuclear Information System (INIS)

Butler, J.N.; Shukla, S.

1995-05-01

The experimental status of excited charmed mesons is reviewed and is compared to theoretical expectations. Six states have been observed and their properties are consistent with those predicted for excited charmed states with orbital angular momentum equal to one

Tau-charm factory..

Energy Technology Data Exchange (ETDEWEB)

Anon.

1995-10-15

In addition to hearing the latest experimental and theoretical developments at the 17th International Symposium on Lepton Photon Interactions in Beijing, delegates were brought up-to-date on the substantial progress towards the realization of a Tau-Charm Factory in the Chinese capital. Opening the Symposium, Zhou Guangzhao, President of the Chinese Academy of Sciences, expressed a commitment of the Chinese government to basic research and its interest in the continuing development high energy physics in China. Following the very successful construction and operation of Beijing's Electron-Positron Collider, BEPC, the Chinese government has provided 5M yuan ($US 600,000) for a feasibility study by the end of 1996 for a Tau-Charm Factory at Beijing's Institute of High Energy Physics (IHEP). Professor Zhou expressed his belief that, once approved, such a factory would greatly enhance high energy physics in China. He warmly welcomed international collaboration both in the construction of the accelerator and in the experimental programme. His comments were reinforced in the following welcome speech by IHEP Director Zheng Zhipeng. Conference delegates had the opportunity to inspect the BEPC injector and collider, built almost entirely by Chinese industry. The International Committee for Future Accelerators (ICFA) met during the Symposium, with Tau- Charm Factory business on the agenda. In his subsequent report, ICFA Chairman John Peoples said that a Tau-Charm Factory provides a unique experimental environment for the precision studies of tau, charm and light quark-gluon spectroscopy, and that some issues in these fields are not satisfactorily addressed solely by B Factories or fixed-target experiments. The committee expressed a strong interest in seeing a Tau-Charm Factory built and noted the serious interest, especially in China, and looks forward to operation and exploitation by the international physics community. In their Beijing summary talks, both Sam Ting and T

Tau-charm factory..

International Nuclear Information System (INIS)

Anon.

1995-01-01

In addition to hearing the latest experimental and theoretical developments at the 17th International Symposium on Lepton Photon Interactions in Beijing, delegates were brought up-to-date on the substantial progress towards the realization of a Tau-Charm Factory in the Chinese capital. Opening the Symposium, Zhou Guangzhao, President of the Chinese Academy of Sciences, expressed a commitment of the Chinese government to basic research and its interest in the continuing development high energy physics in China. Following the very successful construction and operation of Beijing's Electron-Positron Collider, BEPC, the Chinese government has provided 5M yuan ($US 600,000) for a feasibility study by the end of 1996 for a Tau-Charm Factory at Beijing's Institute of High Energy Physics (IHEP). Professor Zhou expressed his belief that, once approved, such a factory would greatly enhance high energy physics in China. He warmly welcomed international collaboration both in the construction of the accelerator and in the experimental programme. His comments were reinforced in the following welcome speech by IHEP Director Zheng Zhipeng. Conference delegates had the opportunity to inspect the BEPC injector and collider, built almost entirely by Chinese industry. The International Committee for Future Accelerators (ICFA) met during the Symposium, with Tau- Charm Factory business on the agenda. In his subsequent report, ICFA Chairman John Peoples said that a Tau-Charm Factory provides a unique experimental environment for the precision studies of tau, charm and light quark-gluon spectroscopy, and that some issues in these fields are not satisfactorily addressed solely by B Factories or fixed-target experiments. The committee expressed a strong interest in seeing a Tau-Charm Factory built and noted the serious interest, especially in China, and looks forward to operation and exploitation by the international physics community. In their Beijing summary talks, both Sam Ting

...tau and charm

International Nuclear Information System (INIS)

Anon.

1993-01-01

The Standard Model of particle physics has six quarks, grouped in three pairs (up/down, charm/strange, top/beauty), each pair being partnered with a lepton and its corresponding neutrino - respectively electron, muon, and tau. Probing the Standard Model in depth to see what makes it work means peering into all quark/lepton corners. While B physics, with its potential at proton and electron-positron machines, is being pushed hard (see previous article), other physicists underline the need for complementary information from other sectors. Essential experimental tools for exploring out-of-the-ordinary particles are a Tau-Charm Factory and a Beauty Factory. These machines address similar basic questions in the Standard Model, but in complementary ways: the Beauty Factory is optimized for beauty particles and CP violation in B decays; and the TCF is optimized for the tau lepton, charm particles, and the spectroscopy of hidden charm states and light hadrons. In early June about 100 physicists - theorists, experimentalists and accelerator physicists - from Europe and beyond gathered in Marbella, Spain, for the 3rd Workshop on the Tau-Charm Factory (TCF). The workshop aimed to reassess the TCF physics potential in the light of recent progress, to develop further the designs of the machine and the detector, and to discuss the experimental programme

CP violation in charm and other recent charm results from LHCb

CERN Document Server

Rademacker, Jonas

2012-01-01

The LHCb experiment has accumulated an unprecedented sample of charm data. In these proceedings we present measurements of CP violation and rare in charm in LHCb data accu­ mulated in 2010 and 2011. Many of these measurements are the most precise today.

Baryon asymmetry, dark matter and local baryon number

International Nuclear Information System (INIS)

Fileviez Pérez, Pavel; Patel, Hiren H.

2014-01-01

We propose a new mechanism to understand the relation between baryon and dark matter asymmetries in the universe in theories where the baryon number is a local symmetry. In these scenarios the B−L asymmetry generated through a mechanism such as leptogenesis is transferred to the dark matter and baryonic sectors through sphalerons processes which conserve total baryon number. We show that it is possible to have a consistent relation between the dark matter relic density and the baryon asymmetry in the universe even if the baryon number is broken at the low scale through the Higgs mechanism. We also discuss the case where one uses the Stueckelberg mechanism to understand the conservation of baryon number in nature.

High pT charm photoproduction

International Nuclear Information System (INIS)

Abbiendi, G.; Butterworth, J.M.

1996-09-01

The expected rates for charm-tagged jet photoproduction are evaluated for a number of tagging procedures, and some of the physics potential is discussed. Charm in jets is tagged using D * 's, μ's, or tracks from secondary vertices which might be identified in a microvertex detector. We find high expected event rates, leading to the possibility of placing strong constraints on the kinematics of charm production and on the gluon content of the proton and the charm content of the photon. (orig.)

Baryonic and Non-Baryonic Dark Matter

OpenAIRE

Carr, Bernard

2000-01-01

Cosmological nucleosynthesis calculations imply that there should be both non-baryonic and baryonic dark matter. Recent data suggest that some of the non-baryonic dark matter must be "hot" (i.e. massive neutrinos) and there may also be evidence for "cold" dark matter (i.e. WIMPs). If the baryonic dark matter resides in galactic halos, it is likely to be in the form of compact objects (i.e. MACHOs) and these would probably be the remnants of a first generation of pregalactic or protogalactic P...

The mass spectrum of double heavy baryons in new potential quark models

Directory of Open Access Journals (Sweden)

Kovalenko Vladimir

2017-01-01

Full Text Available A new approach to study the mass spectrum of double heavy baryons (QQ′q containing strange and charmed quarks is proposed. It is based on the separation of variables in the Schrodinger equation in the prolate spheroidal coordinates. Two nonrelativistic potential models are considered. In the first model, the interaction potential of the quarks is the sum of the Coulomb and non-spherically symmetrical linear confinement potential. In the second model it is assumed that the quark confinement provided by a spherically symmetric harmonic oscillator potential. In both models the mass spectrum is calculated, and a comparison with previous results from other models is performed.

Charm production yield from target nuclei filtering intrinsic projectile charm

International Nuclear Information System (INIS)

Quack, E.; Nemes, M.C.

1990-01-01

Estimating the process of filtering an intrinsic projectile charm component by a target nucleus as proposed earlier, we obtain upper limits for the cross sections of open charm and J/Ψ. Comparing with experiment, we conclude that this filtering mechanism is not sufficient to explain the observed A α-dependence at large final state momenta. (author)

The search for exotic baryons at the HERMES experiment

Energy Technology Data Exchange (ETDEWEB)

Deconinck, Wouter

2008-07-15

One of the interesting questions of Quantum Chromodynamics, the theory that governs the interactions between quarks and gluons, has been whether it is possible to observe hadrons which can not be explained as a combination of only two or three valence quarks. In numerous searches the existence of these exotic hadrons could not be confirmed. Recently, calculations based on the quark soliton model predicted the narrow exotic baryons {theta}{sup +} and {xi}{sup --}. A narrow resonance identified as the {theta}{sup +} was observed by several experiments at the predicted mass of 1540 MeV, but later followed by several dedicated experiments that could not confirm these positive results. At the HERMES experiment a search for the quasi-real photoproduction of the exotic baryon {theta}{sup +} on a deuterium target and the subsequent decay through pK{sup 0}{sub S} {yields} p{pi}{sup +}{pi}{sup -} revealed a narrow resonance in the pK{sup 0}{sub S} invariant mass distribution at 1528 MeV. In the search for the corresponding antiparticle {xi}{sup --} the result is consistent with zero events. In this thesis we present the search for the exotic baryon {xi}{sup --} on a deuterium target in the data sample used for the observation of the {theta}{sup +}. An upper limit on the cross section of the exotic baryon {xi}{sup --} is determined. The search for the exotic baryon {theta}{sup +} on hydrogen and deuterium targets at the HERMES experiment is extensively discussed. The event mixing method can be used to estimate the distribution of background events. Several difficulties with this method were addressed, but the background description in the case of the exotic baryon {theta}{sup +} remains unconvincing. Between the years 2002 and 2005 the HERMES experiment operated with a magnetic holding field around the hydrogen target. A method for the reconstruction of displaced vertices in this field was developed. The data collected during the years 2006 and 2007 offer an integrated

Spontaneous violation of chiral symmetry in QCD vacuum is the origin of baryon masses and determines baryon magnetic moments and their other static properties

International Nuclear Information System (INIS)

Ioffe, B. L.

2009-01-01

A short review is presented of the spontaneous violation of chiral symmetry in QCD vacuum. It is demonstrated that this phenomenon is the origin of baryon masses in QCD. The value of nucleon mass is calculated, as well as the masses of hyperons and some baryonic resonances, and expressed mainly through the values of quark condensates - , q = u, d, s,-the vacuum expectation values (v.e.v.) of quark field. The concept of v.e.v. induced by external fields is introduced. It is demonstrated that such v.e.v. induced by static electromagnetic field results in quark condensate magnetic susceptibility, which plays the main role in determination of baryon magnetic moments. The magnetic moments of proton, neutron, and hyperons are calculated. The results of calculation of baryon octet β-decay constants are also presented.

Searches for Rare or Forbidden Semileptonic Charm Decays

International Nuclear Information System (INIS)

Lees, J.P.

2011-01-01

We present searches for rare or forbidden charm decays of the form X c + → h ± (ell) ± (ell) (# prime# )+ , where X c + is a charm hardron (D + , D s + , or Λ c + ), h ± is a pion, kaon, or proton, and (ell) (# prime# )± is an electron or muon. The analysis is based on 384 fb -1 of e + e - annihilation data collected at or close to the Υ(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signal is observed for any of the 35 decay modes that are investigated. We establish 90% confidence-level upper limits on the branching fractions between 1 x 10 -6 and 44 x 10 -6 depending on the channel. In most cases, these results represent either the first limits or significant improvements on existing limits for the decay modes studied.

On the phase strucutre of baryonic matter

International Nuclear Information System (INIS)

Heide, E.; Ellis, P.J.

1991-01-01

We have studied the phase structure of baryonic matter in a model which includes nucleons and delta resonances interacting with σ- and ω-mesons. In the mean-field approximation, the existence of phase transitions to delta matter and to a baryon-antibaryon plasma was strongly dependent on the values chosen for the equilibrium effective mass and compression modulus. When vacuum fluctuations were included, the physically acceptable solutions only yielded a liquid-gas phase transition. Further, these solutions were restricted to rather large values of the effective mass and compression modulus which did not include the currently accepted values. (orig.)

Charmed meson production and decay properties at the psi(3770)

Energy Technology Data Exchange (ETDEWEB)

1979-05-01

A remeasurement of the resonance near E/sub cm/ = 3.77 GeV in the e/sup +/e/sup -/ annihilation is presented. The properties of the resonance are used to deduce branching fractions of charmed mesons into hadronic final states. Several previously unseen decay modes are reported. Decays into Cabibbo suppressed final states are observed. The inclusive properties of D meson decays are studied, including strangeness and charged particle multiplicity. The semileptonic branching fractions for D/sup 0/ and D/sup -+/ are measured, providing a determination of the relative lifetimes of these particles.

Charmed meson production and decay properties at the psi(3770)

International Nuclear Information System (INIS)

1979-05-01

A remeasurement of the resonance near E/sub cm/ = 3.77 GeV in the e + e - annihilation is presented. The properties of the resonance are used to deduce branching fractions of charmed mesons into hadronic final states. Several previously unseen decay modes are reported. Decays into Cabibbo suppressed final states are observed. The inclusive properties of D meson decays are studied, including strangeness and charged particle multiplicity. The semileptonic branching fractions for D 0 and D/sup -+/ are measured, providing a determination of the relative lifetimes of these particles

Search for Baryon-Number Violating Ξ_{b}^{0} Oscillations.

Science.gov (United States)

Aaij, R; Adeva, B; Adinolfi, M; Ajaltouni, Z; Akar, S; Albrecht, J; Alessio, F; Alexander, M; Alfonso Albero, A; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amerio, S; Amhis, Y; An, L; Anderlini, L; Andreassi, G; Andreotti, M; Andrews, J E; Appleby, R B; Archilli, F; d'Argent, P; Arnau Romeu, J; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Baalouch, M; Babuschkin, I; Bachmann, S; Back, J J; Badalov, A; Baesso, C; Baker, S; Balagura, V; Baldini, W; Baranov, A; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Baryshnikov, F; Batozskaya, V; Battista, V; Bay, A; Beaucourt, L; Beddow, J; Bedeschi, F; Bediaga, I; Beiter, A; Bel, L J; Beliy, N; Bellee, V; Belloli, N; Belous, K; Belyaev, I; Ben-Haim, E; Bencivenni, G; Benson, S; Beranek, S; Berezhnoy, A; Bernet, R; Berninghoff, D; Bertholet, E; Bertolin, A; Betancourt, C; Betti, F; Bettler, M-O; van Beuzekom, M; Bezshyiko, Ia; Bifani, S; Billoir, P; Birnkraut, A; Bitadze, A; Bizzeti, A; Bjørn, M; Blake, T; Blanc, F; Blouw, J; Blusk, S; Bocci, V; Boettcher, T; Bondar, A; Bondar, N; Bonivento, W; Bordyuzhin, I; Borgheresi, A; Borghi, S; Borisyak, M; Borsato, M; Bossu, F; Boubdir, M; Bowcock, T J V; Bowen, E; Bozzi, C; Braun, S; Britton, T; Brodzicka, J; Brundu, D; Buchanan, E; Burr, C; Bursche, A; Buytaert, J; Byczynski, W; Cadeddu, S; Cai, H; Calabrese, R; Calladine, R; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Campora Perez, D H; Capriotti, L; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carniti, P; Carson, L; Carvalho Akiba, K; Casse, G; Cassina, L; Castillo Garcia, L; Cattaneo, M; Cavallero, G; Cenci, R; Chamont, D; Charles, M; Charpentier, Ph; Chatzikonstantinidis, G; Chefdeville, M; Chen, S; Cheung, S F; Chitic, S-G; Chobanova, V; Chrzaszcz, M; Chubykin, A; Ciambrone, P; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Cogan, J; Cogneras, E; Cogoni, V; Cojocariu, L; Collins, P; Colombo, T; Comerma-Montells, A; Contu, A; Cook, A; Coombs, G; Coquereau, S; Corti, G; Corvo, M; Costa Sobral, C M; Couturier, B; Cowan, G A; Craik, D C; Crocombe, A; Cruz Torres, M; Currie, R; D'Ambrosio, C; Da Cunha Marinho, F; Dall'Occo, E; Dalseno, J; Davis, A; De Aguiar Francisco, O; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Serio, M; De Simone, P; Dean, C T; Decamp, D; Del Buono, L; Dembinski, H-P; Demmer, M; Dendek, A; Derkach, D; Deschamps, O; Dettori, F; Dey, B; Di Canto, A; Di Nezza, P; Dijkstra, H; Dordei, F; Dorigo, M; Dosil Suárez, A; Douglas, L; Dovbnya, A; Dreimanis, K; Dufour, L; Dujany, G; Durante, P; Dzhelyadin, R; Dziewiecki, M; Dziurda, A; Dzyuba, A; Easo, S; Ebert, M; Egede, U; Egorychev, V; Eidelman, S; Eisenhardt, S; Eitschberger, U; Ekelhof, R; Eklund, L; Ely, S; Esen, S; Evans, H M; Evans, T; Falabella, A; Farley, N; Farry, S; Fazzini, D; Federici, L; Ferguson, D; Fernandez, G; Fernandez Declara, P; Fernandez Prieto, A; Ferrari, F; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fini, R A; Fiore, M; Fiorini, M; Firlej, M; Fitzpatrick, C; Fiutowski, T; Fleuret, F; Fohl, K; Fontana, M; Fontanelli, F; Forshaw, D C; Forty, R; Franco Lima, V; Frank, M; Frei, C; Fu, J; Funk, W; Furfaro, E; Färber, C; Gabriel, E; Gallas Torreira, A; Galli, D; Gallorini, S; Gambetta, S; Gandelman, M; Gandini, P; Gao, Y; Garcia Martin, L M; García Pardiñas, J; Garra Tico, J; Garrido, L; Garsed, P J; Gascon, D; Gaspar, C; Gavardi, L; Gazzoni, G; Gerick, D; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gianì, S; Gibson, V; Girard, O G; Giubega, L; Gizdov, K; Gligorov, V V; Golubkov, D; Golutvin, A; Gomes, A; Gorelov, I V; Gotti, C; Govorkova, E; Grabowski, J P; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graverini, E; Graziani, G; Grecu, A; Greim, R; Griffith, P; Grillo, L; Gruber, L; Gruberg Cazon, B R; Grünberg, O; Gushchin, E; Guz, Yu; Gys, T; Göbel, C; Hadavizadeh, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hamilton, B; Han, X; Hancock, T H; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Hasse, C; Hatch, M; He, J; Hecker, M; Heinicke, K; Heister, A; Hennessy, K; Henrard, P; Henry, L; van Herwijnen, E; Heß, M; Hicheur, A; Hill, D; Hombach, C; Hopchev, P H; Huard, Z C; Hulsbergen, W; Humair, T; Hushchyn, M; Hutchcroft, D; Ibis, P; Idzik, M; Ilten, P; Jacobsson, R; Jalocha, J; Jans, E; Jawahery, A; Jiang, F; John, M; Johnson, D; Jones, C R; Joram, C; Jost, B; Jurik, N; Kandybei, S; Karacson, M; Kariuki, J M; Karodia, S; Kazeev, N; Kecke, M; Kelsey, M; Kenzie, M; Ketel, T; Khairullin, E; Khanji, B; Khurewathanakul, C; Kirn, T; Klaver, S; Klimaszewski, K; Klimkovich, T; Koliiev, S; Kolpin, M; Komarov, I; Kopecna, R; Koppenburg, P; Kosmyntseva, A; Kotriakhova, S; Kozeiha, M; Kravchuk, L; Kreps, M; Krokovny, P; Kruse, F; Krzemien, W; Kucewicz, W; Kucharczyk, M; Kudryavtsev, V; Kuonen, A K; Kurek, K; Kvaratskheliya, T; Lacarrere, D; Lafferty, G; Lai, A; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; Leflat, A; Lefrançois, J; Lefèvre, R; Lemaitre, F; Lemos Cid, E; Leroy, O; Lesiak, T; Leverington, B; Li, P-R; Li, T; Li, Y; Li, Z; Likhomanenko, T; Lindner, R; Lionetto, F; Lisovskyi, V; Liu, X; Loh, D; Loi, A; Longstaff, I; Lopes, J H; Lucchesi, D; Lucio Martinez, M; Luo, H; Lupato, A; Luppi, E; Lupton, O; Lusiani, A; Lyu, X; Machefert, F; Maciuc, F; Macko, V; Mackowiak, P; Maddrell-Mander, S; Maev, O; Maguire, K; Maisuzenko, D; Majewski, M W; Malde, S; Malinin, A; Maltsev, T; Manca, G; Mancinelli, G; Manning, P; Marangotto, D; Maratas, J; Marchand, J F; Marconi, U; Marin Benito, C; Marinangeli, M; Marino, P; Marks, J; Martellotti, G; Martin, M; Martinelli, M; Martinez Santos, D; Martinez Vidal, F; Martins Tostes, D; Massacrier, L M; Massafferri, A; Matev, R; Mathad, A; Mathe, Z; Matteuzzi, C; Mauri, A; Maurice, E; Maurin, B; Mazurov, A; McCann, M; McNab, A; McNulty, R; Mead, J V; Meadows, B; Meaux, C; Meier, F; Meinert, N; Melnychuk, D; Merk, M; Merli, A; Michielin, E; Milanes, D A; Millard, E; Minard, M-N; Minzoni, L; Mitzel, D S; Mogini, A; Molina Rodriguez, J; Mombacher, T; Monroy, I A; Monteil, S; Morandin, M; Morello, M J; Morgunova, O; Moron, J; Morris, A B; Mountain, R; Muheim, F; Mulder, M; Müller, D; Müller, J; Müller, K; Müller, V; Naik, P; Nakada, T; Nandakumar, R; Nandi, A; Nasteva, I; Needham, M; Neri, N; Neubert, S; Neufeld, N; Neuner, M; Nguyen, T D; Nguyen-Mau, C; Nieswand, S; Niet, R; Nikitin, N; Nikodem, T; Nogay, A; O'Hanlon, D P; Oblakowska-Mucha, A; Obraztsov, V; Ogilvy, S; Oldeman, R; Onderwater, C J G; Ossowska, A; Otalora Goicochea, J M; Owen, P; Oyanguren, A; Pais, P R; Palano, A; Palutan, M; Papanestis, A; Pappagallo, M; Pappalardo, L L; Parker, W; Parkes, C; Passaleva, G; Pastore, A; Patel, M; Patrignani, C; Pearce, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perret, P; Pescatore, L; Petridis, K; Petrolini, A; Petrov, A; Petruzzo, M; Picatoste Olloqui, E; Pietrzyk, B; Pikies, M; Pinci, D; Pistone, A; Piucci, A; Placinta, V; Playfer, S; Plo Casasus, M; Polci, F; Poli Lener, M; Poluektov, A; Polyakov, I; Polycarpo, E; Pomery, G J; Ponce, S; Popov, A; Popov, D; Poslavskii, S; Potterat, C; Price, E; Prisciandaro, J; Prouve, C; Pugatch, V; Puig Navarro, A; Pullen, H; Punzi, G; Qian, W; Quagliani, R; Quintana, B; Rachwal, B; Rademacker, J H; Rama, M; Ramos Pernas, M; Rangel, M S; Raniuk, I; Ratnikov, F; Raven, G; Ravonel Salzgeber, M; Reboud, M; Redi, F; Reichert, S; Dos Reis, A C; Remon Alepuz, C; Renaudin, V; Ricciardi, S; Richards, S; Rihl, M; Rinnert, K; Rives Molina, V; Robbe, P; Robert, A; Rodrigues, A B; Rodrigues, E; Rodriguez Lopez, J A; Rodriguez Perez, P; Rogozhnikov, A; Roiser, S; Rollings, A; Romanovskiy, V; Romero Vidal, A; Ronayne, J W; Rotondo, M; Rudolph, M S; Ruf, T; Ruiz Valls, P; Ruiz Vidal, J; Saborido Silva, J J; Sadykhov, E; Sagidova, N; Saitta, B; Salustino Guimaraes, V; Sanchez Mayordomo, C; Sanmartin Sedes, B; Santacesaria, R; Santamarina Rios, C; Santimaria, M; Santovetti, E; Sarpis, G; Sarti, A; Satriano, C; Satta, A; Saunders, D M; Savrina, D; Schael, S; Schellenberg, M; Schiller, M; Schindler, H; Schlupp, M; Schmelling, M; Schmelzer, T; Schmidt, B; Schneider, O; Schopper, A; Schreiner, H F; Schubert, K; Schubiger, M; Schune, M-H; Schwemmer, R; Sciascia, B; Sciubba, A; Semennikov, A; Sepulveda, E S; Sergi, A; Serra, N; Serrano, J; Sestini, L; Seyfert, P; Shapkin, M; Shapoval, I; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, V; Siddi, B G; Silva Coutinho, R; Silva de Oliveira, L; Simi, G; Simone, S; Sirendi, M; Skidmore, N; Skwarnicki, T; Smith, E; Smith, I T; Smith, J; Smith, M; Soares Lavra, L; Sokoloff, M D; Soler, F J P; Souza De Paula, B; Spaan, B; Spradlin, P; Sridharan, S; Stagni, F; Stahl, M; Stahl, S; Stefko, P; Stefkova, S; Steinkamp, O; Stemmle, S; Stenyakin, O; Stepanova, M; Stevens, H; Stone, S; Storaci, B; Stracka, S; Stramaglia, M E; Straticiuc, M; Straumann, U; Sun, J; Sun, L; Sutcliffe, W; Swientek, K; Syropoulos, V; Szczekowski, M; Szumlak, T; Szymanski, M; T'Jampens, S; Tayduganov, A; Tekampe, T; Tellarini, G; Teubert, F; Thomas, E; van Tilburg, J; Tilley, M J; Tisserand, V; Tobin, M; Tolk, S; Tomassetti, L; Tonelli, D; Toriello, F; Tourinho Jadallah Aoude, R; Tournefier, E; Traill, M; Tran, M T; Tresch, M; Trisovic, A; Tsaregorodtsev, A; Tsopelas, P; Tully, A; Tuning, N; Ukleja, A; Usachov, A; Ustyuzhanin, A; Uwer, U; Vacca, C; Vagner, A; Vagnoni, V; Valassi, A; Valat, S; Valenti, G; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; van Veghel, M; Velthuis, J J; Veltri, M; Veneziano, G; Venkateswaran, A; Verlage, T A; Vernet, M; Vesterinen, M; Viana Barbosa, J V; Viaud, B; Vieira, D; Vieites Diaz, M; Viemann, H; Vilasis-Cardona, X; Vitti, M; Volkov, V; Vollhardt, A; Voneki, B; Vorobyev, A; Vorobyev, V; Voß, C; de Vries, J A; Vázquez Sierra, C; Waldi, R; Wallace, C; Wallace, R; Walsh, J; Wang, J; Ward, D R; Wark, H M; Watson, N K; Websdale, D; Weiden, A; Whitehead, M; Wicht, J; Wilkinson, G; Wilkinson, M; Williams, M; Williams, M P; Williams, M; Williams, T; Wilson, F F; Wimberley, J; Winn, M; Wishahi, J; Wislicki, W; Witek, M; Wormser, G; Wotton, S A; Wraight, K; Wyllie, K; Xie, Y; Xu, Z; Yang, Z; Yang, Z; Yao, Y; Yin, H; Yu, J; Yuan, X; Yushchenko, O; Zarebski, K A; Zavertyaev, M; Zhang, L; Zhang, Y; Zhelezov, A; Zheng, Y; Zhu, X; Zhukov, V; Zonneveld, J B; Zucchelli, S

2017-11-03

A search for baryon-number violating Ξ_{b}^{0} oscillations is performed with a sample of pp collision data recorded by the LHCb experiment, corresponding to an integrated luminosity of 3  fb^{-1}. The baryon number at the moment of production is identified by requiring that the Ξ_{b}^{0} come from the decay of a resonance Ξ_{b}^{*-}→Ξ_{b}^{0}π^{-} or Ξ_{b}^{'-}→Ξ_{b}^{0}π^{-}, and the baryon number at the moment of decay is identified from the final state using the decays Ξ_{b}^{0}→Ξ_{c}^{+}π^{-},Ξ_{c}^{+}→pK^{-}π^{+}. No evidence of baryon-number violation is found, and an upper limit at the 95% confidence level is set on the oscillation rate of ω<0.08  ps^{-1}, where ω is the associated angular frequency.

Study of ψ(3770 decaying to baryon anti-baryon pairs

Directory of Open Access Journals (Sweden)

Li-Gang Xia

2016-05-01

Full Text Available To study the decays of ψ(3770 going to baryon anti-baryon pairs (BB¯, all available experiments of measuring the cross sections of e+e−→BB¯ at center-of-mass energy ranging from 3.0 GeV to 3.9 GeV are combined. To relate the baryon octets, a model based on the SU(3 flavor symmetry is used and the SU(3 breaking effects are also considered. Assuming the electric and magnetic form factors are equal (|GE|=|GM|, a global fit including the interference between the QED process and the resonant process is performed. The branching fraction of ψ(3770→BB¯ is determined to be (2.4±0.8±0.3×10−5, (1.7±0.6±0.1×10−5, (4.5±0.9±0.1×10−5, (4.5±0.9±0.1×10−5, (2.0±0.7±0.1×10−5, and (2.0±0.7±0.1×10−5 for B=p,Λ,Σ+,Σ0,Ξ− and Ξ0, respectively, where the first uncertainty is from the global fit and the second uncertainty is the systematic uncertainty due to the assumption |GE|=|GM|. They are at least one order of magnitude larger than a simple scaling of the branching fraction of J/ψ/ψ(3686→BB¯.

Charming surprise

CERN Multimedia

Antonella Del Rosso

2011-01-01

The CP violation in charm quarks has always been thought to be extremely small. So, looking at particle decays involving matter and antimatter, the LHCb experiment has recently been surprised to observe that things might be different. Theorists are on the case.   The study of the physics of the charm quark was not in the initial plans of the LHCb experiment, whose letter “b” stands for “beauty quark”. However, already one year ago, the Collaboration decided to look into a wider spectrum of processes that involve charm quarks among other things. The LHCb trigger allows a lot of these processes to be selected, and, among them, one has recently shown interesting features. Other experiments at b-factories have already performed the same measurement but this is the first time that it has been possible to achieve such high precision, thanks to the huge amount of data provided by the very high luminosity of the LHC. “We have observed the decay modes of t...

Charm searches - status of the art

International Nuclear Information System (INIS)

Reay, N.W.

1984-01-01

In this talk I will concentrate on a few topics associated with measuring charm lifetimes, search for new charm states and measuring inclusive charm production cross-sections. The intent is not to have universal coverage, but rather to give a feeling for the world's progress (or lack of it) in studying charm. Finally, I'll close with a few dreams for the future which were presented at the workshop preceding this conference

Study of Rare Charm Decays with the LHCb Detector at CERN

CERN Document Server

Kochebina, Olga

Rare charm decays proceed mostly through the $c\\rightarrow u$ Flavor Changing Neutral Current (FCNC), which is possible only at loop level in the Standard Model (SM). In charmed decays, FCNCs are subject to a very efficient GIM suppression leading to very rare processes. Consequently, rare charm decays are good tools to probe New Physics (NP) beyond the SM. NP particles could become detectable by causing observables such as branching ratios and CP or angular asymmetries to deviate from the SM predictions. The main subject of this thesis is the measurement of the branching ratio of the $D^{0}\\rightarrow K^{-}\\pi^{+}\\rho/\\omega(\\rightarrow\\mu^{+}\\mu^{-})$, the partial branching ratio of the of the $D^{0}\\rightarrow K^{-}\\pi^{+}\\mu^{+}\\mu^{-}$ mode, in the region of the $m(\\mu^{+}\\mu^{-})$ dominated by the $\\rho$ and $\\omega$ resonances: 675 MeV/$c^{2} < m(\\mu^{+}\\mu^{-}) <$ 875 MeV/$c^{2}$. It will be precious in the future, in particular as a normalisation mode in the study of all: $D^{0}\\rightarrow h^{\\...

Charm photoproduction and quantum chromodynamics

International Nuclear Information System (INIS)

Novikov, V.A.; Shifman, M.A.; Vainshtein, A.I.; Zakharov, V.I.

1977-01-01

It is shown that charm photoproduction can be consistently described within asymptotically free field theory. Quantum chromodynamics is used to derive sum rules for the total cross section sigmasub(c)sup(γ) which includes both production of mesons with hidden charm (J/PIS, PIS' and so on) and of charmed particles (pairs DantiD, FantiF and so on). An estimate of sigmasub(c)sup(γ) as a function of energy is given and fast growth is discovered up to energies approximately 1000 GeV. In this energy range sigmasub(c)sup(γ) turns out to be equal to several microbarns. It is argued that measurements of charm photoproduction would give the most direct information on the gluon distribution within a nucleon. All the results are generalized to production of heavier particles containing new quarks. In particular, a simple rescaling law is derived connecting the cross sections for charm and beauty

Ds1*(2860) and Ds3*(2860): candidates for 1D charmed-strange mesons

International Nuclear Information System (INIS)

Song, Qin-Tao; Chen, Dian-Yong; Liu, Xiang; Matsuki, Takayuki

2015-01-01

Newly observed two charmed-strange resonances, D s1 * (2860) and D s3 * (2860), are investigated by calculating their Okubo-Zweig-Iizuka-allowed strong decays, which shows that they are suitable candidates for the 1 3 D 1 and 1 3 D 3 states in the charmed-strange meson family. Our study also predicts other main decay modes of D s1 * (2860) and D s3 * (2860), which can be accessible at the future experiment. In addition, the decay behaviors of the spin partners of D s1 * (2860) and D s3 * (2860), i.e., 1D(2 - ) and 1D'(2 - ), are predicted in this work, which are still missing at present. The experimental search for the missing 1D(2 - ) and 1D'(2 - ) charmed-strange mesons is an intriguing and challenging task for further experiments. (orig.)

Production of excited charmed mesons at LEP

CERN Document Server

Abbaneo, D

2000-01-01

Studies od the production of orbitally excited charmed and charmed strange mesons in e+e- collisions, performed by the LEP collaborations are reviewed. Measurements of the production rates of orbitally excited charmed mesons in semileptonic b decays are presented. Searches for charmed meson radial excitations are also briefly discussed.

Searches for Rare or Forbidden Semileptonic Charm Decays

Energy Technology Data Exchange (ETDEWEB)

Lees, J.P.

2011-08-15

We present searches for rare or forbidden charm decays of the form X{sub c}{sup +} {yields} h{sup {+-}}{ell}{sup {-+}}{ell}{sup ({prime})+}, where X{sub c}{sup +} is a charm hardron (D{sup +}, D{sub s}{sup +}, or {Lambda}{sub c}{sup +}), h{sup {+-}} is a pion, kaon, or proton, and {ell}{sup ({prime}){+-}} is an electron or muon. The analysis is based on 384 fb{sup -1} of e{sup +}e{sup -} annihilation data collected at or close to the {Upsilon}(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signal is observed for any of the 35 decay modes that are investigated. We establish 90% confidence-level upper limits on the branching fractions between 1 x 10{sup -6} and 44 x 10{sup -6} depending on the channel. In most cases, these results represent either the first limits or significant improvements on existing limits for the decay modes studied.

Charm physics 1996 - a retrospective

International Nuclear Information System (INIS)

Golowich, E.

1997-01-01

A pedagogically oriented review is given of progress made over the past year in our understanding of physics related to the charm quark. Included are discussions of the R c deficit, the ψ' anomaly, charm spectroscopy, D nonleptonic decays, searches for flavor-changing neutral currents, new limits on D 0 - anti D 0 mixing and prospects for future experimental studies of the charm sector. (orig.)

Derivation of sum rules for quark and baryon fields. [light-like charges

Energy Technology Data Exchange (ETDEWEB)

Bongardt, K [Karlsruhe Univ. (TH) (Germany, F.R.). Inst. fuer Theoretische Kernphysik

1978-08-21

In an analogous way to the Weinberg sum rules, two spectral-function sum rules for quark and baryon fields are derived by means of the concept of lightlike charges. The baryon sum rules are valid for the case of SU/sub 3/ as well as for SU/sub 4/ and the one-particle approximation yields a linear mass relation. This relation is not in disagreement with the normal linear GMO formula for the baryons. The calculated masses of the first resonance states agree very well with the experimental data.

The Compressed Baryonic Matter experiment at FAIR

Directory of Open Access Journals (Sweden)

Höhne Claudia

2018-01-01

Full Text Available The CBM experiment will investigate highly compressed baryonic matter created in A+A collisions at the new FAIR research center. With a beam energy range up to 11 AGeV for the heaviest nuclei at the SIS 100 accelerator, CBM will investigate the QCD phase diagram in the intermediate range, i.e. at moderate temperatures but high net-baryon densities. This intermediate range of the QCD phase diagram is of particular interest, because a first order phase transition ending in a critical point and possibly new highdensity phases of strongly interacting matter are expected. In this range of the QCD phase diagram only exploratory measurements have been performed so far. CBM, as a next generation, high-luminosity experiment, will substantially improve our knowledge of matter created in this region of the QCD phase diagram and characterize its properties by measuring rare probes such as multi-strange hyperons, dileptons or charm, but also with event-by-event fluctuations of conserved quantities, and collective flow of identified particles. The experimental preparations with special focus on hadronic observables and strangeness is presented in terms of detector development, feasibility studies and fast track reconstruction. Preparations are progressing well such that CBM will be ready with FAIR start. As quite some detectors are ready before, they will be used as upgrades or extensions of already running experiments allowing for a rich physics program prior to FAIR start.

Study of charm production through the decay of B mesons in the BABAR experiment; Etude de la production de charme dans les desintegrations des mesons beaux avec l'experience BABAR

Energy Technology Data Exchange (ETDEWEB)

Couderc, F

2005-04-15

The BABAR experiment, located at SLAC (Stanford, California), has been dedicated, since 1999, to the study of B meson decays produced in electron positron collisions with an energy in the center of mass frame equal to the mass of {epsilon}(4S) resonance. In this experiment, the charged particles identification is provided, in particular by the measurement of the energy loss per length unit in the drift chamber. In order to improve the calibration of this quantity, a selection of electrons/positrons from radiative Bhabha events was performed; with the new sample the charge asymmetry in the charged particles reconstruction was reduced. In B meson decays, the inclusive production of charmed particles (D{sup 0}, D{sup 0}-bar, D{sup {+-}}, D{sub s}{sup {+-}}, {lambda}{sub c}{sup {+-}}) is measured with a new analysis method, made possible by the large statistics accumulated by the BABAR experiment. B and B-bar mesons are produced simultaneously from the {epsilon}(4S) resonance. The events are selected by reconstructing completely one B in a hadronic channel. Charmed particles from the other B are then reconstructed with the remaining tracks. This enables the measurement of the total number of charm produced in B{sup +} and in B{sup 0} decays separating the correlated charm production (quark transitions: b {yields} cX) from the anti-correlated production (quark transitions: b {yields} c-bar X). The results obtained on an integrated luminosity of 210 fb{sup -1} are the following: N{sub c}{sup B{sup +}} = 0.970 {+-} 0.042; N{sub c-}bar{sup B{sup +}} 0.262 {+-} 0.034; N{sub c}{sup B{sup 0}} = 0.950 {+-} 0.057; N{sub c-}bar{sup B{sup 0}} 0.285 {+-} 0.048. This new method also allows the measurement of the momentum of the charmed particles in the B rest frame. Access to the different production mechanisms of these particles is thereby provided. (author)

Compressed baryonic matter experiment at FAIR

Directory of Open Access Journals (Sweden)

Jürgen Eschke

2012-02-01

Full Text Available The Compressed Baryonic Matter (CBM experiment is being planned at the Facility for Antiproton and Ion Research (FAIR, under realization next to the GSI laboratory in Darmstadt, Germany. Its physics programme addresses the QCD phase diagram in the region of highest net baryon densities. Of particular interest are the expected first order phase transition from partonic to hadronic matter, ending in a critical point, and modifcations of hadron properties in the dense medium as a signal of chiral symmetry restoration. Laid out as a fixed-target experiment at the synchrotrons SIS-100/SIS-300, providing magnetic bending power of 100 and 300 T/Fm, the CBM detector will record both proton-nucleus and nucleus-nucleus collisions at beam energies up to 45 AGeV. Hadronic, leptonic and photonic observables will be measured in a large acceptance. The nuclear interaction rates will reach up to 10 MHz to measure extremely rare probes like charm near threshold. This requires the development of novel detector systems, trigger and data acquisition concepts as well as in- novative real-time reconstruction techniques. A key observable of the physics program is a precise measurement of lowmass vector mesons and charmonium in their leptonic decay channel. In CBM, electrons will be identified using a gaseous RICH detector combined with several TRD detectors positioned after a system of silicon tracking stations which are located inside a magnetic dipole field. The concept of the RICH detector, results on R & D as well as feasibility studies and invariant mass distributions of charmonium will be discussed.

Charm Physics at SuperB

International Nuclear Information System (INIS)

Meadows, Brian; Bevan, Adrian

2010-01-01

The study of Charm Decays at SuperB provide unique opportunities to understand the Standard Model and constrain new physics, both at the Y(4S), and at charm threshold. We discuss the physics potential of such measurements from the proposed SuperB experiment with 75 ab -1 of data at the Y(4S) and a subsequent run dedicated to exploiting quantum correlations at the charm threshold. (author)

Baryon-baryon mixing in hypernuclei

International Nuclear Information System (INIS)

Gibson, B.F.

1998-01-01

Implications of few-body hypernuclei for the understanding of the baryon-baryon interaction are examined. Octet-octet coupling effects not present in conventional, non strange nuclei are the focus. The need to identify strangeness -2 hypernuclei to test model predictions is emphasized

Electromagnetic properties of baryons in the constituent quark model

International Nuclear Information System (INIS)

Warns, M.

1992-01-01

The electromagnetic properties of baryons are investigated in the framework of a relativized quark model. The model includes beyond the usual single quark transition ansatz relativistic effects due to the strong interaction and confinement forces between the quarks. Furthermore the center-of-mass motion of the three-quark system is separated off in a Lorentz-invariant way. All relativistic correction terms are obtained by expanding the corresponding relativistic expressions in powers of the quark velocity. In this way recoil effects on the electromagnetic interaction between the photon and the baryon could be explicitly studied. Using the harmonic oscillator wavefunctions with the configuration mixing from the Isgur-Karl model, the form factors of the nucleon and the electromagnetic transition amplitudes both for longitudinally and transversely polarized photons are calculated for the most important baryon resonances. An extension to baryons involving strange quarks is also considered. Comparisons are made with the results of the nonrelativistic quark model and with some other approaches. (orig.)

Probing the interactions of charmed mesons with nuclei in anti p-induced reactions

International Nuclear Information System (INIS)

Golubeva, Ye.S.; Cassing, W.; Kondratyuk, L.A.

2002-01-01

We study the perspectives of resonant and nonresonant charmed-meson production in anti p+A reactions within the Multiple Scattering Monte Carlo (MSMC) approach. We calculate the production of the resonances Ψ(3770), Ψ(4040) and Ψ(4160) on various nuclei, their propagation and decay to D, anti D, D * , anti DD * , D s , anti D s in the medium and vacuum, respectively. The modifications of the open charm vector mesons in the nuclear medium are found to be rather moderate or even small such that dilepton spectroscopy will require an invariant mass resolution of a few MeV. Furthermore, the elastic and inelastic interactions of the open charm mesons in the medium are taken into account, which can be related to (u, d)-, s- or c-quark exchange with nucleons. It is found that by studying the D/ anti D ratio for low momenta in the laboratory (≤2-2.2 GeV/c) as a function of the target mass A stringent constraints on the c-quark exchange cross-section can be obtained. On the other hand, the ratios D - s /D + s as well as D/D - s and D/D + s at low momenta as a function of A will permit to fix independently the strength of the s-quark exchange reaction in D - s N scattering. (orig.)

arXiv Search for baryon-number-violating $\\Xi_b^0$ oscillations

CERN Document Server

Aaij, Roel; LHCb Collaboration; Adinolfi, Marco; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Alfonso Albero, Alejandro; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Andreassi, Guido; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Archilli, Flavio; d'Argent, Philippe; Arnau Romeu, Joan; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Babuschkin, Igor; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baker, Sophie; Balagura, Vladislav; Baldini, Wander; Baranov, Alexander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Baryshnikov, Fedor; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Beiter, Andrew; Bel, Lennaert; Beliy, Nikita; Bellee, Violaine; Belloli, Nicoletta; Belous, Konstantin; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Beranek, Sarah; Berezhnoy, Alexander; Bernet, Roland; Berninghoff, Daniel; Bertholet, Emilie; Bertolin, Alessandro; Betancourt, Christopher; Betti, Federico; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bezshyiko, Iaroslava; Bifani, Simone; Billoir, Pierre; Birnkraut, Alex; Bitadze, Alexander; Bizzeti, Andrea; Bjørn, Mikkel; Blake, Thomas; Blanc, Frederic; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Boettcher, Thomas; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Bordyuzhin, Igor; Borgheresi, Alessio; Borghi, Silvia; Borisyak, Maxim; Borsato, Martino; Bossu, Francesco; Boubdir, Meriem; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Britton, Thomas; Brodzicka, Jolanta; Brundu, Davide; Buchanan, Emma; Burr, Christopher; Bursche, Albert; Buytaert, Jan; Byczynski, Wiktor; Cadeddu, Sandro; Cai, Hao; Calabrese, Roberto; Calladine, Ryan; Calvi, Marta; Calvo Gomez, Miriam; Camboni, Alessandro; Campana, Pierluigi; Campora Perez, Daniel Hugo; 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; Cavallero, Giovanni; Cenci, Riccardo; Chamont, David; Charles, Matthew; Charpentier, Philippe; Chatzikonstantinidis, Georgios; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu Faye; Chitic, Stefan-Gabriel; Chobanova, Veronika; Chrzaszcz, Marcin; Chubykin, Alexsei; Ciambrone, Paolo; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collins, Paula; Colombo, Tommaso; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombs, George; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Costa Sobral, Cayo Mar; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Currie, Robert; D'Ambrosio, Carmelo; Da Cunha Marinho, Franciole; Dall'Occo, Elena; Dalseno, Jeremy; Davis, Adam; De Aguiar Francisco, Oscar; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Serio, Marilisa; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Del Buono, Luigi; Dembinski, Hans Peter; Demmer, Moritz; Dendek, Adam; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Di Nezza, Pasquale; Dijkstra, Hans; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Douglas, Lauren; Dovbnya, Anatoliy; Dreimanis, Karlis; Dufour, Laurent; Dujany, Giulio; Durante, Paolo; Dzhelyadin, Rustem; Dziewiecki, Michal; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Ebert, Marcus; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Farley, Nathanael; Farry, Stephen; Fazzini, Davide; Federici, Luca; Ferguson, Dianne; Fernandez, Gerard; Fernandez Declara, Placido; Fernandez Prieto, Antonio; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fini, Rosa Anna; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fleuret, Frederic; Fohl, Klaus; Fontana, Marianna; Fontanelli, Flavio; Forshaw, Dean Charles; Forty, Roger; Franco Lima, Vinicius; Frank, Markus; Frei, Christoph; Fu, Jinlin; Funk, Wolfgang; Furfaro, Emiliano; Färber, Christian; Gabriel, Emmy; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; Garcia Martin, Luis Miguel; García Pardiñas, Julián; Garra Tico, Jordi; Garrido, Lluis; Garsed, Philip John; Gascon, David; Gaspar, Clara; Gavardi, Laura; Gazzoni, Giulio; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianì, Sebastiana; Gibson, Valerie; Girard, Olivier Göran; Giubega, Lavinia-Helena; Gizdov, Konstantin; Gligorov, Vladimir; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gorelov, Igor Vladimirovich; Gotti, Claudio; Govorkova, Ekaterina; Grabowski, Jascha Peter; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greim, Roman; Griffith, Peter; Grillo, Lucia; Gruber, Lukas; Gruberg Cazon, Barak Raimond; Grünberg, Oliver; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Göbel, Carla; Hadavizadeh, Thomas; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hamilton, Brian; Han, Xiaoxue; Hancock, Thomas Henry; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; Hasse, Christoph; Hatch, Mark; He, Jibo; Hecker, Malte; Heinicke, Kevin; Heister, Arno; Hennessy, Karol; Henrard, Pierre; Henry, Louis; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hombach, Christoph; Hopchev, Plamen Hristov; Huard, Zachary; Hulsbergen, Wouter; Humair, Thibaud; Hushchyn, Mikhail; Hutchcroft, David; Ibis, Philipp; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; Jiang, Feng; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Karacson, Matthias; Kariuki, James Mwangi; Karodia, Sarah; Kazeev, Nikita; Kecke, Matthieu; Kelsey, Matthew; Kenzie, Matthew; Ketel, Tjeerd; Khairullin, Egor; Khanji, Basem; Khurewathanakul, Chitsanu; Kirn, Thomas; Klaver, Suzanne; Klimaszewski, Konrad; Klimkovich, Tatsiana; Koliiev, Serhii; Kolpin, Michael; Komarov, Ilya; Kopecna, Renata; Koppenburg, Patrick; Kosmyntseva, Alena; Kotriakhova, Sofia; Kozeiha, Mohamad; Kravchuk, Leonid; Kreps, Michal; 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; Lanfranchi, Gaia; Langenbruch, Christoph; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; Leflat, Alexander; Lefrançois, Jacques; Lefèvre, Regis; Lemaitre, Florian; Lemos Cid, Edgar; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Pei-Rong; Li, Tenglin; Li, Yiming; Li, Zhuoming; Likhomanenko, Tatiana; Lindner, Rolf; Lionetto, Federica; Lisovskyi, Vitalii; Liu, Xuesong; Loh, David; Loi, Angelo; Longstaff, Iain; Lopes, Jose; Lucchesi, Donatella; Lucio Martinez, Miriam; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Lusiani, Alberto; Lyu, Xiao-Rui; Machefert, Frederic; Maciuc, Florin; Macko, Vladimir; Mackowiak, Patrick; Maddrell-Mander, Samuel; Maev, Oleg; Maguire, Kevin; Maisuzenko, Dmitrii; Majewski, Maciej Witold; Malde, Sneha; Malinin, Alexander; Maltsev, Timofei; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Marangotto, Daniele; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marinangeli, Matthieu; Marino, Pietro; Marks, Jörg; Martellotti, Giuseppe; Martin, Morgan; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massacrier, Laure Marie; Massafferri, André; Matev, Rosen; Mathad, Abhijit; Mathe, Zoltan; Matteuzzi, Clara; Mauri, Andrea; Maurice, Emilie; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McNab, Andrew; McNulty, Ronan; Mead, James Vincent; Meadows, Brian; Meaux, Cedric; Meier, Frank; Meinert, Nis; Melnychuk, Dmytro; Merk, Marcel; Merli, Andrea; Michielin, Emanuele; Milanes, Diego Alejandro; Millard, Edward James; Minard, Marie-Noelle; Minzoni, Luca; Mitzel, Dominik Stefan; Mogini, Andrea; Molina Rodriguez, Josue; Mombacher, Titus; Monroy, Igancio Alberto; Monteil, Stephane; Morandin, Mauro; Morello, Michael Joseph; Morgunova, Olga; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Mulder, Mick; Müller, Dominik; Müller, Janine; Müller, Katharina; Müller, Vanessa; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nandi, Anita; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Thi Dung; Nguyen-Mau, Chung; Nieswand, Simon; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Nogay, Alla; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Oldeman, Rudolf; Onderwater, Gerco; Ossowska, Anna; Otalora Goicochea, Juan Martin; Owen, Patrick; Oyanguren, Maria Aranzazu; Pais, Preema Rennee; Palano, Antimo; Palutan, Matteo; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Parker, William; Parkes, Christopher; Passaleva, Giovanni; Pastore, Alessandra; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Petridis, Konstantinos; Petrolini, Alessandro; Petrov, Aleksandr; Petruzzo, Marco; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pikies, Malgorzata; Pinci, Davide; Pistone, Alessandro; Piucci, Alessio; Placinta, Vlad-Mihai; Playfer, Stephen; Plo Casasus, Maximo; Polci, Francesco; Poli Lener, Marco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Pomery, Gabriela Johanna; Ponce, Sebastien; Popov, Alexander; Popov, Dmitry; Poslavskii, Stanislav; Potterat, Cédric; Price, Eugenia; Prisciandaro, Jessica; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Pullen, Hannah Louise; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Quintana, Boris; Rachwal, Bartlomiej; Rademacker, Jonas; Rama, Matteo; Ramos Pernas, Miguel; Rangel, Murilo; Raniuk, Iurii; Ratnikov, Fedor; Raven, Gerhard; Ravonel Salzgeber, Melody; Reboud, Meril; Redi, Federico; Reichert, Stefanie; dos Reis, Alberto; Remon Alepuz, Clara; Renaudin, Victor; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vicente; Robbe, Patrick; Robert, Arnaud; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Rodriguez Perez, Pablo; Rogozhnikov, Alexey; Roiser, Stefan; Rollings, Alexandra Paige; Romanovskiy, Vladimir; Romero Vidal, Antonio; Ronayne, John William; Rotondo, Marcello; Rudolph, Matthew Scott; Ruf, Thomas; Ruiz Valls, Pablo; Ruiz Vidal, Joan; Saborido Silva, Juan Jose; Sadykhov, Elnur; Sagidova, Naylya; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santimaria, Marco; Santovetti, Emanuele; Sarpis, Gediminas; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schael, Stefan; Schellenberg, Margarete; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmelzer, Timon; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schreiner, HF; Schubert, Konstantin; Schubiger, Maxime; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Sepulveda, Eduardo Enrique; Sergi, Antonino; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Siddi, Benedetto Gianluca; Silva Coutinho, Rafael; Silva de Oliveira, Luiz Gustavo; Simi, Gabriele; Simone, Saverio; Sirendi, Marek; Skidmore, Nicola; Skwarnicki, Tomasz; Smith, Eluned; Smith, Iwan Thomas; Smith, Jackson; Smith, Mark; Soares Lavra, Lais; Sokoloff, Michael; Soler, Paul; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Stefko, Pavol; Stefkova, Slavomira; Steinkamp, Olaf; Stemmle, Simon; Stenyakin, Oleg; Stepanova, Margarita; Stevens, Holger; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Stramaglia, Maria Elena; Straticiuc, Mihai; Straumann, Ulrich; Sun, Jiayin; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Syropoulos, Vasileios; Szczekowski, Marek; Szumlak, Tomasz; Szymanski, Maciej Pawel; T'Jampens, Stephane; Tayduganov, Andrey; Tekampe, Tobias; Tellarini, Giulia; Teubert, Frederic; Thomas, Eric; van Tilburg, Jeroen; Tilley, Matthew James; Tisserand, Vincent; Tobin, Mark; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Toriello, Francis; Tourinho Jadallah Aoude, Rafael; Tournefier, Edwige; Traill, Murdo; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tully, Alison; Tuning, Niels; Ukleja, Artur; Usachov, Andrii; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagner, Alexander; Vagnoni, Vincenzo; Valassi, Andrea; Valat, Sebastien; Valenti, Giovanni; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vecchi, Stefania; van Veghel, Maarten; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Venkateswaran, Aravindhan; Verlage, Tobias Anton; Vernet, Maxime; Vesterinen, Mika; Viana Barbosa, Joao Vitor; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Viemann, Harald; Vilasis-Cardona, Xavier; Vitti, Marcela; Volkov, Vladimir; Vollhardt, Achim; Voneki, Balazs; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Vázquez Sierra, Carlos; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wang, Jianchun; Ward, David; Wark, Heather Mckenzie; Watson, Nigel; Websdale, David; Weiden, Andreas; Whitehead, Mark; Wicht, Jean; Wilkinson, Guy; Wilkinson, Michael; Williams, Mark Richard James; Williams, Matthew; Williams, Mike; Williams, Timothy; Wilson, Fergus; Wimberley, Jack; Winn, Michael Andreas; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wraight, Kenneth; Wyllie, Kenneth; Xie, Yuehong; Xu, Zhirui; Yang, Zhenwei; Yang, Zishuo; Yao, Yuezhe; Yin, Hang; Yu, Jiesheng; Yuan, Xuhao; Yushchenko, Oleg; Zarebski, Kristian Alexander; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Yanxi; Zhelezov, Alexey; Zheng, Yangheng; Zhu, Xianglei; Zhukov, Valery; Zonneveld, Jennifer Brigitta; Zucchelli, Stefano

2017-11-03

A search for baryon-number-violating $\\Xi_b^0$ oscillations is performed with a sample of $pp$ collision data recorded by the LHCb experiment, corresponding to an integrated luminosity of 3 fb$^{-1}$. The baryon number at the moment of production is identified by requiring that the $\\Xi_b^0$ come from the decay of a resonance $\\Xi_b^{*-} \\to \\Xi_b^0 \\pi^-$ or $\\Xi_b^{\\prime-} \\to \\Xi_b^0 \\pi^-$, and the baryon number at the moment of decay is identified from the final state using the decays $\\Xi_b^0 \\to \\Xi_c^+ \\pi^-, ~ \\Xi_c^+ \\to p K^- \\pi^+$. No evidence of baryon number violation is found, and an upper limit is set on the oscillation rate of $\\omega < 0.08$ ps$^{-1}$, where $\\omega$ is the associated angular frequency.

Search for narrow baryon resonances (of masses through 3.4 and 5 GeV) through a π-p large angle elastic scattering formation experiment

International Nuclear Information System (INIS)

Chauveau, J.

1981-01-01

This work describes a search for narrow baryon resonances (of masses between 3.4 and 5 GeV) through a π - p large angle elastic scattering formation experiment. An optimization of the sensitivity of the experiment to detect resonances is obtained by the measurement of the central part of the angular distribution (/cos theta*/ -4 . The apparatus and data analysis are described in details. No narrow resonance has been found, the sensitivity of the experiment being characterized by a width GAMMA approximately equal to 1 MeV and an elasticity x approximately equal to 0.01. Finally, the differential cross section measurement is compared to some parton models [fr

Charming surprise

CERN Multimedia

Antonella Del Rosso

2011-01-01

The CP violation in charm quarks has always been thought to be extremely small. So, looking at particle decays involving matter and antimatter, the LHCb experiment has recently been surprised to observe that things might be different. Theorists are on the case. The study of the physics of the charm quark was not in the initial plans of the LHCb experiment, whose letter “b” stands for “beauty quark”. However, already one year ago, the Collaboration decided to look into a wider spectrum of processes that involve charm quarks among other things. The LHCb trigger allows a lot of these processes to be selected, and, among them, one has recently shown interesting features. Other experiments at b-factories have already performed the same measurement but this is the first time that it has been possible to achieve such high precision, thanks to the huge amount of data provided by the very high luminosity of the LHC. “We have observed the decay modes of the D0, a pa...

Possibility of Pc (4380) and Pc (4450) penta-quark states as candidates for charmed meson-baryon molecular states

International Nuclear Information System (INIS)

Vinodkumar, P.C.; Patel, Smruti

2015-01-01

The recent discovery of two hidden-charm resonances by the LHCb Collaboration in the J/ψp invariant mass distribution denoted as P c , with masses (widths) (4380 ± 8 ± 29) MeV ((205±18±86) MeV) and (4449.8±1.7±2.5) MeV ((39±5±19) MeV), respectively has immediately attracted a lot of attention from the whole community since they could be the long-searching-for pentaquark states in the heavy flavor sector. The high mass and the decay channel J/ψp suggest that these two states must have minimal quark content of cc¯uud, which can be called pentaquark-charmonium states. Soon after the experimental results released, much theoretical effort was paid into this field and many ideas were inspired.There have been several attempted assignments, such as the molecule-like pentaquark states, the diquark-diquark-antiquark type pentaquark states the diquark-triquark type pentaquark states, re-scattering effects, etc. Search for pentaquarks is one of the most challenging theoretical and experimental problems in the physics of strong interaction and quantum chromodynamics (QCD). The last rise and down of the pentaquark study happened at ten years ago due to claim of finding of the strange pentaquark Θ by the LEPS collaboration. But now this topic received serious attention since discovery of P c has rekindled the hope for long searched mysterious pentaquark states

Study of flavor-tagged baryon production in B decay

Energy Technology Data Exchange (ETDEWEB)

Ammar, R.; Baringer, P.; Bean, A.; Besson, D.; Coppage, D.; Copty, N.; Davis, R.; Hancock, N.; Kotov, S.; Kravchenko, I.; Kwak, N. [University of Kansas, Lawrence, Kansas 66045 (United States); Kubota, Y.; Lattery, M.; Nelson, J.K.; Patton, S.; Poling, R.; Riehle, T.; Savinov, V.; Wang, R. [University of Minnesota, Minneapolis, Minnesota 55455 (United States); Alam, M.S.; Kim, I.J.; Ling, Z.; Mahmood, A.H.; ONeill, J.J.; Severini, H.; Sun, C.R.; Timm, S.; Wappler, F. [State University of New York at Albany, Albany, New York 12222 (United States); Crawford, G.; Duboscq, J.E.; Fulton, R.; Fujino, D.; Gan, K.K.; Honscheid, K.; Kagan, H.; Kass, R.; Lee, J.; Sung, M.; White, C.; Wanke, R.; Wolf, A.; Zoeller, M.M. [Ohio State University, Columbus, Ohio, 43210 (United States); Fu, X.; Nemati, B.; Ross, W.R.; Skubic, P.; Wood, M. [University of Oklahoma, Norman, Oklahoma 73019 (United States); Bishai, M.; Fast, J.; Gerndt, E.; Hinson, J.W.; Miao, T.; Miller, D.H.; Modesitt, M.; Shibata, E.I.; Shipsey, I.P.; Wang, P.N. [Purdue University, West Lafayette, Indiana 47907 (United States); Gibbons, L.; Johnson, S.D.; Kwon, Y.; Roberts, S.; Thorndike, E.H. [University of Rochester, Rochester, New York 14627 (United States); Coan, T.E.; Dominick, J.; Fadeyev, V.; Korolkov, I.; Lambrecht, M.; Sanghera, S.; Shelkov, V.; Stroynowski, R.; Volobouev, I.; Wei, G. [Southern Methodist University, Dallas, Texas 75275 (United States); Artuso, M.; Gao, M.; Goldberg, M.; He, D.; Horwitz, N.; Kopp, S.; Moneti, G.C.; Mountain, R.; Muheim, F.; Mukhin, Y.; Playfer, S.; Skwarnicki, T.; Stone, S.; Xing, X. [Syracuse University, Syracuse, New York 13244 (United States); Bartelt, J.; Csorna, S.E.; Jain, V.; Marka, S. [Vanderbilt University, Nashville, Tennessee 37235 (United States); Gibaut, D.; Kinoshita, K.; Pomianowski, P.; Schrenk, S. [Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 (United States); Barish, B.; Chadha, M.; Chan, S.; Cowen, D.

1997-01-01

Using data collected on the {Upsilon}(4S) resonance and the nearby continuum by the CLEO-II detector, we have studied combinations of baryons with leptons produced in the process {Upsilon}(4S){r_arrow}B{bar B}, B{r_arrow}lepton+X, {bar B}{r_arrow}baryon+X. Our results do not support models which Attribute the bulk of {Lambda}{sub c} production in {bar B} decay to the process b{r_arrow}cW{sup {minus}},W{sup {minus}}{r_arrow}{bar c}s. {copyright} {ital 1997} {ital The American Physical Society}

Charmed hadron production by neutrinos

Energy Technology Data Exchange (ETDEWEB)

Ushida, N [Aichi Univ. of Education, Kariya (Japan). Dept. of Physics; Kondo, T [Fermi National Accelerator Lab., Batavia, IL (USA); Fujioka, G; Fukushima, J; Takahashi, Y; Tatsumi, S; Yokoyama, C [Kobe Univ. (Japan). Dept. of Physics; Homma, Y; Tsuzuki, Y [Kobe Univ. (Japan). Coll. of Liberal Arts; Bahk, S

1983-02-03

Charmed hadron production has been studied using a hybrid emulsion spectrometer in the Fermilab wide-band neutrino beam. The relative rates of D/sup 0/, D/sup +/, F/sup +/, and ..lambda..sub(c)/sup +/ production have been measured - the fraction of D mesons is 69 +- 8/10%. Momentum, transverse momentum, Feynman X, and fragmentation (Z) distributions are presented. The mean Z for charmed hadrons is 0.59 +- 0.03 (+- 0.03). Charmed target fragments have been observed.

Heavy quark symmetry and weak decays of the b-baryons in pentaquarks with a c anti c component

Energy Technology Data Exchange (ETDEWEB)

Ali, Ahmed [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Ahmed, Ishtiaq; Rehman, Abdur [Quaid-i-Azam Univ., Islamabad (Pakistan). National Centre for Physics; Aslam, M. Jamil [Quaid-i-Azam Univ., Islamabad (Pakistan). Physics Dept.

2016-06-15

The discovery of the baryonic states P{sup +}{sub c}(4380) and P{sup +}{sub c}(4450) by the LHCb collaboration in the process pp→b anti b→Λ{sup 0}{sub b}X, followed by the decay Λ{sup 0}{sub b}→J/ψpK{sup -} has evoked a lot of theoretical interest. These states have the minimal quark content c anti cuud, as suggested by their discovery mode J/ψ p, and the preferred J{sup P} assignments are (5)/(2){sup +} for the P{sup +}{sub c}(4450) and (3)/(2){sup -} for the P{sup +}{sub c}(4380). In the compact pentaquark hypothesis, in which they are interpreted as hidden charm diquark-diquark-antiquark baryons, the assigned spin and angular momentum quantum numbers are P{sup +}{sub c}(4380)={ anti c[cu]_s_=_1[ud]_s_=_1; L_P=0, J"P=(3)/(2)"-} and P{sup +}{sub c}(4450)={ anti c[cu]_s_=_1[ud]_s_=_0; L_P=1, J"P=(5)/(2)"+}. The subscripts denote the spin of the diquarks and L{sub P}=0,1 are the orbital angular momentum quantum numbers of the pentaquarks. We point out that heavy quark limit, the spin of the light diquark in heavy baryons becomes a good quantum number, which has consequences for the decay Λ{sup 0}{sub b}→J/ψpK{sup -}. With the quantum numbers assigned above for the two pentaquarks, this would allow only the higher mass pentaquark state P{sup +}{sub c}(4450) having [ud]{sub s=0} to be produced in Λ{sup 0}{sub b} decays, whereas the lower mass state P{sup +}{sub c}(4380) having [ud]{sub s=1} is disfavored, requiring a different interpretation. Pentaquark spectrum is rich enough to accommodate a J{sup P}=(3)/(2){sup -} state, which has the correct light diquark spin { anti c[cu]_s_=_1[ud]_s_=_0; L_P=0, J"P=(3)/(2)"-} to be produced in Λ{sup 0}{sub b} decays. Assuming that the mass difference between the charmed pentaquarks which differ in the orbital angular momentum L by one unit is similar to the corresponding mass difference in the charmed baryons, m[Λ{sup +}{sub c}(2625); J{sup P}=(3)/(2){sup -}]-m[Λ{sup +}{sub c}(2286); J{sup P}=(1)/(2){sup +}]�

A Tau-Charm Factory at CEBAF

Energy Technology Data Exchange (ETDEWEB)

Seth, K.K. [Northwestern Univ., Evanston, IL (United States)

1994-04-01

It is proposed that a Tau Charm Factory represents a natural extension of CEBAF into higher energy domains. The exciting nature of the physics of charm quarks and tau leptons is briefly reviewed and it is suggested that the concept of a linac-ring collider as a Tau Charm Factory at CEBAF should be seriously studied.

Lecture III. Production of charm

International Nuclear Information System (INIS)

Anon.

1978-01-01

The production of charmed particles is discussed using simple arguments to understand the production cross sections in various situations in a survey of masses, names, decay modes, and production mechanisms. Thus an estimation can be made of the best place to find charmed particles and the places where it is more difficult to find them. Discussed are e + e - annihilation, peripheral production in hadron collisions, inclusive production in hadron collisions, production in (ν, anti ν)N reactions, and photoproduction of charm. 12 references

Cheias de Charme (Full of Charm The working class in cyberculture paradise

Directory of Open Access Journals (Sweden)

Gisela Grangeiro da Silva Castro

2012-12-01

Full Text Available Given the leadership of Rede Globo in the Brazilian media scene, this paper aims to analyze marketing strategies present in the telenovela Cheias de Charme (Full of Charm in order to elicit interaction with internet social networks. The telenovela takes part in the social pedagogy, especially aimed at the audience stratum for whom television is the main source of daily leisure. Cheias de Charme focuses on class C portraying domestic workers as main characters. In today’s complex communication ecosystem, we highlight the growing access of lower income classes to digital media and the relevance of the Brazilians in digital social networks. By examining this example of transmedia storytelling we discuss today’s striking HYBRIDIZATION between communication, consumption and entertainment.

Search for a narrow baryonic resonance decaying to Ks0p or Ks0p¯ in deep inelastic scattering at HERA

Science.gov (United States)

H1 Collaboration; Aktas, A.; Andreev, V.; Anthonis, T.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Babaev, A.; Backovic, S.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Baumgartner, S.; Becker, J.; Beckingham, M.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, N.; Bizot, J. C.; Boenig, M.-O.; Boudry, V.; Bracinik, J.; Brandt, G.; Brisson, V.; Bruncko, D.; Büsser, F. W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A. J.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Contreras, J. G.; Coughlan, J. A.; Cox, B. E.; Cozzika, G.; Cvach, J.; Dainton, J. B.; Dau, W. D.; Daum, K.; de Boer, Y.; Delcourt, B.; Del Degan, M.; de Roeck, A.; de Wolf, E. A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eliseev, A.; Elsen, E.; Essenov, S.; Falkewicz, A.; Faulkner, P. J. W.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Finke, L.; Fleischer, M.; Flucke, G.; Fomenko, A.; Franke, G.; Frisson, T.; Gabathuler, E.; Garutti, E.; Gayler, J.; Gerlich, C.; Ghazaryan, S.; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Grab, C.; Greenshaw, T.; Gregori, M.; Grell, B. R.; Grindhammer, G.; Gwilliam, C.; Haidt, D.; Hajduk, L.; Hansson, M.; Heinzelmann, G.; Henderson, R. C. W.; Henschel, H.; Herrera, G.; Hildebrandt, M.; Hiller, K. H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Hreus, T.; Hussain, S.; Ibbotson, M.; Ismail, M.; Jacquet, M.; Janauschek, L.; Janssen, X.; Jemanov, V.; Jönsson, L.; Johnson, D. P.; Jung, A. W.; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I. R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knies, G.; Knutsson, A.; Korbel, V.; Kostka, P.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Krüger, K.; Landon, M. P. J.; Lange, W.; Laštovička-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Lobodzinska, E.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.-I.; Lueders, H.; Lüke, D.; Lux, T.; Lytkin, L.; Makankine, A.; Malden, N.; Malinovski, E.; Mangano, S.; Marage, P.; Marshall, R.; Marti, L.; Martisikova, M.; Martyn, H.-U.; Maxfield, S. J.; Mehta, A.; Meier, K.; Meyer, A. B.; Meyer, H.; Meyer, J.; Michels, V.; Mikocki, S.; Milcewicz-Mika, I.; Milstead, D.; Mladenov, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J. V.; Mozer, M. U.; Müller, K.; Murín, P.; Nankov, K.; Naroska, B.; Naumann, Th.; Newman, P. R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J. E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Papadopoulou, T.; Pascaud, C.; Patel, G. D.; Peng, H.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Pitzl, D.; Plačakytė, R.; Portheault, B.; Povh, B.; Prideaux, P.; Rahmat, A. J.; Raicevic, N.; Reimer, P.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D. P. C.; Sauvan, E.; Schätzel, S.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schöning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shaw-West, R. N.; Sheviakov, I.; Shtarkov, L. N.; Sloan, T.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, A.; Steder, M.; Stella, B.; Stiewe, J.; Stoilov, A.; Straumann, U.; Sunar, D.; Tchoulakov, V.; Thompson, G.; Thompson, P. D.; Toll, T.; Tomasz, F.; Traynor, D.; Truöl, P.; Tsakov, I.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, K.; Urban, M.; Usik, A.; Utkin, D.; Valkárová, A.; Vallée, C.; van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Veelken, C.; Vinokurova, S.; Volchinski, V.; Wacker, K.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Wessels, M.; Wessling, B.; Wissing, Ch.; Wolf, R.; Wünsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Žáček, J.; Zálešák, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zhu, Y. C.; Zimmermann, J.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.

2006-08-01

A search for a narrow baryonic resonance decaying to Ks0p or Ks0p¯ is carried out in deep inelastic ep scattering with the H1 detector at HERA. Such a resonance could be a strange pentaquark Θ, evidence for which has been reported by several experiments. The Ks0p and Ks0p¯ invariant mass distributions presented here do not show any significant peak in the mass range from threshold up to 1.7 GeV. Mass dependent upper limits on σ(ep→eΘX)×BR(Θ→Kp) are obtained at the 95% confidence level.

Charmed particle lifetimes

International Nuclear Information System (INIS)

Rosner, J.L.

1979-01-01

Conventional estimates are reviewed for charmed particle lifetimes. Free-quark models give values of (a few) x 10 -13 sec to (a few) x 10 -12 sec. The shorter of these values also follows from an extrapolation based on D → Ke/sup nu/. Possible differences among the lifetimes and production rates of D 0 , D + , F + , C 0 + , the heavy lepton tau, and the fifth quark b are discussed. Extreme values of mixing angles in a six-quark model could extend charmed particle lifetimes by a factor of at most three from the above estimates, while shorter lifetimes than those predicted could occur for some species like D 0 or F + if their nonleptonic decays were enhanced. The predictions are discussed in the light of some current experimental results, and it is estimated that sigma(pp → charm) approx. = 10 μb at 400 GeV/c. 95 references

Rotational-vibrational coupling in the BPS Skyrme model of baryons

Energy Technology Data Exchange (ETDEWEB)

Adam, C.; Naya, C.; Sanchez-Guillen, J. [Departamento de Física de Partículas, Universidad de Santiago de Compostela and Instituto Galego de Física de Altas Enerxias (IGFAE), E-15782 Santiago de Compostela (Spain); Wereszczynski, A. [Institute of Physics, Jagiellonian University, Reymonta 4, Kraków (Poland)

2013-11-04

We calculate the rotational-vibrational spectrum in the BPS Skyrme model for the hedgehog skyrmion with baryon number one. The resulting excitation energies for the nucleon and delta Roper resonances are slightly above their experimental values. Together with the fact that in the standard Skyrme model these excitation energies are significantly lower than the experimental ones, this provides strong evidence for the conjecture that the inclusion of the BPS Skyrme model is required for a successful quantitative description of physical properties of baryons and nuclei.

Beth-Uhlenbeck approach for repulsive interactions between baryons in a hadron gas

Science.gov (United States)

Vovchenko, Volodymyr; Motornenko, Anton; Gorenstein, Mark I.; Stoecker, Horst

2018-03-01

The quantum mechanical Beth-Uhlenbeck (BU) approach for repulsive hard-core interactions between baryons is applied to the thermodynamics of a hadron gas. The second virial coefficient a2—the "excluded volume" parameter—calculated within the BU approach is found to be temperature dependent, and it differs dramatically from the classical excluded volume (EV) model result. At temperatures T =100 -200 MeV, the widely used classical EV model underestimates the EV parameter for nucleons at a given value of the nucleon hard-core radius by large factors of 3-4. Previous studies, which employed the hard-core radii of hadrons as an input into the classical EV model, have to be re-evaluated using the appropriately rescaled EV parameters. The BU approach is used to model the repulsive baryonic interactions in the hadron resonance gas (HRG) model. Lattice data for the second- and fourth-order net baryon susceptibilities are described fairly well when the temperature dependent BU baryonic excluded volume parameter corresponds to nucleon hard-core radii of rc=0.25 -0.3 fm. Role of the attractive baryonic interactions is also considered. It is argued that HRG model with a constant baryon-baryon EV parameter vN N≃1 fm3 provides a simple yet efficient description of baryon-baryon interaction in the crossover temperature region.

Lattice calculation of nonleptonic charm decays

International Nuclear Information System (INIS)

Simone, J.N.

1991-11-01

The decays of charmed mesons into two body nonleptonic final states are investigated. Weak interaction amplitudes of interest in these decays are extracted from lattice four-point correlation functions using a effective weak Hamiltonian including effects to order G f in the weak interactions yet containing effects to all orders in the strong interactions. The lattice calculation allows a quantitative examination of non-spectator processes in charm decays helping to elucidate the role of effects such as color coherence, final state interactions and the importance of the so called weak annihilation process. For D → Kπ, we find that the non-spectator weak annihilation diagram is not small, and we interpret this as evidence for large final state interactions. Moreover, there is indications of a resonance in the isospin 1/2 channel to which the weak annihilation process contributes exclusively. Findings from the lattice calculation are compared to results from the continuum vacuum saturation approximation and amplitudes are examined within the framework of the 1/N expansion. Factorization and the vacuum saturation approximation are tested for lattice amplitudes by comparing amplitudes extracted from lattice four-point functions with the same amplitude extracted from products of two-point and three-point lattice correlation functions arising out of factorization and vacuum saturation

A New Method for Obtaining the Baryons Mass under the Killingbeck Plus Isotonic Oscillator Potentials

Directory of Open Access Journals (Sweden)

Nasrin Salehi

2016-01-01

Full Text Available The spectrum of ground state and excited baryons (N, Δ, Λ, Σ, Ξ, and Ω particles has been investigated by using nonrelativistic quantum mechanics under the Killingbeck plus isotonic oscillator potentials. Using the Jacobi coordinates, anzast method, and generalized Gürsey Radicati (GR mass formula the three-body-wave equation is solved to calculate the different states of the considered baryons. A comparison between our calculations and the available experimental data shows that the position of the Roper resonances of the nucleon, the ground states, and the excited multiplets up to three GeV are in general well reproduced. Also one can conclude that the interaction between the quark constituents of baryon resonances could be described adequately by using the combination of Killingbeck and isotonic oscillator potentials form.

The Compressed Baryonic Matter Experiment at FAIR

Directory of Open Access Journals (Sweden)

Heuser J.M.

2011-04-01

Full Text Available The Compressed Baryonic Matter (CBM experiment is being planned at the international research centre FAIR, under realization next to the GSI laboratory in Darmstadt, Germany. Its physics programme addresses the QCD phase diagram in the region of highest net baryon densities. Of particular interest are the expected first order phase transition from partonic to hadronic matter, ending in a critical point, and modifications of hadron properties in the dense medium as a signal of chiral symmetry restoration. Laid out as a fixed-target experiment at the synchrotrons SIS-100/SIS-300, providing magnetic bending power of 100 and 300 T/m, the CBM detector will record both proton-nucleus and nucleus-nucleus collisions at beam energies up to 45A GeV. Hadronic, leptonic and photonic observables have to be measured with large acceptance. The nuclear interaction rates will reach up to 10 MHz to measure extremely rare probes like charm near threshold. Two versions of the experiment are being studied, optimized for either electron-hadron or muon identification, combined with silicon detector based charged-particle tracking and micro-vertex detection. The research programme will start at SIS-100 with ion beams between 2 and 11A GeV, and protons up to energies of 29 GeV using the HADES detector and an initial configuration of the CBM experiment. The CBM physics requires the development of novel detector systems, trigger and data acquisition concepts as well as innovative real-time reconstruction techniques. Progress with feasibility studies of the experiment and the development of its detector systems are discussed.

Is a charmed axial-vector meson already found

International Nuclear Information System (INIS)

Matsuda, S.

1976-12-01

A calculation is presented of the production rate via e + e - annihilation for a charmed p-wave meson of Jsup(P) = 1 + , based on a non-relativistic quark model of charmed hadrons. The results strongly suggest that the charmed axial-vector meson should be found copiously in association with a ground-state charmed meson. (author)

Strange b baryon production and lifetime in Z decays

CERN Document Server

Buskulic, Damir; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Nief, J Y; Odier, P; Pietrzyk, B; Casado, M P; Chmeissani, M; Crespo, J M; Delfino, M C; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Garrido, L; Juste, A; Martínez, M; Orteu, S; Padilla, C; Park, I C; Pascual, A; Perlas, J A; Riu, I; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Alemany, R; Bazarko, A O; Bonvicini, G; Cattaneo, M; Comas, P; Coyle, P; Drevermann, H; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Lutters, G; Martin, E B; Mato, P; Minten, Adolf G; Miquel, R; Mir, L M; Moneta, L; Oest, T; Pacheco, A; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schmitt, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wagner, A; Ajaltouni, Ziad J; Barrès, A; Boyer, C; Falvard, A; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rosnet, P; Rossignol, J M; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Kyriakis, A; Markou, C; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Rougé, A; Rumpf, M; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Casper, David William; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Dorris, S J; Halley, A W; Knowles, I G; Lynch, J G; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Teixeira-Dias, P; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Geweniger, C; Graefe, G; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Schmidt, M; Sommer, J; Stenzel, H; Tittel, K; Werner, S; Wunsch, M; Abbaneo, D; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Moutoussi, A; Nash, J; Sedgbeer, J K; Stacey, A M; Williams, M D; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Williams, M I; Galla, A; Giehl, I; Greene, A M; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Bencheikh, A M; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Diaconu, C A; Etienne, F; Konstantinidis, N P; Payre, P; Rousseau, D; Talby, M; Sadouki, A; Thulasidas, M; Trabelsi, K; Aleppo, M; Ragusa, F; Abt, I; Assmann, R W; Bauer, C; Blum, Walter; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Jakobs, K; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Choi, Y; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Höcker, A; Jacholkowska, A; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Nikolic, I A; Park, H J; Schune, M H; Simion, S; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Rizzo, G; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Vannini, C; Verdini, P G; Walsh, J; Blair, G A; Bryant, L M; Cerutti, F; Chambers, J T; Gao, Y; Green, M G; Medcalf, T; Perrodo, P; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Maley, P; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Marx, B; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Boswell, R; Brew, C A J; Cartwright, S L; Combley, F; Köksal, A; Lehto, M H; Newton, W M; Reeve, J; Thompson, L F; Böhrer, A; Brandt, S; Büscher, V; Cowan, G D; Grupen, Claus; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Musolino, G; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Greening, T C; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Walsh, A M; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

1996-01-01

In a data sample of approximately four million hadronic Z decays recorded with the ALEPH detector from 1990 to 1995, a search for the strange b baryon Xi_b is performed with a study of Xi-lepton correlations. Forty-four events with same sign Xi- l- combinations are found whereas 8.4 are expected based on on the rate of opposite sign Xi- l+ combinations. This significant excess is interpreted as evidence for Xi_b semileptonic decays. The measured product branching ratio is: Br( b -> Xi_b) Br( Xi_b -> Xc X l- nu) Br( Xc -> Xi- X') = (5.4 +/- 1.1(stat) +/- 0.8(syst) ) 10**-4 per lepton species, averaged over electrons and muons, with Xc a charmed baryo\\ n. The Xi_b lifetime is measured to be : tau = 1.35 (+0.37 -0.28 (stat)) (+0.15 -0.17 (syst)) ps.

From meson-baryon scattering to meson photoproduction

Energy Technology Data Exchange (ETDEWEB)

Mai, Maxim

2013-09-01

In the present work we investigate the properties of the lowest baryon resonances. The starting point of our analyses is the low-energy effective theory of quantum chromodynamics, called chiral perturbation theory. As such it describes the long-range observables in terms of the low-energy effects, while the high-energy effects are subsumed in the so-called low-energy constants. In the region of the aforesaid lowest baryon resonances any strict perturbative expansion fails and some resummation scheme is required. For this we employ the Bethe-Salpeter equation (BSE) which guarantees the exact unitarity of the S-matrix and allows to generate resonances dynamically, however, abandoning some other basic principles of quantum field theory as described in chapter 2. Restricting the driving term of this equation to local terms of the second chiral order, we derive an exact solution of the BSE for meson-baryon scattering in chapter 2. Without putting the interaction kernel on shell we preserve the exact correspondence of this solution to an infinite chain of Feynman diagrams. In chapter 4 we apply this ansatz for antikaon-nucleon scattering, trying to get a new insight into the nature of the subthreshold resonance, i.e. {Lambda}(1405). The properties of this resonance have been debated for decades and in recent years it has again attracted a lot of attention by theoreticians since this resonance can be dynamically generated from the so-called chiral unitary approaches. Moreover, the recent measurement of the energy shift and width of kaonic hydrogen in the SIDDHARTA experiment at DA{Phi}NE has provided a very tight constraint on K{sup -}p scattering length. Typically, these approaches predict a two pole structure of {Lambda}(1405), but the question is how precise one can determine the position of these poles relying on data at and above the anti KN threshold. Moreover, we apply our framework for the analysis of pion-nucleon scattering in chapter 3. There we show that the

Meson and baryon production in K/sup +/ and. pi. /sup +/ beam jets and quark-diquark cascade model

Energy Technology Data Exchange (ETDEWEB)

Kinoshita, Kisei [Kagoshima Univ. (Japan). Faculty of Education; Noda, Hujio; Tashiro, Tsutomu

1982-11-01

A quark-diquark cascade model which includes flavor dependence and resonance effect is studied. The inclusive distributions of vector and pseudoscalar mesons and octet baryons and antibaryons in K/sup +/ and ..pi../sup +/ beam jets are analyzed. The contribution of decuplet baryons to the octet baryon spectra is very important in meson beam jet. The effects of the asymmetric u- and anti s-quark distributions in K/sup +/ and the SU(6)-symmetry breaking for the produced octet baryon are discussed in connection with the ..pi../sup +//K/sup +/ beam ratio and other data.

Search for a Narrow Baryonic Resonance Decaying to $K^0_s p$ or $K^0_s \\bar{p}$ in Deep Inelastic Scattering at HERA

OpenAIRE

Aktas, A.; Andreev, V.; Anthonis, T.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Babaev, A.; Backovic, S.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Baumgartner, S.

2006-01-01

A search for a narrow baryonic resonance decaying to $K^0_s p$ or $K^0_s \\bar p$ is carried out in deep inelastic ep scattering with the H1 detector at HERA. Such a resonance could be a strange pentaquark \\thplns, evidence for which has been reported by several experiments. The $K^0_s p$ and $K^0_s \\bar p$ invariant mass distributions presented here do not show any significant peak in the mass range from threshold up to 1.7 GeV. Mass dependent upper limits on $\\sigma(ep \\to e \\thplf X)\\times ...

Inclusive charm production at HERA and charm content of the proton

Energy Technology Data Exchange (ETDEWEB)

Drees, M [Wisconsin Univ., Madison, WI (United States). Dept. of Physics; Godbole, R M [Istituto Nazionale di Fisica Nucleare, Frascati (Italy)

1995-05-01

The authors calculate the contribution to inclusive high transverse momentum (p{sub T}) charm production at HERA (hadron electron ring at large) from the excitation of charm in the photon. At large values of p{sub T} the results of such a calculation, in the structure function language, will be more reliable as it sums the large logs log(p{sub T}{sup 2}/m{sub C}{sup 2}), as opposed to calculating the contribution of the 2{yields}3 subprocesses in fixed order of perturbation theory. They find that this contribution is large and comparable to the contribution from {gamma}g fusion production of charm. Suitable cuts on the rapidity of the `away-side` large p{sub T} jet allow a very neat separation between the contributions from the excitation process and from pair-production. Including this excitation contribution the authors can reproduce the measured inclusive D{sup *} and {mu} cross-section measured by the ZEUS and H1 collaborations respectively, in a LO calculation.

Asymptotic energy scale factors for pseudoscalar meson scattering and charmed meson couplings

International Nuclear Information System (INIS)

Thews, R.L.

1977-01-01

Energy scale factors ν 0 for PP → PP scattering amplitudes are related via absence of exotic resonances of ratios of tensor to vector coupling strengths. These same ratios are extracted from FESR's for non-exotic reactions. The scale factors obtained are all of the order of 1.0 GeV 2 or less, indepedent of quantum numbers. This contradicts the expectations of dual amplitudes in which ν 0 =1/α', and trajectory slopes are smaller for charmed mesons. Decay widths for tensor mesons are predicted. An observed SU(3) violation for the ratio A 2 → KantiK/K** → Kπ is shown to be consistent with the FESR results. Charmed meson decays are predicted to be factors of 2 to 3 larger than those predicted by SU(4). (author)

Cross sections for charm production by neutrinos

Energy Technology Data Exchange (ETDEWEB)

Ushida, N [Aichi Univ. of Education, Kariya (Japan). Dept. of Physics; Kondo, T [Fermi National Accelerator Lab., Batavia, IL (USA); Fujioka, G; Fukushima, J; Takahashi, Y; Tatsumi, S; Yokoyama, C [Kobe Univ. (Japan). Dept. of Physics; Homma, Y; Tsuzuki, Y [Kobe Univ. (Japan). Coll. of Liberal Arts; Bahk, S

1983-02-03

The production of charmed particles has been measured using a hybrid emulsion spectrometer in the Fermilab wide-band neutrino beam. The relative cross section for charged current charmed particle production is sigma(v -> ..mu../sup -/c)/sigma(v -> ..mu../sup -/) = 6.5 +- 1.9/1.8%, and the energy dependence of the cross section is presented. One event with charm pair production was observed. A limit of sigma(v -> ..mu..canti c)/sigma(v -> ..mu..c) < 6% (90% CL) is found for the ratio of charged current pair and single charm production.

Associated charm production in neutrino-nucleus interactions

International Nuclear Information System (INIS)

Kayis-Topaksu, A.; Oenenguet, G.; van Dantzig, R.; de Jong, M.; Oldeman, R.G.C.; Gueler, M.; Koese, U.; Tolun, P.; Catanesi, M.G.; Muciaccia, M.T.; Winter, K.; Van de Vyver, B.; Vilain, P.; Wilquet, G.; Saitta, B.; Di Capua, E.; Ogawa, S.; Shibuya, H.; Hristova, I.R.; Kawamura, T.; Kolev, D.; Meinhard, H.; Panman, J.; Tsenov, R.; Uiterwijk, J.W.E.; Rozanov, A.; Zucchelli, P.; Goldberg, J.; Chikawa, M.; Song, J.S.; Yoon, C.S.; Kodama, K.; Ushida, N.; Aoki, S.; Hara, T.; Delbar, T.; Favart, D.; Gregoire, G.; Kalinin, S.; Makhlioueva, I.; Artamonov, A.; Khovansky, V.; Shamanov, V.; Tsukerman, I.; Gorbunov, P.; 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.; Fiorillo, G.; Marotta, A.; Migliozzi, P.; Scotto Lavina, L.; Strolin, P.; Tioukov, V.; Okusawa, T.; Dore, U.; Loverre, P.F.; Ludovici, L.; Rosa, G.; Santacesaria, R.; Satta, A.; Spada, F.R.; Barbuto, E.; Bozza, C.; Grella, G.; Romano, G.; Sirignano, C.; Sorrentino, S.; Sato, Y.; Tezuka, I.

2007-01-01

In this paper a search for associated charm production both in neutral and charged current ν-nucleus interactions is presented. The improvement of automatic scanning systems in the CHORUS experiment allows an efficient search to be performed in emulsion for short-lived particles. Hence a search for rare processes, like the associated charm production, becomes possible through the observation of the double charm-decay topology with a very low background. About 130000 ν interactions located in the emulsion target have been analysed. Three events with two charm decays have been observed in the neutral-current sample with an estimated background of 0.18±0.05. The relative rate of the associated charm cross-section in deep inelastic ν interactions, σ(c anti cν)/σ NC DIS =(3.62 +2.95 -2.42 (stat)±0.54(syst)) x 10 -3 has been measured. One event with two charm decays has been observed in charged-current ν μ interactions with an estimated background of 0.18±0.06 and the upper limit on associated charm production in charged-current interactions at 90% C.L. has been found to be σ(c anti cμ - )/σ CC -4 . (orig.)

Odd-parity baryons: progress and problems

International Nuclear Information System (INIS)

Cutkosky, R.E.

1981-01-01

The odd-parity baryons have provided a graveyard for many cherished ideas about hadrons. The simple quark shell model, with QCD-inspired phenomenological perturbations, is the only model able to describe the states with even partial qualitative success. There are also important unexplained residual dynamical effects. Resonance decays can be accounted for, provided the usual spectator model is abandoned. Better experimental data could help to sort out the many remaining puzzles

Baryons and baryonic matter in the large Nc and heavy quark limits

International Nuclear Information System (INIS)

Cohen, Thomas D.; Kumar, Nilay; Ndousse, Kamal K.

2011-01-01

This paper explores properties of baryons and finite density baryonic matter in an artificial world in which N c , the number of colors, is large and the quarks of all species are degenerate and much larger than Λ QCD . It has long been known that in large N c quantum chromodynamics (QCD), baryons composed entirely of heavy quarks are accurately described in the mean-field approximation. However, the detailed properties of baryons in the combined large N c and heavy-quark limits have not been fully explored. Here some basic properties of baryons are computed using a variational approach. At leading order in both the large N c and heavy-quark expansions the baryon mass is shown to be M baryon ≅N c M Q (1-0.054 26α-tilde s 2 ), where α-tilde s ≡N c α s . The baryon form factor is also computed. Baryonic matter, the analog of nuclear matter in this artificial world, should also be well described in the mean-field approximation. In the special case where all baryons have an identical spin-flavor structure, it is shown that in the formal heavy-quark and large N c limit interactions between baryons are strictly repulsive at low densities. The energy per baryon is computed in this limit and found to be exponentially small. It is shown that when the restriction to baryons with an identical spin-flavor structure is dropped, a phase of baryonic matter exists with a density of 2N f times that for the restricted case but with the same energy (where N f is the number of degenerate flavors). It is shown that this phase is at least metastable.

Geometrical scaling in charm structure function ratios

International Nuclear Information System (INIS)

Boroun, G.R.; Rezaei, B.

2014-01-01

By using a Laplace-transform technique, we solve the next-to-leading-order master equation for charm production and derive a compact formula for the ratio R c =F L cc ¯ /F 2 cc ¯ , which is useful for extracting the charm structure function from the reduced charm cross section, in particular, at DESY HERA, at small x. Our results show that this ratio is independent of x at small x. In this method of determining the ratios, we apply geometrical scaling in charm production in deep inelastic scattering (DIS). Our analysis shows that the renormalization scales have a sizable impact on the ratio R c at high Q 2 . Our results for the ratio of the charm structure functions are in a good agreement with some phenomenological models

JINR tau-charm factory design study

International Nuclear Information System (INIS)

Perel'shtejn, E.; Aleksandrov, V.; Antropov, V.

1993-01-01

The review on tau-charm factory in JINR (Dubna) is presented. The structure scheme of tau-charm factory is described. The problems on injection complex are discussed: the composition, the working regime and parameters. The magnetic lattice of a booster is described. A versatile magnet lattice is used in tau-charm collider. It can realize both conventional flat beam scheme and monochromatization scheme. The results of chromaticity correction in high emittance lattice are presented. The list of parameters of tau-charm collider is given. The technical proposal of magnetic elements of booster and collider and their power supplies is made, as well as RF power supply in collider and vacuum system in its periodic cell. 12 refs.; 12 figs.; 3 tabs

Decoupling of charm beyond leading order

OpenAIRE

Knechtli, Francesco; Korzec, Tomasz; Leder, Björn; Moir, Graham

2017-01-01

We study the effective theory of decoupling of a charm quark at low energies. We do this by simulating a model, QCD with two mass-degenerate charm quarks. At leading order the effective theory is a pure gauge theory. By computing ratios of hadronic scales we have direct access to the power corrections in the effective theory. We show that these corrections follow the expected leading behavior, which is quadratic in the inverse charm quark mass.

A tau-charm-factory at Argonne

International Nuclear Information System (INIS)

Norem, J.; Repond, J.

1994-01-01

In this paper we explore the possibility of building a tau-charm-factory at the Argonne National Laboratory. A tau-charm-factory is an e + e - collider with a center-of-mass energy between 3.0 GeV and 5.0 GeV and a luminosity of at least 1 x 10 33 cm -2 s -1 . Once operational, the facility will produce large samples of τ pairs, charm mesons, and charmonium with either negligible or well understood backgrounds. This will lead to high precision measurements in the second generation quark and the third generation lepton sectors that cannot be done at other facilities. Basic physical properties and processes, such as the tau neutrino mass, rare tau decays, charm decay constants, rare charm meson decays, neutral D 0 -- meson mixing, and many more will be studied with unique precision. An initial design of the collider including the injector system is described. The design shows that a luminosity of at least 1 x 10 33 cm -2 s -1 can be achieved over the entire center-of-mass energy range of the factory

Molecular dynamics simulation for the baryon-quark phase transition at finite baryon density

International Nuclear Information System (INIS)

Akimura, Y.; Maruyama, T.; Chiba, S.; Yoshinaga, N.

2005-01-01

We study the baryon-quark phase transition in the molecular dynamics (MD) of the quark degrees of freedom at finite baryon density. The baryon state at low baryon density, and the deconfined quark state at high baryon density are reproduced. We investigate the equations of state of matters with different u-d-s compositions. It is found that the baryon-quark transition is sensitive to the quark width. (orig.)

Observation of double charm production involving open charm in pp collisions at $\\sqrt{s}$=7 TeV

CERN Document Server

Aaij, R; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves Jr, A A; Amato, S; Amhis, Y; Anderson, J; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bates, A; Bauer, C; Bauer, Th; Bay, A; Bediaga, I; Belogurov, S; 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; Bird, T; 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; Britsch, M; Britton, T; Brook, N H; Brown, H; Büchler-Germann, A; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; 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; Cauet, Ch; 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; Contu, A; Cook, A; Coombes, M; Corti, G; Couturier, B; Cowan, G A; Currie, R; D'Ambrosio, C; David, P; David, P N Y; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Del Buono, L; Deplano, C; Derkach, D; Deschamps, O; Dettori, F; Dickens, J; Dijkstra, H; Diniz Batista, P; Domingo Bonal, F; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Dziurda, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisele, F; Eisenhardt, S; Ekelhof, R; Eklund, L; Elsasser, Ch; Elsby, D; Esperante Pereira, D; Falabella, A; 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; Francisco, O; 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; Gauld, R; 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; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hampson, T; Hansmann-Menzemer, S; Harji, R; Harnew, N; Harrison, J; Harrison, P F; Hartmann, T; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; 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; Kaballo, M; Kandybei, S; Karacson, M; Karbach, T M; Keaveney, J; Kenyon, I R; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kim, Y M; Knecht, M; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kruzelecki, K; Kucharczyk, M; Kudryavtsev, V; 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; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J -P; Lefèvre, 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; von Loeben, J; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Lu, H; Luisier, J; Mac Raighne, A; 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; Martinelli, M; Martinez Santos, D; Massafferri, A; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Maynard, B; Mazurov, A; McGregor, G; McNulty, R; Meissner, M; Merk, M; Merkel, J; Miglioranzi, S; Milanes, D A; Minard, M -N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Mylroie-Smith, J; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neufeld, N; Nguyen, A D; Nguyen-Mau, C; Nicol, M; Niess, V; Nikitin, N; Nikodem, T; Nomerotski, A; Novoselov, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, B 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; Petrolini, A; Phan, A; Picatoste Olloqui, E; Pie Valls, B; Pietrzyk, B; Pilař, T; Pinci, D; Plackett, R; Playfer, S; Plo Casasus, M; Polok, G; Poluektov, A; Polycarpo, E; Popov, D; Popovici, B; Potterat, C; Powell, A; 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; Richards, A; 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; Santamarina Rios, C; Santinelli, R; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Savrina, D; Schaack, P; Schiller, M; Schindler, H; Schleich, S; Schlupp, M; 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; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Skwarnicki, T; 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; 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; Tolk, S; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tsaregorodtsev, A; Tuning, N; Ubeda Garcia, M; Ukleja, A; Uwer, U; Vagnoni, V; Valenti, G; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; Velthuis, J J; Veltri, M; Viaud, B; Videau, I; Vieira, D; Vilasis-Cardona, X; Visniakov, J; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voss, H; Waldi, R; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; 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; Zangoli, M; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhong, L; Zvyagin, A

2012-01-01

The production of $J/\\psi$ mesons accompanied by open charm, and of pairs of open charm hadrons are observed in pp collisions at a centre-of-mass energy of 7 TeV using an integrated luminosity of $355pb^{-1}$ collected with the LHCb detector. Model independent measurements of absolute cross-sections are given together with ratios to the measured $J/\\psi$ and open charm cross-sections. The properties of these events are studied and compared to theoretical predictions.

Decays of J/psi (3100) to baryon final states

International Nuclear Information System (INIS)

Eaton, M.W.

1982-05-01

We present results for the decays of psi(3100) into baryon and hyperon final states. The sample studied here consists of 1.3 million produced psi decays. The decays into nonstrange baryons agree well with currently established results, but with better statistics. In addition, significant resonance formation in multibody final states is observed. The decay psi → anti ppγ, the first direct photon decay of the psi involving baryons in the final state, is presented and the theoretical implications of the decays are briefly explored. Several new decays of the psi involving strange baryons are explored, including the first observations of three body final states involving hyperons. The I-spin symmetry of the strong decay psi → baryons has clearly been observed. The reduced matrix elements for psi → B anti B are presented for final states of different SU(3) content. The B 8 anti B 8 results are in excellent agreement with the psi being an SU(3) singlet as are the results for psi → B 10 anti B 10 . We present the first evidence for the SU(3) violating decays of the type psi → B 8 anti B 10 + c.c.. Angular distributions for psi → B 8 anti B 8 are presented and compared with theoretical predictions. Statistics are limited, but the data tends to prefer other than a 1 + Cos 2 theta distribution

Strong decays of the 1 P and 2 D doubly charmed states

Science.gov (United States)

Xiao, Li-Ye; Lü, Qi-Fang; Zhu, Shi-Lin

2018-04-01

We perform a systematical investigation of the strong decay properties of the low-lying 1 P - and 2 D -wave doubly charmed baryons with the 3P0 quark pair creation model. The main predictions include: (i) in the Ξc c and Ωc c family, the 1 P ρ mode excitations with JP=1 /2- and 3 /2- should be the fairly narrow states, while, for the 1 P λ mode excitations, they are most likely to be moderate states with a width of Γ ˜100 MeV . (ii) The 2 Dρ ρ states mainly decay via emitting a heavy-light meson and the decay widths can reach several tens MeV if their masses are above the threshold of ΛcD or ΞcD , respectively. The 2 Dλ λ states may be broad states with a width of Γ >100 MeV .

Baryons and baryonic matter in four-fermion interaction models

International Nuclear Information System (INIS)

Urlichs, K.

2007-01-01

In this work we discuss baryons and baryonic matter in simple four-fermion interaction theories, the Gross-Neveu model and the Nambu-Jona-Lasinio model in 1+1 and 2+1 space-time dimensions. These models are designed as toy models for dynamical symmetry breaking in strong interaction physics. Pointlike interactions (''four-fermion'' interactions) between quarks replace the full gluon mediated interaction of quantum chromodynamics. We consider the limit of a large number of fermion flavors, where a mean field approach becomes exact. This method is formulated in the language of relativistic many particle theory and is equivalent to the Hartree-Fock approximation. In 1+1 dimensions, we generalize known results on the ground state to the case where chiral symmetry is broken explicitly by a bare mass term. For the Gross-Neveu model, we derive an exact self-consistent solution for the finite density ground state, consisting of a one-dimensional array of equally spaced potential wells, a baryon crystal. For the Nambu- Jona-Lasinio model we apply the derivative expansion technique to calculate the total energy in powers of derivatives of the mean field. In a picture akin to the Skyrme model of nuclear physics, the baryon emerges as a topological soliton. The solution for both the single baryon and dense baryonic matter is given in a systematic expansion in powers of the pion mass. The solution of the Hartree-Fock problem is more complicated in 2+1 dimensions. In the massless Gross-Neveu model we derive an exact self-consistent solution by extending the baryon crystal of the 1+1 dimensional model, maintaining translational invariance in one spatial direction. This one-dimensional configuration is energetically degenerate to the translationally invariant solution, a hint in favor of a possible translational symmetry breakdown by more general geometrical structures. In the Nambu-Jona-Lasinio model, topological soliton configurations induce a finite baryon number. In contrast

Baryons and baryonic matter in four-fermion interaction models

Energy Technology Data Exchange (ETDEWEB)

Urlichs, K.

2007-02-23

In this work we discuss baryons and baryonic matter in simple four-fermion interaction theories, the Gross-Neveu model and the Nambu-Jona-Lasinio model in 1+1 and 2+1 space-time dimensions. These models are designed as toy models for dynamical symmetry breaking in strong interaction physics. Pointlike interactions (''four-fermion'' interactions) between quarks replace the full gluon mediated interaction of quantum chromodynamics. We consider the limit of a large number of fermion flavors, where a mean field approach becomes exact. This method is formulated in the language of relativistic many particle theory and is equivalent to the Hartree-Fock approximation. In 1+1 dimensions, we generalize known results on the ground state to the case where chiral symmetry is broken explicitly by a bare mass term. For the Gross-Neveu model, we derive an exact self-consistent solution for the finite density ground state, consisting of a one-dimensional array of equally spaced potential wells, a baryon crystal. For the Nambu- Jona-Lasinio model we apply the derivative expansion technique to calculate the total energy in powers of derivatives of the mean field. In a picture akin to the Skyrme model of nuclear physics, the baryon emerges as a topological soliton. The solution for both the single baryon and dense baryonic matter is given in a systematic expansion in powers of the pion mass. The solution of the Hartree-Fock problem is more complicated in 2+1 dimensions. In the massless Gross-Neveu model we derive an exact self-consistent solution by extending the baryon crystal of the 1+1 dimensional model, maintaining translational invariance in one spatial direction. This one-dimensional configuration is energetically degenerate to the translationally invariant solution, a hint in favor of a possible translational symmetry breakdown by more general geometrical structures. In the Nambu-Jona-Lasinio model, topological soliton configurations induce a finite baryon

Search for a Narrow Baryonic Resonance Decaying to $K^0_s p$ or $K^0_s \\bar{p}$ in Deep Inelastic Scattering at HERA

CERN Document Server

Aktas, A.; Anthonis, T.; Antunovic, B.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Babaev, A.; Backovic, S.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Baumgartner, S.; Becker, J.; Beckingham, M.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, N.; Bizot, J.C.; Boenig, M.-O.; Boudry, V.; Bracinik, J.; Brandt, G.; Brisson, V.; Bruncko, D.; Busser, F.W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Contreras, J.G.; Coughlan, J.A.; Cox, B.E.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Dau, W.D.; Daum, K.; de Boer, Y.; Delcourt, B.; Del Degan, M.; De Roeck, A.; De Wolf, E.A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, Guenter; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Eliseev, A.; Elsen, E.; Essenov, S.; Falkewicz, A.; Faulkner, P.J.W.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Finke, L.; Fleischer, M.; Flucke, G.; Fomenko, A.; Franke, G.; Frisson, T.; Gabathuler, E.; Garutti, E.; Gayler, J.; Gerlich, C.; Ghazaryan, Samvel; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Grab, C.; Greenshaw, T.; Gregori, M.; Grell, B.R.; Grindhammer, G.; Gwilliam, C.; Haidt, D.; Hajduk, L.; Hansson, M.; Heinzelmann, G.; Henderson, R.C.W.; Henschel, H.; Herrera, G.; Hildebrandt, M.; Hiller, K.H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Hreus, T.; Hussain, S.; Ibbotson, M.; Ismail, M.; Jacquet, M.; Janauschek, L.; Janssen, X.; Jemanov, V.; Jonsson, L.; Johnson, D.P.; Jung, Andreas Werner; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I.R.; Kiesling, Christian M.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knies, G.; Knutsson, A.; Korbel, V.; Kostka, P.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Kruger, K.; Landon, M.P.J.; Lange, W.; Lastovicka-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Lobodzinska, E.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.-I.; Lueders, H.; Luke, D.; Lux, T.; Lytkin, L.; Makankine, A.; Malden, N.; Malinovski, E.; Mangano, S.; Marage, P.; Marshall, R.; Marti, L.; Martisikova, M.; Martyn, H.-U.; Maxfield, S.J.; Mehta, A.; Meier, K.; Meyer, A.B.; Meyer, H.; Meyer, J.; Michels, V.; Mikocki, S.; Milcewicz-Mika, I.; Milstead, D.; Mladenov, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J.V.; Mozer, Matthias Ulrich; Muller, K.; Murin, P.; Nankov, K.; Naroska, B.; Naumann, Th.; Newman, Paul R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J.E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Papadopoulou, T.; Pascaud, C.; Patel, G.D.; Peng, H.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Pitzl, D.; Placakyte, R.; Portheault, B.; Povh, B.; Prideaux, P.; Rahmat, A.J.; Raicevic, N.; Reimer, P.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D.P.C.; Sauvan, E.; Schatzel, S.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schoning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shaw-West, R.N.; Sheviakov, I.; Shtarkov, L.N.; Sloan, T.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, Arnd E.; Steder, M.; Stella, B.; Stiewe, J.; Stoilov, A.; Straumann, U.; Sunar, D.; Tchoulakov, V.; Thompson, Graham; Thompson, P.D.; Toll, T.; Tomasz, F.; Traynor, D.; Truol, P.; Tsakov, I.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, K.; Urban, Marcel; Usik, A.; Utkin, D.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Veelken, C.; Vinokurova, S.; Volchinski, V.; Wacker, K.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Wessels, M.; Wessling, B.; Wissing, Ch.; Wolf, R.; Wunsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zhu, Y.C.; Zimmermann, J.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.

2006-01-01

A search for a narrow baryonic resonance decaying to $K^0_s p$ or $K^0_s \\bar p$ is carried out in deep inelastic ep scattering with the H1 detector at HERA. Such a resonance could be a strange pentaquark \\thplns, evidence for which has been reported by several experiments. The $K^0_s p$ and $K^0_s \\bar p$ invariant mass distributions presented here do not show any significant peak in the mass range from threshold up to 1.7 GeV. Mass dependent upper limits on $\\sigma(ep \\to e \\thplf X)\\times BR(\\thplf \\to K^0 p)$ are obtained at the 95% confidence level.

A Higgs at 125.1 GeV and baryon mass spectra derived from a Common U(3) Lie group framework

DEFF Research Database (Denmark)

Trinhammer, Ole; Bohr, Henrik; Jensen, Mogens O Stibius

2015-01-01

Baryons are described by a Hamiltonian on an intrinsic U(3) Lie group configuration space with electroweak degrees of freedom originating in specific Bloch wave factors. By opening the Bloch degrees of freedom pairwise via a U(2) Higgs mechanism, the strong and electroweak energy scales become...... related to yield the Higgs mass 125.085+/-0.017 GeV and the usual gauge boson masses. From the same Hamiltonian we derive both the relative neutron to proton mass ratio and the N and Delta mass spectra. All compare rather well with the experimental values. We predict neutral flavour baryon singlets...... to be sought for in negative pions scattering on protons or in photoproduction on neutrons and in invariant mass like Σ+c(2455)D- from various decays above the open charm threshold, e.g. at 4499, 4652 and 4723 MeV. The fundamental predictions are based on just one length scale and the fine structure coupling...

Lecture I. Introduction to charm

International Nuclear Information System (INIS)

Anon.

1978-01-01

Lectures are given on some manifestations of charm and some characteristics of the charmed particle. Various points of view in a cultural orientation, leptons, reasons for a belief in quarks, gauge theories of weak and electromagnetic and strong interactions, and lastly the viewpoint that there is not a systhesis at hand, but instead chaos are treated. 6 references

A relativized quark model for radiative baryon transitions

International Nuclear Information System (INIS)

Warns, M.; Schroeder, H.; Pfeil, W.; Rollnik, H.

1989-03-01

In this paper we investigate the electromagnetic form factors of baryons and their resonances using the framework of a relativized constituent quark model. Beyond the usual single-quark transition ansatz, we incorporate relativistic corrections which are well-determined by the intrinsic strong interaction and confinement forces between the quarks. Furthermore we separate off for the compound three-quark system the relativistic center-of-mass motion by an approximately Lorentz-invariant approach. In this way for the first time recoil effects could be explicitly studied. Using the harmonic oscillator wavefunctions with the configuration mixing as derived in the Isgur-Karl model, after restoring gauge invariance our relativized interaction hamiltonian can be used to calculate the transversely and longitudinally polarized photon transition form factors of the baryons. (orig.)

Novel QCD physics at NICA

Energy Technology Data Exchange (ETDEWEB)

Brodsky, Stanley J. [Stanford University, SLAC National Accelerator Laboratory, Stanford, CA (United States)

2016-08-15

The NICA collider project at the Joint Institute for Nuclear Research in Dubna will have the capability of colliding protons, polarized deuterons, and nuclei at an effective nucleon-nucleon center-of-mass energy in the range √(s{sub NN}) = 4 - 11 GeV. I briefly survey a number of novel hadron physics processes which can be investigated at the NICA collider. The topics include the formation of exotic heavy-quark resonances near the charm and bottom thresholds, intrinsic strangeness, charm, and bottom phenomena, hidden-color degrees of freedom in nuclei, color transparency, single-spin asymmetries, the RHIC baryon anomaly, and non-universal antishadowing. (orig.)

General solution of superconvergent sum rules for scattering of I=1 reggeons on baryons

International Nuclear Information System (INIS)

Grigoryan, A.A.; Khachatryan, G.N.

1986-01-01

Superconvergent sum rules for reggeon-particle scattering are applied to scattering of reggeons α i (i=π, ρ, A 2 ) with isospin I=1 on baryons with strangeness S=-1. The saturation scheme of these sum rules is determined on the basis of experimental data. Two series of baryon resonances with arbitrary isospins I and spins J=I+1/2 and J=I-1/2 are predicted. A general solution for vertices of interaction of these resonances with α i is found. Predictions for coupling vertices B α i B'(B, B'=Λ, Σ, Σ * ) agree well with the experiment. It is shown that the condition of sum rules saturation by minimal number of resonances brings to saturation schemes resulting from experimental data. A general solution of sum rules for scattering of α i reggeons on Ξ and Ω hyperons is analyzed

Hidden charm molecules in a finite volume

International Nuclear Information System (INIS)

Albaladejo, M.; Hidalgo-Duque, C.; Nieves, J.; Oset, E.

2014-01-01

In the present paper we address the interaction of charmed mesons in hidden charm channels in a finite box. We use the interaction from a recent model based on heavy quark spin symmetry that predicts molecules of hidden charm in the infinite volume. The energy levels in the box are generated within this model, and several methods for the analysis of these levels ("inverse problem") are investigated. (author)

Measurement of charm and beauty production in deep inelastic scattering at HERA

International Nuclear Information System (INIS)

Roloff, Philipp

2011-12-01

In this thesis two measurements of heavy quark production in deep inelastic scattering at HERA are presented. Cross sections for the production of heavy quarks can be calculated in quantum chromodynamics (QCD). The heavy quark masses represent hard scales, which allow to apply perturbative methods. Charm production has been measured with the ZEUS detector using an integrated luminosity of 120 pb -1 . The hadronic decay channels D + → K 0 S π + , Λ + c → pK 0 S and Λ + c → Λπ + were reconstructed. The presence of a neutral strange hadron in the final state reduces the combinatorial background and extends the measured sensitivity into the region p T (D + , Λ + c ) T 2 (D + ), η(D + ), Q 2 and x for the production of D + mesons are in reasonable agreement with predictions from perturbative QCD. The fraction of c quarks hadronising into Λ + c baryons was extracted from a combination of both investigated Λ + c decay channels. The result is consistent with a previous measurement in the photoproduction regime and with the average e + e - value. The production of charm and beauty quarks has been measured with the ZEUS detector using the data collected between 2004 and 2007. This data sample corresponds to an integrated luminosity of 354 pb -1 . The charm and beauty contents in events with a jet were determined using the decay-length significance and invariant mass of the reconstructed secondary decay vertices. Differential cross sections in E jet T , η jet , Q 2 and x are in reasonable agreement with predictions for perturbative QCD. The open charm and beauty contributions to the inclusive proton structure function F 2 were extracted from double differential cross sections in x and Q 2 . The obtained F c anti c 2 and F b anti b 2 values are in good agreement with previous measurements and theoretical predictions. This measurement represents the most precise determination of F b anti b 2 at the HERA collider in a large part of the accessible phase space

Open charm hadroproduction and the charm content of the proton

Energy Technology Data Exchange (ETDEWEB)

Kniehl, Bernd A.; Kramer, Gustav [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Schienbein, Ingo [Grenoble 1 Univ. (France). Laboratoire de Physique Subatomique et de Cosmologie]|[CNRS/IN2P3, Grenoble (France). Institut National Polytechnique de Grenoble; Spiesberger, Hubert [Mainz Univ. (Germany). Inst. fuer Physik

2009-01-15

We advocate charmed-hadron inclusive hadroproduction as a laboratory to probe intrinsic charm (IC) inside the colliding hadrons. Working at next-to-leading order in the general-mass variable-flavor-number scheme endowed with non-perturbative fragmentation functions recently extracted from a global fit to e{sup +}e{sup -} annihilation data from KEKB, CESR, and LEP1, we first assess the sensitivity of Tevatron data of D{sup 0}, D{sup +}, and D{sup *+} inclusive production to the IC parameterizations provided by Pumplin et al. We then argue that similar data from pp collisions at RHIC would have the potential to discriminate between different IC models provided they reach out to sufficiently large values of transverse momentum. (orig.)

Excited baryon program at the Bonn electron stretcher accelerator ELSA

International Nuclear Information System (INIS)

Menze, D.

1989-01-01

The Bonn electron stretcher accelerator ELSA is the first of a new generation of continuous beam machines in the GeV region. It is qualified for experiments with tagged photons and with polarized electrons on polarized nucleons to investigate the electromagnetic properties of excited baryon resonances

The semileptonic decays of charmed particles

International Nuclear Information System (INIS)

Nabavi, R.P.; Pham, X.Y.; Cottingham, W.N.

1977-01-01

A general formalism is developped for analyzing the semileptonic decays of charmed particles in terms of helicity amplitudes. This formalism is to the D and F mesons, and a simple experimental test for the V+-A coupling of the charmed quark, is proposed

A determination of the charm content of the proton

Energy Technology Data Exchange (ETDEWEB)

Ball, Richard D. [University of Edinburgh, The Higgs Centre for Theoretical Physics, Edinburgh (United Kingdom); Bertone, Valerio; Bonvini, Marco; Hartland, Nathan P.; Rojo, Juan; Rottoli, Luca [University of Oxford, Rudolf Peierls Centre for Theoretical Physics, Oxford (United Kingdom); Carrazza, Stefano [CERN, Theory Division, Geneva (Switzerland); Forte, Stefano [Universita di Milano, Dipartimento di Fisica, Milan (Italy); INFN, Sezione di Milano, Milan (Italy); Guffanti, Alberto [Universita di Torino, Dipartimento di Fisica, Turin (Italy); INFN, Sezione di Torino, Turin (Italy); Collaboration: NNPDF Collaboration

2016-11-15

We present an unbiased determination of the charm content of the proton, in which the charm parton distribution function (PDF) is parametrized on the same footing as the light quarks and the gluon in a global PDF analysis. This determination relies on the NLO calculation of deep-inelastic structure functions in the FONLL scheme, generalized to account for massive charm-initiated contributions. When the EMC charm structure function dataset is included, it is well described by the fit, and PDF uncertainties in the fitted charm PDF are significantly reduced. We then find that the fitted charm PDF vanishes within uncertainties at a scale Q ∝ 1.6 GeV for all x charm PDF at large x >or similar 0.1 and low scales does not vanish, but rather has an ''intrinsic'' component, very weakly scale dependent and almost independent of the value of m{sub c}, carrying less than 1% of the total momentum of the proton. The uncertainties in all other PDFs are only slightly increased by the inclusion of fitted charm, while the dependence of these PDFs on m{sub c} is reduced. The increased stability with respect to m{sub c} persists at high scales and is the main implication of our results for LHC phenomenology. Our results show that if the EMC data are correct, then the usual approach in which charm is perturbatively generated leads to biased results for the charm PDF, though at small x this bias could be reabsorbed if the uncertainty due to the charm mass and missing higher orders were included. We show that LHC data for processes, such as high p{sub T} and large rapidity charm pair production and Z + c production, have the potential to confirm or disprove the implications of the EMC data. (orig.)

Baryon Spectroscopy Through Partial-Wave Analysis and Meson Photoproduction

International Nuclear Information System (INIS)

Manley, D. Mark

2016-01-01

The principal goal of this project is the experimental and phenomenological study of baryon spectroscopy. The PI's group consists of himself and three graduate students. This final report summarizes research activities by the PI's group during the period 03/01/2015 to 08/14/2016. During this period, the PI co-authored 11 published journal papers and one proceedings article and presented three invited talks. The PI's general interest is the investigation of the baryon resonance spectrum up to masses of ~ 2 GeV. More detail is given on two research projects: Neutral Kaon Photoproduction and Partial-Wave Analyses of γp → η p, γn → η n, and γp → K"+ Λ.

Search for exotic baryons in 800 GeV/c pp → pX

Science.gov (United States)

Christian, D. C.; Felix, J.; Gottschalk, E. E.; Gutierrez, G.; Hartouni, E. P.; Knapp, B. C.; Kreisler, M. N.; Moreno, G.; Reyes, M. A.; Sosa, M.; Wang, M. H. L. S.; Wehmann, A.

2006-05-01

We present preliminary results of the search for the pentaquark candidates Θ(1540) and Ξ(1862) using data from Fermilab experiment E690 in the reaction pp → pX at 800 GeV/c. We find that production of pentaquark resonances is heavily suppressed with respect to the production of normal baryon and antibaryon resonances.

Search for exotic baryons in 800 GeV/c pp {yields} pX

Energy Technology Data Exchange (ETDEWEB)

Christian, D C [Fermi National Accelerator Laboratory, Batavia, Illinois (United States); Felix, J [University of Guanajuato, Leon, Guanajuato (Mexico); Gottschalk, E E [Fermi National Accelerator Laboratory, Batavia, Illinois (United States); Gutierrez, G [Fermi National Accelerator Laboratory, Batavia, Illinois (United States); Hartouni, E P [Lawrence Livermore National Laboratory, Livermore, California (United States); Knapp, B C [Columbia University, Nevis Laboratory, New York (United States); Kreisler, M N [University of Massachusetts, Amherst, Massachusetts (United States); Moreno, G [University of Guanajuato, Leon, Guanajuato (Mexico); Reyes, M A [University of Guanajuato, Leon, Guanajuato (Mexico); Sosa, M [University of Guanajuato, Leon, Guanajuato (Mexico); Wang, M H L S [Fermi National Accelerator Laboratory, Batavia, Illinois (United States); Wehmann, A [Fermi National Accelerator Laboratory, Batavia, Illinois (United States)

2006-05-15

We present preliminary results of the search for the pentaquark candidates {theta}(1540) and {xi}(1862) using data from Fermilab experiment E690 in the reaction pp {yields} p{sup X} at 800 GeV/c. We find that production of pentaquark resonances is heavily suppressed with respect to the production of normal baryon and antibaryon resonances.

Experimental issues in high-sensitivity charm experiments

International Nuclear Information System (INIS)

Appel, J.A.

1994-07-01

Progress in the exploration of charm physics at fixed target experiments has been prodigious over the last 15 years. The issue before the CHARM2000 Workshop is whether and how this progress can be continued beyond the next fixed target run. An equivalent of 10 8 fully reconstructed charm decays has been selected as a worthy goal. Underlying all this is the list of physics questions which can be answered by pursuing charm in this way. This paper reviews the experimental issues associated with making this next step. It draws heavily on the experience gathered over the period of rapid progress and, at the end, poses the questions of what is needed and what choices may need to be made

INP studies for a Tau-Charm Factory

International Nuclear Information System (INIS)

Skrinsky, A.

1994-01-01

This paper presents the results of studies undertaken at INP of options for a Tau Charm Factory. Three different beam options have been studied. First is a 'round beam option', allowing axially symmetric beams which yield high tau-pair productivity. The second option involves monochromatic beams, which enhances productivity for narrow c bar c states, gives good tau pair productions in a clean manner, and has a good resonant-to-nonresonant ratio. The third option allows longitudinal polarization, should it prove to be interesting. It is an easy option to implement because it only involves polarized electrons. Work on some of these options is described in terms of experiments on the VEPP-2 device

A Determination of the Charm Content of the Proton

CERN Document Server

Ball, Richard D.; Bonvini, Marco; Carrazza, Stefano; Forte, Stefano; Guffanti, Alberto; Hartland, Nathan P.; Rojo, Juan; Rottoli, Luca

2016-01-01

We present an unbiased determination of the charm content of the proton, in which the charm parton distribution function (PDF) is parametrized on the same footing as the light quarks and the gluon in a global PDF analysis. This determination relies on the calculation of deep-inelastic structure functions in the FONLL scheme, generalized to account for massive charm-initiated contributions. In contrast to the usual situation in which the charm PDF is assumed to be generated perturbatively by pair radiation off gluons and light quarks, vanishing at a scale set by the value of the charm mass m_c, we find that the fitted charm PDF vanishes within uncertainties at a scale Q~1.5 GeV for all x~0.1 and low scales does not vanish, but rather has an "intrinsic" component, very weakly scale dependent and almost independent of the value of m_c, carrying about 1% of the total momentum of the proton. The uncertainties in all other PDFs are only slightly increased by the inclusion of fitted charm, while the dependence of th...

Observation of double charm production at LHCb

CERN Multimedia

CERN. Geneva

2012-01-01

The production of J/ψ together with an open charm meson, and double open charm production are observed in proton-proton collisions at centre-of-mass energy of 7 TeV using an integrated luminosity of 355 pb−1 collected with the LHCb detector. Model independent estimates of absolute cross-sections are given together with ratios to the measured J/ψ and open charm cross-sections. The properties of these events are studied and compared to theoretical predictions.

Parallel science and engineering applications the Charm++ approach

CERN Document Server

Kale, Laxmikant V

2016-01-01

Developed in the context of science and engineering applications, with each abstraction motivated by and further honed by specific application needs, Charm++ is a production-quality system that runs on almost all parallel computers available. Parallel Science and Engineering Applications: The Charm++ Approach surveys a diverse and scalable collection of science and engineering applications, most of which are used regularly on supercomputers by scientists to further their research. After a brief introduction to Charm++, the book presents several parallel CSE codes written in the Charm++ model, along with their underlying scientific and numerical formulations, explaining their parallelization strategies and parallel performance. These chapters demonstrate the versatility of Charm++ and its utility for a wide variety of applications, including molecular dynamics, cosmology, quantum chemistry, fracture simulations, agent-based simulations, and weather modeling. The book is intended for a wide audience of people i...

Baryon stopping and strangeness baryon production in a parton cascade model

International Nuclear Information System (INIS)

Nara, Yasushi

1999-01-01

A parton cascade model which is based on pQCD incorporating hard partonic scattering and dynamical hadronization scheme describes the space-time evolution of parton/hadron system produced by ultra-relativistic nuclear collisions. Hadron yield, baryon stopping and transverse momentum distribution are calculated and compared with experimental data at SPS energies. Using new version of parton cascade code VNI in which baryonic cluster formation is implemented, we calculate the net baryon number distributions and Λ yield. It is found that baryon stopping behavior at SPS energies is well accounted for within the parton cascade picture. As a consequence of the production of the baryon (u and d quark) rich parton matter, parton coalescence naturally explains the enhanced yield of Λ particle which has been observed in experiment. (author)

LHCb: Measuring $CP$ Violation in $\\Lambda_{c}^{+}$ Decays at LHCb

CERN Multimedia

Pearce, A

2013-01-01

An ongoing analysis of a measurement of CP violation in decays of the charmed baryon $\\Lambda_{c}^{+}$, using the full $3\\mathrm{fb}^{-1}$ of data collected by LHCb in 2011 and 2012, is presented. The detection asymmetry of the final states is considered, leading to the use of the narrow $p\\phi$ and $pK_{s}^{0}$ resonances in the $pK^{+}K^{-}$ and $p\\pi^{+}\\pi^{-}$ phase spaces, respectively.

From hidden charm to explicit charm. A review of the last progress in high energy physics

International Nuclear Information System (INIS)

Jacob, M.

1978-01-01

The last new developments in high energy physics are reviewed with these successive discoveries: in 1973 a new mode of interaction, the interaction through neutral currents; in 1974 new particles whose properties, first of all surprizing, today are simply associated with their hidden charm; in 1976 charmed particles which, like interactions through neutral currents, can be scheduled within the scope of theoretical models unifying the electromagnetic and weak interactions; in 1977 particles even more surprizing than their opposite numbers of 1974. 'Quark', charm, colour... the present day vocabulary of particles physics is displayed within the scope of an analysis of the structure of particles such as the proton, which are today far from being elementary [fr

Charm production in pp interactions at 70 GeV/c

International Nuclear Information System (INIS)

Coca, C.; Popescu, S.; Kusko, C.

1997-01-01

The cross section for charm production in pp interaction at the Serpukhov accelerator is estimated. The selection of the charm candidates (events with C1, C3, V2 decays) was done in the charm box 5 x 5 mm 2 by scanning the pictures from the vertex detector (a rapid cycling liquid hydrogen bubble chamber) of the set-up SVD-Vertex Detector Spectrometer. For the cross section determination the efficiency of the visible charm decay registration in the charm box region is taken into account. The cross section for charm production is going to be evaluated. An active solid target is foreseen to be used at SVD-upgrade (SVD2-set up). (authors)

Design of the micro vertex detector of the CBM experiment. Development of a detector response model and feasibility studies of open charm measurement

International Nuclear Information System (INIS)

Dritsa, Christina Anna

2011-01-01

The PhD addresses the feasibility of reconstructing open charm mesons with the Compressed Baryonic Matter experiment, which will be installed at the FAIR accelerator complex at Darmstadt/Germany. The measurements will be carried out by means of a dedicated Micro Vertex Detector (MVD), which will be equipped with CMOS Monolithic Active Pixel Sensors (MAPS). The feasibility of reconstructing the particles with a proposed detector setup was studied. To obtain conclusive results, the properties of a MAPS prototype were measured in a beam test at the CERN-SPS accelerator. Based on the results achieved, a dedicated simulation software for the sensors was developed and implemented into the software framework of CBM (CBMRoot). Simulations on the reconstruction of D 0 -mesons were carried out. It is concluded that the reconstruction of those particles is possible. The PhD introduces the physics motivation of doing open charm measurements, represents the results of the measurements of MAPS and introduces the innovative simulation model for those sensors as much as the concept and results of simulations of the D 0 reconstruction.

A tau -- charm -- factory at Argonne

International Nuclear Information System (INIS)

Berger, E.; Fields, T.; Grosnick, D.; Norem, J.; Repond, J.; Schoessow, P.

1994-01-01

Depending on the beam energy setting, the τ -- charm -- factory will be optimized to study physics with τ leptons, with charmed mesons, or with charmonium states. This report gives a short overview of the physics of these topics. Also discussed are the detectors and the costs associated with this project

Rare beauty and charm decays

International Nuclear Information System (INIS)

Blake, T.

2016-01-01

Rare beauty and charm decays can provide powerful probes of physics beyond the Standard Model. These proceedings summarise the latest measurements of rare beauty and charm decays from the LHCb experiment at the end of Run 1 of the LHC. Whilst the majority of the measurements are consistent with SM predictions, small differences are seen in the rate and angular distribution of b → sℓ"+ℓ"− decay processes.

A cross section measurement of charm hyperons Ξc+ and Ξc0 in 250 GeV p/K/π-nucleon interactions

International Nuclear Information System (INIS)

Francisco, J.; Vergara, A.

1995-01-01

Fermilab Experiment 769 used a charge-selected, hadron beam of mean energy 250 GeV/c, composed of pions, kaons, and protons, impinging on beryllium, aluminum, copper and tungsten targets. Using a sample of approximately 4000 Ξ s - → Λ 0 π - decays, measurements of the charm baryon forward cross sections times branching ratio π ± N → Ξ c + X and π ± N → Ξ c 0 X are presented. Upper limits on α x BR are also determined for the states Ξ c + → Ξ s - π + π + and Ξ c 0 → Ξ s - π + produced in (p, π + , π - , K + , K - )-nucleon interactions

Baryon Spectroscopy Through Partial-Wave Analysis and Meson Photoproduction

Energy Technology Data Exchange (ETDEWEB)

Manley, D. Mark [Kent State Univ., Kent, OH (United States)

2016-09-08

The principal goal of this project is the experimental and phenomenological study of baryon spectroscopy. The PI's group consists of himself and three graduate students. This final report summarizes research activities by the PI's group during the period 03/01/2015 to 08/14/2016. During this period, the PI co-authored 11 published journal papers and one proceedings article and presented three invited talks. The PI's general interest is the investigation of the baryon resonance spectrum up to masses of ~ 2 GeV. More detail is given on two research projects: Neutral Kaon Photoproduction and Partial-Wave Analyses of γp → η p, γn → η n, and γp → K⁺ Λ.

Searching for baryons

International Nuclear Information System (INIS)

Majumdar, Subhabrata

2015-01-01

The current precision cosmological measurements, in agreement with big bang nucleosynthesis studies, tell us that approximately 95 percent of the Universe is 'dark' and only 5 percent of the Universe is 'visible' which comprises of baryons. However, observations reveal only a small fraction of this baryon budget. A key cosmological question arises as to 'where are these missing baryons?'. Simulations and past observations suggest that some of these are in the diffuse cosmic web. Recently, they have been observed, and speculated, to be hiding in the outskirts of massive halos, from Milky Way type galaxies to clusters. Upcoming surveys have the potential to unravel the mystery of the missing baryons. (author)

Baryon spectroscopy. Recent results from the CBELSA/TAPS experiment at ELSA

Energy Technology Data Exchange (ETDEWEB)

Hartmann, Jan [HISKP, Universitaet Bonn (Germany); Collaboration: CBELSA/TAPS-Collaboration

2016-07-01

One of the remaining challenges within the standard model is to gain a good understanding of QCD in the non-perturbative regime. A key step towards this aim is baryon spectroscopy, investigating the spectrum and the properties of baryon resonances. To gain access to resonances with small πN partial width, photoproduction experiments provide essential information. Partial wave analyses need to be performed to extract the contributing resonances. Here, a complete experiment is required to unambiguously determine the contributing amplitudes. This involves the measurement of carefully chosen single and double polarization observables. The CBELSA/TAPS experiment with a longitudinally or transversely polarized target and an energy tagged, linearly or circularly polarized photon beam allows the measurement of a large set of polarization observables. Due to its good energy resolution, high detection efficiency for photons, and the nearly complete solid angle coverage it is ideally suited for the measurement of photoproduction of neutral mesons decaying into photons. In this talk recent results for various double polarization observables in single- and multi-meson final states are presented, and their impact on the partial wave analysis are discussed.

Disentanglement of Electromagnetic Baryon Properties

Science.gov (United States)

Sadasivan, Daniel; Doring, Michael

2017-01-01

Through recent advances in experimental techniques, the precise extraction of the spectrum of baryonic resonances and their properties becomes possible. Helicity couplings at the resonance pole are fundamental parameters describing the electromagnetic properties of resonances and enabling the comparison of theoretical models with data. We have extracted them from experiments carried out at Jefferson Lab and other facilities using a multipole analysis within the Julich-Bonn framework. Special attention has been paid to the uncertainties and correlations of helicity couplings. Using the world data on the reaction γp -> ηp , we have calculated, for the first time, the covariance matrix. Our results are useful in several ways. They quantify uncertainties but also correlations of helicity couplings. Second, they can tell us quantitatively how useful a given polarization measurement is. Third, they can tell us how the measurement of a new observable would constrain and disentangle the resonance properties which could be helpful in the design of new experiments. Finally, on the subject of the missing resonance problem, model selection techniques and statistical tests allow us to quantify the significance of whether a resonance exists. Supported by NSF CAREER Grant No. PHY-1452055, NSF PIF Grant No. 1415459, by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177, and by Research Center Julich through the HPC grant jikp07.

Observation of the Cabibbo-suppressed charmed baryon decay {Lambda}{sub {ital c}}{sup +}{r_arrow}{ital p}{phi}

Energy Technology Data Exchange (ETDEWEB)

Alexander, J.P.; Bebek, C.; Berger, B.E.; Berkelman, K.; Bloom, K.; Browder, T.E.; Cassel, D.G.; Cho, H.A.; Coffman, D.M.; Crowcroft, D.S.; Dickson, M.; Drell, P.S.; Dumas, D.J.; Ehrlich, R.; Elia, R.; Gaidarev, P.; Garcia-Sciveres, M.; Gittelman, B.; Gray, S.W.; Hartill, D.L.; Heltsley, B.K.; Henderson, S.; Jones, C.D.; Jones, S.L.; Kandaswamy, J.; Katayama, N.; Kim, P.C.; Kreinick, D.L.; Lee, T.; Liu, Y.; Ludwig, G.S.; Masui, J.; Mevissen, J.; Mistry, N.B.; Ng, C.R.; Nordberg, E.; Patterson, J.R.; Peterson, D.; Riley, D.; Soffer, A.; Avery, P.; Freyberger, A.; Lingel, K.; Prescott, C.; Rodriguez, J.; Yang, S.; Yelton, J.; Brandenburg, G.; Cinabro, D.; Liu, T.; Saulnier, M.; Wilson, R.; Yamamoto, H.; Bergfeld, T.; Eisenstein, B.I.; Ernst, J.; Gladding, G.E.; Gollin, G.D.; Palmer, M.; Selen, M.; Thaler, J.J.; Edwards, K.W.; McLean, K.W.; Ogg, M.; Bellerive, A.; Britton, D.I.; Hyatt, E.R.; Janicek, R.; MacFarlane, D.B.; Patel, P.M.; Spaan, B.; Sadoff, A.J.; Ammar, R.; Baringer, P.; Bean, A.; Besson, D.; Coppage, D.; Copty, N.; Davis, R.; Hancock, N.; Kotov, S.; Kravchenko, I.; Kwak, N.; Kubota, Y.; Lattery, M.; Momayezi, M.; Nelson, J.K.; Patton, S.; Poling, R.; Savinov, V.; Schrenk, S.; Wang, R.; Alam, M.S.; Kim, I.J.; Ling, Z.; Mahmood, A.H.; ONeill, J.J.; Severini, H.; Sun, C.R.; Wappler, F.; Crawford, G.; Fulton, R.; Fujino, D.; Gan, K.K.; Honscheid, K.; Kagan, H.; Kass, R.; Lee, J.; Sung, M.; White, C.; Wolf, A.; Zoeller, M.M.; Fu, X.; Nemati, B.; Ross, W.R.; Skubic, P.; Wood, M.; Bishai, M.; Fast, J.; Gerndt, E.; Hinson, J.W.; Miao, T.; Miller, D.H.; Modesitt, M.; Shibata, E.I.; Shipsey, I.P.; Wang, P.N.; Gibbons, L.; Johnson, S.D.; Kwon, Y.; Roberts, S.; Thorndike, E.H.; Coan, T.E.; Dominick, J.; Fadeyev, V.; Korolkov, I.; Lambrecht, M.; Sanghera, S.; Shelkov, V.; Skwarnicki, T.; Stroynowski, R.; Volobouev, I.; Wei, G.; Artuso, M.; Gao, M.; Goldberg, M.; He, D.; Horwitz, N.; Kopp, S.; Moneti, G.C.; Mountain, R.; Muheim, F.; Mukhin, Y.; Playfer, S.

1996-02-01

We report the observation of the Cabibbo-suppressed decays {Lambda}{sub {ital c}}{sup +}{r_arrow}{ital pK{sup {minus}}K{sup +}} and {Lambda}{sub {ital c}}{sup +}{r_arrow}{ital p}{phi} using data collected with the CLEO II detector at CESR. The latter mode, observed for the first time with significant statistics, is of interest as a test of color suppression in charm decays. We have determined the branching ratios for these modes relative to {Lambda}{sub {ital c}}{sup +}{r_arrow}{ital pK{sup {minus}}}{pi}{sup +} and compared our results with theory. {copyright} {ital 1996 The American Physical Society.}

SU(3) chiral symmetry for baryons

International Nuclear Information System (INIS)

Dmitrasinovic, V.

2011-01-01

Three-quark nucleon interpolating fields in QCD have well-defined SU L (3)xSU R (3) and U A (1) chiral transformation properties, viz. [(6,3)+(3,6)], [(3,3-bar)+(3-bar,3)], [(8,1)+(1,8)] and their 'mirror' images. It has been shown (phenomenologically) in Ref. [2] that mixing of the [(6,3)+(3,6)] chiral multiplet with one ordinary ('naive') and one 'mirror' field belonging to the [(3,3-bar)+(3-bar,3)], [(8,1)+(1,8)] multiplets can be used to fit the values of the isovector (g A (3) ) and the flavor-singlet (isoscalar) axial coupling (g A (0) ) of the nucleon and then predict the axial F and D coefficients, or vice versa, in reasonable agreement with experiment. In an attempt to derive such mixing from an effective Lagrangian, we construct all SU L (3)xSU R (3) chirally invariant non-derivative one-meson-baryon interactions and then calculate the mixing angles in terms of baryons' masses. It turns out that there are (strong) selection rules: for example, there is only one non-derivative chirally symmetric interaction between J 1/2 fields belonging to the [(6,3)+(3,6)] and the [(3,3-bar)+(3-bar,3)] chiral multiplets, that is also U A (1) symmetric. We also study the chiral interactions of the [(3,3-bar)+(3-bar,3)] and [(8,1)+(1,8)] nucleon fields. Again, there are selection rules that allow only one off-diagonal non-derivative chiral SU L (3)xSU R (3) interaction of this type, that also explicitly breaks the U A (1) symmetry. We use this interaction to calculate the corresponding mixing angles in terms of baryon masses and fit two lowest lying observed nucleon (resonance) masses, thus predicting the third (J = 1/2, I = 3/2)Δ resonance, as well as one or two flavor-singlet Λ hyperon(s), depending on the type of mixing. The effective chiral Lagrangians derived here may be applied to high density matter calculations.

Baryonic dark matter

International Nuclear Information System (INIS)

Uson, Juan M.

2000-01-01

Many searches for baryonic dark matter have been conducted but, so far, all have been unsuccessful. Indeed, no more than 1% of the dark matter can be in the form of hydrogen burning stars. It has recently been suggested that most of the baryons in the universe are still in the form of ionized gas so that it is possible that there is no baryonic dark matter. Although it is likely that a significant fraction of the dark matter in the Milky Way is in a halo of non-baryonic matter, the data do not exclude the possibility that a considerable amount, perhaps most of it, could be in a tenuous halo of diffuse ionized gas

CP violation in multibody decays of beauty baryons

Energy Technology Data Exchange (ETDEWEB)

Durieux, Gauthier

2016-08-15

Beauty baryons are being observed in large numbers in the LHCb detector. The rich kinematic distributions of their multibody decays are therefore becoming accessible and provide us with new opportunities to search for CP violation. We analyse the angular distributions of some three- and four-body decays of spin-1/2 baryons using the Jacob-Wick helicity formalism. The asymmetries that provide access to small differences of CP-odd phases between decay amplitudes of identical CP-even phases are notably discussed. The understanding gained on processes featuring specific resonant intermediate states allows us to establish which asymmetries are relevant for what purpose. It is for instance shown that some CP-odd angular asymmetries measured by the LHCb collaboration in the Λ{sub b}→Λφ→pπ K{sup +}K{sup -} decay are expected to vanish identically.

The exchange of correlated pions and kaons in the baryon-baryon interaction

International Nuclear Information System (INIS)

Reuber, A.G.

1995-09-01

The exchange of two correlated pions or kaons provides the main part of the intermediate-range attraction between two baryons. In this work, a dynamical model for correlated two-pion and two-kaon exchange in the baryon-baryon interaction is presented, both in the scalar-isoscalar (σ) and the vector-isovector (ρ) channel. The contribution of correlated ππ and K anti K exchange is derived from the amplitudes for the transition of a baryon-antibaryon state (B anti B') to a ππ or K anti K state in the pseudophysical region by applying dispersion theory and unitarity. For the B anti B'→ππ, K anti K amplitudes a microscopic model is constructed, which is based on the hadron-exchange picture. The Born terms include contributions from baryon-exchange as well as ρ-pole diagrams. The correlations between the two pseudoscalar mesons are taken into account exactly by means of ππ-K anti K amplitudes derived likewise from a meson-exchange model, which is in line with the empirical ππ data. The parameters of the B anti B'→ππ, K anti K model, which are related to each other by the assumption of SU(3) symmetry, are determined by the adjustment to the quasiempirical N anti N→ππ amplitudes in the pseudophysical region. It is found that correlated K anti K exchange being negligible in the NN interaction plays an important role in the σ-channel for baryon-baryon states with non-vanishing strangeness. The strength of correlated ππ plus K anti K exchange in the σ-channel decreases with the strangeness of the baryon-baryon system becoming more negative. Due to the admixture of baryon-exchange processes to the SU(3)-symmetric ρ-pole contributions the results for correlated ππ-exchange in the vector-isovector channel deviate from what is expected in the naive SU(3) picture for genuine ρ-exchange. (orig.)

Recent results on weak decays of charmed mesons from the Mark III experiment

International Nuclear Information System (INIS)

Browder, T.E.

1989-01-01

Recent results from the Mark III experiment on weak decays of charmed mesons are presented. Measurements of the resonant substructure of D 0 → K - π + π - π + decays, the first model independent result on D s → φπ + , as well as limits on D s → ηπ + and D s → η'π + are described. The implications of these new results are also discussed. 37 refs., 7 figs., 4 tabs

Proceedings of the tau-charm factory workshop

International Nuclear Information System (INIS)

Beers, L.V.

1989-06-01

This report contains papers on the following main topics: machine physics; tau physics; D and D s physics; J/Ψ and charmonium physics; tau charm factories; workshop summary; accelerator physics; tau physics; charmed meson physics; J/Ψ and charmonium physics; and detector

Charm production in the dual topological unitarization model

International Nuclear Information System (INIS)

Batunin, A.V.

1986-01-01

The open and hidden charm hadroproduction has been traced up to the SPS energies in the framework of the dual parton model. The free parameter (the suppression of the charmed sea) comes from the experiments on D-meson hadroproduction. Then the hidden-charm production data are described assuming that the J/ψ-meson production suggests only one cc-bar pair in the string, while the pair ψψ production suggests two cc-bar pairs

Neutron-antineutron oscillation and baryonic majoron: low scale spontaneous baryon violation

Energy Technology Data Exchange (ETDEWEB)

Berezhiani, Zurab [Universita dell' Aquila, Dipartimento delle Scienze Fisiche e Chimiche, L' Aquila (Italy); INFN, Laboratori Nazionali Gran Sasso, L' Aquila (Italy)

2016-12-15

We discuss the possibility that baryon number B is spontaneously broken at low scales, of the order of MeV or even smaller, inducing the neutron-antineutron oscillation at the experimentally accessible level. An associated Goldstone particle-baryonic majoron can have observable effects in neutron to antineutron transitions in nuclei or dense nuclear matter. By extending baryon number to an anomaly-free B - L symmetry, the baryo-majoron can be identified with the ordinary majoron associated with the spontaneous breaking of lepton number, and it can have interesting implications for neutrinoless 2β decay with the majoron emission. We also discuss the hypothesis that baryon number can be spontaneously broken by QCD itself via the six-quark condensates. (orig.)

Spectroscopy of new particles

International Nuclear Information System (INIS)

Goldhaber, G.

1977-08-01

A review of the spectroscopy of the ''psions'' with hidden charm or charm quantum number ch = o is followed by a discussion of charmed mesons and baryons. The anomalous C-μ events and the heavy lepton hypothesis are briefly considered

DO -- antiMixing and Rare Charm Decays

Energy Technology Data Exchange (ETDEWEB)

Miller, Jeanne M; Burdman, Gustavo

2003-10-06

We review the current status of flavor-changing neutral currents in the charm sector. We focus on the standard-model predictions and identify the main sources of theoretical uncertainties in both charm mixing and rare charm decays. The potential of these observables for constraining short-distance physics in the standard model and its extensions is compromised by the presence of large nonperturbative effects. We examine the possible discovery windows in which short-distance physics can be tested and study the effects of various extensions of the standard model. The current experimental situation and future prospects are reviewed.

Charm physics at BES III

International Nuclear Information System (INIS)

Wang Yifang

2011-01-01

Since the discovery of J/Ψ and the τ lepton in 70's, the study of τ-charm physics became very active: several dedicated e + e - colliders were built and tremendous progress were obtained. In this paper, the main reasoning,the content and the characteristics of the τ-charm physics study are discussed, together with the scientific motivations and the latest results of the recently completed upgrade of the Beijing Electron-Positron Collider (BEPC II) and the new Beijing Spectrometer (BES III). (authors)

Baryons and dual unitarization

International Nuclear Information System (INIS)

Konishi, K.-I.

1977-05-01

Processes involving baryons are discussed in the scheme of dual unitarization. In particular, the topological expansion is generalized to any hadronic S-matrix elements involving baryons and/or mesons. The expansion is based on a model for the baryon propagator, which is a set of three planar Feynman diagrams joined at a junction line. The resulting expansion is a double expansion in 1/N (N = the number of quark flavours) and in the number of baryon loops. Based on this, several new observations are made in phenomenological problems, and a unifying point of view in stressed. The scheme is evidently crossing invariant, and unitarity constraints are imposed order by order in 1/N and in the baryon loop number. (author)

Study of semileptonic decays of B mesons to charmed baryons

International Nuclear Information System (INIS)

Bonvicini, G.; Cinabro, D.; Greene, R.; Perera, L.P.; Zhou, G.J.; Chadha, M.; Chan, S.; Eigen, G.; Miller, J.S.; OGrady, C.; Schmidtler, M.; Urheim, J.; Weinstein, A.J.; Wuerthwein, F.; Bliss, D.W.; Masek, G.; Paar, H.P.; Prell, S.; Sharma, V.; Asner, D.M.; Gronberg, J.; Hill, T.S.; Lange, D.J.; Morrison, R.J.; Nelson, H.N.; Nelson, T.K.; Roberts, D.; Ryd, A.; Balest, R.; Behrens, B.H.; Ford, W.T.; Park, H.; Roy, J.; Smith, J.G.; Alexander, J.P.; Baker, R.; Bebek, C.; Berger, B.E.; Berkelman, K.; Bloom, K.; Boisvert, V.; Cassel, D.G.; Crowcroft, D.S.; Dickson, M.; Dombrowski, S. von; Drell, P.S.; Ecklund, K.M.; Ehrlich, R.; Foland, A.D.; Gaidarev, P.; Gibbons, L.; Gittelman, B.; Gray, S.W.; Hartill, D.L.; Heltsley, B.K.; Hopman, P.I.; Kandaswamy, J.; Kim, P.C.; Kreinick, D.L.; Lee, T.; Liu, Y.; Mistry, N.B.; Ng, C.R.; Nordberg, E.; Ogg, M.; Patterson, J.R.; Peterson, D.; Riley, D.; Soffer, A.; Valant-Spaight, B.; Ward, C.; Athanas, M.; Avery, P.; Jones, C.D.; Lohner, M.; Patton, S.; Prescott, C.; Yelton, J.; Zheng, J.; Brandenburg, G.; Briere, R.A.; Ershov, A.; Gao, Y.S.; Kim, D.Y.; Wilson, R.; Yamamoto, H.; Browder, T.E.; Li, Y.; Rodriguez, J.L.; Bergfeld, T.; Eisenstein, B.I.; Ernst, J.; Gladding, G.E.; Gollin, G.D.; Hans, R.M.; Johnson, E.; Karliner, I.; Marsh, M.A.; Palmer, M.; Selen, M.; Thaler, J.J.

1998-01-01

Using data collected by the CLEO II detector at a center-of-mass energy on or near the Υ(4S) resonance, we have determined the 90% confidence level upper limit B(bar B→Λ c + e - X)/B(bar B→(Λ c + or bar Λ c - )X) - →Λ c + bar pe - bar ν e )/B(bar B→Λ c + bar pX) c + bar pX)/B(bar B→(Λ c + or bar Λ c - )X)=0.57±0.05±0.05. copyright 1998 The American Physical Society

STUDY OF SEMILEPTONIC DECAYS OF B MESONS TO CHARMED BARYONS

International Nuclear Information System (INIS)

Jessop, Colin P.

2003-01-01

Using data collected by the CLEO II detector at a center-of-mass energy on or near the Υ(4S) resonance, we have determined the 90% confidence level upper limit Β((bar B) → Λ c + e - X)/Β((bar B) → (Λ c + or (bar Λ) c - )X) - → Λ c + (bar p)e - (bar ν) e )/Β((bar B) → Λ c + (bar p)X) c + (bar p)X)/Β((bar B) → (Λ c + or (bar Λ) c - )X) = 0.57 ± 0.05 ± 0.05

Baryonic dark matter

International Nuclear Information System (INIS)

Lynden-Bell, D.; Gilmore, G.

1990-01-01

Dark matter, first definitely found in the large clusters of galaxies, is now known to be dominant mass in the outer parts of galaxies. All the mass definitely deduced could be made up of baryons, and this would fit well with the requirements of nucleosynthesis in a big bang of small Ω B . However, if inflation is the explanation of the expansion and large scale homogeneity of the universe and of baryon synthesis, and if the universe did not have an infinite extent at the big bang, then Ω should be minutely greater than unity. It is commonly hypothesized that most mass is composed of some unknown, non-baryonic form. This book first discusses the known forms, comets, planets, brown dwarfs, stars, gas, galaxies and Lyman α clouds in which baryons are known to exist. Limits on the amount of dark matter in baryonic form are discussed in the context of the big bang. Inhomogeneities of the right type alleviate the difficulties associated with Ω B = 1 cosmological nucleosynthesis

The search for charm, beauty, and truth at high energies. Vol. 16

International Nuclear Information System (INIS)

Bellini, G.; Ting, S.C.C.

1984-01-01

This book examines present experimental knowledge on branching ratios, lifetimes, cross sections, and production mechanisms of charm and heavy flavors. The bases of the theoretical ideas and predictions, and such experimental methods as triggers, techniques, and devices are discussed. Topics covered include the search for charm and beauty with e + e - beams, the search for charm and beauty at Fermilab, the search for charm with bubble chambers, the use of visual detectors in the search for charm and other flavors, lifetime measurements, live targets for lifetime measurements, production cross sections of charm and new flavors, high resolution vertex detectors to search for charm and other flavors, the search for heavy flavors, and special triggers to search for charm and heavy flavors. The contributors participated in the Europhysics Study Conference on High-Energy Physics held in Italy in 1981

Calculation of baryon sum rules and SU(4) mass formulae for mesons and baryons

International Nuclear Information System (INIS)

Bongardt, K.

1976-01-01

Light cone coordinates and field-field anticommutators for the free quark model on the light cone are introduced and light cone charges and light cone currents for the free quark model as well as sum rules for the meson and quark states are derived. The derivation of sum rules for the baryons is attempted. It is seen that it is possible formally to derive the same sum rules for the baryons and for the quarks. The baryon sums were derived through the symmetry properties of the baryon fields. Explicit assumptions about the spatial distribution of the three quarks in the baryons were not utilized. The meson-baryon Σ-terms, Zweig's rules in the SU (4) and a number of properties of the M-matrix are discussed. (BJ) [de

Charm production in SIBYLL

CERN Document Server

Riehn, Felix; Fedynitch, Anatoli; Gaisser, Thomas K.; Stanev, Todor

2015-08-04

SIBYLL 2.1 is an event generator for hadron interactions at the highest energies. It is commonly used to analyze and interpret extensive air shower measurements. In light of the first detection of PeV neutrinos by the IceCube collaboration the inclusive fluxes of muons and neutrinos in the atmosphere have become very important. Predicting these fluxes requires understanding of the hadronic production of charmed particles since these contribute significantly to the fluxes at high energy through their prompt decay. We will present an updated version of SIBYLL that has been tuned to describe LHC data and extended to include the production of charmed hadrons.

Study of the excited 1{sup -} charm and charm-strange mesons

Energy Technology Data Exchange (ETDEWEB)

Li, Qiang; Jiang, Yue; Wang, Tianhong; Yuan, Han; Wang, Guo-Li [Harbin Institute of Technology, Harbin (China); Chang, Chao-Hsi [CCAST (World Laboratory), P.O. Box 8730, Beijing (China); Chinese Academy of Sciences, Institute of Theoretical Physics, P.O. Box 2735, Beijing (China)

2017-05-15

We give a systematical study on the recently reported excited charm and charm-strange mesons with potential 1{sup -} spin-parity, including the D{sup *}{sub s1}(2700){sup +}, D{sup *}{sub s1}(2860){sup +}, D{sup *}(2600){sup 0}, D{sup *}(2650){sup 0}, D{sup *}{sub 1}(2680){sup 0} and D{sup *}{sub 1}(2760){sup 0}. The main strong decay properties are obtained in the framework of Bethe-Salpeter (BS) methods. Our results reveal that the two 1{sup -} charm-strange mesons can be well described by the further 2{sup 3}S{sub 1}-1{sup 3}D{sub 1} mixing scheme with a mixing angle of (8.7{sup +3.9}{sub -3.2}) {sup circle}. The predicted decay ratio (B(D{sup *}K))/(B(D K)) for D{sup *}{sub s1}(2860) is 0.62{sup +0.22}{sub -0.12}. D{sup *}(2600){sup 0} can also be explained as the 2{sup 3}S{sub 1} predominant state with a mixing angle of -(7.5{sup +4.0}{sub -3.3}) {sup circle}. Considering the mass range, D{sup *}(2650){sup 0} and D{sup *}{sub 1}(2680){sup 0} are more likely to be the 2{sup 3}S{sub 1} predominant states, although the total widths under the two 2{sup 3}S{sub 1} and 1{sup 3}D{sub 1} assignments have no great conflict with the current experimental data. The calculated width for the LHCb D{sup *}{sub 1}(2760){sup 0} seems to be about 100 MeV larger than the experimental measurement if taking it as 1{sup 3}D{sub 1} or 1{sup 3}D{sub 1} dominant state c anti u. The comparisons with other calculations and several important decay ratios are also presented. For the identification of these 1{sup -} charm mesons, further experimental information, such as (B(Dπ))/(B(D{sup *}π)), is necessary. (orig.)

Helicity amplitudes and electromagnetic decays of hyperon resonances

International Nuclear Information System (INIS)

Cauteren, T. van; Ryckebusch, J.; Metsch, B.; Petry, H.R.

2005-01-01

We present results for the helicity amplitudes of the lowest-lying hyperon resonances Y * , computed within the framework of the Bonn Constituent-Quark model, which is based on the Bethe-Salpeter approach. The seven parameters entering the model were fitted to the best-known baryon masses. Accordingly, the results for the helicity amplitudes are genuine predictions. Some hyperon resonances are seen to couple more strongly to a virtual photon with finite Q 2 than to a real photon. Other Y * 's, such as the S 01 (1670) Λ-resonance or the S 11 (1620) Σ-resonance, couple very strongly to real photons. We present a qualitative argument for predicting the behaviour of the helicity asymmetries of baryon resonances at high Q 2 . (orig.)

Observation of the Heavy Baryons Sigma b and Sigma b*.

Science.gov (United States)

Aaltonen, T; Abulencia, A; Adelman, J; Affolder, T; Akimoto, T; Albrow, M G; Amerio, S; Amidei, D; Anastassov, A; Anikeev, K; Annovi, A; Antos, J; Aoki, M; Apollinari, G; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Azzi-Bacchetta, P; Azzurri, P; Bacchetta, N; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Baroiant, S; Bartsch, V; Bauer, G; Beauchemin, P-H; Bedeschi, F; Behari, S; Bellettini, G; Bellinger, J; Belloni, A; Benjamin, D; Beretvas, A; Beringer, J; Berry, T; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bolshov, A; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrera, S; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carillo, S; Carlsmith, D; Carosi, R; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, I; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Cilijak, M; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Coca, M; Compostella, G; Convery, M E; Conway, J; Cooper, B; Copic, K; Cordelli, M; Cortiana, G; Crescioli, F; Cuenca Almenar, C; Cuevas, J; Culbertson, R; Cully, J C; DaRonco, S; Datta, M; D'Auria, S; Davies, T; Dagenhart, D; de Barbaro, P; De Cecco, S; Deisher, A; De Lentdecker, G; De Lorenzo, G; Dell'Orso, M; Delli Paoli, F; Demortier, L; Deng, J; Deninno, M; De Pedis, D; Derwent, P F; Di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Dörr, C; Donati, S; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, I; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Field, R; Flanagan, G; Forrest, R; Forrester, S; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garcia, J E; Garberson, F; Garfinkel, A F; Gay, C; Gerberich, H; Gerdes, D; Giagu, S; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Goldstein, J; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Hamilton, A; Han, B-Y; Han, J Y; Handler, R; Happacher, F; Hara, K; Hare, D; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hauser, J; Hays, C; Heck, M; Heijboer, A; Heinemann, B; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Holloway, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; Iyutin, B; James, E; Jang, D; Jayatilaka, B; Jeans, D; Jeon, E J; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Karchin, P E; Kato, Y; Kemp, Y; Kephart, R; Kerzel, U; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Klute, M; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kraan, A C; Kraus, J; Kreps, M; Kroll, J; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhlmann, S E; Kuhr, T; Kulkarni, N P; Kusakabe, Y; Kwang, S; Laasanen, A T; Lai, S; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, J; Lee, J; Lee, Y J; Lee, S W; Lefèvre, R; Leonardo, N; Leone, S; Levy, S; Lewis, J D; Lin, C; Lin, C S; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Lu, R-S; Lucchesi, D; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; Lytken, E; Mack, P; MacQueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manousakis, A; Margaroli, F; Marginean, R; Marino, C; Marino, C P; Martin, A; Martin, M; Martin, V; Martínez, M; Martínez-Ballarín, R; Maruyama, T; Mastrandrea, P; Masubuchi, T; Matsunaga, H; Mattson, M E; Mazini, R; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzemer, S; Menzione, A; Merkel, P; Mesropian, C; Messina, A; Miao, T; Miladinovic, N; Miles, J; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyamoto, A; Moed, S; Moggi, N; Mohr, B; Moon, C S; Moore, R; Morello, M; Movilla Fernandez, P; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagano, A; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Necula, V; Neu, C; Neubauer, M S; Nielsen, J; Nodulman, L; Norniella, O; Nurse, E; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Oldeman, R; Orava, R; Osterberg, K; Pagliarone, C; Palencia, E; Papadimitriou, V; Papaikonomou, A; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Piedra, J; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Portell, X; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohos, F; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Reisert, B; Rekovic, V; Renton, P; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Roy, P; Ruiz, A; Russ, J; Rusu, V; Saarikko, H; Safonov, A; Sakumoto, W K; Salamanna, G; Saltó, O; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savard, P; Savoy-Navarro, A; Scheidle, T; Schlabach, P; Schmidt, E E; Schmidt, M A; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scott, A L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sfyrla, A; Shalhout, S Z; Shapiro, M D; Shears, T; Shepard, P F; Sherman, D; Shimojima, M; Shochet, M; Shon, Y; Shreyber, I; Sidoti, A; Sinervo, P; Sisakyan, A; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Soderberg, M; Soha, A; Somalwar, S; Sorin, V; Spalding, J; Spinella, F; Spreitzer, T; Squillacioti, P; Stanitzki, M; Staveris-Polykalas, A; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Stuart, D; Suh, J S; Sukhanov, A; Sun, H; Suslov, I; Suzuki, T; Taffard, A; Takashima, R; Takeuchi, Y; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Tesarek, R J; Thom, J; Thompson, A S; Thomson, E; Tipton, P; Tiwari, V; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Tourneur, S; Trischuk, W; Tsuno, S; Tu, Y; Turini, N; Ukegawa, F; Uozumi, S; Vallecorsa, S; van Remortel, N; Varganov, A; Vataga, E; Vazquez, F; Velev, G; Vellidis, C; Veramendi, G; Veszpremi, V; Vidal, M; Vidal, R; Vila, I; Vilar, R; Vine, T; Vogel, M; Vollrath, I; Volobouev, I; Volpi, G; Würthwein, F; Wagner, P; Wagner, R G; Wagner, R L; Wagner, J; Wagner, W; Wallny, R; Wang, S M; Warburton, A; Waters, D; Weinberger, M; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Wynne, S M; Yagil, A; Yamamoto, K; Yamaoka, J; Yamashita, T; Yang, C; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zaw, I; Zhang, X; Zhou, J; Zucchelli, S

2007-11-16

We report an observation of new bottom baryons produced in pp collisions at the Tevatron. Using 1.1 fb(-1) of data collected by the CDF II detector, we observe four Lambda b 0 pi+/- resonances in the fully reconstructed decay mode Lambda b 0-->Lambda c + pi-, where Lambda c+-->pK* pi+. We interpret these states as the Sigma b(*)+/- baryons and measure the following masses: m Sigma b+=5807.8 -2.2 +2.0(stat.)+/-1.7(syst.) MeV/c2, m Sigma b- =5815.2+/-1.0(stat.)+/-1.7(syst.) MeV/c2, and m(Sigma b*)-m(Sigma b)=21.2-1.9 +2.0(stat.)-0.3+0.4(syst.) MeV/c2.

Searching for hidden-charm baryonium signals in QCD sum rules

Energy Technology Data Exchange (ETDEWEB)

Chen, Hua-Xing; Zhou, Dan [Beihang University, School of Physics, Beijing Key Laboratory of Advanced Nuclear Materials and Physics, Beijing (China); Chen, Wei [University of Saskatchewan, Department of Physics and Engineering Physics, Saskatoon, SK (Canada); Liu, Xiang [Lanzhou University, School of Physical Science and Technology, Lanzhou (China); Lanzhou University, Research Center for Hadron and CSR Physics, Institute of Modern Physics of CAS, Lanzhou (China); Zhu, Shi-Lin [Peking University, School of Physics, State Key Laboratory of Nuclear Physics and Technology, Beijing (China); Collaborative Innovation Center of Quantum Matter, Beijing (China); Peking University, Center of High Energy Physics, Beijing (China)

2016-11-15

We give an explicit QCD sum rule investigation for hidden-charm baryonium states with the quark content u anti ud anti dc anti c, spin J = 0/1/2/3, and of both positive and negative parities. We systematically construct the relevant local hidden-charm baryonium interpolating currents, which can actually couple to various structures, including hidden-charm baryonium states, charmonium states plus two pions, and hidden-charm tetraquark states plus one pion, etc. We do not know which structure these currents couple to at the beginning, but after sum rule analyses we can obtain some information. We find some of them can couple to hidden-charm baryonium states, using which we evaluate the masses of the lowest-lying hidden-charm baryonium states with quantum numbers J{sup P} = 2{sup -}/3{sup -}/0{sup +}/1{sup +}/2{sup +} to be around 5.0 GeV. We suggest to search for hidden-charm baryonium states, especially the one of J = 3{sup -}, in the D-wave J/ψππ and P-wave J/ψρ and J/ψω channels in this energy region. (orig.)

Flavor mixing and charm decay

International Nuclear Information System (INIS)

Chau Wang, L.C.

1980-01-01

The results of mixing matrix determination and their implications on heavy quark decays are given. The decays of charm mesons D 0 , D + , F + into two pseudoscalar mesons are discussed in the framework of SU(3) symmetry. The charm decays are also discussed in terms of quark diagrams. It is demonstrated that the differences observed in the lifetimes of D 0 and D + , and in the branching ratios B(D 0 → K - K + ) and B(D 0 → π - π + ) can be easily incorporated. 3 figures

Hadroproduction characteristics of charm and beauty

International Nuclear Information System (INIS)

Reucroft, S.

1987-01-01

In this article the authors review the present status of their knowledge on the hadroproduction characteristics of charm and beauty. During a brief description of the properties of all charm and beauty particles reportedly observed in hadron-hadron experiments they discuss the strengths and weaknesses of the various experimental techniques. In particular they emphasise the quantitative problems associated with nuclear target experiments and show the progress that is being made in understanding the A-dependence problem. Focussing on charm cross sections the authors see that the data are becoming sufficiently good to give us a reliable and coherent picture which provides a serious test of the QCD fusion model. This same fusion model is then used with existing beauty cross section determinations to make some extrapolations. Finally, a few remaining puzzles and curiosities are underlined

Baryonic Dark Matter

OpenAIRE

Silk, Joseph

1994-01-01

In the first two of these lectures, I present the evidence for baryonic dark matter and describe possible forms that it may take. The final lecture discusses formation of baryonic dark matter, and sets the cosmological context.

Strange and heavy hadrons production from coalescence plus fragmentation in AA collisions at RHIC and LHC

Science.gov (United States)

Plumari, Salvatore; Minissale, Vincenzo; Das, Santosh K.; Scardina, Francesco; Greco, Vincenzo

2018-02-01

In a coalescence plus fragmentation approach we study the pT spectra of charmed hadrons D0, Ds up to about 10 GeV and the Λ+c /D0 ratio from RHIC to LHC energies. In this study we have included the contribution from decays of heavy hadron resonances and also that due to fragmentation of heavy quarks that are left in the system after coalescence. The pT dependence of the heavy baryon/meson ratios is found to be sensitive to the heavy quark mass. In particular we found that the Λc/D0 is much flatter than the one for light baryon/meson ratio like p/π and Λ/K.

Nuclear Filtering of Intrinsic Charm

International Nuclear Information System (INIS)

Kopeliovich, B. Z.; Potashnikova, I. K.; Schmidt, Ivan

2010-01-01

Nuclei are transparent for a heavy intrinsic charm (IC) component of the beam hadrons, what leads to an enhanced nuclear dependence of open charm production at large Feynman x F . Indeed, such an effect is supported by data from the SELEX experiment published recently [1]. Our calculations reproduce well the data, providing strong support for the presence of IC in hadrons in amount less than 1%. Moreover, we performed an analysis of nuclear effects in J/Ψ production and found at large x F a similar, albeit weaker effect, which does not contradict data.

Measurement of charm fragmentation fractions in photoproduction 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, Muinch (Germany); Adamczyk, L. [AGH-Univ. of Science and Technology, Krakow (Poland). Faculty of Physics and Applied Computer Science] [and others; Collaboration: ZEUS Collaboration

2013-06-15

The production of D{sup 0}, D{sup *+}, D{sup +}, D{sub s}{sup +} and {Lambda}{sub c}{sup +} charm hadrons and their antiparticles in ep scattering at HERA has been studied with the ZEUS detector, using a total integrated luminosity of 372 pb{sup -1}. The fractions of charm quarks hadronising into a particular charm hadron were derived. In addition, the ratio of neutral to charged D-meson production rates, the fraction of charged D mesons produced in a vector state, and the strangeness-suppression factor have been determined. The measurements have been performed in the photoproduction regime. The charm hadrons were reconstructed in the range of transverse momentum p{sub T} > 3.8GeV and pseudorapidity vertical stroke {eta} vertical stroke <1.6. The charm fragmentation fractions are compared to previous results from HERA and from e{sup +}e{sup -} experiments. The data support the hypothesis that fragmentation is independent of the production process.

Baryon Chiral Dynamics

Energy Technology Data Exchange (ETDEWEB)

Becher,

2002-08-08

After contrasting the low energy effective theory for the baryon sector with one for the Goldstone sector, I use the example of pion nucleon scattering to discuss some of the progress and open issues in baryon chiral perturbation theory.

Power corrections from decoupling of the charm quark

Science.gov (United States)

Knechtli, Francesco; Korzec, Tomasz; Leder, Björn; Moir, Graham; Alpha Collaboration

2017-11-01

Decoupling of heavy quarks at low energies can be described by means of an effective theory as shown by S. Weinberg in Ref. [1]. We study the decoupling of the charm quark by lattice simulations. We simulate a model, QCD with two degenerate charm quarks. In this case the leading order term in the effective theory is a pure gauge theory. The higher order terms are proportional to inverse powers of the charm quark mass M starting at M-2. Ratios of hadronic scales are equal to their value in the pure gauge theory up to power corrections. We show, by precise measurements of ratios of scales defined from the Wilson flow, that these corrections are very small and that they can be described by a term proportional to M-2 down to masses in the region of the charm quark mass.

Exotic baryon pπ+π+ states observation in the π+p → pπ+π+π- reaction

International Nuclear Information System (INIS)

Mikhajlichenko, V.I.; Drutskoj, A.G.; Morgunov, V.L.; Nikitin, S.Ya.; Kiselevich, I.L.; Shidlovskij, A.V.

1987-01-01

Production of exotic baryon states in the π + p→pπ + π + π s - - reaction, the π + meson momentum being 4.23 GeV/c, was observed (where π s - -π - -meson with p * <0). Masses and widths of resonances observed in baryon exchange reactions are 1387±15(8±10), 1581±15(73±15), 1759±13(76±12) and 2074±19(147±41), respectively

Including the Δ(1232) resonance in baryon chiral perturbation theory

International Nuclear Information System (INIS)

Hacker, C.; Wies, N.; Scherer, S.; Gegelia, J.

2005-01-01

Baryon chiral perturbation theory with explicit Δ(1232) degrees of freedom is considered. The most general interactions of pions, nucleons, and Δ consistent with all underlying symmetries as well as with the constraint structure of higher-spin fields are constructed. By use of the extended on-mass-shell renormalization scheme, a manifestly Lorentz-invariant effective-field theory with a systematic power counting is obtained. As applications, we discuss the mass of the nucleon, the pion-nucleon σ term, and the pole of the Δ propagator

D{sub s1}{sup *}(2860) and D{sub s3}{sup *}(2860): candidates for 1D charmed-strange mesons

Energy Technology Data Exchange (ETDEWEB)

Song, Qin-Tao [Chinese Academy of Sciences, Nuclear Theory Group, Institute of Modern Physics, Lanzhou (China); Lanzhou University and Institute of Modern Physics of CAS, Research Center for Hadron and CSR Physics, Lanzhou (China); University of Chinese Academy of Sciences, Beijing (China); Chen, Dian-Yong [Chinese Academy of Sciences, Nuclear Theory Group, Institute of Modern Physics, Lanzhou (China); Lanzhou University and Institute of Modern Physics of CAS, Research Center for Hadron and CSR Physics, Lanzhou (China); Liu, Xiang [Lanzhou University and Institute of Modern Physics of CAS, Research Center for Hadron and CSR Physics, Lanzhou (China); Lanzhou University, School of Physical Science and Technology, Lanzhou (China); Matsuki, Takayuki [Tokyo Kasei University, Tokyo (Japan); RIKEN, Theoretical Research Division, Nishina Center, Saitama (Japan)

2015-01-01

Newly observed two charmed-strange resonances, D{sub s1}{sup *}(2860) and D{sub s3}{sup *}(2860), are investigated by calculating their Okubo-Zweig-Iizuka-allowed strong decays, which shows that they are suitable candidates for the 1{sup 3}D{sub 1} and 1{sup 3}D{sub 3} states in the charmed-strange meson family. Our study also predicts other main decay modes of D{sub s1}{sup *}(2860) and D{sub s3}{sup *}(2860), which can be accessible at the future experiment. In addition, the decay behaviors of the spin partners of D{sub s1}{sup *}(2860) and D{sub s3}{sup *}(2860), i.e., 1D(2{sup -}) and 1D'(2{sup -}), are predicted in this work, which are still missing at present. The experimental search for the missing 1D(2{sup -}) and 1D'(2{sup -}) charmed-strange mesons is an intriguing and challenging task for further experiments. (orig.)

Measuring baryon-(anti-)baryon interaction cross-sections with femtoscopy in Heavy-Ion Collisions

Energy Technology Data Exchange (ETDEWEB)

Kisiel, A.

2016-12-15

Two-particle correlations at low relative momentum (femtoscopy) are used to study the space-time dynamics of the source created in heavy-ion collisions. The same method can be used in a novel way to study the Final State Interaction potential for various particle pairs. The parameters are also directly related to the relevant interaction cross-sections. Of special interest are correlations of baryons, where the strong interaction often dominates. The femtoscopic technique offers a unique opportunity to study this interaction in such systems. In this work we discuss the similarities and differences of such measurement for baryon-baryon and baryon-antibaryon pairs.

New preliminary results on the physics of charm hadroproduction subprocesses

International Nuclear Information System (INIS)

Appel, J.A.

1994-10-01

This paper reviews the results and physics of two contributed papers to ICHEP94. Both papers relate to charm meson hadroproduction at Fermilab fixed target energies. The first (from E769) addresses the total forward cross section for charm mesons (D ± and D s ± ) produced by π ± , K ± , and proton beams. The second paper (from E791) deals with the asymmetries in the differential cross sections for charged D mesons produced in the forward direction by π - beam. The physics most directly related to the results of the E769 paper are the gluon distributions in the incident hadrons as well as perturbative QCD calculations of charm quark production and the charm quark mass. The E791 results address the details of the hadronization process after production of the charm quarks

Measurement of the inclusive charmless and double-charm B branching ratios

CERN Document Server

Abreu, P; Adye, T; Adzic, P; 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; Barbier, R; Bardin, Dimitri Yuri; Barker, G; Baroncelli, A; Bärring, O; Bates, M J; Battaglia, Marco; Baubillier, M; Becks, K H; Begalli, M; Beillière, P; Belokopytov, Yu A; Belous, K S; 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; Bonesini, M; Bonivento, W; Boonekamp, M; Booth, P S L; Borgland, A W; Borisov, G; Bosio, C; Botner, O; Boudinov, E; Bouquet, B; Bourdarios, C; Bowcock, T J V; Bozovic, I; Bozzo, M; Branchini, P; Brand, K D; Brenke, T; Brenner, R A; Brown, R; 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; Carena, F; Carroll, L; Caso, Carlo; Castillo-Gimenez, M V; Cattai, A; Cavallo, F R; Cerruti, C; 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; Collins, P; Colomer, M; Contri, R; Cortina, E; Cosme, G; Cossutti, F; Cowell, J H; Crawley, H B; Crennell, D J; Crosetti, G; Cuevas-Maestro, J; Czellar, S; D'Almagne, B; 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; Duperrin, A; Durand, J D; Edsall, D M; Ehret, R; Eigen, G; Ekelöf, T J C; Ekspong, Gösta; Ellert, M; Elsing, M; Engel, J P; Erzen, B; Espirito-Santo, M C; Falk, E; Fanourakis, G K; Fassouliotis, D; Fayot, J; Feindt, Michael; Fenyuk, A; Ferrari, P; Ferrer, A; Fichet, S; Firestone, A; Fischer, P A; Flagmeyer, U; 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; Gaspar, M; Gasparini, U; Gavillet, P; Gazis, E N; Gelé, D; Gerber, J P; Gerdyukov, L N; Ghodbane, N; Glege, F; Gokieli, R; Golob, B; González-Caballero, I; Gopal, Gian P; Gorn, L; Górski, M; Gracco, Valerio; Grahl, J; Graziani, E; Green, C; Grefrath, A; Gris, P; Grosdidier, G; Grzelak, K; Günther, M; Guy, J; Hahn, F; Hahn, S; Haider, S; Hajduk, Z; Hallgren, A; Hamacher, K; Harris, F J; Hedberg, V; Heising, S; 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, C; Juillot, P; 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; Krumshtein, Z; Kubinec, P; Kucewicz, W; Kurvinen, K L; Lacasta, C; 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; Lethuillier, M; Libby, J; Liko, D; Lipniacka, A; Lippi, I; Lörstad, B; Loken, J G; Lopes, J H; López, J M; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J N; Mahon, J R; Maio, A; Malek, 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; Matorras, F; Matteuzzi, C; Matthiae, Giorgio; Mazzucato, F; Mazzucato, M; McCubbin, M L; McKay, R; McNulty, R; McPherson, G; Medbo, J; Meroni, C; Meyer, W T; Michelotto, M; Migliore, E; Mirabito, L; Mitaroff, Winfried A; Mjörnmark, U; Moa, T; Møller, R; Mönig, K; Monge, M R; Moreau, X; Morettini, P; 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; Neufeld, N; 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; Paiano, S; Pain, R; Paiva, 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; Piotto, E; 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; Rames, J; Ratoff, P N; Read, A L; 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; Rosenberg, E I; Rosinsky, P; Roudeau, Patrick; Rovelli, T; Ruhlmann-Kleider, V; Ruiz, A; Saarikko, H; Sacquin, Yu; Sadovskii, A; Sajot, G; Salt, J; Sampsonidis, D; Sannino, M; Schneider, H; Schwickerath, U; Schyns, M A E; Scuri, F; Seager, P; Sedykh, Yu; Segar, A M; Sekulin, R L; Shellard, R C; Sheridan, A; Silvestre, R; Simonetto, F; Sissakian, A N; Skaali, T B; Smadja, G; Smirnov, N; Smirnova, O G; Smith, G R; Solovyanov, O; Sopczak, André; 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; Chikilev, O G; Tegenfeldt, F; Terranova, F; Thomas, J; Tilquin, A; Timmermans, J; Tkatchev, L G; Todorov, T; Todorova, S; Toet, D Z; Tomaradze, A G; Tomé, B; 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; Van Vulpen, I B; Vassilopoulos, N; Vegni, G; Ventura, L; Venus, W A; Verbeure, F; Verlato, M; Vertogradov, L S; Verzi, V; Vilanova, D; Vincent, P; Vitale, L; Vlasov, E; Vodopyanov, A S; Vrba, V; Wahlen, H; Walck, C; Waldner, F; Weiser, C; Wetherell, Alan M; Wicke, D; Wickens, J H; Wilkinson, G R; Williams, W S C; Winter, M; Witek, M; Wlodek, T; Wolf, G; Yi, J; Yushchenko, O P; Zaitsev, A; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zevgolatakos, E; Zimin, N I; Zucchelli, G C; Zumerle, G

1998-01-01

The DELPHI experiment at LEP has measured the inclusive charmless $B$ hadron decay branching ratio, the $B$ branching ratio into two charmed particles, and the total number of charmed particles per $B$ decay, using the hadronic Z data taken between 1992 and 1995. The results are extracted from a fit to the $b$-tagging probability distribution based on the precise impact parameter measurements made using the microvertex detector. The inclusive charmless $B$ branching ratio, including $B$ decays into hidden charm ($c\\bar{c}$), is measured to be $0.033 \\pm 0.021$. The $B$ branching ratio into two open charmed particles is $0.136 \\pm 0.042$. The mean number of charmed particles per $B$ decay (including hidden charm) is $1.147 \\pm 0.041$. After subtracting the $B$ decay branching ratio into hidden charm, the charmless $B$ branching ratio is found to be $0.007 \\pm 0.021$, compatible with the Standard Model expectation. Models that predict an additional contribution to the charmless $B$ branching ratio of 0.037 or h...

E691 Dalitz plot analysis of Λc+ → pK-π+ decays

International Nuclear Information System (INIS)

Cremaldi, L.

1992-01-01

The resonant decays of the Λ c + can give insight into the weak decay mechanism of this charmed baryon. We have performed a Dalitz plot analysis of the final state for a clean sample Λ c + → pK - π + decays observed in photoproduction experiment E691 at Fermilab. We measure Γ(pK*(892)degrees)/Γ (pK - π + ) = .35 ± .09 ± .07. We also observe an unexpected enhancement at low pK- invariant mass

S-matrix analysis of the baryon electric charge correlation

Science.gov (United States)

Lo, Pok Man; Friman, Bengt; Redlich, Krzysztof; Sasaki, Chihiro

2018-03-01

We compute the correlation of the net baryon number with the electric charge (χBQ) for an interacting hadron gas using the S-matrix formulation of statistical mechanics. The observable χBQ is particularly sensitive to the details of the pion-nucleon interaction, which are consistently incorporated in the current scheme via the empirical scattering phase shifts. Comparing to the recent lattice QCD studies in the (2 + 1)-flavor system, we find that the natural implementation of interactions and the proper treatment of resonances in the S-matrix approach lead to an improved description of the lattice data over that obtained in the hadron resonance gas model.

Observation of a visible charmed particle decay in neutrino interactions

International Nuclear Information System (INIS)

Cnops, A.M.; Connolly, P.L.; Kahn, S.A.

1979-01-01

In a sample of 250 semileptonic charmed particle decays (ν/sub μ/ + Neon → μ - + e + + ... events), one clear event is found where the e + does not come directly from the ν interaction vertex but from a decay point 1.1 cm downstream of the vertex. This event is interpreted as a visible charmed particle decay: into an e + and a positive and a negative charged track. The observation of a visible charm decay in the sample is consistent with what is expected if the charm lifetime were of the order 5 x 10 -13 sec. 5 references

Excitation of the Roper resonance and study of higher baryon resonances

International Nuclear Information System (INIS)

Morsch, H.P.; Forschungszentrum Juelich GmbH

1992-01-01

The region of the P 11 resonance N(1440) is investigated in inelastic α-scattering on hydrogen using alpha-particles from Saturne with a beam momentum of 7 GeV/c. In the missing mass spectra of the scattered α-particles two effects are observed, excitation of the projectile, preferentially excited to the Δ-resonance, and excitation of the Roper resonance. The large differential cross sections indicate a structure of a compression mode. From this the compressibility of the nucleon K N may be extracted. The Roper resonance excitation corresponds to a surface mode which may be related to an oscillation of the meson cloud. The other monopole mode which corresponds to a vibration of the valence quarks should lie at about 800 MeV of excitation or above. This is the region of the P 11 (1710 MeV) resonance. Therefore experiments are important to measure the monopole strength in this energy region. Another interesting aspect is the scalar polarizability which can be extracted from inelastic dipole excitations (squeezing modes) as excitation energies above 500 MeV

Baryon bags in strong coupling QCD

Science.gov (United States)

Gattringer, Christof

2018-04-01

We discuss lattice QCD with one flavor of staggered fermions and show that in the path integral the baryon contributions can be fully separated from quark and diquark contributions. The baryonic degrees of freedom (d.o.f.) are independent of the gauge field, and the corresponding free fermion action describes the baryons through the joint propagation of three quarks. The nonbaryonic dynamics is described by quark and diquark terms that couple to the gauge field. When evaluating the quark and diquark contributions in the strong coupling limit, the partition function completely factorizes into baryon bags and a complementary domain. Baryon bags are regions in space-time where the dynamics is described by a single free fermion made out of three quarks propagating coherently as a baryon. Outside the baryon bags, the relevant d.o.f. are monomers and dimers for quarks and diquarks. The partition sum is a sum over all baryon bag configurations, and for each bag, a free fermion determinant appears as a weight factor.

Charm, Beauty and Top at HERA

International Nuclear Information System (INIS)

Behnke, O.; Geiser, A.; Lisovyi, M.

2015-06-01

Results on open charm and beauty production and on the search for top production in high-energy electron-proton collisions at HERA are reviewed. This includes a discussion of relevant theoretical aspects, a summary of the available measurements and measurement techniques, and their impact on improved understanding of QCD and its parameters, such as parton density functions and charm- and beauty-quark masses. The impact of these results on measurements at the LHC and elsewhere is also addressed.

Calm Multi-Baryon Operators

Directory of Open Access Journals (Sweden)

Berkowitz Evan

2018-01-01

Full Text Available There are many outstanding problems in nuclear physics which require input and guidance from lattice QCD calculations of few baryons systems. However, these calculations suffer from an exponentially bad signal-to-noise problem which has prevented a controlled extrapolation to the physical point. The variational method has been applied very successfully to two-meson systems, allowing for the extraction of the two-meson states very early in Euclidean time through the use of improved single hadron operators. The sheer numerical cost of using the same techniques in two-baryon systems has so far been prohibitive. We present an alternate strategy which offers some of the same advantages as the variational method while being significantly less numerically expensive. We first use the Matrix Prony method to form an optimal linear combination of single baryon interpolating fields generated from the same source and different sink interpolating fields. Very early in Euclidean time this optimal linear combination is numerically free of excited state contamination, so we coin it a calm baryon. This calm baryon operator is then used in the construction of the two-baryon correlation functions.To test this method, we perform calculations on the WM/JLab iso-clover gauge configurations at the SU(3 flavor symmetric point with mπ~ 800 MeV — the same configurations we have previously used for the calculation of two-nucleon correlation functions. We observe the calm baryon significantly removes the excited state contamination from the two-nucleon correlation function to as early a time as the single-nucleon is improved, provided non-local (displaced nucleon sources are used. For the local two-nucleon correlation function (where both nucleons are created from the same space-time location there is still improvement, but there is significant excited state contamination in the region the single calm baryon displays no excited state contamination.

Opportunities for high-sensitivity charm physics at Fermilab

International Nuclear Information System (INIS)

Kaplan, D.M.; Burnstein, R.A.; Lederman, L.M.; Rubin, H.A.; Brown, C.N.; Christian, D.C.; Gelfand, N.M.; Kwan, S.W.; Chen, T.Y.; He, M.; Koetke, D.D.; Napier, A.; Papavassiliou, V.; Yu, X.Q.

1996-07-01

The CO initiative under consideration at Fermilab makes feasible a charm experiment reconstructing >10 9 charm decays, four orders - of magnitude beyond the largest extant sample. The experiment might commence data-taking as early as 1999. In addition to programmatic charm physics such as spectroscopy, lifetimes, and QCD tests, it will have significant new-physics reach in the areas of CP violation, flavor-changing neutral-current and lepton-number-violating decays, and D o bar D bar o mixing, and should observe direct CP violation in Cabibbo-suppressed D decays if it occurs at the level predicted by the Standard Model

Can four-quark states be easily detected in baryon-antibaryon scattering?

International Nuclear Information System (INIS)

Roberts, W.; Silvestre-Brac, B.; Gignoux, C.

1990-01-01

We attempt to explain the experimental sparsity of diquonia candidates given the theoretical abundance of such states. We do this by investigating the lowest-order contributions of such states as intermediates in p bar p scattering into exclusive baryon-antibaryon final states. We find that the contributions depend on the partial widths for the meson-meson decays of the diquonia, and that resonant effects can be easily made to disappear. We conclude that if the meson-meson widths of diquonia are larger than about 50 MeV, most of these states will be extremely difficult to observe in p bar p scattering, for instance. We note that diquonia may offer a convenient means of describing some aspects of the dynamics of baryon-antibaryon scattering

Addendum to ''Radiative corrections to the Dalitz plot of semileptonic decays of neutral baryons with light or charm quarks''

International Nuclear Information System (INIS)

Martinez, A.; Tun, D.M.; Garcia, A.; Sanchez-Colon, G.

1994-01-01

We show that the radiative corrections containing terms up to order αq/πM 1 for unpolarized semileptonic decays of baryons with positron emission can be obtained by simply reversing the sign of the axial-vector form factors in the corresponding final expressions of such decays with electron emission. This rule is valid regardless of the final kinematical variables chosen and of the particular Lorentz frame in which the final results are required

Measurement of charm and beauty production in deep inelastic scattering at HERA

Energy Technology Data Exchange (ETDEWEB)

Roloff, Philipp

2011-12-15

In this thesis two measurements of heavy quark production in deep inelastic scattering at HERA are presented. Cross sections for the production of heavy quarks can be calculated in quantum chromodynamics (QCD). The heavy quark masses represent hard scales, which allow to apply perturbative methods. Charm production has been measured with the ZEUS detector using an integrated luminosity of 120 pb{sup -1}. The hadronic decay channels D{sup +} {yields} K{sup 0}{sub S}{pi}{sup +}, {lambda}{sup +}{sub c} {yields} pK{sup 0}{sub S} and {lambda}{sup +}{sub c} {yields} {lambda}{pi}{sup +} were reconstructed. The presence of a neutral strange hadron in the final state reduces the combinatorial background and extends the measured sensitivity into the region p{sub T}(D{sup +}, {lambda}{sup +}{sub c}) < 1.5 GeV. The inclusive cross section and differential cross sections in p{sub T}{sup 2} (D{sup +}), {eta}(D{sup +}), Q{sup 2} and x for the production of D{sup +} mesons are in reasonable agreement with predictions from perturbative QCD. The fraction of c quarks hadronising into {lambda}{sup +}{sub c} baryons was extracted from a combination of both investigated {lambda}{sup +}{sub c} decay channels. The result is consistent with a previous measurement in the photoproduction regime and with the average e{sup +}e{sup -} value. The production of charm and beauty quarks has been measured with the ZEUS detector using the data collected between 2004 and 2007. This data sample corresponds to an integrated luminosity of 354 pb{sup -1}. The charm and beauty contents in events with a jet were determined using the decay-length significance and invariant mass of the reconstructed secondary decay vertices. Differential cross sections in E{sup jet}{sub T}, {eta}{sup jet}, Q{sup 2} and x are in reasonable agreement with predictions for perturbative QCD. The open charm and beauty contributions to the inclusive proton structure function F{sub 2} were extracted from double differential cross

Modified skyrmion in a baryonic matter

International Nuclear Information System (INIS)

Mishustin, I.N.

1990-01-01

A unified field model describing individual baryons and baryonic matter is developed. The model is based on a chiral-symmetry Lagrangian including the scalar, pion and vector fields interacting with the scalar density and the 4-current of baryons (linear σ-model supplemented by a vector field). Essentially inhomogeneous soliton solutions of the topological type (skirmions) correspond to the individual baryons, whereas homogeneous field configurations correspond to baryonic matter. Estimations show that the model predicts a correct scale of changes of the effective mass (15%) and the radius for the baryon for a normal nuclear matter density. For high baryon densities the model with a massive vector field predicts a phase transition which results in the restoration of chiral symmetry. The new state of the system is characterized by a homogeneous distribution of the meson fields and energy

The CLAS Excited Baryon Program at Jefferson Laboratory

International Nuclear Information System (INIS)

Crede, Volker

2009-01-01

Nucleons are complex systems of confined quarks and exhibit characteristic spectra of excited states. Highly excited nucleon states are sensitive to details of quark confinement which is poorly understood within Quantum Chromodynamics (QCD), the fundamental theory of strong interactions. Thus, measurements of excited states and the corresponding determination of their properties are needed to come to a better understanding of how confinement works in nucleons. However, the excited states of the nucleon cannot simply be inferred from cleanly separated spectral lines. Quite the contrary, a spectral analysis in nucleon resonance physics is challenging because of the fact that the resonances are broadly overlapping states which decay into a multitude of final states involving mesons and baryons. To provide a consistent and complete picture of an individual nucleon resonance, the various possible production and decay channels must be treated in a multi-channel framework that permits separat

Strangeness S = -2 baryon-baryon interactions using chiral effective field theory

NARCIS (Netherlands)

Polinder, H.; Haidenbauer, J.; Meissner, U.G.

2007-01-01

We derive the leading order strangeness S =−2 baryon–baryon interactions in chiral effective field theory. The potential consists of contact terms without derivatives and of one-pseudoscalar-meson exchanges. The contact terms and the couplings of the pseudoscalar mesons to the baryons are related

New preliminary results on the physics of charm hadroproduction subprocesses

Energy Technology Data Exchange (ETDEWEB)

Appel, J.A

1994-10-01

This paper reviews the results and physics of two contributed papers to ICHEP94. Both papers relate to charm meson hadroproduction at Fermilab fixed target energies. The first (from E769) addresses the total forward cross section for charm mesons (D{sup {plus_minus}} and D{sub s}{sup {plus_minus}}) produced by {pi}{sup {plus_minus}}, K{sup {plus_minus}}, and proton beams. The second paper (from E791) deals with the asymmetries in the differential cross sections for charged D mesons produced in the forward direction by {pi}{sup {minus}} beam. The physics most directly related to the results of the E769 paper are the gluon distributions in the incident hadrons as well as perturbative QCD calculations of charm quark production and the charm quark mass. The E791 results address the details of the hadronization process after production of the charm quarks.

Study of Xic -> pKpi reconstruction with the ALICE experiment

CERN Document Server

Joerg, Florian

2015-01-01

Heavy-ion collisions at high energies provide an insight into the behavior of strongly interacting matter. It is predicted that a new state of matter, the so called Quark Gluon Plasma (QGP) forms at the high temperature and energy density reached in these collisions. Hadron formation via coalescence of charm quarks with light quarks from the QGP can enhance the production of of charm baryons and charm hadrons with strangeness. The Xic baryon is a charmed and strange baryon. The measurement of its production yield can give essential information about the produced medium. This work is a feasibility study for the reconstruction of the Xic -> pKpi decay channel using the ALICE detector. A dedicated Monte Carlo simulation which included the decay channel under study was done in order to develop an analysis strategy that makes use of particle identification (PID) methods and exploits the typical displaced topology of the decay. A loose set of cuts aiming for a high signal efficiency was defined and applied on d...

Constraints on atmospheric charmed-meson production from IceCube

Directory of Open Access Journals (Sweden)

Palczewski Tomasz Jan

2016-01-01

Full Text Available At very-high energies (100 TeV - 1 PeV, the small value of Bjorken-x (≤ 10−3 − 10−7 at which the parton distribution functions are evaluated makes the calculation of charm quark production very difficult. The charm quark has mass (~1.5±0.2 GeV significantly above the ΛQCD scale (~200 MeV, and therefore its production is perturbatively calculable. However, the uncertainty in the data and the calculations cannot exclude some smaller non-perturbative contribution. To evaluate the prompt neutrino flux, one needs to know the charm production cross-section in pN -> cc̄ X, and hadronization of charm particles. This contribution briefly discusses computation of prompt neutrino flux and presents the strongest limit on prompt neutrino flux from IceCube.

Proceedings of the 2-nd workshop on JINR tau-charm factory

International Nuclear Information System (INIS)

Aleksandrov, V.S.; Perel'shtejn, E.A.

1993-01-01

Application of tau-charm factory for investigation of hadronic decay and charged leptonic weak interaction is considered. JINR tau-charm-factory design and magnetic and vacuum systems of the booster ring are described. New types of silicon microstrip detector sand BGO-counters developed for tau-charm-factory are proposed

Study of Events with Identified Forward Particles at the Split Field Magnet

CERN Multimedia

2002-01-01

This experiment will study two aspects of particle production in the forward region : \\item 1) In the recent discovery of charm production in hadronic interactions at the Split Field Magnet, the triggering on strange particles at medium p^t has proven to be a very effective tool for the study of heavy resonances, especially those carrying new flavours like charm and beauty. We want to carry out a more detailed investigation of the production-dynamics of charmed particles, together with a search for beauty mesons and baryons. \\item 2) A trigger on forward particles at high p^t ($>$ 5GeV/c) provides unique features to determine the properties of the parton-parton subprocesses. We want to study the relative contributions of quark, diquark and gluon scattering.\\\\ \\\\ This experimental programme will be carried out, using the improved Split Field Magnet spectrometer (SFM). The different detection systems provide : \\item a) Detection and momentum analysis of charged particles in 4@p solid angle. An improved programm...

Beyond charm

International Nuclear Information System (INIS)

Harari, H.

1976-01-01

These lecture notes are devoted to the first glimpses that we have had into a new chapter that might be called ''beyond charm''. The main subjects treated are the problems of relating the quarks and leptons to each other and the unification of the weak electromagnetic and of the strong interactions. Some of the more technical features of two specific models are discussed. (B.G.)

B decays to wrong sign charm mesons at the DELPHI experiment

International Nuclear Information System (INIS)

Schwanda, C.

2001-05-01

In the present work, b hadron decays to 'wrong sign charm' mesons, b → D-bar 0 X, b → D - X and b → D s - X, are studied using the data collected by the DELPHI experiment in the years 1994 and 1995, and the corresponding branching fractions are extracted. Decays b → c-bar are expected to occur through the Cabibbo favored transitions b → cW - and W - → cbar s, and hence wrong sign charm decays are in fact double charm transitions. The interest in this type of b decays is triggered by different motivations. At first, wrong sign charm decays provide evidence for an alternative mechanism leading to the production of charmed mesons in b decay ('upper vertex charm'), and, second, the double charm rate is related to n c , the mean number of charm quarks (and anti-quarks) produced per b decay, n c =1 + Br(b → c c-bar s). Predictions of the semileptonic B meson branching fraction, based on the heavy quark effective theory (HQET) and the heavy quark expansion (HQE), also fix the value of n c . By measuring the double charm rate, we can thus probe these predictions. The measurement of the inclusive wrong sign branching fractions proceeds through the following steps: At first, the charmed meson decays D 0 → K - π + , D + → K - π + π + and D s + → φ π + → K + K - π + are exclusively reconstructed in the DELPHI data. The charge of the c quark confined inside the charmed meson is determined by the charge of the kaon (D 0 , D + ) or by the charge of the pion (D s + ). The b quark charge at decay time in the charmed meson hemisphere is estimated by using identified particles. A neural network approach is adopted. By correlating both charge informations, we obtain the main discriminant variable for selecting wrong sign mesons. We measure the following branching ratios: Br(b → D-bar X)=(9.3 ± 1.7(stat) ± 1.3(syst))% and Br(b → D s - X)=(10.3 ± 1.1(stat) ± 2.9(syst))% (the first error is statistical, the second one systematic). This result is

Charm and strange quark contributions to the proton structure

International Nuclear Information System (INIS)

Torokoff, K.

1999-02-01

The possibility to have charm and strange quarks as quantum mechanical fluctuations in the proton wave function is investigated based on a model for non-perturbative QCD dynamics. Both hadron and parton basis are examined. A scheme for energy fluctuations is constructed and compared with explicit energy-momentum conservation. Resulting momentum distributions for charm and strange quarks in the proton are derived at the starting scale Q 0 for the perturbative QCD evolution. Kinematical constraints are found to be important when comparing to the 'intrinsic charm' model

The three good brothers charm : some historical points / Lea Olsan

Index Scriptorium Estoniae

Olsan, Lea T.

2011-01-01

Ravimise loitsudest: keskajal levinud legendaarsest kolme venna (tres boni fratres - lad. k.) loitsust haava parandamiseks; ettekanne rahvusvahelisel konverentsil "Charms, charmers and charming" Bukarestis 2010. a.

Tagging charm with decay lengths

International Nuclear Information System (INIS)

Reay, N.W.

1982-01-01

With much detail, the author of this selection discusses two experiments which use the same physics but in different ways to obtain one same goala background - free sample of charm decays. One of the major purposes of gaining this sample is to measure one lifetime for charmed particles and to locate new particles. Continuing to discuss the first experiment, the Fermilab Experiment + 531, the author describes its methods, philosophy and two unexpected effects of the experiment. He turns then to discuss the CERN NA-15 experiment, describing its methods, findings and difficulties. Concluding his discussion on a positive note, the author is hopeful for the plans to continue more experimentation

arXiv Mixing and CPV in charm hadrons at LHCb

CERN Document Server

INSPIRE-00437507

2018-05-03

LHCb continues to expand its world-leading sample of charmed hadrons collected during LHCs Run 1 (2010-2012) and Run 2 (2015-present). This sample is yielding some of the most stringent tests of the Standard Model understanding of charm physics. This includes precise measurements of the neutral D-meson mixing parameters and some of the most sensitive searches for direct and indirect CP violation in charm interactions.

Triggers for a high sensitivity charm experiment

International Nuclear Information System (INIS)

Christian, D.C.

1994-07-01

Any future charm experiment clearly should implement an E T trigger and a μ trigger. In order to reach the 10 8 reconstructed charm level for hadronic final states, a high quality vertex trigger will almost certainly also be necessary. The best hope for the development of an offline quality vertex trigger lies in further development of the ideas of data-driven processing pioneered by the Nevis/U. Mass. group

Measurement of the inclusive decay properties of charmed mesons

Energy Technology Data Exchange (ETDEWEB)

Coffman, D; DeJongh, F; Dubois, G; Eigen, G; Hitlin, D G; Matthews, C G; Mincer, A; Richman, J D; Wisniewski, W J; Zhu, Y [California Inst. of Tech., Pasadena, CA (United States); Bai, Z; Burchell, M; Dorfan, D E; Drinkard, J D; Gatto, C; Heusch, C A; Lockman, W S; Partridge, R; Sadrozinski, H F.W.; Scarlatella, M; Schalk, T L; Seiden, A; Weinstein, A J; Weseler, S; Xu, R [Univ. of California, Santa Cruz, CA (United States); Brown, J S; Eisenstein, B I; Freese, T; Gladding, G; Izen, J M; Simopoulos, C; Stockdale, I E; Tripsas, B [Univ. of Illinois, Urbana-Champaign, IL (United States); Mallik, U; Wang, M Z [Univ. of Iowa, Iowa City, IA (United States); Bolten, T; Browder, T E; Bunnell, K O; Cassell, R E; Coward, D H; Dado, S; Grab, C; Kim, P C; Labs, J; Odian, A; Pitman, D; Schindler, R H; Toki, W; Villa, F; Wasserbaech, S; Wisinski, D [Stanford Linear Accelerator Center, Stanford Univ., CA (United States); Burnett, T H; Cook,; MARK III Collaboration

1991-07-04

We report a high statistics study of the inclusive decay properties of the charmed D{sup 0} and D{sup +} mesons, and the first inclusive study of the charmed D{sub s}{sup +}. The data are collected at {radical}s = 3.77 GeV and {radical}s = 4.14 GeV with the Mark III detector at the e{sup +}e{sup -} storage ring SPEAR. For each charmed meson species, the charged-particle multiplicity, the strangeness content of the final state, and the average {pi}{sup 0} multiplicity are determined. (orig.).

Charm and strange quark contributions to the proton structure

Energy Technology Data Exchange (ETDEWEB)

Torokoff, K

1999-02-01

The possibility to have charm and strange quarks as quantum mechanical fluctuations in the proton wave function is investigated based on a model for non-perturbative QCD dynamics. Both hadron and parton basis are examined. A scheme for energy fluctuations is constructed and compared with explicit energy-momentum conservation. Resulting momentum distributions for charm and strange quarks in the proton are derived at the starting scale Q{sub 0} for the perturbative QCD evolution. Kinematical constraints are found to be important when comparing to the `intrinsic charm` model 20 refs, 30 figs, 9 tabs

Neutrino Charm Production and a Limit to Neutrino Oscillations

Energy Technology Data Exchange (ETDEWEB)

Bailey, David Charles [McGill U.

1983-10-01

The production of charmed particles and a limit to tau lepton production have been measured using a hybrid emulsion spectrometer in the Fermilab wide-band neutrino beam. The relative cross section for charged current charmed particle production is $\\sigma(\

Physics of a high-luminosity Tau-Charm Factory

International Nuclear Information System (INIS)

King, M.E.

1992-10-01

This paper highlights the physics capabilities of a Tau-Charm Factory; i.e., high luminosity (∼10 33 cm -2 s -1 ) e + e - collider operating in the center-of-mass energy range of 3-5 GeV, with a high-precision, general-purpose detector. Recent developments in τ and charm physics are emphasized

submitter Time-dependent CP violation in charm mesons

CERN Document Server

Inguglia, Gianluca

CP violation is a well established phenomenon for B and K mesons, but for D0 mesons, bound states made up of a quark-antiquark pair containing a charm quark, a conclusive answer to the question whether there is CP vio- lation or not, has yet to be determined. I show here the phenomenology of time-dependent CP asymmetries in charm decays, and discuss the implica- tions of experimental tests aimed at the measurement of CP violation in the interference between mixing and decays of charm mesons, in particular when studying the decay channels D0 ! h+h (h = K; ). The decay channels considered can also be used to constrain quantities that are poorly measured or still to be investigated, such as MIX and c;eff , provided that the e ects of penguin pollution are ignored. I considered correlated production of D0 mesons at the SuperB experiment and its planned asymmetric run at the charm threshold and performed a study of simulated events, nding that a boost factor = 0:28 would not be su cient to produce competitive re- ...

Charm and beauty production at CDF

Energy Technology Data Exchange (ETDEWEB)

Bishai, M.; /Brookhaven

2005-01-01

Using the data samples collected with the CDF Run II detector during 2002 and early 2003, new measurements of the production cross sections of charm and beauty hadrons at {radical}s = 1960 GeV are presented. New measurements of the cross sections of centrally produced b-hadrons and J/{psi} mesons down to zero transverse momenta have been carried out. The large charm signals made available by the silicon vertex track trigger have enabled the measurement of the cross sections of D{sup 0}, D*, D{sup {+-}}, and D{sub s} mesons.

Study of heavy flavored particles

International Nuclear Information System (INIS)

1991-01-01

This report discusses progress on the following topics: time-of- flight system; charmed baryon production and decays; D decays to baryons; measurement of sigma plus particles magnetic moments; and strong interaction coupling

New forces and the 750 GeV resonance

International Nuclear Information System (INIS)

Duerr, Michael; Fileviez Perez, Pavel; Smirnov, Juri

2016-04-01

Recently, the ATLAS and CMS collaborations have pointed out the possible existence of a new resonance with a mass around 750 GeV. We investigate the possibility to identify this new resonance with a spin zero field responsible for the breaking of a new gauge symmetry. We focus on a simple theory where the baryon number is a local symmetry spontaneously broken at the low scale. In this context new vector-like quarks are needed to cancel all baryonic anomalies and define the production mechanism and decays of the new Higgs at the LHC. Assuming the existence of the new Higgs with a mass of 750 GeV at the LHC we find an upper bound on the symmetry breaking scale. Therefore, one expects that a new force associated with baryon number could be discovered at the LHC.

Probing new physics in rare charm processes

International Nuclear Information System (INIS)

Hewett, J.L.

1994-09-01

The possibility of using the charm system to search for new physics is addressed. Phenomena such as D 0 - bar D 0 mixing and rare decays of charmed mesons are first examined in the Standard Model to test the present understanding and to serve as benchmarks for signals from new sources. The effects of new physics from various classes of non-standard dynamical models on D 0 - bar D 0 mixing are investigated

Baryonic matter and beyond

OpenAIRE

Fukushima, Kenji

2014-01-01

We summarize recent developments in identifying the ground state of dense baryonic matter and beyond. The topics include deconfinement from baryonic matter to quark matter, a diquark mixture, topological effect coupled with chirality and density, and inhomogeneous chiral condensates.

A quark model of baryons with natural flavor

International Nuclear Information System (INIS)

Forsyth, C.P.; Cutkowsky, R.E.

1983-01-01

We have fitted the masses and elastic widths of the S=0 baryons in the context of the QCD-improved quark shell model. All states in the N=0, 1, 2 and 3 harmonic oscillator bands have been included. Three models for the decay of these states have been studied, and it is concluded that the usual spectator model for the decays must be modified. Many resonances in the N=2 and 3 bands were found to decouple from the πN channel, supporting a previous solution to the missing resonance puzzle. No evidence has been found for the tensor force, while conflicting data exist for the 3-body spin orbit term. We also have found evidence that the contact force varies with band. The (56,1 - ) multiplet is lower than expected. (orig.)

Baryon-baryon bound states from first principles in 3+1 lattice QCD with two flavors and strong coupling

International Nuclear Information System (INIS)

Faria da Veiga, Paulo A.; O'Carroll, Michael

2006-01-01

We determine baryon-baryon bound states in (3+1)-dimensional SU(3) lattice QCD with two flavors, 4x4 spin matrices, and in an imaginary time formulation. For small hopping parameter κ>0 and large glueball mass (strong coupling), we show the existence of three-quark isospin 1/2 particles (proton and neutron) and isospin 3/2 baryons (delta particles), with asymptotic masses -3lnκ and isolated dispersion curves. Baryon-baryon bound states of isospin zero are found with binding energy of order κ 2 , using a ladder approximation to a lattice Bethe-Salpeter equation. The dominant baryon-baryon interaction is an energy-independent spatial range-one attractive potential with an O(κ 2 ) strength. There is also attraction arising from gauge field correlations associated with six overlapping bonds, but it is counterbalanced by Pauli repulsion to give a vanishing zero-range potential. The overall range-one potential results from a quark, antiquark exchange with no meson exchange interpretation; the repulsive or attractive nature of the interaction depends on the isospin and spin of the two-baryon state

Tetraquarks in the 1/N expansion and meson-meson resonances

Energy Technology Data Exchange (ETDEWEB)

Maiani, L. [Dipartimento di Fisica and INFN, ‘Sapienza’ Università di Roma, P.le Aldo Moro 5, I-00185 Roma (Italy); Polosa, A.D. [Dipartimento di Fisica and INFN, ‘Sapienza’ Università di Roma, P.le Aldo Moro 5, I-00185 Roma (Italy); CERN Theory Department, CH-1211 Geneva 23 (Switzerland); Riquer, V. [Dipartimento di Fisica and INFN, ‘Sapienza’ Università di Roma, P.le Aldo Moro 5, I-00185 Roma (Italy)

2016-06-27

Diquarks are found to have the right degrees of freedom to describe the tetraquark poles in hidden-charm to open-charm meson-meson amplitudes. Compact tetraquarks result as intermediate states in non-planar diagrams of the 1/N expansion and the corresponding resonances are narrower than what estimated before. The proximity of tetraquarks to meson-thresholds has an apparent role in this analysis and, in the language of meson molecules, an halving rule in the counting of states is obtained.

Tetraquarks in the 1/N expansion and meson-meson resonances

International Nuclear Information System (INIS)

Maiani, L.; Polosa, A.D.; Riquer, V.

2016-01-01

Diquarks are found to have the right degrees of freedom to describe the tetraquark poles in hidden-charm to open-charm meson-meson amplitudes. Compact tetraquarks result as intermediate states in non-planar diagrams of the 1/N expansion and the corresponding resonances are narrower than what estimated before. The proximity of tetraquarks to meson-thresholds has an apparent role in this analysis and, in the language of meson molecules, an halving rule in the counting of states is obtained.

Charming penguin and direct CP-violation in charmless B decays

International Nuclear Information System (INIS)

Pham, T.N.

2003-01-01

In the study of two-body charmless B decays as a mean of looking for direct CP-violation and measuring the CKM mixing parameters in the standard Model, the short-distance penguin contribution with its absorptive part generated by charm quark loop seems capable of producing sufficient B → Kπ decays rates, as obtained in factorization and QCD-improved factorization models. However there are also long-distance charming penguin contributions which could give rise to a strong phase due to the rescattering D * D * → Kπ etc. In this talk, I would like to discuss recent works on the charming penguin contribution as a different approach to the calculation of these contributions in two-body charmless B decays. We find that the charming penguin contribution is significant for B → Kπ decays and, together with the tree and penguin terms, produces large branching ratios in agreement with data, though the analysis is affected by large theoretical uncertainties. The absorptive part due to the charmed meson intermediate states is found to produce large CP asymmetries for B → Kπ, ππ decays

Predictions for the decays of radially-excited baryons

International Nuclear Information System (INIS)

Carlson, C.E.

2001-01-01

We consider decays of the lowest-lying radially excited baryons. Assuming a single-quark decay approximation, and negligible configuration mixing, we make model-independent predictions for the partial decay widths to final states with a single meson. Masses of unobserved states are predicted using an old mass formula rederived using large-N c QCD. The momentum dependence of the one-body decay amplitude is determined phenomenologically by fitting to observed decays. Comparison of these predictions to experiment may shed light on whether the Roper resonance can be interpreted as a three-quark state. (author)

Ω{sub c} excited states within a SU(6){sub lsf} x HQSS model

Energy Technology Data Exchange (ETDEWEB)

Nieves, J.; Pavao, R. [Instituto de Fisica Corpuscular (Centro mixto CSIC-UV), Institutos de Investigacion de Paterna, Valencia (Spain); Tolos, L. [University of Frankfurt, Institut fuer Theoretische Physik, Frankfurt am Main (Germany); University of Frankfurt, Frankfurt Institute for Advanced Studies, Frankfurt am Main (Germany); Institute of Space Sciences (ICE, CSIC), Campus UAB, Carrer de Can Magrans, Barcelona (Spain); Institut d' Estudis Espacials de Catalunya (IEEC), Barcelona (Spain)

2018-02-15

We have reviewed the renormalization procedure used in the unitarized coupled-channel model of Romanets et al. (Phys Rev D 85:114032, 2012), and its impact in the C = 1, S = -2, and I = 0 sector, where five Ω{sub c}{sup (*)} states have been recently observed by the LHCb Collaboration. The meson-baryon interactions used in the model are consistent with both chiral and heavy-quark spin symmetries, and lead to a successful description of the observed lowest-lying odd parity resonances Λ{sub c}(2595) and Λ{sub c}(2625), and Λ{sub b}(5912) and Λ{sub b}(5920) resonances. We show that some (probably at least three) of the states observed by LHCb will also have odd parity and J = 1/2 or J = 3/2, belonging two of them to the same SU(6){sub light-spin-flavor} x HQSS multiplets as the latter charmed and beauty Λ baryons. (orig.)

Virtual meson cloud of the nucleon and intrinsic strangeness and charm

International Nuclear Information System (INIS)

Navarra, F.S.; Nielsen, M.; Duraes, F.O.; Barz, L.L.; Paiva, S.

1996-09-01

We have applied the Meson Cloud Model (MCM) to calculate the charm and strange antiquark distribution in the nucleon. The resulting distribution, in the case of charm, is very similar to the intrinsic charm momentum distribution in the nucleon. This seems to corroborate the hypothesis that the intrinsic charm is in the cloud and, at the same time, explains why other calculations with the MCM involving strange quark distributions fail in reproducing the low x region data. From the intrinsic strange distribution in the nucleon we have extracted the strangeness radius of the nucleon, which is in agreement with other meson cloud calculations. (author). 28 refs., 4 figs

Charm production and the confining force field

International Nuclear Information System (INIS)

Andersson, B.; Bengtsson, H.-U.; Gustafson, G.

1983-03-01

We show that charm production at SPS energies can be understood simply from O(α 2 sub (s)) QCD processes when combined with fragmentation of the colour fields stretched by the final state partons. The tension of the confining force field responsible for particle production is found to pull the charmed particles away from the reaction centre, giving rise to a harder x sub (F)-spectrum than would be expected from the bare QCD matrix elements. (Authors)

Hadroproduction of charm at Fermilab E769

International Nuclear Information System (INIS)

Alves, G.A.; Anjos, J.C.; de Mello Neto, J.R.T.; de Miranda, J.M.; da Motta, H.; dos Reis, A.C.; Santoro, A.F.S.; Souza, M.H.G.; Appel, J.A.; Dixon, R.L.; Fenker, H.C.; Green, D.R.; Kwan, S.; Lueking, L.H.; Mantsch, P.M.; Spalding, W.J.; Stoughton, C.; Streetman, M.E.; Bracker, S.B.; Gay, C.; Jedicke, R.; Luste, G.J.; Cremaldi, L.M.; Summers, D.J.; Errede, D.; Sheaff, M.; Kaplan, D.; Leedom, I.; Reucroft, S.; Karchin, P.E.; Ross, W.R.; Wu, Z.; Metheny, J.; Milburn, R.H.; Napier, A.; de Oliveira, A.B.

1990-01-01

Experiment E769 at Fermilab obtained charm hadroproduction data during the 1987-88 Fixed Target running period with a 250 GeV hadron beam incident on thin target foils of Be, Al, Cu, and W. From an analysis of 25% of the recorded 400M trigger sample we have explored the Feynman x, p t 2 and the atomic number dependence of charm quark production using samples of D + and D 0 mesons. 7 refs., 4 figs

Prediction of super-heavy N⁎ and Λ⁎ resonances with hidden beauty

International Nuclear Information System (INIS)

Wu Jiajun; Zhao Lu; Zou, B.S.

2012-01-01

The meson-baryon coupled channel unitary approach with the local hidden gauge formalism is extended to the hidden beauty sector. A few narrow N ⁎ and Λ ⁎ resonances around 11 GeV are predicted as dynamically generated states from the interactions of heavy beauty mesons and baryons. Production cross sections of these predicted resonances in pp and ep collisions are estimated as a guide for the possible experimental search at relevant facilities.

Role of "intrinsic charm" in semileptonic B-meson decays

CERN Document Server

Breidenbach, C; Mannel, T; Turczyk, S

2008-01-01

We discuss the role of so-called "intrinsic-charm" operators in semi-leptonic B-meson decays, which appear first at order 1/m_b^3 in the heavy quark expansion. We show by explicit calculation that -- at scales mu <= m_c -- the contributions from "intrinsic-charm" effects can be absorbed into short-distance coefficient functions multiplying, for instance, the Darwin term. Then, the only remnant of "intrinsic charm" are logarithms of the form ln(m_c^2/m_b^2), which can be resummed by using renormalization-group techniques. As long as the dynamics at the charm-quark scale is perturbative, alpha_s(m_c) << 1, this implies that no additional non-perturbative matrix elements aside from the Darwin and the spin-orbit term have to be introduced at order 1/m_b^3. Hence, no sources for additional hadronic uncertainties have to be taken into account. Similar arguments may be made for higher orders in the 1/m_b expansion.

Determination of baryon-baryon elastic scattering phase shift from finite volume spectra in elongated boxes

Science.gov (United States)

Li, Ning; Wu, Ya-Jie; Liu, Zhan-Wei

2018-01-01

The relations between the baryon-baryon elastic scattering phase shifts and the two-particle energy spectrum in the elongated box are established. We studied the cases with both the periodic boundary condition and twisted boundary condition in the center of mass frame. The framework is also extended to the system of nonzero total momentum with periodic boundary condition in the moving frame. Moreover, we discussed the sensitivity functions σ (q ) that represent the sensitivity of higher scattering phases. Our analytical results will be helpful to extract the baryon-baryon elastic scattering phase shifts in the continuum from lattice QCD data by using elongated boxes.

Density-dependent effective baryon–baryon interaction from chiral three-baryon forces

Energy Technology Data Exchange (ETDEWEB)

Petschauer, Stefan, E-mail: stefan.petschauer@ph.tum.de [Physik Department, Technische Universität München, D-85747 Garching (Germany); Haidenbauer, Johann [Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, D-52425 Jülich (Germany); Kaiser, Norbert [Physik Department, Technische Universität München, D-85747 Garching (Germany); Meißner, Ulf-G. [Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron Physics, Forschungszentrum Jülich, D-52425 Jülich (Germany); Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, D-53115 Bonn (Germany); Bethe Center for Theoretical Physics, Universität Bonn, D-53115 Bonn (Germany); Weise, Wolfram [Physik Department, Technische Universität München, D-85747 Garching (Germany)

2017-01-15

A density-dependent effective potential for the baryon–baryon interaction in the presence of the (hyper)nuclear medium is constructed, based on the leading (irreducible) three-baryon forces derived within SU(3) chiral effective field theory. We evaluate the contributions from three classes: contact terms, one-pion exchange and two-pion exchange. In the strangeness-zero sector we recover the known result for the in-medium nucleon–nucleon interaction. Explicit expressions for the ΛN in-medium potential in (asymmetric) nuclear matter are presented. Our results are suitable for implementation into calculations of (hyper)nuclear matter. In order to estimate the low-energy constants of the leading three-baryon forces we introduce the decuplet baryons as explicit degrees of freedom and construct the relevant terms in the minimal non-relativistic Lagrangian. With these, the constants are estimated through decuplet saturation. Utilizing this approximation we provide numerical results for the effect of the three-body force in symmetric nuclear matter and pure neutron matter on the ΛN interaction. A moderate repulsion that increases with density is found in comparison to the free ΛN interaction.

Flavour and spin structure of linear baryons

International Nuclear Information System (INIS)

Kawarabayashi, K.; Kitakado, S.; Inami, T.

1979-01-01

Based on the string picture, a phenomenological model for baryons is constructed and their flavour symmetry, exchange degeneracy pattern and spin structure are studied. Baryons on leading trajectories are assumed to have the configuration of two quarks being attached to the ends of a linear string and the third sitting in the middle, called linear baryons. For such linear baryons, a unitarization scheme can be constructed in a manner similar to the dual unitarity scheme for mesons but without recourse to the 1/N expansion. It is found that the interchange interaction of the middle quark with one of the other two quarks at the ends of the string can give rise to a larger exchange degeneracy breaking of the baryon spectrum. With this non-planar correction, the model of linear baryons can account for the observed pattern of leading baryon states. (Auth.)

Measurement of $\\Lambda_{\\rm c}$ Baryon production in the decay channel $\\Lambda_{\\rm c} \\rightarrow p \\rm K^{0}_{\\rm S}~$ in proton-proton and proton-lead collisions with ALICE detector at LHC

CERN Document Server

Meninno, Elisa

This thesis describes the study of the production of the charmed baryon $\\Lambda_{\\rm c}^{+}$ in proton-proton and proton-lead collisions with the ALICE experiment, operating at the Large Hadron Collider (LHC) at CERN. ALICE was built to study hadronic collisions (pp and A-A) and, in particular, aims to investigate the $Quark-Gluon Plasma$ (QGP), state of the matter during the first instants of life of the universe. When two ultra-relativistic heavy nuclei collide, the extreme conditions of temperature and pressure, necessary for the QGP formation, can be created. In particular, heavy quarks (charm and beauty) are produced in hard scattering processes during the first stages of the hadronic collision. The measurement of hadrons with heavy quarks in pp collisions at the LHC energies is a powerful test for perturbative quantum cromodynamics (pQCD) in this energy domain. Moreover, these studies are the necessary reference for studying the production of heavy quarks in nucleus-nucleus collisions. Results from pp ...

B decays to baryons

Indian Academy of Sciences (India)

We note that two-body decays to baryons are suppressed relative to three- and four-body decays. In most of these analyses, the invariant baryon–antibaryon mass shows an enhancement near the threshold. We propose a phenomenological interpretation of this quite common feature of hadronization to baryons.

Measurement of charm in charged current at HERA

International Nuclear Information System (INIS)

Zimmermann, Tobias

2008-12-01

A measurement of charm production in charged current (CC) polarized electron-proton deep inelastic scattering processes with data from the H1 detector at the HERA collider is presented. This process in principle allows access to the strange quark density in the proton. In total 5460 CC candidate events in e + p and 6253 in e - p data are selected in the kinematic range Q 2 >223 GeV 2 and 0.03 CC =(28.9± 1.4)+P e .(28.6±4.7) pb for e + p and σ CC =(49.2±2.3)-P e .(42.5 ±6.8) pb for e - p, where P e is the lepton beam polarization. While the measured cross section for e + p data is in agreement with the theoretical prediction, the cross section for e - p data shows a weaker dependence on P e than predicted. The charm fractions in the selected CC candidate event samples are extracted using the muon charge asymmetry. Muons originating from charmed hadron decays in CC events at HERA always have the same charge as the beam lepton. The extracted charm fractions in the selected CC candidate event samples are F c =9.5±8.9±3.0 % for e + p and F c =4.4±6.9±2.6 % for e - p. Due to the large statistical errors of the measured charm fractions, the strange quark density in the proton has not been extracted. (orig.)

Charm production asymmetries at the Fermilab experiments

International Nuclear Information System (INIS)

Carter, T.

1997-01-01

I present asymmetries between the production of charm particles and anti-particles from Fermilab experiments, E687, E769 and E791. The results are shown as a function of x F and p t 2 for D ± and D s ± mesons and for pion, kaon and photon beams and compared against current models. Results are also shown for a recent analysis of correlations between production of charm mesons and an associated pion. 14 refs., 5 figs., 3 tabs

Quark color-hyperfine interactions in baryons

International Nuclear Information System (INIS)

Anselmino, M.; Lichtenberg, D.B.

1990-01-01

We consider the contribution from the color-hyperfine interaction to the energies of groundstate hadrons, with an emphasis on baryons. We use experimental information about how the color-hyperfine term depends on flavor to make predictions about the masses of baryons containing a heavy quark. We then generalize some relations between color-hyperfine matrix elements in mesons and baryons to obtain a number of additional predictions about the masses of as-yet unobserved baryons. Most of our predictions are in the form of inequalities. (orig.)

CT14 intrinsic charm parton distribution functions from CTEQ-TEA global analysis

Science.gov (United States)

Hou, Tie-Jiun; Dulat, Sayipjamal; Gao, Jun; Guzzi, Marco; Huston, Joey; Nadolsky, Pavel; Schmidt, Carl; Winter, Jan; Xie, Keping; Yuan, C.-P.

2018-02-01

We investigate the possibility of a (sizable) nonperturbative contribution to the charm parton distribution function (PDF) in a nucleon, theoretical issues arising in its interpretation, and its potential impact on LHC scattering processes. The "fitted charm" PDF obtained in various QCD analyses contains a process-dependent component that is partly traced to power-suppressed radiative contributions in DIS and is generally different at the LHC. We discuss separation of the universal component of the nonperturbative charm from the rest of the radiative contributions and estimate its magnitude in the CT14 global QCD analysis at the next-to-next-to leading order in the QCD coupling strength, including the latest experimental data from HERA and the Large Hadron Collider. Models for the nonperturbative charm PDF are examined as a function of the charm quark mass and other parameters. The prospects for testing these models in the associated production of a Z boson and a charm jet at the LHC are studied under realistic assumptions, including effects of the final-state parton showering.

Meson-baryon-baryon vertex function and the Ward-Takahashi identity

International Nuclear Information System (INIS)

Wang, S.; Banerjee, M.K.

1996-01-01

Ohta proposed a solution for the well-known difficulty of satisfying the Ward-Takahashi identity for a photo-meson-baryon-baryon amplitude (γMBB) when a dressed meson-baryon-baryon (MBB) vertex function is present. He obtained a form for the γMBB amplitude which contained, in addition to the usual pole terms, longitudinal seagull terms which were determined entirely by the MBB vertex function. He arrived at his result by using a Lagrangian which yields the MBB vertex function at tree level. We show that such a Lagrangian can be neither Hermitian nor charge conjugation invariant. We have been able to reproduce Ohta close-quote s result for the γMBB amplitude using the Ward-Takahashi identity and no other assumption, dynamical or otherwise, and the most general form for the MBB and γMBB vertices. However, contrary to Ohta close-quote s finding, we find that the seagull terms are not robust. The seagull terms extracted from the γMBB vertex occur unchanged in tree graphs, such as in an exchange current amplitude. But the seagull terms which appear in a loop graph, as in the calculation of an electromagnetic form factor, are, in general, different. The whole procedure says nothing about the transverse part of the (γMBB) vertex and its contributions to the amplitudes in question. copyright 1996 The American Physical Society

Discrete ambiguity resolution and baryon-resonance parameter determination

International Nuclear Information System (INIS)

Chew, D.M; Urban, M.

1978-04-01

A partial-wave analysis was performed on elastic π + p data between 1400 and 2200 MeV, using principles of analyticity (to select and amalgamate data), causality and unitarity together with Barrelet zeros are the resonating waves between 1500 and 1800 MeV examined in detail, and it is shown how a new resolution of the discrete ambiguity gives, for the S31 and D33 resonances, different parameters than found in an earlier resolution using less accurate information. In either case, mass degeneracy of these resonances is observed in agreement with general considerations regarding smooth zero trajectories. 18 references

Hadroproduction and photoproduction of beauty and charm in fixed-target experiments

International Nuclear Information System (INIS)

Slaughter, J.

1996-01-01

The authors summarize the current experimental situation for charm and beauty production in fixed-target experiments. Particular emphasis is placed on beauty cross-sections and charm pair correlations

Baryon number violation and string topologies

International Nuclear Information System (INIS)

Sjoestrand, T.; Skands, P.Z.

2003-01-01

In supersymmetric scenarios with broken R-parity, baryon number violating sparticle decays become possible. In order to search for such decays, a good understanding of expected event properties is essential. We here develop a complete framework that allows detailed studies. Special attention is given to the hadronization phase, wherein the baryon number violating vertex is associated with the appearance of a junction in the colour confinement field. This allows us to tell where to look for the extra (anti)baryon directly associated with the baryon number violating decay

Tetraquark operators in lattice QCD and exotic flavour states in the charm sector

Science.gov (United States)

Cheung, Gavin K. C.; Thomas, Christopher E.; Dudek, Jozef J.; Edwards, Robert G.

2017-11-01

We present a general class of operators resembling compact tetraquarks which have a range of colour-flavour-spin structures, transform irreducibly under the symmetries of the lattice and respect other relevant symmetries. These constructions are demonstrated in lattice QCD calculations with light quarks corresponding to m π = 391 MeV. Using the distillation framework, correlation functions involving large bases of meson-meson and tetraquark operators are computed in the isospin-1 hidden-charm and doubly-charmed sectors, and finite-volume spectra are extracted with the variational method. We find the spectra are insensitive to the addition of tetraquark operators to the bases of meson-meson operators. For the first time, through using diverse bases of meson-meson operators, the multiple energy levels associated with meson-meson levels which would be degenerate in the non-interacting limit are extracted reliably. The number of energy levels in each spectrum is found to be equal to the number of expected non-interacting meson-meson levels in the energy region considered and the majority of energies lie close to the non-interacting levels. Therefore, there is no strong indication for any bound state or narrow resonance in the channels we study.

Charms - Kudu - Heinsaar kui sibul - kala - munaroog / Jüri Ehlvest

Index Scriptorium Estoniae

Ehlvest, Jüri, 1967-2006

2005-01-01

K. Kudust ja tema kolmest lavastusest Tartu Üliõpilasteatri esituses : M. Heinsaar-D. Charms-L. Carroll "Artur ja Paul ehk veidi enne maailma loomist", M. Heinsaar-D. Charms "Joogem äädikat, härrased!" ja D. Charmsi "Jelizaveta Bam"

Diquark structure of baryons

International Nuclear Information System (INIS)

Silvestre-Brac, B.

1987-01-01

Three body calculations for studying the baryons are performed in a non-relativistic treatment with three quarks interacting via Bhaduri's potential. From the resulting wave functions, it is analysed under which conditions can a diquark structure occurs. Several photos showing quark distributions inside the baryons are presented and discussed in details

Lifetimes of charm and beauty hadrons

International Nuclear Information System (INIS)

Bellini, G.; Dornan, P.J.

1997-01-01

Major breakthroughs have been achieved in the determination of the lifetimes of charm and beauty hadrons. Much larger data samples than previously have become available and new experimental devices and techniques have been developed and employed. The lifetimes of all weakly decaying singly charmed hadrons have been measured, some with an accuracy of a few percent. The difference in the shortest lifetime - τ(Ω c ) - and the longest one - τ(D + ) - is given by a factor of close to ten. The experimental status of beauty lifetimes, while less complete, has still reached a new level of quality and is now better than 5% for the commoner states. New theoretical tools, based mainly on heavy quark expansions, have been developed; they incorporate as well as transcend earlier phenomenological descriptions. The observed pattern in the charm lifetime ratios is reproduced in a semi-quantitative manner as well as could be expected; as far as the beauty lifetime ratios are concerned some problems may well be emerging. The maturity level achieved in the measurements bodes quite well for future challenges where reliable and efficient tracking of the decay vertices will be crucial. (orig.)

D{sub s1}{sup ∗}(2860) and D{sub s3}{sup ∗}(2860): candidates for 1D charmed-strange mesons

Energy Technology Data Exchange (ETDEWEB)

Song, Qin-Tao [Nuclear Theory Group, Institute of Modern Physics, Chinese Academy of Sciences, 730000, Lanzhou (China); Research Center for Hadron and CSR Physics, Lanzhou University & Institute of Modern Physics of CAS, 730000, Lanzhou (China); University of Chinese Academy of Sciences, 100049, Beijing (China); Chen, Dian-Yong, E-mail: chendy@impcas.ac.cn [Nuclear Theory Group, Institute of Modern Physics, Chinese Academy of Sciences, 730000, Lanzhou (China); Research Center for Hadron and CSR Physics, Lanzhou University & Institute of Modern Physics of CAS, 730000, Lanzhou (China); Liu, Xiang, E-mail: xiangliu@lzu.edu.cn [Research Center for Hadron and CSR Physics, Lanzhou University & Institute of Modern Physics of CAS, 730000, Lanzhou (China); School of Physical Science and Technology, Lanzhou University, 730000, Lanzhou (China); Matsuki, Takayuki, E-mail: matsuki@tokyo-kasei.ac.jp [Tokyo Kasei University, 1-18-1 Kaga, Itabashi, 173-8602, Tokyo (Japan); Theoretical Research Division, Nishina Center, RIKEN, 351-0198, Saitama (Japan)

2015-01-27

Newly observed two charmed-strange resonances, D{sub s1}{sup ∗}(2860) and D{sub s3}{sup ∗}(2860), are investigated by calculating their Okubo–Zweig–Iizuka-allowed strong decays, which shows that they are suitable candidates for the 1{sup 3}D{sub 1} and 1{sup 3}D{sub 3} states in the charmed-strange meson family. Our study also predicts other main decay modes of D{sub s1}{sup ∗}(2860) and D{sub s3}{sup ∗}(2860), which can be accessible at the future experiment. In addition, the decay behaviors of the spin partners of D{sub s1}{sup ∗}(2860) and D{sub s3}{sup ∗}(2860), i.e., 1D(2{sup -}) and 1D{sup ′}(2{sup -}), are predicted in this work, which are still missing at present. The experimental search for the missing 1D(2{sup -}) and 1D{sup ′}(2{sup -}) charmed-strange mesons is an intriguing and challenging task for further experiments.

Single spin asymmetry for charm mesons

Energy Technology Data Exchange (ETDEWEB)

Dominguez Zacarias, G. [PIMAyC, Eje Central Lazaro Cardenas No. 152, Apdo. Postal 14-805, D.F. (Mexico); Herrera, G.; Mercado, J. [Centro de Investigacion y de Estudios Avanzados, Apdo. Postal 14-740, D.F. (Mexico)

2007-08-15

We study single spin asymmetries of D{sup 0} and D{sup -} mesons in polarized proton-proton collisions. A two component model is used to describe charm meson production. The production of D mesons occurs by recombination of the constituents present in the initial state as well as by fragmentation of quarks in the final state. This model has proved to describe the production of charm. The recombination component involves a mechanism of spin alignment that ends up in a single spin asymmetry. Experimental measurements of single spin asymmetry for pions at RHIC are compared with the model. Predictions for the asymmetry in D mesons are presented. (orig.)

Single spin asymmetry for charm mesons

International Nuclear Information System (INIS)

Dominguez Zacarias, G.; Herrera, G.; Mercado, J.

2007-01-01

We study single spin asymmetries of D 0 and D - mesons in polarized proton-proton collisions. A two component model is used to describe charm meson production. The production of D mesons occurs by recombination of the constituents present in the initial state as well as by fragmentation of quarks in the final state. This model has proved to describe the production of charm. The recombination component involves a mechanism of spin alignment that ends up in a single spin asymmetry. Experimental measurements of single spin asymmetry for pions at RHIC are compared with the model. Predictions for the asymmetry in D mesons are presented. (orig.)

Looking for charming asymmetries

CERN Multimedia

Stefania Pandolfi

2016-01-01

New results presented by the LHCb collaboration on the decay of particles containing a “charm” quark delve deeper into the mystery of matter-antimatter asymmetry.   A view of the LHCb experimental cavern. (Photo: Maximilien Brice/CERN) One of the biggest challenges in physics is to understand why everything we see in our universe seems to be formed only of matter, whereas the Big Bang should have created equal amounts of matter and antimatter. CERN’s LHCb experiment is one of the best hopes for physicists looking to solve this longstanding mystery. At the VIII International Workshop on Charm Physics, which took place in Bologna earlier this month, the LHCb Collaboration presented the most precise measurement to date of a phenomenon called Charge-Parity (CP) violation among particles that contain a charm quark. CP symmetry states that laws of physics are the same if a particle is interchanged with its anti-particle (the “C” part) and if its spatia...

Charm studies in emulsion

CERN Document Server

Kalinin, Sergey

Neutrino-nucleon scattering is an effective way to investigate the inner structure of the nucleon, to extract the Standard Model parameters and to explore heavy quarks production dynamics. In the last decades, several experiments have been constructed to study weak interactions of neutrinos with nucleons. One of them was CERN-WA95 experiment operated by the CHORUS collaboration. It is based on a hybrid detector with nuclear emulsion as a target followed by electronic devices. Nuclear emulsion provides three dimensional spatial information with an outstanding resolution of the order of one micron. Therefore, it is ideal to detect short-lived particles. A special technique has been developed to reconstruct events in the emulsion which allows to perform a detailed investigation of events such as charmed hadrons production by neutrinos. As a result, the backround in the selected charm sample is up to six times lower compared to similar experiments. Such a method also permits to make direct measurements of some qu...

CP violation searches in the charm sector at LHCb

CERN Multimedia

CERN. Geneva

2016-01-01

LHCb has collected the world's largest sample of charmed hadrons, thus enabling measurements of direct and indirect CP violation parameters of D^0 mesons to be made with unprecedented precision. The difference in CP asymmetries between the singly Cabibbo-suppressed (SCS) D^0 -> K+K- and D^0 -> pi+pi- decays (Delta A_CP) has emerged as a powerful observable to search for direct CPV in the charm sector. By taking the difference between the two modes, most of the asymmetries induced by the detector or coming from the production mechanism are cancelled. The measurement of Delta A_CP done at LHCb is the most precise measurement of a time-integrated CP asymmetry in the charm sector from a single experiment, with a precision reaching the sub-permille level. Two independent measurements of Delta A_CP based on complementary data sets will be presented. Related 2-body searches and searches for direct CP violation in multi-body decays of the D^0 mesons will be discussed. Indirect CP violation in charm is measured throug...

QCD at Zero Baryon Density and the Polyakov Loop Paradox

CERN Document Server

Kratochvila, S; Forcrand, Ph. de

2006-01-01

We compare the grand canonical partition function at fixed chemical potential mu with the canonical partition function at fixed baryon number B, formally and by numerical simulations at mu=0 and B=0 with four flavours of staggered quarks. We verify that the free energy densities are equal in the thermodynamic limit, and show that they can be well described by the hadron resonance gas at T T_c. Small differences between the two ensembles, for thermodynamic observables characterising the deconfinement phase transition, vanish with increasing lattice size. These differences are solely caused by contributions of non-zero baryon density sectors, which are exponentially suppressed with increasing volume. The Polyakov loop shows a different behaviour: for all temperatures and volumes, its expectation value is exactly zero in the canonical formulation, whereas it is always non-zero in the commonly used grand-canonical formulation. We clarify this paradoxical difference, and show that the non-vanishing Polyakov loop e...

Self-energies of octet and decuplet baryons due to the coupling to the baryon-meson continuum

Energy Technology Data Exchange (ETDEWEB)

Garcia-Tecocoatzi, H. [INFN, Sezione di Genova, Genova (Italy); Universidad Nacional Autonoma de Mexico, Instituto de Ciencias Nucleares, Mexico (Mexico); Bijker, R. [Universidad Nacional Autonoma de Mexico, Instituto de Ciencias Nucleares, Mexico (Mexico); Ferretti, J. [Chinese Academy of Sciences, Institute of Theoretical Physics, Beijing (China); Dipartimento di Fisica, Universita di Roma Sapienza, Roma (Italy); INFN, Roma (Italy); Santopinto, E. [INFN, Sezione di Genova, Genova (Italy)

2017-06-15

We present an unquenched quark model calculation of the mass shifts of ground-state octet and decuplet baryons due to the coupling to the meson-baryon continuum. All ground-state baryons and pseudoscalar mesons are included in our calculation as intermediate states. The q anti q pair creation effects are taken explicitly into account through a microscopic, QCD-inspired, quark-antiquark pair creation mechanism. (orig.)

Measurement of charm in charged current at HERA

Energy Technology Data Exchange (ETDEWEB)

Zimmermann, Tobias

2008-12-15

A measurement of charm production in charged current (CC) polarized electron-proton deep inelastic scattering processes with data from the H1 detector at the HERA collider is presented. This process in principle allows access to the strange quark density in the proton. In total 5460 CC candidate events in e{sup +}p and 6253 in e{sup -}p data are selected in the kinematic range Q{sup 2}>223 GeV{sup 2} and 0.03charm fractions in the selected CC candidate event samples are extracted using the muon charge asymmetry. Muons originating from charmed hadron decays in CC events at HERA always have the same charge as the beam lepton. The extracted charm fractions in the selected CC candidate event samples are F{sub c}=9.5{+-}8.9{+-}3.0 % for e{sup +}p and F{sub c}=4.4{+-}6.9{+-}2.6 % for e{sup -}p. Due to the large statistical errors of the measured charm fractions, the strange quark density in the proton has not been extracted. (orig.)

Study of heavy-flavored particles

International Nuclear Information System (INIS)

1991-01-01

This report discusses the following topics: continuum production and decay of Λ c + charmed baryon; search for new decay modes and new charmed baryons; baryons from B meson decay; measurement of bar B 0 → D* + π - branching ratio; determination of α s ; software implementation for CLEO II physics; the measurement of the magnetic moments of baryons at the Tevatron; research and development toward a 50 picosecond TOF system; time-flight-of device Monte Carlo; continuum production of Λ c + , Σ c + , new and old decay modes; Ξ c 0 and Ξ c + production; search for B → Ξ c X; search for excited states Ξ* c 0 , Ξ* c + , Ξ c 0 ', and Ξ c + '; search for Ω c 0 ; B decays to baryons X; exclusive B → Λ c + bar p(nπ) states; B reconstruction and studies with tagged sample; determination of α s future work; and software implementation for CLEO II data analysis

Precise charm-quark mass from deep-inelastic scattering

International Nuclear Information System (INIS)

Alekhin, S.; Bluemlein, J.; Daum, K.; Lipka, K.; Moch, S.; Hamburg Univ.

2012-12-01

We present a determination of the charm-quark mass in the MS scheme using the data combination of charm production cross section measurements in deep-inelastic scattering at HERA. The framework of global analyses of the proton structure accounts for all correlations of the charm-quark mass with the other non-perturbative parameters, most importantly the gluon distribution function in the proton and the strong coupling constant α s (M Z ). We obtain at next-to-leading order in QCD the value m c (m c ) = 1.15 ± 0.04 (exp) +0.04 -0.00 (scale) GeV and at approximate next-to-next-to-leading order m c (m c ) = 1.24 ± 0.03 (exp) +0.03 -0.02 (scale) +0.00 -0.07 (theory) GeV with an accuracy competitive with other methods.

Search for diquark clustering in baryons

International Nuclear Information System (INIS)

Fleck, S.; Silvestre-Brac, B.; Richard, J.M.

1988-03-01

In the framework of the non-relativistic quark model, we examine to which extent baryons consist of a quark bound to a localized cluster of two quarks simulating a diquark. We consider ground states and orbital excitations for various flavour combinations. A striking clustering shows up sometimes especially for the leading Regge trajectory of the nucleon and single flavoured baryons or for the ground state of baryons bearing two heavy flavours. This is, however, far from being a general pattern and there are clear differences between the three-quark description of baryons and the quark-diquark model

JINR studies for a Tau-Charm Factory

International Nuclear Information System (INIS)

Chelkov, G.

1994-01-01

This paper touches on work being done a JINR relevant to a proposal for construction of a tau charm factory, and its attendant detector system. A workshop on such a device was held at JINR in 1992, and here the author touches on questions of what one wants to learn about tau particles from such a machine, the charge to the group looking at a detector design for such a facility, the general conclusions of the JINR study, and a status report of work on the JINR Tau Charm Factory project

Baryons in the heavy quark effective theory

International Nuclear Information System (INIS)

Mannel, T.; Roberts, W.; Ryzak, Z.

1990-08-01

We show how to incorporate baryons in the heavy quark effective theory. A convenient formalism is exhibited and applied to semileptonic weak decays of heavy baryons and to exclusive production of heavy baryons in e + e - annihilation. (orig.)

B/B-bar flavour tagging and doubly charmed B decays in ALEPH

International Nuclear Information System (INIS)

Barate, R.

1999-01-01

This contribution concerns three contributed papers that share the common feature of analysing fully- (or almost fully-) reconstructed B decays coming from a sample of four million hadronic Z decays collected with the ALEPH detector at LEP. In the first paper, 404 charged and neutral B mesons decaying in standard modes are fully reconstructed and used to look for resonant structure in the Bπ ± system. In the framework of Heavy Quark Symmetry (HQS), the mass of the B 2 * state and the relative production rate of the B ** system are measured. In the same sample of B mesons, significant Bπ ± charge-flavour correlations are observed. In the second paper, a search for doubly-charmed B decays with both charmed mesons reconstructed is performed. A clear signal is observed in the channels b → D S D-bar(X) and b → DD-bar(X) providing the first direct evidence for doubly-charmed b decays involving no D S production. Evidence for associated K S 0 and K ± production in the decays B → DD-bar(X) is also presented and some candidates for completely reconstructed B meson decays B → D S D-bar(nπ), B → DD-bar K S 0 and B → DD-bar K ± are observed. Furthermore, candidates for the two-body Cabibbo suppressed decays B 0 → D *- D *+ and B - → D (*)0 D (*)- are also observed. One B S 0 → D S + D S - event is reconstructed, which can be only the short-lived CP even eigenstate. In the third paper, the B S decay to D S (*)+ D S (*)- (X) is observed, tagging the final state with two φ in the same hemisphere. It corresponds mostly to the short-lived CP even eigenstate. A preliminary value of the B S short lifetime is obtained. (author)

Radiative decays of single heavy flavour baryons

International Nuclear Information System (INIS)

Majethiya, Ajay; Patel, Bhavin; Vinodkumar, P.C.

2009-01-01

The electromagnetic transitions between (J P =(3)/(2) + ) and (J P =(1)/(2) + ) baryons are important decay modes to observe new hadronic states experimentally. For the estimation of these transitions widths, we employ a non-relativistic quark potential model description with color Coulomb plus linear confinement potential. Such a description has been employed to compute the ground-state masses and magnetic moments of the single heavy flavor baryons. The magnetic moments of the baryons are obtained using the spin-flavor structure of the constituting quark composition of the baryon. Here, we also define an effective constituent mass of the quarks (ecqm) by taking into account the binding effects of the quarks within the baryon. The radiative transition widths are computed in terms of the magnetic moments of the baryon and the photon energy. Our results are compared with other theoretical models. (orig.)

Baryonic spectroscopy and its immediate future

International Nuclear Information System (INIS)

Dalitz, R.H.

1975-01-01

The quark model is reviewed briefly for baryons and the various versions of SU(6) symmetry which were proposed and used in connection with baryon spectroscopy are reviewed. A series of basic questions are reviewed which experimental work in this field should aim to settle, as a minimal program. One also heralds the beginning of a new baryon spectroscopy associated with psi physics

Multiquark resonant states

International Nuclear Information System (INIS)

Shahbazian, B.A.

1982-01-01

The invariant mass spectra of forty nine hadronic systems with hypercharge, strangeness and baryon number, varied in wide limits have been studied. Resonance peaks have been found in the invariant mass spectra of Y 2 and #betta#pπ 2495 MeV/c 2 resonant states. Three more candidates for anti qq 4 states were found #bettaπ# + π + : 1705, 2072, 2605 MeV/c 2 . The masses of all these candidates are in good agreement with Bag Model predictions. A hypercharge selection rule is suggested: ''The hypercharge of hadronic resonances in weak gravitational fields cannot exceed one Y <= 1

Results on charm hadroproduction from CERN experiment WA82

Energy Technology Data Exchange (ETDEWEB)

Antinori, F.; Barberis, D.; Beusch, W.; Davenport, M.; Dufey, J.P.; French, B.R.; Harrison, K.; Jacholkowski, A.; Kirk, A.; Lamanna, E.; Lassalle, J.C.; Muller, F.; Redaelli, N.; Roda, C.; Weymann, M. (CERN, Geneva (Switzerland)); Forino, A.; Gessaroli, R.; Mazzanti, P.; Quareni, A.; Viaggi, F. (Dipartimento di Fisica and INFN, Bologna (Italy)); Anselmi, R.; Casanova, V.; Dameri, M.; Hurst, R.; Novelli, P.; Osculati, B.; Rossi, L.; Tomasini, G. (Dipartimento di Fisica and INFN, Genova (Italy)); Buys, A.; Grard, F.; Legros, P. (Universite de Mons-Hainaut and IISN, Mons (Belgium)); Adamovich, M.; Alexandrov, Y.; Kharlamov, S.; Nechaeva, P.; Zavertyaev, M. (Lebedev Physical Institute, Moscow (Russian Federation))

1992-02-01

Experiment WA82 has collected data from 1987 to 1989 with the [Omega][prime] spectrometer at the CERN SPS. The aim of WA82 was a high statistics study of charm hadroproduction, using a silicon microstrip vertex detector and an impact parameter trigger. Latest results on the nuclear dependence of charm production and on the [ital x][sub [ital F

Are baryonic galactic halos possible

International Nuclear Information System (INIS)

Olive, K.A.; Hegyi, D.J.

1986-01-01

There is little doubt from the rotation curves of spiral galaxies that galactic halos must contain large amounts of dark matter. In this contribution, the authors review arguments which indicate that it is very unlikely that galactic halos contain substantial amounts of baryonic matter. While the authors would like to be able to present a single argument which would rule out baryonic matter, at the present time they are only able to present a collection of arguments each of which argues against one form of baryonic matter. These include: 1) snowballs; 2) gas; 3) low mass stars and Jupiters; 4) high mass stars; and 5) high metalicity objects such as rooks or dust. Black holes, which do not have a well defined baryon number, are also a possible candidate for halo matter. They briefly discuss black holes

Hadronic resonances at FAIR energies

International Nuclear Information System (INIS)

Vogel, Sascha

2013-01-01

These proceedings cover the analysis of hadronic resonances in heavy ion collisions. The model used for these studies is the Ultra-relativistic Quantum Molecular Dynamics (UrQMD) model. The model will be briefly explained, resonance observables will be highlighted and various kinematical issues will be investigated. Special emphasis will be put on the FAIR energy regime, especially highlighting the Compressed Baryonic Matter (CBM) program.

Charm CPV and rare decays at LHCb

CERN Document Server

Morello, Michael Joseph

2016-01-01

Charm physics has been playing all along a role in particle physics, by contributing to the for-mulation of the Standard Model (SM) as it is known nowadays. The level of attention on it has tremendously increased in recent years because of the first experimental observations of the slow mixing rate of the $D^0 − \\overline{D}^0$ flavour oscillations, providing definitely a full range of probes, entirely complementary to the $B$ and $K$ mesons, for mixing and $CP$- violation. In fact the charm quark is the only up-type quark that manifests flavour oscillations. Only in recent years it has been possible to collect huge and very clean samples of $D$ meson decays, several orders of magnitude larger in size than in the past, allowing also for the first time approaching the small SM expectations for $CP$-violation below the $10^{−3}$ level. Thus, the dynamics of the charm quark can be probed for the presence of New Physics with negligible SM “background”, since any generic non-SM contribu-tion would naturall...

From symmetry violation to dynamics: The charm window

International Nuclear Information System (INIS)

Appel, J.A.

1997-12-01

C.S. Wu observed parity violation in the low energy process of nuclear decay. She was the first to observe this symmetry violation at any energy. Yet, her work taught us about the form and strengths of the couplings of the massive weak boson. Today, we use the same approach. We look for very much higher mass-scale interactions through symmetry violations in the decays of charm quark systems. These charm decays provide a unique window to new physics

Doubly charmed exotic mesons: A gift of nature?

Energy Technology Data Exchange (ETDEWEB)

Carames, T.F. [Departamento de Fisica Fundamental, Universidad de Salamanca, E-37008 Salamanca (Spain); Valcarce, A., E-mail: valcarce@usal.e [Departamento de Fisica Fundamental, Universidad de Salamanca, E-37008 Salamanca (Spain); Vijande, J. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Valencia (UV) and IFIC (UV-CSIC), Valencia (Spain)

2011-05-16

We study doubly charmed exotic states by solving the scattering problem of two D mesons. Our results point to the existence of a stable isoscalar doubly charmed meson with quantum numbers (I)J{sup P}=(0)1{sup +}. We perform a thorough comparison to the results obtained within the hyperspherical harmonic formalism. Such exotic states could be measured at LHC and RHIC. Their experimental observation would, for the first time, confirm the contribution of multiquark structures to hadron spectroscopy.

Random walk of the baryon number

International Nuclear Information System (INIS)

Kazaryan, A.M.; Khlebnikov, S.Y.; Shaposhnikov, M.E.

1989-01-01

A new approach is suggested for the anomalous nonconservation of baryon number in the electroweak theory at high temperatures. Arguments are presented in support of the idea that the baryon-number changing reactions may be viewed as random Markov processes. Making use of the general theory of Markov processes, the Fokker--Planck equation for the baryon-number distribution density is obtained and kinetic coefficients are calculated

Lifetimes of heavy flavour particles

International Nuclear Information System (INIS)

Forty, R.

1994-01-01

The lifetimes of heavy-flavour hadrons are reviewed. After a brief discussion of the theoretical predictions, the problem of averaging lifetime measurements is discussed. The various experimental measurements are then presented and suitable averages performed. Charmed meson lifetimes are now measured to the few percent level, better that theory can predict, whilst for charmed baryons the lifetime hierarchy has been established for the first time. For beauty hadrons the lifetimes are measured at the 6-10 % level, and are in reasonable agreement with theoretical expectations. Beauty baryon studies ar just beginning. (author)

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 A_3/2 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.

IC at IC: IceCube can constrain the intrinsic charm of the proton

Energy Technology Data Exchange (ETDEWEB)

Laha, Ranjan; /KIPAC, Menlo Park /Stanford U., Phys. Dept. /SLAC; Brodsky, Stanley J.; /SLAC

2016-08-09

The discovery of extraterrestrial neutrinos in the 30 TeV { PeV energy range by IceCube provides new constraints on high energy astrophysics. An important background to the signal are the prompt neutrinos which originate from the decay of charm hadrons produced by high energy cosmic- ray particles interacting in the Earth's atmosphere. It is conventional to use pQCD calculations of charm hadroproduction based on gluon splitting g ! c c alone. However, QCD predicts an additional \\intrinsic" component of the heavy quark distribution which arises from diagrams where heavy quarks are multiply connected to the proton's valence quarks. We estimate the prompt neutrino spectrum due to intrinsic charm. We nd that the atmospheric prompt neutrino ux from intrinsic charm is comparable to the pQCD contribution once we normalize the intrinsic charm di erential cross sections to the ISR and the LEBC-MPS collaboration data. In future, IceCube will constrain the intrinsic charm content of the proton and will contribute to one of the major uncertainties in high energy physics phenomenology.

Achieving maximum baryon densities

International Nuclear Information System (INIS)

Gyulassy, M.

1984-01-01

In continuing work on nuclear stopping power in the energy range E/sub lab/ approx. 10 GeV/nucleon, calculations were made of the energy and baryon densities that could be achieved in uranium-uranium collisions. Results are shown. The energy density reached could exceed 2 GeV/fm 3 and baryon densities could reach as high as ten times normal nuclear densities

Weak Decays of Charmed Particles

Energy Technology Data Exchange (ETDEWEB)

Turcotte, Marc Gilles [McGill Univ., Montreal, QC (Canada)

1986-05-01

The lifetimes of charmed particles produced in interactions of high energy neutrinos with nucleons have been measured using a combination of a very high resolution emulsion-based vertex detector and a spectrometer allowing full kinematical reconstruction of the decays.

Exploring open-charm decay mode Λ_c anti Λ_c of charmonium-like state Y(4630)

International Nuclear Information System (INIS)

Liu, Xuewen; Li, Xue-Qian; Ke, Hong-Wei; Liu, Xiang

2016-01-01

The newly observed X, Y, Z exotic states are definitely not in the standard Q anti Q"' structures, thus their existence composes a challenge to our understanding on the fundamental principles of hadron physics. Therefore the studies on their decay patterns which are determined by the non-perturbative QCD will definitely shed light on the concerned physics. Generally the four-quark states might be in a molecular state or tetraquark or their mixture. In this work, we adopt the suggestion that Y(4630) is a charmonium-like tetraquark made of a diquark and an anti-diquark. If it is true, its favorable decay mode should be Y(4630) decaying into an open-charm baryon pair, since such a transition occurs via strong interaction and is super-OZI-allowed. In this work, we calculate the decay width of Y(4630) → Λ_c anti Λ_c in the framework of the quark pair creation model. Our numerical results on the partial width computed in the tetraquark configuration coincide with the Belle data within a certain error tolerance. (orig.)

Baryon destruction by asymmetric dark matter

International Nuclear Information System (INIS)

Davoudiasl, Hooman; Morrissey, David E.; Tulin, Sean; Sigurdson, Kris

2011-01-01

We investigate new and unusual signals that arise in theories where dark matter is asymmetric and carries a net antibaryon number, as may occur when the dark matter abundance is linked to the baryon abundance. Antibaryonic dark matter can cause induced nucleon decay by annihilating visible baryons through inelastic scattering. These processes lead to an effective nucleon lifetime of 10 29 -10 32 yrs in terrestrial nucleon decay experiments, if baryon number transfer between visible and dark sectors arises through new physics at the weak scale. The possibility of induced nucleon decay motivates a novel approach for direct detection of cosmic dark matter in nucleon decay experiments. Monojet searches (and related signatures) at hadron colliders also provide a complementary probe of weak-scale dark-matter-induced baryon number violation. Finally, we discuss the effects of baryon-destroying dark matter on stellar systems and show that it can be consistent with existing observations.

Baryon superfluids in AdS/CFT with flavor

Energy Technology Data Exchange (ETDEWEB)

Hoyos, Carlos [Department of Physics, Universidad de Oviedo,Avda. Calvo Sotelo 18, ES-33007 Oviedo (Spain); Itsios, Georgios [Department of Physics, Universidad de Oviedo,Avda. Calvo Sotelo 18, ES-33007 Oviedo (Spain); Instituto de Física Teórica, UNESP-Universidade Estadual Paulista,R. Dr. Bento T. Ferraz 271, Bl. II, Sao Paulo 01140-070, SP (Brazil); Vasilakis, Orestis [Department of Physics, Universidad de Oviedo,Avda. Calvo Sotelo 18, ES-33007 Oviedo (Spain)

2017-01-31

Baryonic matter is notoriously difficult to deal with in the large-N limit, as baryons become operators of very large dimension with N fields in the fundamental representation. This issue is also present in gauge/gravity duals as baryons are described by very heavy localized objects. There are however alternative large-N extrapolations of QCD where small baryonic operators exist and can be treated on an equal footing to mesons. We explore the possibility of turning on a finite density of “light” baryons in a theory with a hadronic mass gap using a gauge/gravity construction based on the D3/D7 intersection. We find a novel phase with spontaneous breaking of baryon symmetry at zero temperature.

Results on charm hadroproduction from CERN experiment WA82

International Nuclear Information System (INIS)

Antinori, F.; Barberis, D.; Beusch, W.; Davenport, M.; Dufey, J.P.; French, B.R.; Harrison, K.; Jacholkowski, A.; Kirk, A.; Lamanna, E.; Lassalle, J.C.; Muller, F.; Redaelli, N.; Roda, C.; Weymann, M.; Forino, A.; Gessaroli, R.; Mazzanti, P.; Quareni, A.; Viaggi, F.; Anselmi, R.; Casanova, V.; Dameri, M.; Hurst, R.; Novelli, P.; Osculati, B.; Rossi, L.; Tomasini, G.; Buys, A.; Grard, F.; Legros, P.; Adamovich, M.; Alexandrov, Y.; Kharlamov, S.; Nechaeva, P.; Zavertyaev, M.

1992-01-01

Experiment WA82 has collected data from 1987 to 1989 with the Ω' spectrometer at the CERN SPS. The aim of WA82 was a high statistics study of charm hadroproduction, using a silicon microstrip vertex detector and an impact parameter trigger. Latest results on the nuclear dependence of charm production and on the x F distributions of D + and D - mesons are presented and discussed

Measurement of charm and beauty photoproduction at HERA using Dμ correlations

Science.gov (United States)

H1 Collaboration; Aktas, A.; Andreev, V.; Anthonis, T.; Aplin, S.; Asmone, A.; Astvatsatourov, A.; Babaev, A.; Backovic, S.; Bähr, J.; Baghdasaryan, A.; Baranov, P.; Barrelet, E.; Bartel, W.; Baudrand, S.; Baumgartner, S.; Becker, J.; Beckingham, M.; Behnke, O.; Behrendt, O.; Belousov, A.; Berger, Ch.; Berger, N.; Bizot, J. C.; Boenig, M.-O.; Boudry, V.; Bracinik, J.; Brandt, G.; Brisson, V.; Brown, D. P.; Bruncko, D.; Büsser, F. W.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A. J.; Caron, S.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Contreras, J. G.; Coughlan, J. A.; Cox, B. E.; Cozzika, G.; Cvach, J.; Dainton, J. B.; Dau, W. D.; Daum, K.; Delcourt, B.; Demirchyan, R.; de Roeck, A.; Desch, K.; de Wolf, E. A.; Diaconu, C.; Dodonov, V.; Dubak, A.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eichler, R.; Eisele, F.; Ellerbrock, M.; Elsen, E.; Erdmann, W.; Essenov, S.; Falkewicz, A.; Faulkner, P. J. W.; Favart, L.; Fedotov, A.; Felst, R.; Ferencei, J.; Finke, L.; Fleischer, M.; Fleischmann, P.; Fleming, Y. H.; Flucke, G.; Fomenko, A.; Foresti, I.; Formánek, J.; Franke, G.; Frising, G.; Frisson, T.; Gabathuler, E.; Garutti, E.; Gayler, J.; Gerhards, R.; Gerlich, C.; Ghazaryan, S.; Ginzburgskaya, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Goettlich, M.; Gogitidze, N.; Gorbounov, S.; Goyon, C.; Grab, C.; Greenshaw, T.; Gregori, M.; Grindhammer, G.; Gwilliam, C.; Haidt, D.; Hajduk, L.; Haller, J.; Hansson, M.; Heinzelmann, G.; Henderson, R. C. W.; Henschel, H.; Henshaw, O.; Herrera, G.; Hildebrandt, M.; Hiller, K. H.; Hoffmann, D.; Horisberger, R.; Hovhannisyan, A.; Ibbotson, M.; Ismail, M.; Jacquet, M.; Janauschek, L.; Janssen, X.; Jemanov, V.; Jönsson, L.; Johnson, D. P.; Jung, H.; Kapichine, M.; Karlsson, M.; Katzy, J.; Keller, N.; Kenyon, I. R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Klimkovich, T.; Kluge, T.; Knies, G.; Knutsson, A.; Korbel, V.; Kostka, P.; Koutouev, R.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Krüger, K.; Kückens, J.; Landon, M. P. J.; Lange, W.; Laštovička, T.; Laycock, P.; Lebedev, A.; Leißner, B.; Lendermann, V.; Levonian, S.; Lindfeld, L.; Lipka, K.; List, B.; Lobodzinska, E.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lucaci-Timoce, A.-I.; Lueders, H.; Lüke, D.; Lux, T.; Lytkin, L.; Makankine, A.; Malden, N.; Malinovski, E.; Mangano, S.; Marage, P.; Marshall, R.; Martisikova, M.; Martyn, H.-U.; Maxfield, S. J.; Meer, D.; Mehta, A.; Meier, K.; Meyer, A. B.; Meyer, H.; Meyer, J.; Mikocki, S.; Milcewicz-Mika, I.; Milstead, D.; Mohamed, A.; Moreau, F.; Morozov, A.; Morris, J. V.; Mozer, M. U.; Müller, K.; Murín, P.; Nankov, K.; Naroska, B.; Naumann, J.; Naumann, Th.; Newman, P. R.; Niebuhr, C.; Nikiforov, A.; Nikitin, D.; Nowak, G.; Nozicka, M.; Oganezov, R.; Olivier, B.; Olsson, J. E.; Osman, S.; Ozerov, D.; Palichik, V.; Papadopoulou, T.; Pascaud, C.; Patel, G. D.; Peez, M.; Perez, E.; Perez-Astudillo, D.; Perieanu, A.; Petrukhin, A.; Pitzl, D.; Plačakytė, R.; Portheault, B.; Povh, B.; Prideaux, P.; Raicevic, N.; Reimer, P.; Rimmer, A.; Risler, C.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rurikova, Z.; Rusakov, S.; Salvaire, F.; Sankey, D. P. C.; Sauvan, E.; Schätzel, S.; Schilling, F.-P.; Schmidt, S.; Schmitt, S.; Schmitz, C.; Schoeffel, L.; Schöning, A.; Schröder, V.; Schultz-Coulon, H.-C.; Schwanenberger, C.; Sedlák, K.; Sefkow, F.; Sheviakov, I.; Shtarkov, L. N.; Sirois, Y.; Sloan, T.; Smirnov, P.; Soloviev, Y.; South, D.; Spaskov, V.; Specka, A.; Stella, B.; Stiewe, J.; Strauch, I.; Straumann, U.; Tchoulakov, V.; Thompson, G.; Thompson, P. D.; Tomasz, F.; Traynor, D.; Truöl, P.; Tsakov, I.; Tsipolitis, G.; Tsurin, I.; Turnau, J.; Tzamariudaki, E.; Urban, M.; Usik, A.; Utkin, D.; Valkár, S.; Valkárová, A.; Vallée, C.; van Mechelen, P.; van Remortel, N.; Vargas Trevino, A.; Vazdik, Y.; Veelken, C.; Vest, A.; Vinokurova, S.; Volchinski, V.; Vujicic, B.; Wacker, K.; Wagner, J.; Weber, G.; Weber, R.; Wegener, D.; Werner, C.; Werner, N.; Wessels, M.; Wessling, B.; Wigmore, C.; Winter, G.-G.; Wissing, Ch.; Wolf, R.; Wünsch, E.; Xella, S.; Yan, W.; Yeganov, V.; Žáček, J.; Zálešák, J.; Zhang, Z.; Zhelezov, A.; Zhokin, A.; Zimmermann, J.; Zohrabyan, H.; Zomer, F.

2005-08-01

A measurement of charm and beauty photoproduction at the electron proton collider HERA is presented based on the simultaneous detection of a D meson and a muon. The correlation between the D meson and the muon serves to separate the charm and beauty contributions and the analysis provides comparable sensitivity to both. The total and differential experimental cross sections are compared to LO and NLO QCD calculations. The measured charm cross section is in good agreement with QCD predictions including higher order effects while the beauty cross section is higher.

Photographic emulsion versus bubble chambers in charm and beauty searches

International Nuclear Information System (INIS)

Sacton, J.

1984-01-01

This chapter discusses the use of visual detectors in the search for charm and other flavors. The photographic emulsion and the bubble chamber techniques are compared. The main difficulties encounted in searching for charmed and beautiful hadrons are related to the short lifetimes of these particles and to their small production cross-sections, even at SPS energies. Resolution, visibility, the data analysis rate, and exposure time are considered. Most of the charmed hadrons present a large variety of decay modes of which only a fraction has been identified to date. First results from CESR indicate that the average charged particle multiplicity in the hadronic decay of beautiful hadrons is as high as 6.31 + or - 0.35; no B meson decay has yet been kinematically reconstructed. The case of hadronic charmed particle production at SPS energies is examined. The data show that 1) the bubble chamber technique (high resolution or holographic optics) is well suited to the study of charmed hadrons with lifetimes in the range 10 -13 to 10 -12 s; 2) searches for beautiful hadrons remain presently a domain for triggered emulsion experiments due to the smallness of the production cross-sections (provided the lifetime is not much shorter than 10 -14 s); and 3) for particles of lifetimes shorter than a few times 10 -14 s the emulsion technique is still without competitor

Associated photoproduction of charmed particles

International Nuclear Information System (INIS)

Scribano, Angelo

1982-01-01

Charmed meson pairs have been photoproduced coherently on an active multilayer silicon target in the energy range 80-150 GeV. D antiD and F antiF state have been identified and an estimate of the lifetimes is given

Precombination Cloud Collapse and Baryonic Dark Matter

Science.gov (United States)

Hogan, Craig J.

1993-01-01

A simple spherical model of dense baryon clouds in the hot big bang 'strongly nonlinear primordial isocurvature baryon fluctuations' is reviewed and used to describe the dependence of cloud behavior on the model parameters, baryon mass, and initial over-density. Gravitational collapse of clouds before and during recombination is considered including radiation diffusion and trapping, remnant type and mass, and effects on linear large-scale fluctuation modes. Sufficiently dense clouds collapse early into black holes with a minimum mass of approx. 1 solar mass, which behave dynamically like collisionless cold dark matter. Clouds below a critical over-density, however, delay collapse until recombination, remaining until then dynamically coupled to the radiation like ordinary diffuse baryons, and possibly producing remnants of other kinds and lower mass. The mean density in either type of baryonic remnant is unconstrained by observed element abundances. However, mixed or unmixed spatial variations in abundance may survive in the diffuse baryon and produce observable departures from standard predictions.

Beauty and charm production in fixed target experiments

International Nuclear Information System (INIS)

Kidonakis, Nikolaos; Vogt, Ramona

2004-01-01

We present calculations of NNLO threshold corrections for beauty and charm production in π - p and pp interactions at fixed-target experiments. Recent calculations for heavy quark hadroproduction have included next-to-next-to-leading-order (NNLO) soft-gluon corrections [1] to the double differential cross section from threshold resummation techniques [2]. These corrections are important for near-threshold beauty and charm production at fixed-target experiments, including HERA-B and some of the current and future heavy ion experiments

A new contribution to the nuclear modification factor of non-photonic electrons in Au + Au collisions at √sNN = 200 GeV

International Nuclear Information System (INIS)

Martinez-Garcia, G.; Gadrat, S.; Crochet, P.

2007-02-01

We investigate the effect of the so-called anomalous baryon/meson enhancement to the nuclear modification factor of non-photonic electrons in Au+Au collisions at √s NN = 200 GeV. It is demonstrated that an enhancement of the charm baryon/meson ratio, as it is observed for non-strange and strange hadrons, can be responsible for a part of the amplitude of the nuclear modification factor of non-photonic electrons. About half of the measured suppression of non-photonic electrons in the 2 - 4 GeV/c p t range can be explained by a charm baryon/meson enhancement of 5. This contribution to the non-photonic electron nuclear modification factor has nothing to do with heavy quark energy loss. (authors)