Hadronic light-by-light scattering contribution to the muon g-2
International Nuclear Information System (INIS)
Nyffeler, A.
2010-01-01
We review recent developments concerning the hadronic light-by-light scattering contribution to the anomalous magnetic moment of the muon. We first discuss why fully off-shell hadronic form factors should be used for the evaluation of this contribution to the g-2. We then reevaluate the numerically dominant pion-exchange contribution in the framework of large-N C QCD, using an off-shell pion-photon-photon form factor which fulfills all QCD short-distance constraints,in particular, a new short-distance constraint on the off-shell form factor at the external vertex in g-2, which relates the form factor to the quark condensate magnetic susceptibility in QCD. Combined with available evaluations of the other contributions to hadronic light-by-light scattering this leads to the new result α μ LbyL;had =(116 ± 40) x 10 -11 , with a conservative error estimate in view of the many still unsolved problems. Some potential ways for further improvements are briefly discussed as well. For the electron we obtain the new estimate α e LbyL;had =(3.9 ± 1.3) x 10 -14 . (author)
Chiral symmetry and dispersion relations: from $\\pi \\pi$ scattering to hadronic light-by-light.
CERN. Geneva
2018-01-01
Chiral symmetry provides strong constraints on hadronic matrix elements at low energy, which are most efficiently derived with chiral perturbation theory. As an effective quantum field theory the latter also accounts for rescattering or unitarity effects, albeit only perturbatively, via the loop expansion. In cases where rescattering effects are important it becomes necessary to go beyond the perturbative expansion, e.g. by using dispersion relations. A matching between the chiral and the dispersive representation provides in several cases results of high precision. I will discuss this approach with the help of a few examples, like $\\pi \\pi$ scattering (which has been tested successfully by CERN experiments like NA48/2 and DIRAC), $\\eta \\to 3 \\pi$ and the hadronic light-by-light contribution to $(g-2)_\\mu$. For the latter quantity the implementation of the dispersive approach has opened up the way to a model-independent calculation and the concrete possibility to significantly reduce the theoretical uncertain...
Towards a data-driven analysis of hadronic light-by-light scattering
Colangelo, Gilberto; Hoferichter, Martin; Kubis, Bastian; Procura, Massimiliano; Stoffer, Peter
2014-11-01
The hadronic light-by-light contribution to the anomalous magnetic moment of the muon was recently analyzed in the framework of dispersion theory, providing a systematic formalism where all input quantities are expressed in terms of on-shell form factors and scattering amplitudes that are in principle accessible in experiment. We briefly review the main ideas behind this framework and discuss the various experimental ingredients needed for the evaluation of one- and two-pion intermediate states. In particular, we identify processes that in the absence of data for doubly-virtual pion-photon interactions can help constrain parameters in the dispersive reconstruction of the relevant input quantities, the pion transition form factor and the helicity partial waves for γ*γ* → ππ.
Towards a data-driven analysis of hadronic light-by-light scattering
International Nuclear Information System (INIS)
Colangelo, Gilberto; Hoferichter, Martin; Kubis, Bastian; Procura, Massimiliano; Stoffer, Peter
2014-01-01
The hadronic light-by-light contribution to the anomalous magnetic moment of the muon was recently analyzed in the framework of dispersion theory, providing a systematic formalism where all input quantities are expressed in terms of on-shell form factors and scattering amplitudes that are in principle accessible in experiment. We briefly review the main ideas behind this framework and discuss the various experimental ingredients needed for the evaluation of one- and two-pion intermediate states. In particular, we identify processes that in the absence of data for doubly-virtual pion–photon interactions can help constrain parameters in the dispersive reconstruction of the relevant input quantities, the pion transition form factor and the helicity partial waves for γ * γ * →ππ
Towards a data-driven analysis of hadronic light-by-light scattering
Energy Technology Data Exchange (ETDEWEB)
Colangelo, Gilberto; Hoferichter, Martin [Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, Universität Bern, Sidlerstrasse 5, CH-3012 Bern (Switzerland); Kubis, Bastian [Helmholtz-Institut für Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics, Universität Bonn, D-53115 Bonn (Germany); Procura, Massimiliano; Stoffer, Peter [Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, Universität Bern, Sidlerstrasse 5, CH-3012 Bern (Switzerland)
2014-11-10
The hadronic light-by-light contribution to the anomalous magnetic moment of the muon was recently analyzed in the framework of dispersion theory, providing a systematic formalism where all input quantities are expressed in terms of on-shell form factors and scattering amplitudes that are in principle accessible in experiment. We briefly review the main ideas behind this framework and discuss the various experimental ingredients needed for the evaluation of one- and two-pion intermediate states. In particular, we identify processes that in the absence of data for doubly-virtual pion–photon interactions can help constrain parameters in the dispersive reconstruction of the relevant input quantities, the pion transition form factor and the helicity partial waves for γ{sup *}γ{sup *}→ππ.
Hadronic light-by-light scattering contribution to the muon g - 2 on the lattice
Asmussen, Nils; Gérardin, Antoine; Green, Jeremy; Gryniuk, Oleksii; von Hippel, Georg; Meyer, Harvey B.; Nyffeler, Andreas; Pascalutsa, Vladimir; Wittig, Hartmut
2018-05-01
We briefly review several activities at Mainz related to hadronic light-by-light scattering (HLbL) using lattice QCD. First we present a position-space approach to the HLbL contribution in the muon g̅2, where we focus on exploratory studies of the pion-pole contribution in a simple model and the lepton loop in QED in the continuum and in infinite volume. The second part describes a lattice calculation of the double-virtual pion transition form factor Fπ0γ*γ* (q21; q21) in the spacelike region with photon virtualities up to 1.5 GeV2 which paves the way for a lattice calculation of the pion-pole contribution to HLbL. The third topic involves HLbL forward scattering amplitudes calculated in lattice QCD which can be described, using dispersion relations (HLbL sum rules), by γ*γ* → hadrons fusion cross sections and then compared with phenomenological models.
Hadronic light-by-light scattering and the muon g −2
International Nuclear Information System (INIS)
Stoffer, P.; Colangelo, G.; Hoferichter, M.; Procura, M.
2015-01-01
The largest uncertainties in the Standard Model calculation of the anomalous magnetic moment of the muon (g − 2) μ come from hadronic contributions. In particular, it can be expected that in a few years the sub leading hadronic light-by-light (HLbL) contribution will dominate the theory uncertainty. We present a dispersive description of the HLbL tensor, which is based on unitarity, analyticity, crossing symmetry, and gauge invariance. Such a model-independent approach opens up an avenue towards a data-driven determination of the HLbL contribution to the (g − 2) μ .
Dispersion relation for hadronic light-by-light scattering: two-pion contributions
Energy Technology Data Exchange (ETDEWEB)
Colangelo, Gilberto [Albert Einstein Center for Fundamental Physics, Institute for Theoretical Physics, University of Bern, Sidlerstrasse 5, 3012 Bern (Switzerland); Hoferichter, Martin [Institute for Nuclear Theory, University of Washington, Seattle, WA 98195-1550 (United States); Kavli Institute for Theoretical Physics, University of California,Santa Barbara, CA 93106 (United States); Procura, Massimiliano [Theoretical Physics Department, CERN, Geneva (Switzerland); Stoffer, Peter [Helmholtz-Institut für Strahlen- und Kernphysik (Theory)and Bethe Center for Theoretical Physics, University of Bonn, 53115 Bonn (Germany); Department of Physics, University of California at San Diego, La Jolla, CA 92093 (United States)
2017-04-27
In this third paper of a series dedicated to a dispersive treatment of the hadronic light-by-light (HLbL) tensor, we derive a partial-wave formulation for two-pion intermediate states in the HLbL contribution to the anomalous magnetic moment of the muon (g−2){sub μ}, including a detailed discussion of the unitarity relation for arbitrary partial waves. We show that obtaining a final expression free from unphysical helicity partial waves is a subtle issue, which we thoroughly clarify. As a by-product, we obtain a set of sum rules that could be used to constrain future calculations of γ{sup ∗}γ{sup ∗}→ππ. We validate the formalism extensively using the pion-box contribution, defined by two-pion intermediate states with a pion-pole left-hand cut, and demonstrate how the full known result is reproduced when resumming the partial waves. Using dispersive fits to high-statistics data for the pion vector form factor, we provide an evaluation of the full pion box, a{sub μ}{sup π-box}=−15.9(2)×10{sup −11}. As an application of the partial-wave formalism, we present a first calculation of ππ-rescattering effects in HLbL scattering, with γ{sup ∗}γ{sup ∗}→ππ helicity partial waves constructed dispersively using ππ phase shifts derived from the inverse-amplitude method. In this way, the isospin-0 part of our calculation can be interpreted as the contribution of the f{sub 0}(500) to HLbL scattering in (g−2){sub μ}. We argue that the contribution due to charged-pion rescattering implements corrections related to the corresponding pion polarizability and show that these are moderate. Our final result for the sum of pion-box contribution and its S-wave rescattering corrections reads a{sub μ}{sup π-box}+a{sub μ,J=0}{sup ππ,π-pole} {sup LHC}=−24(1)×10{sup −11}.
Hadronic light-by-light scattering in the muon g-2: A new short-distance constraint on pion exchange
International Nuclear Information System (INIS)
Nyffeler, Andreas
2009-01-01
Recently it was pointed out that for the evaluation of the numerically dominant pion-exchange contribution to the hadronic light-by-light scattering correction in the muon g-2, a fully off-shell pion-photon-photon form factor should be used. Following this proposal, we first derive a new short-distance constraint on the off-shell form factor which enters at the external vertex for the muon g-2 and show that it is related to the quark condensate magnetic susceptibility in QCD. We then evaluate the pion-exchange contribution in the framework of large-N C QCD using an off-shell form factor which fulfills all short-distance constraints. With a value for the magnetic susceptibility as estimated in the same large-N C framework, we obtain the result a μ LbyL;π 0 =(72±12)x10 -11 . Updating our earlier results for the contributions from the exchanges of the η and η ' using simple vector-meson dominance form factors, we obtain a μ LbyL;PS =(99±16)x10 -11 for the sum of all light pseudoscalars. Combined with available evaluations for the other contributions to hadronic light-by-light scattering this leads to the new estimate a μ LbyL;had =(116±40)x10 -11 .
Light-by-light scattering and muon's anomalous magnetic moment
International Nuclear Information System (INIS)
Pauk, Vladyslav
2014-01-01
A study of hadron production by photons opens unique ways to address a number of fundamental problems in strong interaction physics as well as fundamental questions in Quantum Field Theory. In particular, an understanding of two-photon processes is of crucial importance for constraining the hadronic uncertainties in precision measurements and in searches for new physics. The process of γ * γ * fusion (by quasi-real photons γ or virtual photons γ * ) into leptons and hadrons has been observed and studied in detail at nearly all high-energy colliders. From the theoretical point of view two-photon processes are very complicated. One of approaches which may be efficiently used to study non-perturbative features of two-photon production is based on a dispersion theory. Using general properties of relativistic quantum field theory we relate in this work the forward light-by-light scattering to energy weighted integrals of the γ * γ fusion cross sections. The first type of new relations derived in this work have the form of exact super-convergence sum rules. The second type involves the effective constants of the low-energy photon-photon interaction and allow to define them in terms of two-photon production cross sections. We subsequently test and verify these sum rules exactly at tree and one-loop level in scalar and spinor QED. Furthermore, we test the criterium of the tree-level unitarity imposed by the sum rules on the example of the massive spin-1 QED. Next, we apply the sum rules for the forward light-by-light scattering process within the context of the φ 4 quantum field theory. Within this theory, we present a stringent causality criterion and apply it to a particular non-perturbative resummation of graphs. Applied to the γ * γ production of mesons, the superconvergence sum rules lead to intricate relations between theγγ decay widths and the γ * γ transition form factors for (pseudo-) scalar, axial-vector and tensor mesons. We discuss the
ATLAS Event Display: Light-by-Light Scattering
ATLAS Collaboration
2017-01-01
An event display of light-by-light scattering in ultra-peripheral lead+lead collisions at 5.02 TeV with the ATLAS detector at the LHC. The event 461251458 from run 287931 recorded on 13 December 2015 at 09:51:07 is shown. Two back-to-back photons with an invariant mass of 24 GeV with no additional activity in the detector are presented. All calorimeter cells with E>500 MeV are shown.
Positron Production in Multiphoton Light-by-Light Scattering
Energy Technology Data Exchange (ETDEWEB)
Koffas, Thomas
2003-07-28
We present the results of an experimental study on e{sup +}e{sup -} pair production during the collision of a low emittance 46.6 GeV electron beam with terawatt laser pulses from a Nd:glass laser at 527 nm wavelength and with linear polarization. The experiment was conducted at the Final Focus Test Beam facility in the Stanford Linear Accelerator Center. Results with a 49.1 GeV electron beam are also included. A signal of 106 {+-} 14 positrons for the 46.6 GeV electron beam case and of 22 {+-} 10 positrons for the 49.1 GcV case above background, has been detected. We interpret the positrons as the products of a two-step process during which laser photons are backscattered to high energy gamma photons that absorb in their turn several laser photons in order to produce a e{sup +}e{sup -} pair. The data compare well with the existing theoretical models. This is the first observation in the laboratory of inelastic Light-by-Light scattering with only real photons. Alternatively, the data are interpreted as a manifestation of the spontaneous breakdown of the vacuum under the influence of an intense external alternating electric field.
On the Hadronic light-by-light contribution to the muon g - 2
Bijnens, Johan
2018-05-01
This talk is about the hadronic light-by-light contribution to the muon anomalous magnetic moment, mainly our old work but including some newer results as well. It concentrates on the model calculations. Most attention is paid to pseudo-scalar exchange and the pion loop contribution. Scalar, a1-exchange and other contributions are shortly discussed as well. For the π0-exchange a possible large cancellation between connected and disconnected diagrams is expected.
Upper Bound on the Hadronic Light-By-Light Contribution to the Muon g-2
International Nuclear Information System (INIS)
Erler, Jens; Sanchez, Genaro Toledo
2006-01-01
There are indications that hadronic loops in some electroweak observables are almost saturated by parton level effects. Taking this as the hypothesis for this work, we propose a genuine parton level estimate of the hadronic light-by-light contribution to the anomalous magnetic moment of the muon, a μ LBL (had). Our quark mass definitions and values are motivated in detail, and the simplicity of our approach allows for a transparent error estimate. For infinitely heavy quarks our treatment is exact, while for asymptotically small quark masses a μ LBL (had) is overestimated. Interpolating, this suggests quoting an upper bound. We obtain a μ LBL (had) -9 (95% C.L.)
Measuring light-by-light scattering at the LHC and FCC
d'Enterria, David
2016-01-01
Elastic light-by-light scattering, $\\gamma\\gamma\\to\\gamma\\gamma$, can be measured in electromagnetic interactions of lead (Pb) ions at the Large Hadron Collider (LHC) and Future Circular Collider (FCC), using the large (quasi)real photon fluxes available in ultraperipheral collisions. The $\\gamma\\gamma\\to\\gamma\\gamma$ cross sections for diphoton masses m$_{\\gamma\\gamma}>$ 5 GeV in pp, pPb, and PbPb collisions at LHC ($\\sqrt{\\rm s_{_{NN}}}$ = 5.5, 8.8, 14 TeV) and FCC ($\\sqrt{\\rm s_{_{NN}}}$ = 39, 63, 100 TeV) center-of-mass energies are presented. The measurement has controllable backgrounds in PbPb collisions, and one expects about 70 and 2500 signal events per year at the LHC and FCC respectively, after typical detector acceptance and reconstruction efficiency selections.
Light-by-light scattering and muon's anomalous magnetic moment
Energy Technology Data Exchange (ETDEWEB)
Pauk, Vladyslav
2014-07-01
A study of hadron production by photons opens unique ways to address a number of fundamental problems in strong interaction physics as well as fundamental questions in Quantum Field Theory. In particular, an understanding of two-photon processes is of crucial importance for constraining the hadronic uncertainties in precision measurements and in searches for new physics. The process of γ{sup *}γ{sup *} fusion (by quasi-real photons γ or virtual photons γ{sup *}) into leptons and hadrons has been observed and studied in detail at nearly all high-energy colliders. From the theoretical point of view two-photon processes are very complicated. One of approaches which may be efficiently used to study non-perturbative features of two-photon production is based on a dispersion theory. Using general properties of relativistic quantum field theory we relate in this work the forward light-by-light scattering to energy weighted integrals of the γ{sup *}γ fusion cross sections. The first type of new relations derived in this work have the form of exact super-convergence sum rules. The second type involves the effective constants of the low-energy photon-photon interaction and allow to define them in terms of two-photon production cross sections. We subsequently test and verify these sum rules exactly at tree and one-loop level in scalar and spinor QED. Furthermore, we test the criterium of the tree-level unitarity imposed by the sum rules on the example of the massive spin-1 QED. Next, we apply the sum rules for the forward light-by-light scattering process within the context of the φ{sup 4} quantum field theory. Within this theory, we present a stringent causality criterion and apply it to a particular non-perturbative resummation of graphs. Applied to the γ{sup *}γ production of mesons, the superconvergence sum rules lead to intricate relations between theγγ decay widths and the γ{sup *}γ transition form factors for (pseudo-) scalar, axial-vector and tensor
Light-by-Light Scattering Constraint on Born-Infeld Theory.
Ellis, John; Mavromatos, Nick E; You, Tevong
2017-06-30
The recent measurement by ATLAS of light-by-light scattering in LHC Pb-Pb collisions is the first direct evidence for this basic process. We find that it excludes a range of the mass scale of a nonlinear Born-Infeld extension of QED that is ≲100 GeV, a much stronger constraint than those derived previously. In the case of a Born-Infeld extension of the standard model in which the U(1)_{Y} hypercharge gauge symmetry is realized nonlinearly, the limit on the corresponding mass reach is ∼90 GeV, which, in turn, imposes a lower limit of ≳11 TeV on the magnetic monopole mass in such a U(1)_{Y} Born-Infeld theory.
Aaboud, Morad; Abbott, Brad; Abdallah, Jalal; Abdinov, Ovsat; Abeloos, Baptiste; Abidi, Syed Haider; AbouZeid, Ossama; Abraham, Nicola; Abramowicz, Halina; Abreu, Henso; Abreu, Ricardo; Abulaiti, Yiming; Acharya, Bobby Samir; Adachi, Shunsuke; Adamczyk, Leszek; Adelman, Jahred; Adersberger, Michael; Adye, Tim; Affolder, Tony; Agatonovic-Jovin, Tatjana; Agheorghiesei, Catalin; Aguilar-Saavedra, Juan Antonio; Ahlen, Steven; Ahmadov, Faig; Aielli, Giulio; Akatsuka, Shunichi; Akerstedt, Henrik; Åkesson, Torsten Paul Ake; Akimov, Andrei; Alberghi, Gian Luigi; Albert, Justin; Alconada Verzini, Maria Josefina; Aleksa, Martin; Aleksandrov, Igor; Alexa, Calin; Alexander, Gideon; Alexopoulos, Theodoros; Alhroob, Muhammad; Ali, Babar; Aliev, Malik; Alimonti, Gianluca; Alison, John; Alkire, Steven Patrick; Allbrooke, Benedict; Allen, Benjamin William; Allport, Phillip; Aloisio, Alberto; Alonso, Alejandro; Alonso, Francisco; Alpigiani, Cristiano; Alshehri, Azzah Aziz; Alstaty, Mahmoud; Alvarez Gonzalez, Barbara; Άlvarez Piqueras, Damián; Alviggi, Mariagrazia; Amadio, Brian Thomas; Amaral Coutinho, Yara; Amelung, Christoph; Amidei, Dante; Amor Dos Santos, Susana Patricia; Amorim, Antonio; Amoroso, Simone; Amundsen, Glenn; Anastopoulos, Christos; Ancu, Lucian Stefan; Andari, Nansi; Andeen, Timothy; Anders, Christoph Falk; Anders, John Kenneth; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Angelidakis, Stylianos; Angelozzi, Ivan; Angerami, Aaron; Anghinolfi, Francis; Anisenkov, Alexey; Anjos, Nuno; Annovi, Alberto; Antel, Claire; Antonelli, Mario; Antonov, Alexey; Antrim, Daniel Joseph; Anulli, Fabio; Aoki, Masato; Aperio Bella, Ludovica; Arabidze, Giorgi; Arai, Yasuo; Araque, Juan Pedro; Araujo Ferraz, Victor; Arce, Ayana; Ardell, Rose Elisabeth; Arduh, Francisco Anuar; Arguin, Jean-Francois; Argyropoulos, Spyridon; Arik, Metin; Armbruster, Aaron James; Armitage, Lewis James; Arnaez, Olivier; Arnold, Hannah; Arratia, Miguel; Arslan, Ozan; Artamonov, Andrei; Artoni, Giacomo; Artz, Sebastian; Asai, Shoji; Asbah, Nedaa; Ashkenazi, Adi; Asquith, Lily; Assamagan, Ketevi; Astalos, Robert; Atkinson, Markus; Atlay, Naim Bora; Augsten, Kamil; Avolio, Giuseppe; Axen, Bradley; Ayoub, Mohamad Kassem; Azuelos, Georges; Baas, Alessandra; Baca, Matthew John; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Backhaus, Malte; Bagiacchi, Paolo; Bagnaia, Paolo; Baines, John; Bajic, Milena; Baker, Oliver Keith; Baldin, Evgenii; Balek, Petr; Balestri, Thomas; Balli, Fabrice; Balunas, William Keaton; Banas, Elzbieta; Banerjee, Swagato; Bannoura, Arwa A E; Barak, Liron; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Barillari, Teresa; Barisits, Martin-Stefan; Barklow, Timothy; Barlow, Nick; Barnes, Sarah Louise; Barnett, Bruce; Barnett, Michael; Barnovska-Blenessy, Zuzana; Baroncelli, Antonio; Barone, Gaetano; Barr, Alan; Barranco Navarro, Laura; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Bartoldus, Rainer; Barton, Adam Edward; Bartos, Pavol; Basalaev, Artem; Bassalat, Ahmed; Bates, Richard; Batista, Santiago Juan; Batley, Richard; Battaglia, Marco; Bauce, Matteo; Bauer, Florian; Bawa, Harinder Singh; Beacham, James; Beattie, Michael David; Beau, Tristan; Beauchemin, Pierre-Hugues; Bechtle, Philip; Beck, Hans~Peter; Becker, Kathrin; Becker, Maurice; Beckingham, Matthew; Becot, Cyril; Beddall, Andrew; Beddall, Ayda; Bednyakov, Vadim; Bedognetti, Matteo; Bee, Christopher; Beermann, Thomas; Begalli, Marcia; Begel, Michael; Behr, Janna Katharina; Bell, Andrew Stuart; Bella, Gideon; Bellagamba, Lorenzo; Bellerive, Alain; Bellomo, Massimiliano; Belotskiy, Konstantin; Beltramello, Olga; Belyaev, Nikita; Benary, Odette; Benchekroun, Driss; Bender, Michael; Bendtz, Katarina; Benekos, Nektarios; Benhammou, Yan; Benhar Noccioli, Eleonora; Benitez, Jose; Benjamin, Douglas; Benoit, Mathieu; Bensinger, James; Bentvelsen, Stan; Beresford, Lydia; Beretta, Matteo; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Beringer, Jürg; Berlendis, Simon; Bernard, Nathan Rogers; Bernardi, Gregorio; Bernius, Catrin; Bernlochner, Florian Urs; Berry, Tracey; Berta, Peter; Bertella, Claudia; Bertoli, Gabriele; Bertolucci, Federico; Bertram, Iain Alexander; Bertsche, Carolyn; Bertsche, David; Besjes, Geert-Jan; Bessidskaia Bylund, Olga; Bessner, Martin Florian; Besson, Nathalie; Betancourt, Christopher; Bethani, Agni; Bethke, Siegfried; Bevan, Adrian John; Bianchi, Riccardo-Maria; Bianco, Michele; Biebel, Otmar; Biedermann, Dustin; Bielski, Rafal; Biesuz, Nicolo Vladi; Biglietti, Michela; Bilbao De Mendizabal, Javier; Billoud, Thomas Remy Victor; Bilokon, Halina; Bindi, Marcello; Bingul, Ahmet; Bini, Cesare; Biondi, Silvia; Bisanz, Tobias; Bittrich, Carsten; Bjergaard, David Martin; Black, Curtis; Black, James; Black, Kevin; Blackburn, Daniel; Blair, Robert; Blazek, Tomas; Bloch, Ingo; Blocker, Craig; Blue, Andrew; Blum, Walter; Blumenschein, Ulrike; Blunier, Sylvain; Bobbink, Gerjan; Bobrovnikov, Victor; Bocchetta, Simona Serena; Bocci, Andrea; Bock, Christopher; Boehler, Michael; Boerner, Daniela; Bogavac, Danijela; Bogdanchikov, Alexander; Bohm, Christian; Boisvert, Veronique; Bokan, Petar; Bold, Tomasz; Boldyrev, Alexey; Bomben, Marco; Bona, Marcella; Boonekamp, Maarten; Borisov, Anatoly; Borissov, Guennadi; Bortfeldt, Jonathan; Bortoletto, Daniela; Bortolotto, Valerio; Bos, Kors; Boscherini, Davide; Bosman, Martine; Bossio Sola, Jonathan David; Boudreau, Joseph; Bouffard, Julian; Bouhova-Thacker, Evelina Vassileva; Boumediene, Djamel Eddine; Bourdarios, Claire; Boutle, Sarah Kate; Boveia, Antonio; Boyd, James; Boyko, Igor; Bracinik, Juraj; Brandt, Andrew; Brandt, Gerhard; Brandt, Oleg; Bratzler, Uwe; Brau, Benjamin; Brau, James; Breaden Madden, William Dmitri; Brendlinger, Kurt; Brennan, Amelia Jean; Brenner, Lydia; Brenner, Richard; Bressler, Shikma; Briglin, Daniel Lawrence; Bristow, Timothy Michael; Britton, Dave; Britzger, Daniel; Brochu, Frederic; Brock, Ian; Brock, Raymond; Brooijmans, Gustaaf; Brooks, Timothy; Brooks, William; Brosamer, Jacquelyn; Brost, Elizabeth; Broughton, James; Bruckman de Renstrom, Pawel; Bruncko, Dusan; Bruni, Alessia; Bruni, Graziano; Bruni, Lucrezia Stella; Brunt, Benjamin; Bruschi, Marco; Bruscino, Nello; Bryant, Patrick; Bryngemark, Lene; Buanes, Trygve; Buat, Quentin; Buchholz, Peter; Buckley, Andrew; Budagov, Ioulian; Buehrer, Felix; Bugge, Magnar Kopangen; Bulekov, Oleg; Bullock, Daniel; Burckhart, Helfried; Burdin, Sergey; Burgard, Carsten Daniel; Burger, Angela Maria; Burghgrave, Blake; Burka, Klaudia; Burke, Stephen; Burmeister, Ingo; Burr, Jonathan Thomas Peter; Busato, Emmanuel; Büscher, Daniel; Büscher, Volker; Bussey, Peter; Butler, John; Buttar, Craig; Butterworth, Jonathan; Butti, Pierfrancesco; Buttinger, William; Buzatu, Adrian; Buzykaev, Aleksey; Cabrera Urbán, Susana; Caforio, Davide; Cairo, Valentina; Cakir, Orhan; Calace, Noemi; Calafiura, Paolo; Calandri, Alessandro; Calderini, Giovanni; Calfayan, Philippe; Callea, Giuseppe; Caloba, Luiz; Calvente Lopez, Sergio; Calvet, David; Calvet, Samuel; Calvet, Thomas Philippe; Camacho Toro, Reina; Camarda, Stefano; Camarri, Paolo; Cameron, David; Caminal Armadans, Roger; Camincher, Clement; Campana, Simone; Campanelli, Mario; Camplani, Alessandra; Campoverde, Angel; Canale, Vincenzo; Cano Bret, Marc; Cantero, Josu; Cao, Tingting; Capeans Garrido, Maria Del Mar; Caprini, Irinel; Caprini, Mihai; Capua, Marcella; Carbone, Ryne Michael; Cardarelli, Roberto; Cardillo, Fabio; Carli, Ina; Carli, Tancredi; Carlino, Gianpaolo; Carlson, Benjamin Taylor; Carminati, Leonardo; Carney, Rebecca; Caron, Sascha; Carquin, Edson; Carrillo-Montoya, German D; Carvalho, João; Casadei, Diego; Casado, Maria Pilar; Casolino, Mirkoantonio; Casper, David William; Castelijn, Remco; Castelli, Angelantonio; Castillo Gimenez, Victoria; Castro, Nuno Filipe; Catinaccio, Andrea; Catmore, James; Cattai, Ariella; Caudron, Julien; Cavaliere, Viviana; Cavallaro, Emanuele; Cavalli, Donatella; Cavalli-Sforza, Matteo; Cavasinni, Vincenzo; Celebi, Emre; Ceradini, Filippo; Cerda Alberich, Leonor; Santiago Cerqueira, Augusto; Cerri, Alessandro; Cerrito, Lucio; Cerutti, Fabio; Cervelli, Alberto; Cetin, Serkant Ali; Chafaq, Aziz; Chakraborty, Dhiman; Chan, Stephen Kam-wah; Chan, Wing Sheung; Chan, Yat Long; Chang, Philip; Chapman, John Derek; Charlton, Dave; Chatterjee, Avishek; Chau, Chav Chhiv; Chavez Barajas, Carlos Alberto; Che, Siinn; Cheatham, Susan; Chegwidden, Andrew; Chekanov, Sergei; Chekulaev, Sergey; Chelkov, Gueorgui; Chelstowska, Magda Anna; Chen, Chunhui; Chen, Hucheng; Chen, Shenjian; Chen, Shion; Chen, Xin; Chen, Ye; Cheng, Hok Chuen; Cheng, Huajie; Cheng, Yangyang; Cheplakov, Alexander; Cheremushkina, Evgenia; Cherkaoui El Moursli, Rajaa; Chernyatin, Valeriy; Cheu, Elliott; Chevalier, Laurent; Chiarella, Vitaliano; Chiarelli, Giorgio; Chiodini, Gabriele; Chisholm, Andrew; Chitan, Adrian; Chiu, Yu Him Justin; Chizhov, Mihail; Choi, Kyungeon; Chomont, Arthur Rene; Chouridou, Sofia; Chow, Bonnie Kar Bo; Christodoulou, Valentinos; Chromek-Burckhart, Doris; Chu, Ming Chung; Chudoba, Jiri; Chuinard, Annabelle Julia; Chwastowski, Janusz; Chytka, Ladislav; Ciftci, Abbas Kenan; Cinca, Diane; Cindro, Vladimir; Cioara, Irina Antonela; Ciocca, Claudia; Ciocio, Alessandra; Cirotto, Francesco; Citron, Zvi Hirsh; Citterio, Mauro; Ciubancan, Mihai; Clark, Allan G; Clark, Brian Lee; Clark, Michael; Clark, Philip James; Clarke, Robert; Clement, Christophe; Coadou, Yann; Cobal, Marina; Coccaro, Andrea; Cochran, James H; Colasurdo, Luca; Cole, Brian; Colijn, Auke-Pieter; Collot, Johann; Colombo, Tommaso; Conde Muiño, Patricia; Coniavitis, Elias; Connell, Simon Henry; Connelly, Ian; Consorti, Valerio; Constantinescu, Serban; Conti, Geraldine; Conventi, Francesco; Cooke, Mark; Cooper, Ben; Cooper-Sarkar, Amanda; Cormier, Felix; Cormier, Kyle James Read; Cornelissen, Thijs; Corradi, Massimo; Corriveau, Francois; Cortes-Gonzalez, Arely; Cortiana, Giorgio; Costa, Giuseppe; Costa, María José; Costanzo, Davide; Cottin, Giovanna; Cowan, Glen; Cox, Brian; Cranmer, Kyle; Crawley, Samuel Joseph; Creager, Rachael; Cree, Graham; Crépé-Renaudin, Sabine; Crescioli, Francesco; Cribbs, Wayne Allen; Crispin Ortuzar, Mireia; Cristinziani, Markus; Croft, Vince; Crosetti, Giovanni; Cueto, Ana; Cuhadar Donszelmann, Tulay; Cummings, Jane; Curatolo, Maria; Cúth, Jakub; Czirr, Hendrik; Czodrowski, Patrick; D'amen, Gabriele; D'Auria, Saverio; D'Onofrio, Monica; Da Cunha Sargedas De Sousa, Mario Jose; Da Via, Cinzia; Dabrowski, Wladyslaw; Dado, Tomas; Dai, Tiesheng; Dale, Orjan; Dallaire, Frederick; Dallapiccola, Carlo; Dam, Mogens; Dandoy, Jeffrey; Dang, Nguyen Phuong; Daniells, Andrew Christopher; Dann, Nicholas Stuart; Danninger, Matthias; Dano Hoffmann, Maria; Dao, Valerio; Darbo, Giovanni; Darmora, Smita; Dassoulas, James; Dattagupta, Aparajita; Daubney, Thomas; Davey, Will; David, Claire; Davidek, Tomas; Davies, Merlin; Davison, Peter; Dawe, Edmund; Dawson, Ian; De, Kaushik; de Asmundis, Riccardo; De Benedetti, Abraham; De Castro, Stefano; De Cecco, Sandro; De Groot, Nicolo; de Jong, Paul; De la Torre, Hector; De Lorenzi, Francesco; De Maria, Antonio; De Pedis, Daniele; De Salvo, Alessandro; De Sanctis, Umberto; De Santo, Antonella; De Vasconcelos Corga, Kevin; De Vivie De Regie, Jean-Baptiste; Dearnaley, William James; Debbe, Ramiro; Debenedetti, Chiara; Dedovich, Dmitri; Dehghanian, Nooshin; Deigaard, Ingrid; Del Gaudio, Michela; Del Peso, Jose; Del Prete, Tarcisio; Delgove, David; Deliot, Frederic; Delitzsch, Chris Malena; Dell'Acqua, Andrea; Dell'Asta, Lidia; Dell'Orso, Mauro; Della Pietra, Massimo; della Volpe, Domenico; Delmastro, Marco; Delporte, Charles; Delsart, Pierre-Antoine; DeMarco, David; Demers, Sarah; Demichev, Mikhail; Demilly, Aurelien; Denisov, Sergey; Denysiuk, Denys; Derendarz, Dominik; Derkaoui, Jamal Eddine; Derue, Frederic; Dervan, Paul; Desch, Klaus Kurt; Deterre, Cecile; Dette, Karola; Deviveiros, Pier-Olivier; Dewhurst, Alastair; Dhaliwal, Saminder; Di Ciaccio, Anna; Di Ciaccio, Lucia; Di Clemente, William Kennedy; Di Donato, Camilla; Di Girolamo, Alessandro; Di Girolamo, Beniamino; Di Micco, Biagio; Di Nardo, Roberto; Di Petrillo, Karri Folan; Di Simone, Andrea; Di Sipio, Riccardo; Di Valentino, David; Diaconu, Cristinel; Diamond, Miriam; Dias, Flavia; Diaz, Marco Aurelio; Diehl, Edward; Dietrich, Janet; Díez Cornell, Sergio; Dimitrievska, Aleksandra; Dingfelder, Jochen; Dita, Petre; Dita, Sanda; Dittus, Fridolin; Djama, Fares; Djobava, Tamar; Djuvsland, Julia Isabell; Barros do Vale, Maria Aline; Dobos, Daniel; Dobre, Monica; Doglioni, Caterina; Dolejsi, Jiri; Dolezal, Zdenek; Donadelli, Marisilvia; Donati, Simone; Dondero, Paolo; Donini, Julien; Dopke, Jens; Doria, Alessandra; Dova, Maria-Teresa; Doyle, Tony; Drechsler, Eric; Dris, Manolis; Du, Yanyan; Duarte-Campderros, Jorge; Duchovni, Ehud; Duckeck, Guenter; Ducourthial, Audrey; Ducu, Otilia Anamaria; Duda, Dominik; Dudarev, Alexey; Dudder, Andreas Christian; Duffield, Emily Marie; Duflot, Laurent; Dührssen, Michael; Dumancic, Mirta; Dumitriu, Ana Elena; Duncan, Anna Kathryn; Dunford, Monica; Duran Yildiz, Hatice; Düren, Michael; Durglishvili, Archil; Duschinger, Dirk; Dutta, Baishali; Dyndal, Mateusz; Eckardt, Christoph; Ecker, Katharina Maria; Edgar, Ryan Christopher; Eifert, Till; Eigen, Gerald; Einsweiler, Kevin; Ekelof, Tord; El Kacimi, Mohamed; El Kosseifi, Rima; Ellajosyula, Venugopal; Ellert, Mattias; Elles, Sabine; Ellinghaus, Frank; Elliot, Alison; Ellis, Nicolas; Elmsheuser, Johannes; Elsing, Markus; Emeliyanov, Dmitry; Enari, Yuji; Endner, Oliver Chris; Ennis, Joseph Stanford; Erdmann, Johannes; Ereditato, Antonio; Ernis, Gunar; Ernst, Michael; Errede, Steven; Ertel, Eugen; Escalier, Marc; Esch, Hendrik; Escobar, Carlos; Esposito, Bellisario; Etienvre, Anne-Isabelle; Etzion, Erez; Evans, Hal; Ezhilov, Alexey; Fabbri, Federica; Fabbri, Laura; Facini, Gabriel; Fakhrutdinov, Rinat; Falciano, Speranza; Falla, Rebecca Jane; Faltova, Jana; Fang, Yaquan; Fanti, Marcello; Farbin, Amir; Farilla, Addolorata; Farina, Christian; Farina, Edoardo Maria; Farooque, Trisha; Farrell, Steven; Farrington, Sinead; Farthouat, Philippe; Fassi, Farida; Fassnacht, Patrick; Fassouliotis, Dimitrios; Faucci Giannelli, Michele; Favareto, Andrea; Fawcett, William James; Fayard, Louis; Fedin, Oleg; Fedorko, Wojciech; Feigl, Simon; Feligioni, Lorenzo; Feng, Cunfeng; Feng, Eric; Feng, Haolu; Fenyuk, Alexander; Feremenga, Last; Fernandez Martinez, Patricia; Fernandez Perez, Sonia; Ferrando, James; Ferrari, Arnaud; Ferrari, Pamela; Ferrari, Roberto; Ferreira de Lima, Danilo Enoque; Ferrer, Antonio; Ferrere, Didier; Ferretti, Claudio; Fiedler, Frank; Filipčič, Andrej; Filipuzzi, Marco; Filthaut, Frank; Fincke-Keeler, Margret; Finelli, Kevin Daniel; Fiolhais, Miguel; Fiorini, Luca; Fischer, Adam; Fischer, Cora; Fischer, Julia; Fisher, Wade Cameron; Flaschel, Nils; Fleck, Ivor; Fleischmann, Philipp; Fletcher, Rob Roy MacGregor; Flick, Tobias; Flierl, Bernhard Matthias; Flores Castillo, Luis; Flowerdew, Michael; Forcolin, Giulio Tiziano; Formica, Andrea; Forti, Alessandra; Foster, Andrew Geoffrey; Fournier, Daniel; Fox, Harald; Fracchia, Silvia; Francavilla, Paolo; Franchini, Matteo; Franchino, Silvia; Francis, David; Franconi, Laura; Franklin, Melissa; Frate, Meghan; Fraternali, Marco; Freeborn, David; Fressard-Batraneanu, Silvia; Freund, Benjamin; Froidevaux, Daniel; Frost, James; Fukunaga, Chikara; Fullana Torregrosa, Esteban; Fusayasu, Takahiro; Fuster, Juan; Gabaldon, Carolina; Gabizon, Ofir; Gabrielli, Alessandro; Gabrielli, Andrea; Gach, Grzegorz; Gadatsch, Stefan; Gadomski, Szymon; Gagliardi, Guido; Gagnon, Louis Guillaume; Gagnon, Pauline; Galea, Cristina; Galhardo, Bruno; Gallas, Elizabeth; Gallop, Bruce; Gallus, Petr; Galster, Gorm Aske Gram Krohn; Gan, KK; Ganguly, Sanmay; Gao, Jun; Gao, Yanyan; Gao, Yongsheng; Garay Walls, Francisca; García, Carmen; García Navarro, José Enrique; Garcia-Sciveres, Maurice; Gardner, Robert; Garelli, Nicoletta; Garonne, Vincent; Gascon Bravo, Alberto; Gasnikova, Ksenia; Gatti, Claudio; Gaudiello, Andrea; Gaudio, Gabriella; Gavrilenko, Igor; Gay, Colin; Gaycken, Goetz; Gazis, Evangelos; Gee, Norman; Geisen, Marc; Geisler, Manuel Patrice; Gellerstedt, Karl; Gemme, Claudia; Genest, Marie-Hélène; Geng, Cong; Gentile, Simonetta; Gentsos, Christos; George, Simon; Gerbaudo, Davide; Gershon, Avi; Ghasemi, Sara; Ghneimat, Mazuza; Giacobbe, Benedetto; Giagu, Stefano; Giannetti, Paola; Gibson, Stephen; Gignac, Matthew; Gilchriese, Murdock; Gillberg, Dag; Gilles, Geoffrey; Gingrich, Douglas; Giokaris, Nikos; Giordani, MarioPaolo; Giorgi, Filippo Maria; Giraud, Pierre-Francois; Giromini, Paolo; Giugni, Danilo; Giuli, Francesco; Giuliani, Claudia; Giulini, Maddalena; Gjelsten, Børge Kile; Gkaitatzis, Stamatios; Gkialas, Ioannis; Gkougkousis, Evangelos Leonidas; Gladilin, Leonid; Glasman, Claudia; Glatzer, Julian; Glaysher, Paul; Glazov, Alexandre; Goblirsch-Kolb, Maximilian; Godlewski, Jan; Goldfarb, Steven; Golling, Tobias; Golubkov, Dmitry; Gomes, Agostinho; Gonçalo, Ricardo; Goncalves Gama, Rafael; Goncalves Pinto Firmino Da Costa, Joao; Gonella, Giulia; Gonella, Laura; Gongadze, Alexi; González de la Hoz, Santiago; Gonzalez-Sevilla, Sergio; Goossens, Luc; Gorbounov, Petr Andreevich; Gordon, Howard; Gorelov, Igor; Gorini, Benedetto; Gorini, Edoardo; Gorišek, Andrej; Goshaw, Alfred; Gössling, Claus; Gostkin, Mikhail Ivanovitch; Goudet, Christophe Raymond; Goujdami, Driss; Goussiou, Anna; Govender, Nicolin; Gozani, Eitan; Graber, Lars; Grabowska-Bold, Iwona; Gradin, Per Olov Joakim; Gramling, Johanna; Gramstad, Eirik; Grancagnolo, Sergio; Gratchev, Vadim; Gravila, Paul Mircea; Gray, Heather; Greenwood, Zeno Dixon; Grefe, Christian; Gregersen, Kristian; Gregor, Ingrid-Maria; Grenier, Philippe; Grevtsov, Kirill; Griffiths, Justin; Grillo, Alexander; Grimm, Kathryn; Grinstein, Sebastian; Gris, Philippe Luc Yves; Grivaz, Jean-Francois; Groh, Sabrina; Gross, Eilam; Grosse-Knetter, Joern; Grossi, Giulio Cornelio; Grout, Zara Jane; Guan, Liang; Guan, Wen; Guenther, Jaroslav; Guescini, Francesco; Guest, Daniel; Gueta, Orel; Gui, Bin; Guido, Elisa; Guillemin, Thibault; Guindon, Stefan; Gul, Umar; Gumpert, Christian; Guo, Jun; Guo, Wen; Guo, Yicheng; Gupta, Ruchi; Gupta, Shaun; Gustavino, Giuliano; Gutierrez, Phillip; Gutierrez Ortiz, Nicolas Gilberto; Gutschow, Christian; Guyot, Claude; Guzik, Marcin Pawel; Gwenlan, Claire; Gwilliam, Carl; Haas, Andy; Haber, Carl; Hadavand, Haleh Khani; Hadef, Asma; Hageböck, Stephan; Hagihara, Mutsuto; Hakobyan, Hrachya; Haleem, Mahsana; Haley, Joseph; Halladjian, Garabed; Hallewell, Gregory David; Hamacher, Klaus; Hamal, Petr; Hamano, Kenji; Hamilton, Andrew; Hamity, Guillermo Nicolas; Hamnett, Phillip George; Han, Liang; Han, Shuo; Hanagaki, Kazunori; Hanawa, Keita; Hance, Michael; Haney, Bijan; Hanke, Paul; Hansen, Jørgen Beck; Hansen, Jorn Dines; Hansen, Maike Christina; Hansen, Peter Henrik; Hara, Kazuhiko; Hard, Andrew; Harenberg, Torsten; Hariri, Faten; Harkusha, Siarhei; Harrington, Robert; Harrison, Paul Fraser; Hartjes, Fred; Hartmann, Nikolai Marcel; Hasegawa, Makoto; Hasegawa, Yoji; Hasib, Ahmed; Hassani, Samira; Haug, Sigve; Hauser, Reiner; Hauswald, Lorenz; Havener, Laura Brittany; Havranek, Miroslav; Hawkes, Christopher; Hawkings, Richard John; Hayakawa, Daiki; Hayden, Daniel; Hays, Chris; Hays, Jonathan Michael; Hayward, Helen; Haywood, Stephen; Head, Simon; Heck, Tobias; Hedberg, Vincent; Heelan, Louise; Heidegger, Kim Katrin; Heim, Sarah; Heim, Timon; Heinemann, Beate; Heinrich, Jochen Jens; Heinrich, Lukas; Heinz, Christian; Hejbal, Jiri; Helary, Louis; Held, Alexander; Hellman, Sten; Helsens, Clement; Henderson, James; Henderson, Robert; Heng, Yang; Henkelmann, Steffen; Henriques Correia, Ana Maria; Henrot-Versille, Sophie; Herbert, Geoffrey Henry; Herde, Hannah; Herget, Verena; Hernández Jiménez, Yesenia; Herten, Gregor; Hertenberger, Ralf; Hervas, Luis; Herwig, Theodor Christian; Hesketh, Gavin Grant; Hessey, Nigel; Hetherly, Jeffrey Wayne; Higashino, Satoshi; Higón-Rodriguez, Emilio; Hill, Ewan; Hill, John; Hiller, Karl Heinz; Hillier, Stephen; Hinchliffe, Ian; Hirose, Minoru; Hirschbuehl, Dominic; Hiti, Bojan; Hladik, Ondrej; Hoad, Xanthe; Hobbs, John; Hod, Noam; Hodgkinson, Mark; Hodgson, Paul; Hoecker, Andreas; Hoeferkamp, Martin; Hoenig, Friedrich; Hohn, David; Holmes, Tova Ray; Homann, Michael; Honda, Shunsuke; Honda, Takuya; Hong, Tae Min; Hooberman, Benjamin Henry; Hopkins, Walter; Horii, Yasuyuki; Horton, Arthur James; Hostachy, Jean-Yves; Hou, Suen; Hoummada, Abdeslam; Howarth, James; Hoya, Joaquin; Hrabovsky, Miroslav; Hristova, Ivana; Hrivnac, Julius; Hryn'ova, Tetiana; Hrynevich, Aliaksei; Hsu, Pai-hsien Jennifer; Hsu, Shih-Chieh; Hu, Qipeng; Hu, Shuyang; Huang, Yanping; Hubacek, Zdenek; Hubaut, Fabrice; Huegging, Fabian; Huffman, Todd Brian; Hughes, Emlyn; Hughes, Gareth; Huhtinen, Mika; Huo, Peng; Huseynov, Nazim; Huston, Joey; Huth, John; Iacobucci, Giuseppe; Iakovidis, Georgios; Ibragimov, Iskander; Iconomidou-Fayard, Lydia; Iengo, Paolo; Igonkina, Olga; Iizawa, Tomoya; Ikegami, Yoichi; Ikeno, Masahiro; Ilchenko, Yuriy; Iliadis, Dimitrios; Ilic, Nikolina; Introzzi, Gianluca; Ioannou, Pavlos; Iodice, Mauro; Iordanidou, Kalliopi; Ippolito, Valerio; Ishijima, Naoki; Ishino, Masaya; Ishitsuka, Masaki; Issever, Cigdem; Istin, Serhat; Ito, Fumiaki; Iturbe Ponce, Julia Mariana; Iuppa, Roberto; Iwasaki, Hiroyuki; Izen, Joseph; Izzo, Vincenzo; Jabbar, Samina; Jackson, Paul; Jain, Vivek; Jakobi, Katharina Bianca; Jakobs, Karl; Jakobsen, Sune; Jakoubek, Tomas; Jamin, David Olivier; Jana, Dilip; Jansky, Roland; Janssen, Jens; Janus, Michel; Janus, Piotr Andrzej; Jarlskog, Göran; Javadov, Namig; Javůrek, Tomáš; Javurkova, Martina; Jeanneau, Fabien; Jeanty, Laura; Jejelava, Juansher; Jelinskas, Adomas; Jenni, Peter; Jeske, Carl; Jézéquel, Stéphane; Ji, Haoshuang; Jia, Jiangyong; Jiang, Hai; Jiang, Yi; Jiang, Zihao; Jiggins, Stephen; Jimenez Pena, Javier; Jin, Shan; Jinaru, Adam; Jinnouchi, Osamu; Jivan, Harshna; Johansson, Per; Johns, Kenneth; Johnson, Christian; Johnson, William Joseph; Jon-And, Kerstin; Jones, Roger; Jones, Sarah; Jones, Tim; Jongmanns, Jan; Jorge, Pedro; Jovicevic, Jelena; Ju, Xiangyang; Juste Rozas, Aurelio; Köhler, Markus Konrad; Kaczmarska, Anna; Kado, Marumi; Kagan, Harris; Kagan, Michael; Kahn, Sebastien Jonathan; Kaji, Toshiaki; Kajomovitz, Enrique; Kalderon, Charles William; Kaluza, Adam; Kama, Sami; Kamenshchikov, Andrey; Kanaya, Naoko; Kaneti, Steven; Kanjir, Luka; Kantserov, Vadim; Kanzaki, Junichi; Kaplan, Benjamin; Kaplan, Laser Seymour; Kar, Deepak; Karakostas, Konstantinos; Karastathis, Nikolaos; Kareem, Mohammad Jawad; Karentzos, Efstathios; Karpov, Sergey; Karpova, Zoya; Karthik, Krishnaiyengar; Kartvelishvili, Vakhtang; Karyukhin, Andrey; Kasahara, Kota; Kashif, Lashkar; Kass, Richard; Kastanas, Alex; Kataoka, Yousuke; Kato, Chikuma; Katre, Akshay; Katzy, Judith; Kawade, Kentaro; Kawagoe, Kiyotomo; Kawamoto, Tatsuo; Kawamura, Gen; Kay, Ellis; Kazanin, Vassili; Keeler, Richard; Kehoe, Robert; Keller, John; Kempster, Jacob Julian; Keoshkerian, Houry; Kepka, Oldrich; Kerševan, Borut Paul; Kersten, Susanne; Keyes, Robert; Khader, Mazin; Khalil-zada, Farkhad; Khanov, Alexander; Kharlamov, Alexey; Kharlamova, Tatyana; Khodinov, Alexander; Khoo, Teng Jian; Khovanskiy, Valery; Khramov, Evgeniy; Khubua, Jemal; Kido, Shogo; Kilby, Callum; Kim, Hee Yeun; Kim, Shinhong; Kim, Young-Kee; Kimura, Naoki; Kind, Oliver Maria; King, Barry; Kirchmeier, David; Kirk, Julie; Kiryunin, Andrey; Kishimoto, Tomoe; Kisielewska, Danuta; Kiuchi, Kenji; Kivernyk, Oleh; Kladiva, Eduard; Klapdor-Kleingrothaus, Thorwald; Klein, Matthew Henry; Klein, Max; Klein, Uta; Kleinknecht, Konrad; Klimek, Pawel; Klimentov, Alexei; Klingenberg, Reiner; Klingl, Tobias; Klioutchnikova, Tatiana; Kluge, Eike-Erik; Kluit, Peter; Kluth, Stefan; Knapik, Joanna; Kneringer, Emmerich; Knoops, Edith; Knue, Andrea; Kobayashi, Aine; Kobayashi, Dai; Kobayashi, Tomio; Kobel, Michael; Kocian, Martin; Kodys, Peter; Koffas, Thomas; Koffeman, Els; Köhler, Nicolas Maximilian; Koi, Tatsumi; Kolb, Mathis; Koletsou, Iro; Komar, Aston; Komori, Yuto; Kondo, Takahiko; Kondrashova, Nataliia; Köneke, Karsten; König, Adriaan; Kono, Takanori; Konoplich, Rostislav; Konstantinidis, Nikolaos; Kopeliansky, Revital; Koperny, Stefan; Kopp, Anna Katharina; Korcyl, Krzysztof; Kordas, Kostantinos; Korn, Andreas; Korol, Aleksandr; Korolkov, Ilya; Korolkova, Elena; Kortner, Oliver; Kortner, Sandra; Kosek, Tomas; Kostyukhin, Vadim; Kotwal, Ashutosh; Koulouris, Aimilianos; Kourkoumeli-Charalampidi, Athina; Kourkoumelis, Christine; Kourlitis, Evangelos; Kouskoura, Vasiliki; Kowalewska, Anna Bozena; Kowalewski, Robert Victor; Kowalski, Tadeusz; Kozakai, Chihiro; Kozanecki, Witold; Kozhin, Anatoly; Kramarenko, Viktor; Kramberger, Gregor; Krasnopevtsev, Dimitrii; Krasznahorkay, Attila; Krauss, Dominik; Kravchenko, Anton; Kremer, Jakub Andrzej; Kretz, Moritz; Kretzschmar, Jan; Kreutzfeldt, Kristof; Krieger, Peter; Krizka, Karol; Kroeninger, Kevin; Kroha, Hubert; Kroll, Joe; Kroseberg, Juergen; Krstic, Jelena; Kruchonak, Uladzimir; Krüger, Hans; Krumnack, Nils; Kruse, Mark; Kruskal, Michael; Kubota, Takashi; Kucuk, Hilal; Kuday, Sinan; Kuechler, Jan Thomas; Kuehn, Susanne; Kugel, Andreas; Kuger, Fabian; Kuhl, Thorsten; Kukhtin, Victor; Kukla, Romain; Kulchitsky, Yuri; Kuleshov, Sergey; Kulinich, Yakov Petrovich; Kuna, Marine; Kunigo, Takuto; Kupco, Alexander; Kuprash, Oleg; Kurashige, Hisaya; Kurchaninov, Leonid; Kurochkin, Yurii; Kurth, Matthew Glenn; Kus, Vlastimil; Kuwertz, Emma Sian; Kuze, Masahiro; Kvita, Jiri; Kwan, Tony; Kyriazopoulos, Dimitrios; La Rosa, Alessandro; La Rosa Navarro, Jose Luis; La Rotonda, Laura; Lacasta, Carlos; Lacava, Francesco; Lacey, James; Lacker, Heiko; Lacour, Didier; Ladygin, Evgueni; Lafaye, Remi; Laforge, Bertrand; Lagouri, Theodota; Lai, Stanley; Lammers, Sabine; Lampl, Walter; Lançon, Eric; Landgraf, Ulrich; Landon, Murrough; Lanfermann, Marie Christine; Lang, Valerie Susanne; Lange, J örn Christian; Lankford, Andrew; Lanni, Francesco; Lantzsch, Kerstin; Lanza, Agostino; Lapertosa, Alessandro; Laplace, Sandrine; Laporte, Jean-Francois; Lari, Tommaso; Lasagni Manghi, Federico; Lassnig, Mario; Laurelli, Paolo; Lavrijsen, Wim; Law, Alexander; Laycock, Paul; Lazovich, Tomo; Lazzaroni, Massimo; Le, Brian; Le Dortz, Olivier; Le Guirriec, Emmanuel; Le Quilleuc, Eloi; LeBlanc, Matthew Edgar; LeCompte, Thomas; Ledroit-Guillon, Fabienne; Lee, Claire Alexandra; Lee, Shih-Chang; Lee, Lawrence; Lefebvre, Benoit; Lefebvre, Guillaume; Lefebvre, Michel; Legger, Federica; Leggett, Charles; Lehan, Allan; Lehmann Miotto, Giovanna; Lei, Xiaowen; Leight, William Axel; Leite, Marco Aurelio Lisboa; Leitner, Rupert; Lellouch, Daniel; Lemmer, Boris; Leney, Katharine; Lenz, Tatjana; Lenzi, Bruno; Leone, Robert; Leone, Sandra; Leonidopoulos, Christos; Lerner, Giuseppe; Leroy, Claude; Lesage, Arthur; Lester, Christopher; Levchenko, Mikhail; Levêque, Jessica; Levin, Daniel; Levinson, Lorne; Levy, Mark; Lewis, Dave; Leyton, Michael; Li, Bing; Li, Changqiao; Li, Haifeng; Li, Lei; Li, Liang; Li, Qi; Li, Shu; Li, Xingguo; Li, Yichen; Liang, Zhijun; Liberti, Barbara; Liblong, Aaron; Lie, Ki; Liebal, Jessica; Liebig, Wolfgang; Limosani, Antonio; Lin, Simon; Lin, Tai-Hua; Lindquist, Brian Edward; Lionti, Anthony Eric; Lipeles, Elliot; Lipniacka, Anna; Lisovyi, Mykhailo; Liss, Tony; Lister, Alison; Litke, Alan; Liu, Bo; Liu, Hao; Liu, Hongbin; Liu, Jian; Liu, Jianbei; Liu, Kun; Liu, Lulu; Liu, Minghui; Liu, Yanlin; Liu, Yanwen; Livan, Michele; Lleres, Annick; Llorente Merino, Javier; Lloyd, Stephen; Lo, Cheuk Yee; Lo Sterzo, Francesco; Lobodzinska, Ewelina Maria; Loch, Peter; Loebinger, Fred; Loew, Kevin Michael; Loginov, Andrey; Lohse, Thomas; Lohwasser, Kristin; Lokajicek, Milos; Long, Brian Alexander; Long, Jonathan David; Long, Robin Eamonn; Longo, Luigi; Looper, Kristina Anne; Lopez, Jorge; Lopez Mateos, David; Lopez Paz, Ivan; Lopez Solis, Alvaro; Lorenz, Jeanette; Lorenzo Martinez, Narei; Losada, Marta; Lösel, Philipp Jonathan; Lou, XinChou; Lounis, Abdenour; Love, Jeremy; Love, Peter; Lu, Haonan; Lu, Nan; Lu, Yun-Ju; Lubatti, Henry; Luci, Claudio; Lucotte, Arnaud; Luedtke, Christian; Luehring, Frederick; Lukas, Wolfgang; Luminari, Lamberto; Lundberg, Olof; Lund-Jensen, Bengt; Luzi, Pierre Marc; Lynn, David; Lysak, Roman; Lytken, Else; Lyubushkin, Vladimir; Ma, Hong; Ma, Lian Liang; Ma, Yanhui; Maccarrone, Giovanni; Macchiolo, Anna; Macdonald, Calum Michael; Maček, Boštjan; Machado Miguens, Joana; Madaffari, Daniele; Madar, Romain; Maddocks, Harvey Jonathan; Mader, Wolfgang; Madsen, Alexander; Maeda, Junpei; Maeland, Steffen; Maeno, Tadashi; Maevskiy, Artem; Magradze, Erekle; Mahlstedt, Joern; Maiani, Camilla; Maidantchik, Carmen; Maier, Andreas Alexander; Maier, Thomas; Maio, Amélia; Majewski, Stephanie; Makida, Yasuhiro; Makovec, Nikola; Malaescu, Bogdan; Malecki, Pawel; Maleev, Victor; Malek, Fairouz; Mallik, Usha; Malon, David; Malone, Claire; Maltezos, Stavros; Malyukov, Sergei; Mamuzic, Judita; Mancini, Giada; Mandelli, Luciano; Mandić, Igor; Maneira, José; Manhaes de Andrade Filho, Luciano; Manjarres Ramos, Joany; Mann, Alexander; Manousos, Athanasios; Mansoulie, Bruno; Mansour, Jason Dhia; Mantifel, Rodger; Mantoani, Matteo; Manzoni, Stefano; Mapelli, Livio; Marceca, Gino; March, Luis; Marchiori, Giovanni; Marcisovsky, Michal; Marjanovic, Marija; Marley, Daniel; Marroquim, Fernando; Marsden, Stephen Philip; Marshall, Zach; Martensson, Mikael; Marti-Garcia, Salvador; Martin, Christopher Blake; Martin, Tim; Martin, Victoria Jane; Martin dit Latour, Bertrand; Martinez, Mario; Martinez Outschoorn, Verena; Martin-Haugh, Stewart; Martoiu, Victor Sorin; Martyniuk, Alex; Marzin, Antoine; Masetti, Lucia; Mashimo, Tetsuro; Mashinistov, Ruslan; Masik, Jiri; Maslennikov, Alexey; Massa, Lorenzo; Mastrandrea, Paolo; Mastroberardino, Anna; Masubuchi, Tatsuya; Mättig, Peter; Maurer, Julien; Maxfield, Stephen; Maximov, Dmitriy; Mazini, Rachid; Maznas, Ioannis; Mazza, Simone Michele; Mc Fadden, Neil Christopher; Mc Goldrick, Garrin; Mc Kee, Shawn Patrick; McCarn, Allison; McCarthy, Robert; McCarthy, Tom; McClymont, Laurie; McDonald, Emily; Mcfayden, Josh; Mchedlidze, Gvantsa; McMahon, Steve; McNamara, Peter Charles; McPherson, Robert; Meehan, Samuel; Megy, Theo Jean; Mehlhase, Sascha; Mehta, Andrew; Meideck, Thomas; Meier, Karlheinz; Meineck, Christian; Meirose, Bernhard; Melini, Davide; Mellado Garcia, Bruce Rafael; Melo, Matej; Meloni, Federico; Menary, Stephen Burns; Meng, Lingxin; Meng, Xiangting; Mengarelli, Alberto; Menke, Sven; Meoni, Evelin; Mergelmeyer, Sebastian; Mermod, Philippe; Merola, Leonardo; Meroni, Chiara; Merritt, Frank; Messina, Andrea; Metcalfe, Jessica; Mete, Alaettin Serhan; Meyer, Christopher; Meyer, Jean-Pierre; Meyer, Jochen; Meyer Zu Theenhausen, Hanno; Miano, Fabrizio; Middleton, Robin; Miglioranzi, Silvia; Mijović, Liza; Mikenberg, Giora; Mikestikova, Marcela; Mikuž, Marko; Milesi, Marco; Milic, Adriana; Miller, David; Mills, Corrinne; Milov, Alexander; Milstead, David; Minaenko, Andrey; Minami, Yuto; Minashvili, Irakli; Mincer, Allen; Mindur, Bartosz; Mineev, Mikhail; Minegishi, Yuji; Ming, Yao; Mir, Lluisa-Maria; Mistry, Khilesh; Mitani, Takashi; Mitrevski, Jovan; Mitsou, Vasiliki A; Miucci, Antonio; Miyagawa, Paul; Mizukami, Atsushi; Mjörnmark, Jan-Ulf; Mlynarikova, Michaela; Moa, Torbjoern; Mochizuki, Kazuya; Mogg, Philipp; Mohapatra, Soumya; Molander, Simon; Moles-Valls, Regina; Monden, Ryutaro; Mondragon, Matthew Craig; Mönig, Klaus; Monk, James; Monnier, Emmanuel; Montalbano, Alyssa; Montejo Berlingen, Javier; Monticelli, Fernando; Monzani, Simone; Moore, Roger; Morange, Nicolas; Moreno, Deywis; Moreno Llácer, María; Morettini, Paolo; Morgenstern, Stefanie; Mori, Daniel; Mori, Tatsuya; Morii, Masahiro; Morinaga, Masahiro; Morisbak, Vanja; Morley, Anthony Keith; Mornacchi, Giuseppe; Morris, John; Morvaj, Ljiljana; Moschovakos, Paris; Mosidze, Maia; Moss, Harry James; Moss, Josh; Motohashi, Kazuki; Mount, Richard; Mountricha, Eleni; Moyse, Edward; Muanza, Steve; Mudd, Richard; Mueller, Felix; Mueller, James; Mueller, Ralph Soeren Peter; Muenstermann, Daniel; Mullen, Paul; Mullier, Geoffrey; Munoz Sanchez, Francisca Javiela; Murray, Bill; Musheghyan, Haykuhi; Muškinja, Miha; Myagkov, Alexey; Myska, Miroslav; Nachman, Benjamin Philip; Nackenhorst, Olaf; Nagai, Koichi; Nagai, Ryo; Nagano, Kunihiro; Nagasaka, Yasushi; Nagata, Kazuki; Nagel, Martin; Nagy, Elemer; Nairz, Armin Michael; Nakahama, Yu; Nakamura, Koji; Nakamura, Tomoaki; Nakano, Itsuo; Naranjo Garcia, Roger Felipe; Narayan, Rohin; Narrias Villar, Daniel Isaac; Naryshkin, Iouri; Naumann, Thomas; Navarro, Gabriela; Nayyar, Ruchika; Neal, Homer; Nechaeva, Polina; Neep, Thomas James; Negri, Andrea; Negrini, Matteo; Nektarijevic, Snezana; Nellist, Clara; Nelson, Andrew; Nelson, Michael Edward; Nemecek, Stanislav; Nemethy, Peter; Nepomuceno, Andre Asevedo; Nessi, Marzio; Neubauer, Mark; Neumann, Manuel; Neves, Ricardo; Newman, Paul; Ng, Tsz Yu; Nguyen Manh, Tuan; Nickerson, Richard; Nicolaidou, Rosy; Nielsen, Jason; Nikolaenko, Vladimir; Nikolic-Audit, Irena; Nikolopoulos, Konstantinos; Nilsen, Jon Kerr; Nilsson, Paul; Ninomiya, Yoichi; Nisati, Aleandro; Nishu, Nishu; Nisius, Richard; Nobe, Takuya; Noguchi, Yohei; Nomachi, Masaharu; Nomidis, Ioannis; Nomura, Marcelo Ayumu; Nooney, Tamsin; Nordberg, Markus; Norjoharuddeen, Nurfikri; Novgorodova, Olga; Nowak, Sebastian; Nozaki, Mitsuaki; Nozka, Libor; Ntekas, Konstantinos; Nurse, Emily; Nuti, Francesco; O'Neil, Dugan; O'Rourke, Abigail Alexandra; O'Shea, Val; Oakham, Gerald; Oberlack, Horst; Obermann, Theresa; Ocariz, Jose; Ochi, Atsuhiko; Ochoa, Ines; Ochoa-Ricoux, Juan Pedro; Oda, Susumu; Odaka, Shigeru; Ogren, Harold; Oh, Alexander; Oh, Seog; Ohm, Christian; Ohman, Henrik; Oide, Hideyuki; Okawa, Hideki; Okumura, Yasuyuki; Okuyama, Toyonobu; Olariu, Albert; Oleiro Seabra, Luis Filipe; Olivares Pino, Sebastian Andres; Oliveira Damazio, Denis; Olszewski, Andrzej; Olszowska, Jolanta; Onofre, António; Onogi, Kouta; Onyisi, Peter; Oreglia, Mark; Oren, Yona; Orestano, Domizia; Orlando, Nicola; Orr, Robert; Osculati, Bianca; Ospanov, Rustem; Otero y Garzon, Gustavo; Otono, Hidetoshi; Ouchrif, Mohamed; Ould-Saada, Farid; Ouraou, Ahmimed; Oussoren, Koen Pieter; Ouyang, Qun; Owen, Mark; Owen, Rhys Edward; Ozcan, Veysi Erkcan; Ozturk, Nurcan; Pachal, Katherine; Pacheco Pages, Andres; Pacheco Rodriguez, Laura; Padilla Aranda, Cristobal; Pagan Griso, Simone; Paganini, Michela; Paige, Frank; Pais, Preema; Palacino, Gabriel; Palazzo, Serena; Palestini, Sandro; Palka, Marek; Pallin, Dominique; Panagiotopoulou, Evgenia; Panagoulias, Ilias; Pandini, Carlo Enrico; Panduro Vazquez, William; Pani, Priscilla; Panitkin, Sergey; Pantea, Dan; Paolozzi, Lorenzo; Papadopoulou, Theodora; Papageorgiou, Konstantinos; Paramonov, Alexander; Paredes Hernandez, Daniela; Parker, Adam Jackson; Parker, Michael Andrew; Parker, Kerry Ann; Parodi, Fabrizio; Parsons, John; Parzefall, Ulrich; Pascuzzi, Vincent; Pasner, Jacob Martin; Pasqualucci, Enrico; Passaggio, Stefano; Pastore, Francesca; Pataraia, Sophio; Pater, Joleen; Pauly, Thilo; Pearce, James; Pearson, Benjamin; Pedersen, Lars Egholm; Pedraza Lopez, Sebastian; Pedro, Rute; Peleganchuk, Sergey; Penc, Ondrej; Peng, Cong; Peng, Haiping; Penwell, John; Peralva, Bernardo; Perego, Marta Maria; Perepelitsa, Dennis; Perini, Laura; Pernegger, Heinz; Perrella, Sabrina; Peschke, Richard; Peshekhonov, Vladimir; Peters, Krisztian; Peters, Yvonne; Petersen, Brian; Petersen, Troels; Petit, Elisabeth; Petridis, Andreas; Petridou, Chariclia; Petroff, Pierre; Petrolo, Emilio; Petrov, Mariyan; Petrucci, Fabrizio; Pettersson, Nora Emilia; Peyaud, Alan; Pezoa, Raquel; Phillips, Peter William; Piacquadio, Giacinto; Pianori, Elisabetta; Picazio, Attilio; Piccaro, Elisa; Pickering, Mark Andrew; Piegaia, Ricardo; Pilcher, James; Pilkington, Andrew; Pin, Arnaud Willy J; Pinamonti, Michele; Pinfold, James; Pirumov, Hayk; Pitt, Michael; Plazak, Lukas; Pleier, Marc-Andre; Pleskot, Vojtech; Plotnikova, Elena; Pluth, Daniel; Podberezko, Pavel; Poettgen, Ruth; Poggioli, Luc; Pohl, David-leon; Polesello, Giacomo; Poley, Anne-luise; Policicchio, Antonio; Polifka, Richard; Polini, Alessandro; Pollard, Christopher Samuel; Polychronakos, Venetios; Pommès, Kathy; Ponomarenko, Daniil; Pontecorvo, Ludovico; Pope, Bernard; Popeneciu, Gabriel Alexandru; Poppleton, Alan; Pospisil, Stanislav; Potamianos, Karolos; Potrap, Igor; Potter, Christina; Potter, Christopher; Poulard, Gilbert; Poveda, Joaquin; Pozo Astigarraga, Mikel Eukeni; Pralavorio, Pascal; Pranko, Aliaksandr; Prell, Soeren; Price, Darren; Price, Lawrence; Primavera, Margherita; Prince, Sebastien; Proklova, Nadezda; Prokofiev, Kirill; Prokoshin, Fedor; Protopopescu, Serban; Proudfoot, James; Przybycien, Mariusz; Puddu, Daniele; Puri, Akshat; Puzo, Patrick; Qian, Jianming; Qin, Gang; Qin, Yang; Quadt, Arnulf; Quayle, William; Queitsch-Maitland, Michaela; Quilty, Donnchadha; Raddum, Silje; Radeka, Veljko; Radescu, Voica; Radhakrishnan, Sooraj Krishnan; Radloff, Peter; Rados, Pere; Ragusa, Francesco; Rahal, Ghita; Raine, John Andrew; Rajagopalan, Srinivasan; Rangel-Smith, Camila; Ratti, Maria Giulia; Rauch, Daniel; Rauscher, Felix; Rave, Stefan; Ravenscroft, Thomas; Ravinovich, Ilia; Rawling, Jacob Henry; Raymond, Michel; Read, Alexander Lincoln; Readioff, Nathan Peter; Reale, Marilea; Rebuzzi, Daniela; Redelbach, Andreas; Redlinger, George; Reece, Ryan; Reed, Robert; Reeves, Kendall; Rehnisch, Laura; Reichert, Joseph; Reiss, Andreas; Rembser, Christoph; Ren, Huan; Rescigno, Marco; Resconi, Silvia; Resseguie, Elodie Deborah; Rettie, Sebastien; Reynolds, Elliot; Rezanova, Olga; Reznicek, Pavel; Rezvani, Reyhaneh; Richter, Robert; Richter, Stefan; Richter-Was, Elzbieta; Ricken, Oliver; Ridel, Melissa; Rieck, Patrick; Riegel, Christian Johann; Rieger, Julia; Rifki, Othmane; Rijssenbeek, Michael; Rimoldi, Adele; Rimoldi, Marco; Rinaldi, Lorenzo; Ristić, Branislav; Ritsch, Elmar; Riu, Imma; Rizatdinova, Flera; Rizvi, Eram; Rizzi, Chiara; Roberts, Rhys Thomas; Robertson, Steven; Robichaud-Veronneau, Andree; Robinson, Dave; Robinson, James; Robson, Aidan; Roda, Chiara; Rodina, Yulia; Rodriguez Perez, Andrea; Rodriguez Rodriguez, Daniel; Roe, Shaun; Rogan, Christopher Sean; Røhne, Ole; Roloff, Jennifer; Romaniouk, Anatoli; Romano, Marino; Romano Saez, Silvestre Marino; Romero Adam, Elena; Rompotis, Nikolaos; Ronzani, Manfredi; Roos, Lydia; Rosati, Stefano; Rosbach, Kilian; Rose, Peyton; Rosien, Nils-Arne; Rossetti, Valerio; Rossi, Elvira; Rossi, Leonardo Paolo; Rosten, Jonatan; Rosten, Rachel; Rotaru, Marina; Roth, Itamar; Rothberg, Joseph; Rousseau, David; Rozanov, Alexandre; Rozen, Yoram; Ruan, Xifeng; Rubbo, Francesco; Rühr, Frederik; Ruiz-Martinez, Aranzazu; Rurikova, Zuzana; Rusakovich, Nikolai; Ruschke, Alexander; Russell, Heather; Rutherfoord, John; Ruthmann, Nils; Ryabov, Yury; Rybar, Martin; Rybkin, Grigori; Ryu, Soo; Ryzhov, Andrey; Rzehorz, Gerhard Ferdinand; Saavedra, Aldo; Sabato, Gabriele; Sacerdoti, Sabrina; Sadrozinski, Hartmut; Sadykov, Renat; Safai Tehrani, Francesco; Saha, Puja; Sahinsoy, Merve; Saimpert, Matthias; Saito, Masahiko; Saito, Tomoyuki; Sakamoto, Hiroshi; Sakurai, Yuki; Salamanna, Giuseppe; Salazar Loyola, Javier Esteban; Salek, David; Sales De Bruin, Pedro Henrique; Salihagic, Denis; Salnikov, Andrei; Salt, José; Salvatore, Daniela; Salvatore, Pasquale Fabrizio; Salvucci, Antonio; Salzburger, Andreas; Sammel, Dirk; Sampsonidis, Dimitrios; Sánchez, Javier; Sanchez Martinez, Victoria; Sanchez Pineda, Arturo Rodolfo; Sandaker, Heidi; Sandbach, Ruth Laura; Sander, Christian Oliver; Sandhoff, Marisa; Sandoval, Carlos; Sankey, Dave; Sannino, Mario; Sansoni, Andrea; Santoni, Claudio; Santonico, Rinaldo; Santos, Helena; Santoyo Castillo, Itzebelt; Sapp, Kevin; Sapronov, Andrey; Saraiva, João; Sarrazin, Bjorn; Sasaki, Osamu; Sato, Koji; Sauvan, Emmanuel; Savage, Graham; Savard, Pierre; Savic, Natascha; Sawyer, Craig; Sawyer, Lee; Saxon, James; Sbarra, Carla; Sbrizzi, Antonio; Scanlon, Tim; Scannicchio, Diana; Scarcella, Mark; Scarfone, Valerio; Schaarschmidt, Jana; Schacht, Peter; Schachtner, Balthasar Maria; Schaefer, Douglas; Schaefer, Leigh; Schaefer, Ralph; Schaeffer, Jan; Schaepe, Steffen; Schaetzel, Sebastian; Schäfer, Uli; Schaffer, Arthur; Schaile, Dorothee; Schamberger, R Dean; Scharf, Veit; Schegelsky, Valery; Scheirich, Daniel; Schernau, Michael; Schiavi, Carlo; Schier, Sheena; Schildgen, Lara Katharina; Schillo, Christian; Schioppa, Marco; Schlenker, Stefan; Schmidt-Sommerfeld, Korbinian Ralf; Schmieden, Kristof; Schmitt, Christian; Schmitt, Stefan; Schmitz, Simon; Schnoor, Ulrike; Schoeffel, Laurent; Schoening, Andre; Schoenrock, Bradley Daniel; Schopf, Elisabeth; Schott, Matthias; Schouwenberg, Jeroen; Schovancova, Jaroslava; Schramm, Steven; Schuh, Natascha; Schulte, Alexandra; Schultens, Martin Johannes; Schultz-Coulon, Hans-Christian; Schulz, Holger; Schumacher, Markus; Schumm, Bruce; Schune, Philippe; Schwartzman, Ariel; Schwarz, Thomas Andrew; Schweiger, Hansdieter; Schwemling, Philippe; Schwienhorst, Reinhard; Schwindling, Jerome; Schwindt, Thomas; Sciandra, Andrea; Sciolla, Gabriella; Scuri, Fabrizio; Scutti, Federico; Searcy, Jacob; Seema, Pienpen; Seidel, Sally; Seiden, Abraham; Seixas, José; Sekhniaidze, Givi; Sekhon, Karishma; Sekula, Stephen; Semprini-Cesari, Nicola; Serfon, Cedric; Serin, Laurent; Serkin, Leonid; Sessa, Marco; Seuster, Rolf; Severini, Horst; Sfiligoj, Tina; Sforza, Federico; Sfyrla, Anna; Shabalina, Elizaveta; Shaikh, Nabila Wahab; Shan, Lianyou; Shang, Ruo-yu; Shank, James; Shapiro, Marjorie; Shatalov, Pavel; Shaw, Kate; Shaw, Savanna Marie; Shcherbakova, Anna; Shehu, Ciwake Yusufu; Shen, Yu-Ting; Sherwood, Peter; Shi, Liaoshan; Shimizu, Shima; Shimmin, Chase Owen; Shimojima, Makoto; Shirabe, Shohei; Shiyakova, Mariya; Shlomi, Jonathan; Shmeleva, Alevtina; Shoaleh Saadi, Diane; Shochet, Mel; Shojaii, Seyed Ruhollah; Shope, David Richard; Shrestha, Suyog; Shulga, Evgeny; Shupe, Michael; Sicho, Petr; Sickles, Anne Marie; Sidebo, Per Edvin; Sideras Haddad, Elias; Sidiropoulou, Ourania; Sidorov, Dmitri; Sidoti, Antonio; Siegert, Frank; Sijacki, Djordje; Silva, José; Silverstein, Samuel; Simak, Vladislav; Simic, Ljiljana; Simion, Stefan; Simioni, Eduard; Simmons, Brinick; Simon, Manuel; Sinervo, Pekka; Sinev, Nikolai; Sioli, Maximiliano; Siragusa, Giovanni; Siral, Ismet; Sivoklokov, Serguei; Sjölin, Jörgen; Skinner, Malcolm Bruce; Skubic, Patrick; Slater, Mark; Slavicek, Tomas; Slawinska, Magdalena; Sliwa, Krzysztof; Slovak, Radim; Smakhtin, Vladimir; Smart, Ben; Smiesko, Juraj; Smirnov, Nikita; Smirnov, Sergei; Smirnov, Yury; Smirnova, Lidia; Smirnova, Oxana; Smith, Joshua Wyatt; Smith, Matthew; Smith, Russell; Smizanska, Maria; Smolek, Karel; Snesarev, Andrei; Snyder, Ian Michael; Snyder, Scott; Sobie, Randall; Socher, Felix; Soffer, Abner; Soh, Dart-yin; Sokhrannyi, Grygorii; Solans Sanchez, Carlos; Solar, Michael; Soldatov, Evgeny; Soldevila, Urmila; Solodkov, Alexander; Soloshenko, Alexei; Solovyanov, Oleg; Solovyev, Victor; Sommer, Philip; Son, Hyungsuk; Song, Hong Ye; Sopczak, Andre; Sorin, Veronica; Sosa, David; Sotiropoulou, Calliope Louisa; Soualah, Rachik; Soukharev, Andrey; South, David; Sowden, Benjamin; Spagnolo, Stefania; Spalla, Margherita; Spangenberg, Martin; Spanò, Francesco; Sperlich, Dennis; Spettel, Fabian; Spieker, Thomas Malte; Spighi, Roberto; Spigo, Giancarlo; Spiller, Laurence Anthony; Spousta, Martin; St Denis, Richard Dante; Stabile, Alberto; Stamen, Rainer; Stamm, Soren; Stanecka, Ewa; Stanek, Robert; Stanescu, Cristian; Stanitzki, Marcel Michael; Stapnes, Steinar; Starchenko, Evgeny; Stark, Giordon; Stark, Jan; Stark, Simon Holm; Staroba, Pavel; Starovoitov, Pavel; Stärz, Steffen; Staszewski, Rafal; Steinberg, Peter; Stelzer, Bernd; Stelzer, Harald Joerg; Stelzer-Chilton, Oliver; Stenzel, Hasko; Stewart, Graeme; Stillings, Jan Andre; Stockton, Mark; Stoebe, Michael; Stoicea, Gabriel; Stolte, Philipp; Stonjek, Stefan; Stradling, Alden; Straessner, Arno; Stramaglia, Maria Elena; Strandberg, Jonas; Strandberg, Sara; Strandlie, Are; Strauss, Michael; Strizenec, Pavol; Ströhmer, Raimund; Strom, David; Stroynowski, Ryszard; Strubig, Antonia; Stucci, Stefania Antonia; Stugu, Bjarne; Styles, Nicholas Adam; Su, Dong; Su, Jun; Suchek, Stanislav; Sugaya, Yorihito; Suk, Michal; Sulin, Vladimir; Sultansoy, Saleh; Sumida, Toshi; Sun, Siyuan; Sun, Xiaohu; Suruliz, Kerim; Suster, Carl; Sutton, Mark; Suzuki, Shota; Svatos, Michal; Swiatlowski, Maximilian; Swift, Stewart Patrick; Sydorenko, Alexander; Sykora, Ivan; Sykora, Tomas; Ta, Duc; Tackmann, Kerstin; Taenzer, Joe; Taffard, Anyes; Tafirout, Reda; Taiblum, Nimrod; Takai, Helio; Takashima, Ryuichi; Takeshita, Tohru; Takubo, Yosuke; Talby, Mossadek; Talyshev, Alexey; Tanaka, Junichi; Tanaka, Masahiro; Tanaka, Reisaburo; Tanaka, Shuji; Tanioka, Ryo; Tannenwald, Benjamin Bordy; Tapia Araya, Sebastian; Tapprogge, Stefan; Tarem, Shlomit; Tartarelli, Giuseppe Francesco; Tas, Petr; Tasevsky, Marek; Tashiro, Takuya; Tassi, Enrico; Tavares Delgado, Ademar; Tayalati, Yahya; Taylor, Aaron; Taylor, Geoffrey; Taylor, Pierre Thor Elliot; Taylor, Wendy; Teixeira-Dias, Pedro; Temple, Darren; Ten Kate, Herman; Teng, Ping-Kun; Teoh, Jia Jian; Tepel, Fabian-Phillipp; Terada, Susumu; Terashi, Koji; Terron, Juan; Terzo, Stefano; Testa, Marianna; Teuscher, Richard; Theveneaux-Pelzer, Timothée; Thomas, Juergen; Thomas-Wilsker, Joshuha; Thompson, Paul; Thompson, Stan; Thomsen, Lotte Ansgaard; Thomson, Evelyn; Tibbetts, Mark James; Ticse Torres, Royer Edson; Tikhomirov, Vladimir; Tikhonov, Yury; Timoshenko, Sergey; Tipton, Paul; Tisserant, Sylvain; Todome, Kazuki; Todorova-Nova, Sharka; Tojo, Junji; Tokár, Stanislav; Tokushuku, Katsuo; Tolley, Emma; Tomlinson, Lee; Tomoto, Makoto; Tompkins, Lauren; Toms, Konstantin; Tong, Baojia(Tony); Tornambe, Peter; Torrence, Eric; Torres, Heberth; Torró Pastor, Emma; Toth, Jozsef; Touchard, Francois; Tovey, Daniel; Treado, Colleen Jennifer; Trefzger, Thomas; Tricoli, Alessandro; Trigger, Isabel Marian; Trincaz-Duvoid, Sophie; Tripiana, Martin; Trischuk, William; Trocmé, Benjamin; Trofymov, Artur; Troncon, Clara; Trottier-McDonald, Michel; Trovatelli, Monica; Truong, Loan; Trzebinski, Maciej; Trzupek, Adam; Tsang, Ka Wa; Tseng, Jeffrey; Tsiareshka, Pavel; Tsipolitis, Georgios; Tsirintanis, Nikolaos; Tsiskaridze, Shota; Tsiskaridze, Vakhtang; Tskhadadze, Edisher; Tsui, Ka Ming; Tsukerman, Ilya; Tsulaia, Vakhtang; Tsuno, Soshi; Tsybychev, Dmitri; Tu, Yanjun; Tudorache, Alexandra; Tudorache, Valentina; Tulbure, Traian Tiberiu; Tuna, Alexander Naip; Tupputi, Salvatore; Turchikhin, Semen; Turgeman, Daniel; Turk Cakir, Ilkay; Turra, Ruggero; Tuts, Michael; Ucchielli, Giulia; Ueda, Ikuo; Ughetto, Michael; Ukegawa, Fumihiko; Unal, Guillaume; Undrus, Alexander; Unel, Gokhan; Ungaro, Francesca; Unno, Yoshinobu; Unverdorben, Christopher; Urban, Jozef; Urquijo, Phillip; Urrejola, Pedro; Usai, Giulio; Usui, Junya; Vacavant, Laurent; Vacek, Vaclav; Vachon, Brigitte; Valderanis, Chrysostomos; Valdes Santurio, Eduardo; Valencic, Nika; Valentinetti, Sara; Valero, Alberto; Valéry, Lo\\"ic; Valkar, Stefan; Vallier, Alexis; Valls Ferrer, Juan Antonio; Van Den Wollenberg, Wouter; van der Graaf, Harry; van Eldik, Niels; van Gemmeren, Peter; Van Nieuwkoop, Jacobus; van Vulpen, Ivo; van Woerden, Marius Cornelis; Vanadia, Marco; Vandelli, Wainer; Vanguri, Rami; Vaniachine, Alexandre; Vankov, Peter; Vardanyan, Gagik; Vari, Riccardo; Varnes, Erich; Varni, Carlo; Varol, Tulin; Varouchas, Dimitris; Vartapetian, Armen; Varvell, Kevin; Vasquez, Jared Gregory; Vasquez, Gerardo; Vazeille, Francois; Vazquez Schroeder, Tamara; Veatch, Jason; Veeraraghavan, Venkatesh; Veloce, Laurelle Maria; Veloso, Filipe; Veneziano, Stefano; Ventura, Andrea; Venturi, Manuela; Venturi, Nicola; Venturini, Alessio; Vercesi, Valerio; Verducci, Monica; Verkerke, Wouter; Vermeulen, Jos; Vetterli, Michel; Viaux Maira, Nicolas; Viazlo, Oleksandr; Vichou, Irene; Vickey, Trevor; Vickey Boeriu, Oana Elena; Viehhauser, Georg; Viel, Simon; Vigani, Luigi; Villa, Mauro; Villaplana Perez, Miguel; Vilucchi, Elisabetta; Vincter, Manuella; Vinogradov, Vladimir; Vishwakarma, Akanksha; Vittori, Camilla; Vivarelli, Iacopo; Vlachos, Sotirios; Vlasak, Michal; Vogel, Marcelo; Vokac, Petr; Volpi, Guido; Volpi, Matteo; von der Schmitt, Hans; von Toerne, Eckhard; Vorobel, Vit; Vorobev, Konstantin; Vos, Marcel; Voss, Rudiger; Vossebeld, Joost; Vranjes, Nenad; Vranjes Milosavljevic, Marija; Vrba, Vaclav; Vreeswijk, Marcel; Vuillermet, Raphael; Vukotic, Ilija; Wagner, Peter; Wagner, Wolfgang; Wahlberg, Hernan; Wahrmund, Sebastian; Wakabayashi, Jun; Walder, James; Walker, Rodney; Walkowiak, Wolfgang; Wallangen, Veronica; Wang, Chao; Wang, Chao; Wang, Fuquan; Wang, Haichen; Wang, Hulin; Wang, Jike; Wang, Jin; Wang, Qing; Wang, Rui; Wang, Song-Ming; Wang, Tingting; Wang, Wei; Wang, Wenxiao; Wang, Zirui; Wanotayaroj, Chaowaroj; Warburton, Andreas; Ward, Patricia; Wardrope, David Robert; Washbrook, Andrew; Watkins, Peter; Watson, Alan; Watson, Miriam; Watts, Gordon; Watts, Stephen; Waugh, Ben; Webb, Aaron Foley; Webb, Samuel; Weber, Michele; Weber, Stefan Wolf; Weber, Stephen; Webster, Jordan S; Weidberg, Anthony; Weinert, Benjamin; Weingarten, Jens; Weiser, Christian; Weits, Hartger; Wells, Phillippa; Wenaus, Torre; Wengler, Thorsten; Wenig, Siegfried; Wermes, Norbert; Werner, Michael David; Werner, Per; Wessels, Martin; Whalen, Kathleen; Whallon, Nikola Lazar; Wharton, Andrew Mark; White, Andrew; White, Martin; White, Ryan; Whiteson, Daniel; Wickens, Fred; Wiedenmann, Werner; Wielers, Monika; Wiglesworth, Craig; Wiik-Fuchs, Liv Antje Mari; Wildauer, Andreas; Wilk, Fabian; Wilkens, Henric George; Williams, Hugh; Williams, Sarah; Willis, Christopher; Willocq, Stephane; Wilson, John; Wingerter-Seez, Isabelle; Winklmeier, Frank; Winston, Oliver James; Winter, Benedict Tobias; Wittgen, Matthias; Wobisch, Markus; Wolf, Tim Michael Heinz; Wolff, Robert; Wolter, Marcin Wladyslaw; Wolters, Helmut; Worm, Steven; Wosiek, Barbara; Wotschack, Jorg; Woudstra, Martin; Wozniak, Krzysztof; Wu, Miles; Wu, Sau Lan; Wu, Xin; Wu, Yusheng; Wyatt, Terry Richard; Wynne, Benjamin; Xella, Stefania; Xi, Zhaoxu; Xia, Ligang; Xu, Da; Xu, Lailin; Yabsley, Bruce; Yacoob, Sahal; Yamaguchi, Daiki; Yamaguchi, Yohei; Yamamoto, Akira; Yamamoto, Shimpei; Yamanaka, Takashi; Yamauchi, Katsuya; Yamazaki, Yuji; Yan, Zhen; Yang, Haijun; Yang, Hongtao; Yang, Yi; Yang, Zongchang; Yao, Weiming; Yap, Yee Chinn; Yasu, Yoshiji; Yatsenko, Elena; Yau Wong, Kaven Henry; Ye, Jingbo; Ye, Shuwei; Yeletskikh, Ivan; Yigitbasi, Efe; Yildirim, Eda; Yorita, Kohei; Yoshihara, Keisuke; Young, Charles; Young, Christopher John; Youssef, Saul; Yu, David Ren-Hwa; Yu, Jaehoon; Yu, Jie; Yuan, Li; Yuen, Stephanie P; Yusuff, Imran; Zabinski, Bartlomiej; Zacharis, Georgios; Zaidan, Remi; Zaitsev, Alexander; Zakharchuk, Nataliia; Zalieckas, Justas; Zaman, Aungshuman; Zambito, Stefano; Zanzi, Daniele; Zeitnitz, Christian; Zeman, Martin; Zemla, Andrzej; Zeng, Jian Cong; Zeng, Qi; Zenin, Oleg; Ženiš, Tibor; Zerwas, Dirk; Zhang, Dongliang; Zhang, Fangzhou; Zhang, Guangyi; Zhang, Huijun; Zhang, Jinlong; Zhang, Lei; Zhang, Liqing; Zhang, Matt; Zhang, Rui; Zhang, Ruiqi; Zhang, Xueyao; Zhang, Yu; Zhang, Zhiqing; Zhao, Xiandong; Zhao, Yongke; Zhao, Zhengguo; Zhemchugov, Alexey; Zhong, Jiahang; Zhou, Bing; Zhou, Chen; Zhou, Li; Zhou, Maosen; Zhou, Mingliang; Zhou, Ning; Zhu, Cheng Guang; Zhu, Hongbo; Zhu, Junjie; Zhu, Yingchun; Zhuang, Xuai; Zhukov, Konstantin; Zibell, Andre; Zieminska, Daria; Zimine, Nikolai; Zimmermann, Christoph; Zimmermann, Stephanie; Zinonos, Zinonas; Zinser, Markus; Ziolkowski, Michael; Živković, Lidija; Zobernig, Georg; Zoccoli, Antonio; Zou, Rui; zur Nedden, Martin; Zwalinski, Lukasz
2017-08-14
Light-by-light scattering ($\\gamma\\gamma\\rightarrow\\gamma\\gamma$) is a quantum-mechanical process that is forbidden in the classical theory of electrodynamics. This reaction is accessible at the Large Hadron Collider thanks to the large electromagnetic field strengths generated by ultra-relativistic colliding lead (Pb) ions. Using 480 $\\mu$b$^{-1}$ of Pb+Pb collision data recorded at a centre-of-mass energy per nucleon pair of 5.02 TeV by the ATLAS detector, the ATLAS Collaboration reports evidence for the $\\gamma\\gamma\\rightarrow\\gamma\\gamma$ reaction. A total of 13 candidate events are observed with an expected background of $2.6\\pm0.7$ events. After background subtraction and analysis corrections, the fiducial cross section of the process $\\textrm{Pb+Pb}\\,(\\gamma\\gamma)\\rightarrow \\textrm{Pb}^{(\\ast)}\\textrm{+}\\textrm{Pb}^{(\\ast)}\\,\\gamma\\gamma$, for photon transverse energy $E_{\\mathrm{T}}>3$ GeV, photon absolute pseudorapidity $|\\eta|<2.4$, diphoton invariant mass greater than 6 GeV, diphoton transver...
CMS Collaboration
2018-01-01
A measurement of light-by-light scattering, $\\gamma\\gamma\\to\\gamma\\gamma$, in ultraperipheral PbPb collisions at a centre-of-mass energy per nucleon pair of 5.02 TeV is reported. The analysis is conducted using a data sample corresponding to an integrated luminosity of $390~\\mu\\mathrm{b}^{-1}$ recorded by the CMS experiment at the LHC. Light-by-light scattering processes are selected in events with two photons exclusively produced, each with transverse energy $\\mathrm{E}_{\\mathrm{T}}^{\\gamma}>2~\\mathrm{GeV}$, pseudorapidity $|\\eta^{\\gamma}|5~\\mathrm{GeV}$, diphoton transverse momentum $\\mathrm{p}_{\\mathrm{T}}^{\\gamma\\gamma}<1~\\mathrm{GeV}$, and diphoton acoplanarity below 0.01. After all selection criteria are applied, 14 events are observed, compared to expectations of $11.1 \\pm 1.1$ (th) events for the signal and $3.8 \\pm 1.3$ (stat) for the background processes. The significance of the light-by-light signal against the background-only hypothesis is 4.1 standard deviations. The measured fiducial light-by...
International Nuclear Information System (INIS)
Johnson, R.C.
1980-01-01
High energy and small momentum transfer 2 'yields' 2 hadronic scattering processes are described in the physical framework of particle exchange. Particle production in high energy collisions is considered with emphasis on the features of inclusive reactions though with some remarks on exclusive processes. (U.K.)
Hadron scattering, resonances, and QCD
Briceño, R. A.
2016-11-01
The non-perturbative nature of quantum chromodynamics (QCD) has historically left a gap in our understanding of the connection between the fundamental theory of the strong interactions and the rich structure of experimentally observed phenomena. For the simplest properties of stable hadrons, this is now circumvented with the use of lattice QCD (LQCD). In this talk I discuss a path towards a rigorous determination of few-hadron observables from LQCD. I illustrate the power of the methodology by presenting recently determined scattering amplitudes in the light-meson sector and their resonance content.
High energy hadron-nucleus scattering
International Nuclear Information System (INIS)
Koplik, J.; Mueller, A.H.
1975-01-01
Theoretical expectations for hadron-nucleus scattering at high energy if the basic hadron-hadron interaction is due to Regge poles and cuts arising in multiperipheral or soft field theory models are described. Experiments at Fermilab may provide a critical test of such models
Sum rules for quasifree scattering of hadrons
Peterson, R. J.
2018-02-01
The areas d σ /d Ω of fitted quasifree scattering peaks from bound nucleons for continuum hadron-nucleus spectra measuring d2σ /d Ω d ω are converted to sum rules akin to the Coulomb sums familiar from continuum electron scattering spectra from nuclear charge. Hadronic spectra with or without charge exchange of the beam are considered. These sums are compared to the simple expectations of a nonrelativistic Fermi gas, including a Pauli blocking factor. For scattering without charge exchange, the hadronic sums are below this expectation, as also observed with Coulomb sums. For charge exchange spectra, the sums are near or above the simple expectation, with larger uncertainties. The strong role of hadron-nucleon in-medium total cross sections is noted from use of the Glauber model.
Ericson fluctuations in hadron scattering
International Nuclear Information System (INIS)
Frautschi, S.
1975-01-01
It is shown that there are resonances with high mass and long lives, at the very least, longer than the 10 -23 second transit time across a hadron. The theoretical and then the experimental approaches to this problem are described
Coulomb interference and bending slope in hadron-hadron scattering
International Nuclear Information System (INIS)
Pereira, Flavio I.; Ferreira, Erasmo
1994-01-01
With the purpose of testing the results of QCD calculations on the structure of the forward elastic scattering cross-section, we analyse the coulombic-nuclear interference occurring at small values of the momentum transfer. We emphasize the influence of the hadronic structures on the determination of the Coulomb phase and consequently on the t-dependence of the strong interaction slope parameter. (author)
High energy elastic hadron scattering
International Nuclear Information System (INIS)
Fearnly, T.A.
1986-04-01
The paper deals with the WA7 experiment at the CERN super proton synchrotron (SPS). The elastic differential cross sections of pion-proton, kaon-proton, antiproton-proton, and proton-proton at lower SPS energies over a wide range of momentum transfer were measured. Some theoretical models in the light of the experimental results are reviewed, and a comprehensive impact parameter analysis of antiproton-proton elastic scattering over a wide energy range is presented. A nucleon valence core model for high energy proton-proton and antiproton-proton elastic scattering is described
Medium energy hadron scattering from nuclei
International Nuclear Information System (INIS)
Ginocchio, J.N.; Wenes, G.
1986-01-01
The Glauber approximation for medium energy scattering of hadronic projectiles from nuclei is combined with the interacting boson model of nuclei to produce a transition matrix for elastic and inelastic scattering in algebraic form which includes coupling to all the intermediate states. We present closed form analytic expresions for the transition matrix elements for the three dynamical symmetries of the interacting boson model; that is for, a spherical quadrupole vibrator, a γ unstable rotor, and both prolate and oblate axially symmetric rotors. We give examples of application of this formalism to proton scattering from 154 Sm and 154 Gd. 27 refs., 5 figs., 1 tab
Theoretical aspects of lepton-hadron scattering
International Nuclear Information System (INIS)
Drell, S.D.
1992-01-01
In this paper, I will emphasize two points on Theoretical Aspects of Lepton-Hadron Scattering: (1) The crucial importance of testing the ''exact'' sum rules as tests of the local current algebra. Discrepancies, if found, between experiment and theory cannot be ''interpreted away'' in terms of more complex parton wave functions for the hadronic ground state. The three sum rules of interest are those of Adler, Bjorken, and Gross and Llewellyn-Smith. (2) An understanding of the corrections to scaling in QCD and what they teach us
Hadron production in high energy muon scattering
International Nuclear Information System (INIS)
Hicks, R.G.
1978-01-01
An experiment was performed to study muon-proton scattering at an incident energy of 225 GeV and a total effective flux of 4.3 x 10 10 muons. This experiment is able to detect charged particles in coincidence with the scattered muon in the forward hemisphere, and results are reported for the neutral strange particles K/sub s/ 0 and Λ 0 decaying into two charged particles. Within experimental limits the masses and lifetimes of these particles are consistent with previous measurements. The distribution of hadrons produced in muon scattering was determined, measuring momentum components parallel and transverse to the virtual photon direction, and these distributions are compared to other high energy experiments involving the scattering of pions, protons, and neutrinos from protons. Structure functions for hadron production and particle ratios are calculated. No azimuthal dependence is observed, and lambda production does not appear to be polarized. The physical significance of the results is discussed within the frame-work of the quark-proton model
Hadron production in high energy muon scattering
International Nuclear Information System (INIS)
Hicks, R.G.
1978-01-01
An experiment was performed to study muon-proton scattering at an incident energy of 225 GeV and a total effective flux of 4.3 x 10 10 muons. This experiment is able to detect charged particles in coincidence with the scattered muon in the forward hemisphere, and results are reported for the neutral strange particles K/sub s/ 0 and Λ 0 decaying into two charged particles. Within experimental limits the masses and lifetimes of these particles are consistent with previous measurements. The distribution of hadrons produced in muon scattering is determined, measuring momentum components parallel and transverse to the virtual photon direction, and these distributions are compared to other high energy experiments involving the scattering of pions, protons, and neutrinos from protons. Structure functions for hadron production and particle ratios are calculated. No azimuthal dependence is observed, and lambda production does not appear to be polarized. The physical significance of the results is discussed within the framework of the quark-parton model. 29 references
Hadron scattering in an asymmetric box
International Nuclear Information System (INIS)
Li Xin; Chen Ying; Meng Guozhan; Feng Xu; Gong Ming; He Song; Li Gang; Liu Chuan; Liu Yubin; Ma Jianping; Meng Xiangfei; Shen Yan; Zhang Jianbo
2007-01-01
We propose to study hadron-hadron scattering using lattice QCD in an asymmetric box which allows one to access more non-degenerate low-momentum modes for a given volume. The conventional Luescher's formula applicable in a symmetric box is modified accordingly. To illustrate the feasibility of this approach, pion-pion elastic scattering phase shifts in the I = 2, J = 0 channel are calculated within quenched approximation using improved gauge and Wilson fermion actions on anisotropic lattices in an asymmetric box. After the chiral and continuum extrapolation, we find that our quenched results for the scattering phase shifts in this channel are consistent with the experimental data when the three-momentum of the pion is below 300MeV. Agreement is also found when compared with previous theoretical results from lattice and other means. Moreover, with the usage of asymmetric volume, we are able to compute the scattering phases in the low-momentum range (pion three momentum less than about 350MeV in the center of mass frame) for over a dozen values of the pion three-momenta, much more than using the conventional symmetric box with comparable volume
Quark-Hadron Duality in Electron Scattering
Energy Technology Data Exchange (ETDEWEB)
Wally Melnitchouk; Rolf Ent; Cynthia Keppel
2004-08-01
The duality between partonic and hadronic descriptions of physical phenomena is one of the most remarkable features of strong interaction physics. A classic example of this is in electron-nucleon scattering, in which low-energy cross sections, when averaged over appropriate energy intervals, are found to exhibit the scaling behavior expected from perturbative QCD. We present a comprehensive review of data on structure functions in the resonance region, from which the global and local aspects of duality are quantified, including its flavor, spin and nuclear medium dependence. To interpret the experimental findings, we discuss various theoretical approaches which have been developed to understand the microscopic origins of quark-hadron duality in QCD. Examples from other reactions are used to place duality in a broader context, and future experimental and theoretical challenges are identified.
Hadron elastic scattering at small angles
2002-01-01
This experiment is an extension of the measurements of the WA9 experiment up to the highest energies available in the North Area. It will measure the differential cross-section for hadron elastic scattering in the t-range 0.002-0.05 (GeV/c)$^{2}$ using an ionization chamber for the measurement of the energy and the angle of the recoil and a magnet-WC spectrometer to measure the momentum and direction of the forward particle. From these measurements will be obtained the ratio $\\rho$ of the real to imaginary parts of the forward elastic amplitude and the exponential slope parameter b of the hadronic amplitude at small t. The precision expected in these measurements is $\\Delta \\rho \\approx \\pm 0.01$ and $\\Delta$b $\\approx \\pm 0.2$ (GeV/c)$^{-2}$. \\\\ \\\\ The experimental programme includes: \\\\\\\\ i) measurements of $\\rho$ and b for $\\pi$p elastic scattering at incident momenta between 150 GeV/c and 300 GeV/c; \\\\ ii) measurements of $\\rho$ and b for $\\pi^{+}$p and pp elastic scattering at incident momenta between 5...
Lepton-hadron scattering past and future
CERN. Geneva. Audiovisual Unit
1985-01-01
Lepton-hadron scattering experiments have played a key role in the development and verification of the Standard Model. The lectures will summarize the main ideas and experimental results concerning the substructure of the nucleon, the structure of the weak currents and the production of new particles. In a second step it will be discussed how experiments at e-p colliders like HERA can lead beyond the Standard Model by studying the substructure of quarks and leptons, the existence of new kinds of interaction and/or new particles.
Elastic hadron scattering and optical theorem
Lokajicek, Milos V.; Prochazka, Jiri
2014-01-01
In principle all contemporary phenomenological models of elastic hadronic scattering have been based on the assumption of optical theorem validity that has been overtaken from optics. It will be shown that the given theorem which has not been actually proved cannot be applied to short-ranged strong interactions in any case. The actual progress in description of collision processes might then exist only if the initial states are specified on the basis of impact parameter values of colliding particles and probability dependence on this parameter is established.
Evolution of hadron beams under intrabeam scattering
International Nuclear Information System (INIS)
Wei, Jie.
1993-01-01
Based on assumptions applicable to many circular accelerators, we simplify into analytical form the growth rates of a hadron beam under Coulomb intrabeam scattering (IBS). Because of the dispersion that correlates the horizontal closed orbit to the momentum, the scaling behavior of the growth rates are drastically different at energies low and high compared with the transition energy. At high energies the rates are approximately independent of the energy. Asymptotically, the horizontal and longitudinal beam amplitudes are linearly related by the average dispersion. At low energies, the beam evolves such that the velocity distribution in the rest frame becomes isotropic in all the directions
Gluon exchange in elastic hadron scattering
International Nuclear Information System (INIS)
Jenkovszky, L.L.; Paccanoni, F.; Chikovani, Z.E.
1991-01-01
It is generally accepted that the Pomeron, which determines the long-range component of the strong interaction, corresponds to exchange of gluons with the corresponding quantum numbers (the minimum number of such gluons is two). The C-odd partner of the Pomeron, the odderon, corresponds to exchange of an odd number of gluons (three or more). By means of a model of the nonperturbative gluon propagator, restrictions are obtained on the parameters of two-gluon (Pomeron) and three-gluon (odderon) exchange in hadron scattering. In the framework of this model an interpretation is proposed for the various asymptotic regimes in the behavior of the total cross section and of the differential cross section of elastic scattering at high energies
Hadronic parity violation and inelastic electron-deuteron scattering
International Nuclear Information System (INIS)
Liu, C.-P.; Prezeau, G.; Ramsey-Musolf, M.J.
2003-01-01
We compute contributions to the parity-violating (PV) inelastic electron-deuteron scattering asymmetry arising from hadronic PV. While hadronic PV effects can be relatively important in PV threshold electrodisintegration, we find that they are highly suppressed at quasielastic kinematics. The interpretation of the PV quasielastic asymmetry is, thus, largely unaffected by hadronic PV
Factorization for short distance hadron-hadron scattering
International Nuclear Information System (INIS)
Collins, J.C.; Illinois Inst. of Tech., Chicago; Soper, D.E.; Sterman, G.
1985-01-01
We show that factorization holds at leading twist in the Drell-Yang cross section dsigma/dQ 2 dy and related inclusive hadron-hadron cross sections. We review the heuristic arguments for factorization, as well as the difficulties which must be overcome in a proof. We go on to give detailed arguments for the all order cancellation of soft gluons, and to show how this leads to factorization. (orig.)
Gluon bremstrahlung effects in large P/sub perpendicular/ hadron-hadron scattering
International Nuclear Information System (INIS)
Fox, G.C.; Kelly, R.L.
1982-02-01
We consider effects of parton (primarily gluon) bremstrahlung in the initial and final states of high transverse momentum hadron-hadron scattering. Monte Carlo calculations based on conventional QCD parton branching and scattering processes are presented. The calculations are carried only to the parton level in the final state. We apply the model to the Drell-Yan process and to high transverse momentum hadron-hadron scattering triggered with a large aperture calorimeter. We show that the latter triggers are biased in that they select events with unusually large bremstrahlung effects. We suggest that this trigger bias explains the large cross section and non-coplanar events observed in the NA5 experiment at the SPS
Hadronization in deep inelastic scattering at HERMES
International Nuclear Information System (INIS)
Muccifora, V
2004-01-01
Recent results from HERMES in the hadron leptoproduction of nuclei are presented. The possible interpretations in terms of medium modifications of the parton fragmentation function and the implications on the parton energy loss are discussed
Evidence of Light-by-Light Scattering with Real Photons
Energy Technology Data Exchange (ETDEWEB)
Boege, J.
2003-12-19
In a new experiment at the Stanford Linear Accelerator Center, heretofore untested aspects of high field strength Quantum Electrodynamics were probed. Bunches of 46.6 GeV electrons available in the Final Focus Test Beam line were brought into collision with terawatt pulses of either 1.17 eV or 2.34 eV photons from a Nd:Glass laser system. Several physical process were investigated. This thesis describes the production of electron-positron pairs in photon-photon collisions. This is particularly interesting since it represents the generation of massive particles from massless particles. The bunch/pulse trajectories are approximately antiparallel. Due to the head-on nature of the collisions, the electrons see, in their rest frame, a transformed laser pulse electric field amplitude {bar {var_epsilon}}{sub 0} = 2{gamma}{var_epsilon}{sub 0}, and so a lab frame field {var_epsilon} {approx} 1.0 x 10{sup 11} V/cm corresponds to a 46.6 GeV electron rest frame field {bar {var_epsilon}}{sub 0} {approx} 1.8 x 10{sup 16} V/cm. For electric field amplitudes of this magnitude, perturbative QED is of limited validity. Multiphoton processes dominate collision results. The geometry of the experiments was such that any pairs produced came into existence in the midst of the electron/photon collision region. The electron from a produced pair was indistinguishable from the recoil electrons generated via other processes in collisions. Detecting the positron, then, was the only way to observe pair production. In data accumulated during the September 1994 Final Focus Test Beam run, positrons in excess of background were detected. Positron signals were extracted from an ensemble of data collected during electron bunch/laser pulse collisions. Calorimeter readings were used to measure the energy, and reconstruct the transverse displacement of positrons propagating downstream from the bunch/pulse collision region. Field maps of permanent magnets located downstream of the collision region but upstream of the calorimeter were used in implementing a cut of off-momentum background positrons. Effects of various cuts and the characteristics of the detected positrons are presented. Statistically significant positron production above background is reported. The rate for e{sup +} production is calculated, and the energy spectrum of the candidates is shown. The agreement of simulation results with these observations is described.
Lepton-hadron scattering: past, present and future
International Nuclear Information System (INIS)
Saxon, D.H.
1985-09-01
The paper reviews the principal phenomena in lepton-hadron scattering. The subject is discussed under the topic headings: search for substructure in the nucleon; deep inelastic scattering; the role of gluons; partons in nuclei and the EMC effect; weak neutral currents; and future prospects. (UK)
International Nuclear Information System (INIS)
Hansl-Kozanecka, T.
1992-01-01
In this set of lectures the author examines phenomenological aspects of quantum chromodynamics (QCD) which are relevant for lepton-hadron, electron-positron, and hadron-hadron collisions. He points how the strength of the strong coupling constant, αs, makes QCD calculations converge much more slowly in powers of αs, and missing higher order terms must be carefully estimated. The most stringent test of QCD can be performed in deep inelastic lepton scattering and in e + e - annihilation. In deep inelastic scattering the virtual γ or W/Z are used as a probe of the nucleon structure. They couple to quarks, not gluons. Only the incoming and outgoing lepton have to be measured. The hadronic fluid state does not have to be analyzed. In e + e - annihilation the virtual γ or Z 0 decays to lepton and quark pairs. The branching ratio into quarks is a counter for the number of colours available, the detailed structure of the final state reflects the radiation of gluons as the initial quark-antiquark separate from each other. Quarks and gluons are observed here, though in the presence of hadron formation. Hard hadron-hadron, or parton-parton collisions provide cross sections dominated by the gluon component, which is only weakly measured in deep inelastic collisions. Recent experimental results in these three areas are reviewed, and compared to QCD calculations. Scaling violations and analysis of structure functions in deep inelastic scattering are reviewed. QCD in e + e - branching to hadrons is reviewed near the Z 0 resonance, and a number of cross sections and jet related properties which can be calculated as a function of the single parameter αs are reviewed. Hadron-hadron collisions are reviewed for three processes; jet production, direct photon production, and high p perpendicular W/Z boson production
Gluon bremsstrahlung and elastic scattering of hadrons
International Nuclear Information System (INIS)
Povh, B.
2001-01-01
The differential and the total cross sections in high energy hadron-proton interactions give a beautiful insight in the low Q 2 structure of the nucleon. The cross section is composed of two parts: a large energy independent part corresponding to the interaction of the valence quark with the target without gluon radiation and an energy dependent part caused by gluon bremsstrahlung. The gluons are located at small transverse distances of about 0.3 fm from the valence quarks. The model with two scales, the size of the hadron (R 2 ∼ 1 fm 2 ) and the size of the gluonic cloud (r 0 2 ∼ 0.1 fm 2 ), correctly predicts the total and the differential cross sections and the behaviour of diffractive dissociation in hadronic and deep inelastic events. (orig.)
Hadron mass corrections in semi-inclusive deep inelastic scattering
International Nuclear Information System (INIS)
Accardi, A.; Hobbs, T.; Melnitchouk, W.
2009-01-01
We derive mass corrections for semi-inclusive deep inelastic scattering of leptons from nucleons using a collinear factorization framework which incorporates the initial state mass of the target nucleon and the final state mass of the produced hadron h. The hadron mass correction is made by introducing a generalized, finite-Q 2 scaling variable ζ h for the hadron fragmentation function, which approaches the usual energy fraction z h = E h /ν in the Bjorken limit. We systematically examine the kinematic dependencies of the mass corrections to semi-inclusive cross sections, and find that these are even larger than for inclusive structure functions. The hadron mass corrections compete with the experimental uncertainties at kinematics typical of current facilities, Q 2 2 and intermediate x B > 0.3, and will be important to efforts at extracting parton distributions from semi-inclusive processes at intermediate energies.
Forward gluon production in hadron-hadron scattering with Pomeron loops
International Nuclear Information System (INIS)
Iancu, E.
2006-01-01
We discuss new physical phenomena expected in particle production in hadron-hadron collisions at high energy, as a consequence of Pomerons loop effects in the evolution equations for the Color Glass Condensate. We focus on gluon production in asymmetric, 'dilute-dense', collisions: a dilute projectile scatters off a dense hadronic target, whose gluon distribution is highly evolved. This situation is representative for particle production in proton-proton collisions at forward rapidities (say, at LHC) and admits a dipole factorization similar to that of deep inelastic scattering (DIS). We show that at sufficiently large forward rapidities, where the Pomerons loop effects become important in the evolution of the target wavefunction, gluon production is dominated by 'black spots' (saturated gluon configurations) up to very large values of the transverse momentum, well above the average saturation momentum in the target. In this regime, the produced gluon spectrum exhibits diffusive scaling, so like DIS at sufficiently high energy. (authors)
HADRONIC SCATTERING IN THE COLOR GLASS CONDENSATE.
Energy Technology Data Exchange (ETDEWEB)
VENUGOPALAN, R.
2005-05-15
Multi-particle production in QCD is dominated by higher twist contributions. The operator product expansion is not very effective here because the number of relevant operators grow rapidly with increasing twist. The Color Glass Condensate (CGC) provides a framework in QCD to systematically discuss ''classical'' (multiple scattering) and ''quantum'' evolution (shadowing) effects in multi-particle production. The apparently insuperable problem of nucleus-nucleus scattering in QCD simplifies greatly in the CGC. A few examples are discussed with emphasis on open problems.
Hadronic scattering in the color glass condensate
Energy Technology Data Exchange (ETDEWEB)
Venugopalan, R. [Brookhaven National Lab., Physics Department, Upton, NY (United States)
2005-07-01
Multi-particle production in QCD is dominated by higher twist contributions. The operator product expansion is not very effective here because the number of relevant operators grow rapidly with increasing twist. The color glass condensate (CGC) provides a framework in QCD to systematically discuss 'classical' (multiple scattering) and 'quantum' evolution (shadowing) effects in multi-particle production. The apparently insuperable problem of nucleus-nucleus scattering in QCD simplifies greatly in the CGC. A few examples are discussed with emphasis on open problems. (author)
Jet analysis in lepton-hadron scattering from QCD
International Nuclear Information System (INIS)
Ranft, J.; Ranft, G.
1978-10-01
For deep inelastic lepton-hadron scattering the cross sections dσ/dT and dσ/dS are deduced from QCD perturbation theory in terms of the collective jet variables thrust T and spherocity S. It is found that the shape of these cross sections depends mainly on the total hadronic energy W. While present data are consistent with the cross sections calculated they do not yet prove or disprove the presence of three-jet contributions. It is predicted that these contributions will be clearly visible for W greater than approximately 12 to 15 GeV. (author)
Transverse energy distribution and hard constituent scattering in hadronic collisions
Directory of Open Access Journals (Sweden)
Torsten Åkesson
1983-01-01
Full Text Available We estimate the contributions to the total transverse energy spectrum from hard constituent scattering and the soft hadronic spectrum in hadron collisions. The transverse energy at which jet production starts to dominate is found to be essentially independent of the cms-energy (for large enough s and roughly a linear function of rapidity and azimuthal angle interval included. Calculations are presented for pp collisions at s= 25and60GeV, andp¯p interactions at s= 540GeV.
On model-independent analyses of elastic hadron scattering
International Nuclear Information System (INIS)
Avila, R.F.; Campos, S.D.; Menon, M.J.; Montanha, J.
2007-01-01
By means of an almost model-independent parametrization for the elastic hadron-hadron amplitude, as a function of the energy and the momentum transfer, we obtain good descriptions of the physical quantities that characterize elastic proton-proton and antiproton-proton scattering (total cross section, r parameter and differential cross section). The parametrization is inferred on empirical grounds and selected according to high energy theorems and limits from axiomatic quantum field theory. Based on the predictive character of the approach we present predictions for the above physical quantities at the Brookhaven RHIC, Fermilab Tevatron and CERN LHC energies. (author)
Analytic amplitudes for hadronic forward scattering: COMPETE update
Energy Technology Data Exchange (ETDEWEB)
Nicolescu, B.; Cudell, J.R.; Ezhela, V.V.; Gauron, P.; Kang, K.; Kuyanov, Yu.V.; Lugovsky, S.B.; Martynov, E.; Razuvaev, E.A.; Tkachenko, N.P
2003-04-01
We consider several classes of analytic parametrizations of hadronic scattering amplitudes, and compare their predictions to all available forward data (pp, p-bar p, {pi}p, Kp, {gamma}p, {gamma}{gamma}, {sigma}p). Although these parametrizations are very close for {radical}s {>=} 9 GeV, it turns out that they differ markedly at low energy, where a universal Pomeron term {approx} ln{sup 2} s enables one to extend the fit down to {radical}s = 4 GeV. We present predictions on the total cross sections and on the ratio of the real part to the imaginary part of the elastic amplitude ({rho} parameter) for present and future pp and p-bar p colliders, and on the total cross sections for {gamma}p {yields} hadrons at cosmic-ray energies and for {gamma}{gamma} {yields} hadrons up to {radical}s = 1 TeV.
The hadronic final state in deep inelastic scattering at HERA
International Nuclear Information System (INIS)
Lanius, P.
1994-10-01
Global properties of the hadronic final state of deep inelastic scattering events recorded in 1992 with the H1 detector at HERA, are investigated. The data are corrected for detector effects and can be compared directly with QCD phenomenology and calculations based on BFKL dynamics. The measurement of the energy flows in the laboratory frame and in the hadronic centre of mass system reveal large discrepancies between the data and the different model predictions, indicating the failure of models based on Altarelli-Parisi evolution at low χ. However, these energy flow results are found to agree fairly well with theoretical predictions derived from Lipatov (BFKL) evolution. In the hadronic centre of mass frame the longitudinal and transverse momentum components of charged particles are measured. The longitudinal component exhibits scaling with W and allows comparison with lower energy lepton-nucleon scattering data as well as with e + e - data from LEP. For the 1993 data, studies of the charged particle energy spectra in the Breit frame are undertaken. This measurement allows a first tentative look at predictions from the Modified Leading Logarithmic Approximation for the target region, a region that to-date unexplored has been unexplored. (orig.)
Forward gluon production in hadron-hadron scattering with Pomeron loops
Energy Technology Data Exchange (ETDEWEB)
Iancu, E. [CEA Saclay, Service de Physique Th orique (DSM/SPhT), Unite de recherche associ e au CNRS (URA D2306), 91 - Gif-sur-Yvette (France). Direction des Sciences de la Matiere; Marquet, C.; Soyez, G. [CEA Saclay, Service de Physique Th orique (DSM/SPhT), Unite de recherche associ e au CNRS (URA D2306), 91 - Gif-sur-Yvette (France). Direction des Sciences de la Matiere; Liege Univ., Fundamental Theoretical Physics Group (Belgium)
2006-07-01
We discuss new physical phenomena expected in particle production in hadron-hadron collisions at high energy, as a consequence of Pomerons loop effects in the evolution equations for the Color Glass Condensate. We focus on gluon production in asymmetric, 'dilute-dense', collisions: a dilute projectile scatters off a dense hadronic target, whose gluon distribution is highly evolved. This situation is representative for particle production in proton-proton collisions at forward rapidities (say, at LHC) and admits a dipole factorization similar to that of deep inelastic scattering (DIS). We show that at sufficiently large forward rapidities, where the Pomerons loop effects become important in the evolution of the target wavefunction, gluon production is dominated by 'black spots' (saturated gluon configurations) up to very large values of the transverse momentum, well above the average saturation momentum in the target. In this regime, the produced gluon spectrum exhibits diffusive scaling, so like DIS at sufficiently high energy. (authors)
Effects of hadronic colour structure in quasi-elastic and charge-exchange scattering on nuclei
International Nuclear Information System (INIS)
Kopeliovich, B.Z.; Zakharov, B.G.
1986-01-01
Effects of hadronic hidden colour screening are considered in hadron-nucleus interaction. It is shown that in the quasi-free charge exchange-reaction nuclear matter becomes transparent for the scattered hadron if the momentum transfer is large enough. The available experimental data confirm this prediction of QCD
Diffractive production in deep inelastic scattering and hadronic interactions
International Nuclear Information System (INIS)
Kaidalow, A.
1996-01-01
Diffractive processes in hadronic interactions are considered and important role of multi-Pomeron exchanges is emphasized. It is argued that in deep inelastic scattering these contributions are much less important and energy behavior of structure functions at Q 2 ≥ 1 GeV 2 is determined mostly by bare Pomeron intercept. It is shown that the model based on these ideas is in a perfect agreement with recent results from HERA. Diffractive production in DIS is discussed and theoretical predictions for the structure function of the Pomeron are compared with experimental observations. It is emphasized that both quarks and gluons in the Pomeron have hard distributions. Shadowing corrections to structure function of a nucleon are calculated and found to small in the region of x > 10 -4 . A good agreement with experimental data on the shadowing of structure functions of nuclei is obtained. Energy dependence for the cross sections of the diffractive production of vector mesons by real and virtual photons is calculated in the same approach and is found to be in an excellent agreement with experiment. (author)
Space-time aspects of hadronic cascading in lepton nucleus scattering
International Nuclear Information System (INIS)
Gyulassy, M.; Pluemer, M.
1989-05-01
A Monte Carlo model of hadronic cascading in inelastic lepton nucleus scattering is constructed to investigate space-time scenarios consistent with the momentum space description of string models of multiparticle production. The prospects for resolving the ambiguity inherent in the definition of a formation length for composite hadrons are emphasized. 15 refs., 13 figs
Giordano, M.; Meggiolaro, E.; Silva, P. V. R. G.
2017-08-01
In the present investigation we study the leading and subleading high-energy behavior of hadron-hadron total cross sections using a best-fit analysis of hadronic scattering data. The parametrization used for the hadron-hadron total cross sections at high energy is inspired by recent results obtained by Giordano and Meggiolaro [J. High Energy Phys. 03 (2014) 002, 10.1007/JHEP03(2014)002] using a nonperturbative approach in the framework of QCD, and it reads σtot˜B ln2s +C ln s ln ln s . We critically investigate if B and C can be obtained by means of best-fits to data for proton-proton and antiproton-proton scattering, including recent data obtained at the LHC, and also to data for other meson-baryon and baryon-baryon scattering processes. In particular, following the above-mentioned nonperturbative QCD approach, we also consider fits where the parameters B and C are set to B =κ Bth and C =κ Cth, where Bth and Cth are universal quantities related to the QCD stable spectrum, while κ (treated as an extra free parameter) is related to the asymptotic value of the ratio σel/σtot. Different possible scenarios are then considered and compared.
Hadron transverse momentum distributions in muon deep inelastic scattering at 160 GeV/c
Czech Academy of Sciences Publication Activity Database
Adolph, C.; Alekseev, M.; Alexakhin, V. Yu.; Alexandrov, Yu.; Alexeev, G. D.; Amoroso, A.; Andrieux, V.; Austregisilio, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Bedfer, Y.; Berlin, A.; Bernhard, J.; Bertini, R.; Bicker, K.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Büchele, M.; Burtin, E.; Capozza, L.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Crespo, M.; Dalla Torre, S.; Dasgupta, S. S.; Dasgupta, S.; Denisov, O.; Donskov, S.; Doshita, N.; Duic, V.; Dünnweber, W.; Dziewiecki, M.; Efremov, A.V.; Elia, C.; Eversheim, P.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger jr., M.; Fischer, H.; Franco, C.; Fresne von Hohenesche, N.; Friedrich, J.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmüller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Guthörl, T.; Haas, F.; von Harrach, D.; Heinsius, F.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Höppner, Ch.; d'Hose, N.; Huber, S.; Ishimoto, S.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Joosten, R.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.; Khokhlov, Y.; Kisselev, Y.; Klein, F.; Klimaszewski, K.; Koivuniemi, J.; Kolosov, V.; Kondo, K.; Königsmann, K.; Konorov, I.; Konstantinov, V.; Kotzinian, A.; Kouznetsov, O.; Krämer, M.; Kroumchtein, Z.; Kuchinski, N.; Kunne, F.; Kurek, K.; Kurjata, R. P.; Lednev, A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G.; Mann, A.; Marchand, C.; Martin, A.; Marzec, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Y.; Morreale, A.; Nagaytsev, A.; Nagel, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.; Nový, J.; Nowak, W. D.; Nunes, A.S.; Olshevsky, A.; Ostrick, M.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.; Pretz, J.; Quaresma, M.; Quintans, C.; Rajotte, J.; Ramos, S.; Reicherz, G.; Rocco, E.; Rodionov, V. K.; Rondio, E.; Rossiyskaya, N. S.; Ryabchikov, D.; Samoylenko, V.; Sandacz, A.; Sapozhnikov, M.; Sarkar, S.; Savin, I.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schlütter, T.; Schmidt, A.; Schmidt, K.; Schmiden, H.; Schmitt, L.; Schönning, K.; Schopferer, S.; Schott, M.; Shevchenko, O.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Sosio, S.; Sozzi, F.; Srnka, Aleš; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Sznajder, P.; Takekawa, S.; Ter Wolbeek, J.; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Wang, L.; Weisrock, T.; Wilfert, M.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Zhuravlev, N.; Ziembicki, M.
2013-01-01
Roč. 73, č. 8 (2013), 2531:1-15 ISSN 1434-6044 Institutional support: RVO:68081731 Keywords : hadron * inelastic scattering Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 5.436, year: 2013
Electric and magnetic polarizabilities of hadrons via elastic Compton scattering at KAON
International Nuclear Information System (INIS)
Moinester, M.A.; Blecher, M.
1990-08-01
The study of dynamic properties of hadrons presents a challenge. Among the most basic of these are the electric and magnetic polarizabilities describing the electromagnetic structure of hadrons. They characterize the induced transient dipole moments of hadrons in an external electromagnetic field. During gamma-hadron Compton scattering the lowest order scattering is determined by the charge and magnetic moment. The next order scattering is determined by the induced dipole moments. The dipole polarizabilities probe the rigidity of the internal structure of baryons and mesons, the dipole moments being induced by the rearrangement of the hadron constituents driven by the presence of the electric and magnetic fields of the photon during scattering. A sophisticated understanding of hadrons within the framework of QCD will be tested, in part, by the prediction of these quantities. For the light charged pion, chiral symmetry leads to a precise prediction for the polarizabilities. For the heavier charged kaon, chiral perturbation theory can be applied to predict the polarizabilities. For these cases, the experimental polarizabilities subject the underlying chiral symmetry and chiral perturbation techniques of QCD to new and serious tests. Here the physics of electromagnetic polarizabilities is first described, followed by a review of previous experimental and theoretical polarizability results for the proton, neutron, pion, and kaon. A brief description is then given of how polarizabilities for these hadrons can be studied at the proposed TRIUMF KAON facility. (36 refs., 4 figs.)
Alekseev, M G; Alexandrov, Yu; Alexeev, G D; Amoroso, A; Austregesilo, A; Badełek, B; Balestra, F; Barth, J; Baum, G; Bedfer, Y; Bernhard, J; Bertini, R; Bettinelli, M; Birsa, R; Bisplinghoff, J; Bordalo, P; Bradamante, F; Bravar, A; Bressan, A; Brona, G; Burtin, E; Bussa, M P; Chaberny, D; Chiosso, M; Chung, S U; Cicuttin, A; Colantoni, M; Crespo, M L; Dalla Torre, S; Das, S; Dasgupta, S S; Denisov, O Yu; Dhara, L; Diaz, V; Donskov, S V; Doshita, N; Duic, V; Dünnweber, W; Efremov, A; El Alaoui, A; Eversheim, P D; Eyrich, W; Faessler, M; Ferrero, A; Filin, A; Finger, M; Finger, M Jr; Fischer, H; Franco, C; Friedrich, J M; Garfagnini, R; Gautheron, F; Gavrichtchouk, O P; Gazda, R; Gerassimov, S; Geyer, R; Giorgi, M; Gnesi, I; Gobbo, B; Goertz, S; Grabmüller, S; Grasso, A; Grube, B; Gushterski, R; Guskov, A; Haas, F; von Harrach, D; Hasegawa, T; Heinsius, F H; Herrmann, F; Heß, C; Hinterberger, F; Horikawa, N; Höppner, Ch; d’Hose, N; Ilgner, C; Ishimoto, S; Ivanov, O; Ivanshin, Yu; Iwata, T; Jahn, R; Jasinski, P; Jegou, G; Joosten, R; Kabuß, E; Kang, D; Ketzer, B; Khaustov, G V; Khokhlov, Yu A; Kisselev, Yu; Klein, F; Klimaszewski, K; Koblitz, S; Koivuniemi, J H; Kolosov, V N; Kondo, K; Königsmann, K; Konopka, R; Konorov, I; Konstantinov, V F; Korzenev, A; Kotzinian, A M; Kouznetsov, O; Kowalik, K; Krämer, M; Kral, A; Kroumchtein, Z V; Kuhn, R; Kunne, F; Kurek, K; Lauser, L; Le Goff, J M; Lednev, A A; Lehmann, A; Levorato, S; Lichtenstadt, J; Liska, T; Maggiora, A; Maggiora, M; Magnon, A; Mallot, G K; Mann, A; Marchand, C; Martin, A; Marzec, J; Massmann, F; Matsuda, T; Meyer, W; Michigami, T; Mikhailov, Yu V; Moinester, M A; Mutter, A; Nagaytsev, A; Nagel, T; Nassalski, J; Negrini, T; Nerling, F; Neubert, S; Neyret, D; Nikolaenko, V I; Nunes, A S; Olshevsky, A G; Ostrick, M; Padee, A; Panknin, R; Panzieri, D; Parsamyan, B; Paul, S; Pawlukiewicz-Kaminska, B; Perevalova, E; Pesaro, G; Peshekhonov, D V; Piragino, G; Platchkov, S; Pochodzalla, J; Polak, J; Polyakov, V A; Pontecorvo, G; Pretz, J; Quintans, C; Rajotte, J F; Ramos, S; Rapatsky, V; Reicherz, G; Richter, A; Robinet, F; Rocco, E; Rondio, E; Ryabchikov, D I; Samoylenko, V D; Sandacz, A; Santos, H; Sapozhnikov, M G; Sarkar, S; Savin, I A; Sbrizzai, G; Schiavon, P; Schill, C; Schlüter, T; Schmitt, L; Schopferer, S; Schröder, W; Shevchenko, O Yu; Siebert, H W; Silva, L; Sinha, L; Sissakian, A N; Slunecka, M; Smirnov, G I; Sosio, S; Sozzi, F; Srnka, A; Stolarski, M; Sulc, M; Sulej, R; Takekawa, S; Tessaro, S; Tessarotto, F; Teufel, A; Tkatchev, L G; Uhl, S; Uman, I; Virius, M; Vlassov, N V; Vossen, A; Weitzel, Q; Windmolders, R; Wislicki, W; Wollny, H; Zaremba, K; Zavertyaev, M; Zemlyanichkina, E; Ziembicki, M; Zhao, J; Zhuravlev, N; Zvyagin, A
2010-01-01
Azimuthal asymmetries in semi-inclusive production of positive (h^+) and negative hadrons (h^-) have been measured by scattering 160 GeV muons off longitudinally polarised deuterons at CERN. The asymmetries were decomposed in several terms according to their expected modulation in the azimuthal angle phi of the outgoing hadron. Each term receives contributions from one or several spin and transverse-momentum-dependent parton distribution and fragmentation functions. The amplitudes of all phi-modulation terms of the hadron asymmetries integrated over the kinematic variables are found to be consistent with zero within statistical errors, while the constant terms are nonzero and equal for h^+ and h^- within the statistical errors. The dependencies of the phi-modulated terms versus the Bjorken momentum fraction x, the hadron fractional momentum z, and the hadron transverse momentum p_h^T were studied. The x dependence of the constant terms for both positive and negative hadrons is in agreement with the longitudin...
Time reversal odd fragmentation functions in semi-inclusive deep inelastic lepton-hadron scattering
Energy Technology Data Exchange (ETDEWEB)
Mulders, P.J. [National Inst. for Nuclear Physics and High Energy Physics, Amsterdam (Netherlands); Levelt, J. [Univ. of Erlangen-Nuernberg (Germany)
1994-04-01
In semi-inclusive scattering of polarized leptons from unpolarized hadrons, one can measure a time reversal odd structure function. It shows up as a sin({phi}) asymmetry of the produced hadrons. This asymmetry can be expressed as the product of a twist-three {open_quotes}hadron {r_arrow} quark{close_quotes} profile function and a time reversal odd twist-two {open_quotes}quark {r_arrow} hadron{close_quotes} fragmentation function. This fragmentation function can only be measured for nonzero transverse momenta of the produced hadron. Its appearance is a consequence of final state interactions between the produced hadron and the rest of the final state.
International Nuclear Information System (INIS)
Alekseev, M.G.; Colantoni, M.; Maggiora, A.; Alexakhin, V.Yu.; Alexeev, G.D.; Efremov, A.; Finger, M.; Gavrichtchouk, O.P.; Gushterski, R.; Guskov, A.; Ivanov, O.; Ivanshin, Yu.; Kroumchtein, Z.V.; Nagaytsev, A.; Olshevsky, A.G.; Perevalova, E.; Peshekhonov, D.V.; Pontecorvo, G.; Rapatsky, V.; Sapozhnikov, M.G.; Savin, I.A.; Shevchenko, O.Yu.; Sissakian, A.N.; Slunecka, M.; Smirnov, G.I.; Tkatchev, L.G.; Vlassov, N.V.; Zemlyanichkina, E.; Zhuravlev, N.; Alexandrov, Yu.; Zavertyaev, M.; Amoroso, A.; Balestra, F.; Bertini, R.; Bussa, M.P.; Chiosso, M.; Garfagnini, R.; Gnesi, I.; Grasso, A.; Kotzinian, A.M.; Maggiora, M.; Parsamyan, B.; Piragino, G.; Rocco, E.; Sosio, S.; Austregesilo, A.; Badelek, B.; Gazda, R.; Klimaszewski, K.; Kurek, K.; Nassalski, J.; Pawlukiewicz-Kaminska, B.; Rondio, E.; Sandacz, A.; Wislicki, W.; Barth, J.; Klein, F.; Panknin, R.; Pretz, J.; Windmolders, R.; Baum, G.; Bedfer, Y.; Burtin, E.; El Alaoui, A.; Ferrero, A.; Hose, N. d'; Jegou, G.; Kunne, F.; Le Goff, J.M.; Magnon, A.; Marchand, C.; Neyret, D.; Platchkov, S.; Robinet, F.; Bernhard, J.; Chaberny, D.; Harrach, D. von; Jasinski, P.; Kabuss, E.; Koblitz, S.; Korzenev, A.; Ostrick, M.; Pochodzalla, J.; Siebert, H.W.; Bettinelli, M.; Duennweber, W.; Faessler, M.; Geyer, R.; Rajotte, J.F.; Schlueter, T.; Uman, I.; Zvyagin, A.; Birsa, R.; Bravar, A.; Dalla Torre, S.; Gobbo, B.; Tessaro, S.; Tessarotto, F.; Bisplinghoff, J.; Eversheim, P.D.; Hinterberger, F.; Jahn, R.; Joosten, R.; Massmann, F.; Negrini, T.; Bordalo, P.; Franco, C.; Nunes, A.S.; Quintans, C.; Ramos, S.; Santos, H.; Silva, L.; Bradamante, F.; Bressan, A.; Duic, V.; Giorgi, M.; Levorato, S.; Martin, A.; Pesaro, G.; Sbrizzai, G.; Schiavon, P.; Sozzi, F.; Takekawa, S.; Brona, G.; Chung, S.U.; Friedrich, J.M.; Grabmueller, S.; Grube, B.; Haas, F.; Hoeppner, C.; Ketzer, B.; Konopka, R.; Kraemer, M.; Kuhn, R.; Mann, A.; Nagel, T.; Neubert, S.; Paul, S.; Schmitt, L.; Uhl, S.; Weitzel, Q.; Cicuttin, A.; Crespo, M.L.; Diaz, V.; Das, S.; Dasgupta, S.S.; Dhara, L.; Sarkar, S.; Sinha, L.; Denisov, O.Yu.; Donskov, S.V.; Filin, A.; Khaustov, G.V.; Khokhlov, Yu.A.; Kolosov, V.N.; Konstantinov, V.F.; Lednev, A.A.; Mikhailov, Yu.V.; Nikolaenko, V.I.; Polyakov, V.A.; Ryabchikov, D.I.; Samoylenko, V.D.; Doshita, N.; Kondo, K.; Eyrich, W.; Lehmann, A.; Richter, A.; Schroeder, W.; Teufel, A.; Finger, M.; Fischer, H.; Heinsius, F.H.; Herrmann, F.; Kang, D.; Koenigsmann, K.; Lauser, L.; Nerling, F.; Schill, C.; Schopferer, S.; Vossen, A.; Wollny, H.; Gautheron, F.; Hess, C.; Kisselev, Yu.; Koivuniemi, J.H.; Meyer, W.; Reicherz, G.; Gerassimov, S.; Konorov, I.; Goertz, S.; Hasegawa, T.; Matsuda, T.; Horikawa, N.; Ishimoto, S.; Ilgner, C.; Iwata, T.; Michigami, T.; Kouznetsov, O.; CEA IRFU/SPhN Saclay, Gif-sur-Yvette; Soltan Institute for Nuclear Studies and University of Warsaw, Warsaw; Lichtenstadt, J.; Moinester, M.A.; Mallot, G.K.; Stolarski, M.; Marzec, J.; Padee, A.; Sulej, R.; Zaremba, K.; Ziembicki, M.; Mutter, A.; Panzieri, D.; Polak, J.; Srnka, A.; Sulc, M.; Zhao, J.
2010-01-01
Azimuthal asymmetries in semi-inclusive production of positive (h + ) and negative hadrons (h - ) have been measured by scattering 160 GeV muons off longitudinally polarised deuterons at CERN. The asymmetries were decomposed in several terms according to their expected modulation in the azimuthal angle φ of the outgoing hadron. Each term receives contributions from one or several spin and transverse-momentum-dependent parton distribution and fragmentation functions. The amplitudes of all φ-modulation terms of the hadron asymmetries integrated over the kinematic variables are found to be consistent with zero within statistical errors, while the constant terms are nonzero and equal for h + and h - within the statistical errors. The dependencies of the φ-modulated terms versus the Bjorken momentum fraction x, the hadron fractional momentum z, and the hadron transverse momentum p h T were studied. The x dependence of the constant terms for both positive and negative hadrons is in agreement with the longitudinal double-spin hadron asymmetries, measured in semi-inclusive deep-inelastic scattering. The x dependence of the sin φ-modulation term is less pronounced than that in the corresponding HERMES data. All other dependencies of the φ-modulation amplitudes are consistent with zero within the statistical errors. (orig.)
Virtual hadronic and heavy-fermion O({alpha}{sup 2}) corrections to Bhabha scattering
Energy Technology Data Exchange (ETDEWEB)
Actis, Stefano [Inst. fuer Theoretische Physik E, RWTH Aachen (Germany); Czakon, Michal [Wuerzburg Univ. (Germany). Inst. fuer Theoretische Physik und Astrophysik]|[Uniwersytet Slaski, Katowice (Poland). Inst. of Physics and Chemistry of Metals; Gluza, Janusz [Uniwersytet Slaski, Katowice (Poland). Inst. of Physics and Chemistry of Metals; Riemann, Tord [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)
2008-07-15
Effects of vacuum polarization by hadronic and heavy-fermion insertions were the last unknown two-loop QED corrections to high-energy Bhabha scattering. Here we describe the corrections in detail and explore their numerical influence. The hadronic contributions to the virtual O({alpha}{sup 2}) QED corrections to the Bhabha-scattering cross-section are evaluated using dispersion relations and computing the convolution of hadronic data with perturbatively calculated kernel functions. The technique of dispersion integrals is also employed to derive the virtual O({alpha}{sup 2}) corrections generated by muon-, tau- and top-quark loops in the small electron-mass limit for arbitrary values of the internal-fermion masses. At a meson factory with 1 GeV center-of-mass energy the complete effect of hadronic and heavy-fermion corrections amounts to less than 0.5 per mille and reaches, at 10 GeV, up to about 2 per mille. At the Z resonance it amounts to 2.3 per mille at 3 degrees; overall, hadronic corrections are less than 4 per mille. For ILC energies (500 GeV or above), the combined effect of hadrons and heavy fermions becomes 6 per mille at 3 degrees; hadrons contribute less than 20 per mille in the whole angular region. (orig.)
CNI polarimetry and the hadronic spin dependence of pp scattering
International Nuclear Information System (INIS)
Trueman, T.L.
1996-01-01
Methods for limiting the size of hadronic spin-flip in the Coulomb- Nuclear Interference. region are critically assessed. This work was presented at the High Energy Polarimetry Workshop in Amsterdam, Sept. 9, 1996 and the RHIC Spin Collaboration meeting in Marseille, Sept. 17, 1996
Theory of deep inelastic lepton-hadron scattering
International Nuclear Information System (INIS)
Geyer, B.; Robaschik, D.; Wieczorek, E.
1979-01-01
The description of deep inelastic lepton-nucleon scattering in the lowest order of the electromagnetic and weak coupling constants leads to a study of virtual Compton amplitudes and their absorptive parts. Some aspects of quantum chromodynamics are discussed. Deep inelastic scattering enables a central quantity of quantum field theory, namely the light cone behaviour of the current commutator. The moments of structure functions are used for the description of deep inelastic scattering. (author)
Asymptotic angular dependences of exclusive hadron large-angle scattering
International Nuclear Information System (INIS)
Goloskokov, S.V.; Kudinov, A.V.; Kuleshov, S.P.
1979-01-01
Asymptotic approach to the description of the large-angle scattering amplitudes of the meson-nucleon and nucleon-nucleon scattering is studied. The paper is based on the Mandelstam representation and quark counting rules. The crossing summetry, SU-3 symmetry and spin effects are taken into account. Formulae obtained are used for the description of the differential cross sections of πsup(+-)p, pp and pn scattering. The predictions about ksup(+-)p and p anti p scattering are made. It is shown that formulae provide quantitative description of experimental data for the considered reactions
Hadron-proton elastic scattering at 50, 100, and 200 GeV/c momentum
International Nuclear Information System (INIS)
Akerlof, C.W.; Kotthaus, R.; Loveless, R.L.; Meyer, D.I.; Ambats, I.; Meyer, W.T.; Ward, C.E.W.; Eartly, D.P.; Lundy, R.A.; Pruss, S.M.; Yovanovitch, D.D.; Rust, D.R.
1976-01-01
Elastic scattering of hadrons on protons has been measured at momenta of 50, 100, and 200 GeV/c. The meson-proton scattering is found to be independent of momentum and meson type for -t > 0.8 (GeV/c) 2 . The momentum dependence of the pp dip at -t = 1.4 (GeV/c) 2 was investigated. Slope parameters are given
Medium energy hadron-nucleus scattering in the 1/N expansion formalism
International Nuclear Information System (INIS)
Kuyucak, S.; Morrison, I.
1992-01-01
The algebraic-eikonal approach to the medium energy hadron-nucleus scattering is generalized to arbitrary interactions and boson types using the 1/N expansion technique for the interacting boson model. The results are used in a comparative study of proton scattering from deformed nuclei in the sd and sdg boson models. The two models give almost identical results for a pure quadrupole interaction but widely differ when a hexadecapole interaction is included. 25 refs., 3 tabs., 7 figs
Properties of hadronic final states in diffractive deep inelastic ep scattering at DESY HERA
International Nuclear Information System (INIS)
2002-01-01
Characteristics of the hadronic final state of diffractive deep inelastic scattering events ep→eXp were studied in the kinematic range 4 X 2 2 , 70 P <0.03 with the ZEUS detector at the DESY ep collider HERA using an integrated luminosity of 13.8 pb-1. The events were tagged by identifying the diffractively scattered proton using the leading proton spectrometer. The properties of the hadronic final state X were studied in its center-of-mass frame using thrust, thrust angle, sphericity, energy flow, transverse energy flow, and 'seagull' distributions. As the invariant mass of the system increases, the final state becomes more collimated, more aligned, and more asymmetric in the average transverse momentum with respect to the direction of the virtual photon. Comparisons of the properties of the hadronic final state with predictions from various Monte Carlo model generators suggest that the final state is dominated by qq-barg states at the parton level
A Center for the Analyses of Electromagnetic and Hadronic Scattering
Energy Technology Data Exchange (ETDEWEB)
Briscoe, William [George Washington University, Washington, DC (United States)
2017-05-24
The GWU Institute for Nuclear Studies (GWINS) continued activities, and began new initiatives, within the context of a program of Hadronic Physics. The intense program of meson photoproduction measurements has resulted in an extensive set of observables that includes not only cross sections, but also polarization and double-polarization observables. Analysis of these new data contributes toward a resolution of a long-standing issue in baryon spectroscopy, namely, the “missing resonance" problem. The study of baryons containing two and three strange quarks (the Ξ and Ω states, respectively) has begun in order to solve this problem.
Adolph, C.; Akhunzyanov, R.; Alexeev, M. G.; Alexandrov, Yu; Alexeev, G. D.; Amoroso, A.; Andrieux, V.; Anosov, V.; Austregesilo, A.; Badełek, B.; Balestra, F.; Barth, J.; Baum, G.; Beck, R.; Bedfer, Y.; Berlin, A.; Bernhard, J.; Bertini, R.; Bicker, K.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bodlak, M.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Büchele, M.; Burtin, E.; Capozza, L.; Chiosso, M.; Chung, S. U.; Cicuttin, A.; Crespo, M. L.; Curiel, Q.; Dalla Torre, S.; Dasgupta, S. S.; Dasgupta, S.; Denisov, O. Yu; Donskov, S. V.; Doshita, N.; Duic, V.; Dünnweber, W.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P. D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger, Jr; Fischer, H.; Franco, C.; du Fresne von Hohenesche, N.; Friedrich, J. M.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O. P.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Gorzellik, M.; Grabmüller, S.; Grasso, A.; Grube, B.; Guskov, A.; Guthörl, T.; Haas, F.; von Harrach, D.; Hahne, D.; Hashimoto, R.; Heinsius, F. H.; Herrmann, F.; Hinterberger, F.; Höppner, Ch; Horikawa, N.; d'Hose, N.; Huber, S.; Ishimoto, S.; Ivanov, A.; Ivanshin, Yu; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Joerg, P.; Joosten, R.; Kabuß, E.; Kang, D.; Ketzer, B.; Khaustov, G. V.; Khokhlov, Yu A.; Kisselev, Yu; Klein, F.; Klimaszewski, K.; Koivuniemi, J. H.; Kolosov, V. N.; Kondo, K.; Königsmann, K.; Konorov, I.; Konstantinov, V. F.; Kotzinian, A. M.; Kouznetsov, O.; Kral, Z.; Krämer, M.; Kroumchtein, Z. V.; Kuchinski, N.; Kunne, F.; Kurek, K.; Kurjata, R. P.; Lednev, A. A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G. K.; Marchand, C.; Martin, A.; Marzec, J.; Matousek, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Yu V.; Miyachi, Y.; Nagaytsev, A.; Nagel, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V. I.; Novy, J.; Nowak, W. D.; Nunes, A. S.; Orlov, I.; Olshevsky, A. G.; Ostrick, M.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pesek, M.; Peshekhonov, D.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V. A.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Reicherz, G.; Rocco, E.; Rodionov, V.; Rondio, E.; Rychter, A.; Rossiyskaya, N. S.; Ryabchikov, D. I.; Samoylenko, V. D.; Sandacz, A.; Sarkar, S.; Savin, I. A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schlüter, T.; Schmidt, A.; Schmidt, K.; Schmieden, H.; Schönning, K.; Schopferer, S.; Schott, M.; Shevchenko, O. Yu; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Sosio, S.; Sozzi, F.; Srnka, A.; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Szableski, A.; Szameitat, T.; Sznajder, P.; Takekawa, S.; ter Wolbeek, J.; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Vondra, J.; Wang, L.; Weisrock, T.; Wilfert, M.; Windmolders, R.; Wiślicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.
2014-01-01
Spin-averaged asymmetries in the azimuthal distributions of positive and negative hadrons produced in deep inelastic scattering were measured using the CERN SPS longitudinally polarised muon beam at 160GeV/c and a 6LiD target. The amplitudes of the three azimuthal modulations cos φh, cos 2φh and sin
Proceedings of Summer Institute on particle physics: Lepton-Hadron scattering
International Nuclear Information System (INIS)
Hawthorne, J.
1992-09-01
The nineteenth annual SLAC Summer Institute on Particle Physics took place from August 5 to 16, 1991, attracting 236 participants from 10 different countries. The theme was lepton-hadron scattering, the subjects ranging from the pioneering SLAC-MIT experiments, through the new era of e-p collisions to be ushered in by HERA. Richard Taylor led off the Institute with a historical review of lepton-proton scattering experiments, from Rutherford to the 1960s, while Sid Drell laid out the theoretical framework, in terms of parton distributions and sum rules. Frank Sciulli picked up where Richard Taylor left off, at the discovery of scaling violation, and brought us up to the present. Joel Feltesse and Roberto Peccei described the physics opportunities at HERA, most notably the investigation of the low x behavior of structure functions. Traudl Hansl-Kozanecka reviewed the current experimental status of QCD, at e + e - and hadron colliders as well as in deep-inelastic lepton-hadron scattering. Bob Hollebeek lectured on techniques for electromagnetic and hadronic calorimetry. Finally, Bob Siemann gave a series of lectures on the many uses of superconductivity in particle accelerators, from bending magnets at FNAL HERA and the SSC to RF cavities at CEBAF and LEP. Following the school, the topical conference provided us with a spectrum of current experimental and theoretical developments. Lepton-hadron scattering experiments at CERN and Fermilab were well represented. The existence of the 17 0 , keV neutrino was debated in two separate talks. We heard the latest results from the CDF and UA2 hadron collider experiments; from the four LEP experiments; and from ARGUS and CLEO. Also presented were overviews of the rare K decay program at BNL, the CP violation experiments at CERN and Fermilab, B physics, neutrino masses and mixings, and precision electroweak theory
Lepton-hadron scattering from scaling violation to HERA
International Nuclear Information System (INIS)
Sciulli, F.
1992-01-01
The author starts his lecture with a personal remembrance of the appearance of scaling, and its experimental verification with data from Gargamelle and SLAC. Feynmann's parton model was developing, and the discovery and acceptance of quarks fit into this model. He covers areas of the parton model related to u, d, and strange quark densities, and effects of nuclear environment on the parton densities. Deep inelastic scattering results provided significant data and many results for theoretical interpretation. The development and application of quantum chromodynamics (QCD) is reviewed and applied to deep inelastic scattering results. He reviews major sum rules, and takes a phenomenological perspective to describe how the sum rules follow simply from the quark model, and how experiments compare to the predictions. Finally he touches on the many new processes found and sought through the use of the deep inelastic process. The 'new' field of deep inelastic scattering is still going strong
Adolph, C; Akhunzyanov, R; Alexeev, M G; Alexeev, G D; Amoroso, A; Andrieux, V; Anfimov, N V; Anosov, V; Augsten, K; Augustyniak, W; Austregesilo, A; Azevedo, C D R; Badełek, B; Balestra, F; Ball, M; Barth, J; Beck, R; Bedfer, Y; Bernhard, J; Bicker, K; Bielert, E R; Birsa, R; Bodlak, M; Bordalo, P; Bradamante, F; Braun, C; Bressan, A; Buchele, M; Chang, W-C; Chatterjee, C; Chiosso, M; Choi, I; Chung, S-U; Cicuttin, A; Crespo, M L; Curiel, Q; Dalla Torre, S; Dasgupta, S S; Dasgupta, S; Denisov, O Yu; Dhara, L; Donskov, S V; Doshita, N; Dreisbach, Ch; Duic, V; Dunnweber, W; Dziewiecki, M; Efremov, A; Eversheim, P D; Eyrich, W; Faessler, M; Ferrero, A; Finger, M; Finger jr, M; Fischer, H; Franco, C; du Fresne von Hohenesche, N; Friedrich, J M; Frolov, V; Fuchey, E; Gautheron, F; Gavrichtchouk, O P; Gerassimov, S; Giarra, J; Giordano, F; Gnesi, I; Gorzellik, M; Grabmuller, S; Grasso, A; Grosse Perdekamp, M; Grube, B; Grussenmeyer, T; Guskov, A; Haas, F; Hahne, D; Hamar, G; von Harrach, D; Heinsius, F H; Heitz, R; Herrmann, F; Horikawa, N; d’Hose, N; Hsieh, C-Y; Huber, S; Ishimoto, S; Ivanov, A; Ivanshin, Yu; Iwata, T; Jary, V; Joosten, R; Jorg, P; Kabuß, E; Ketzer, B; Khaustov, G V; Khokhlov, Yu A; Kisselev, Yu; Klein, F; Klimaszewski, K; Koivuniemi, J H; Kolosov, V N; Kondo, K; Konigsmann, K; Konorov, I; Konstantinov, V F; Kotzinian, A M; Kouznetsov, O M; Kramer, M; Kremser, P; Krinner, F; Kroumchtein, Z V; Kulinich, Y; Kunne, F; Kurek, K; Kurjata, R P; Lednev, A A; Lehmann, A; Levillain, M; Levorato, S; Lian, Y-S; Lichtenstadt, J; Longo, R; Maggiora, A; Magnon, A; Makins, N; Makke, N; Mallot, G K; Marianski, B; Martin, A; Marzec, J; Matousek, J; Matsuda, H; Matsuda, T; Meshcheryakov, G V; Meyer, M; Meyer, W; Mikhailov, Yu V; Mikhasenko, M; Mitrofanov, E; Mitrofanov, N; Miyachi, Y; Nagaytsev, A; Nerling, F; Neyret, D; Novy, J; Nowak, W-D; Nukazuka, G; Nunes, A S; Olshevsky, A G; Orlov, I; Ostrick, M; Panzieri, D; Parsamyan, B; Paul, S; Peng, J-C; Pereira, F; Pesek, M; Peshekhonov, D V; Pierre, N; Platchkov, S; Pochodzalla, J; Polyakov, V A; Pretz, J; Quaresma, M; Quintans, C; Ramos, S; Regali, C; Reicherz, G; Riedl, C; Roskot, M; Rossiyskaya, N S; Ryabchikov, D I; Rybnikov, A; Rychter, A; Salac, R; Samoylenko, V D; Sandacz, A; Santos, C; Sarkar, S; Savin, I A; Sawada, T; Sbrizzai, G; Schiavon, P; Schmidt, K; Schmieden, H; Schonning, K; Seder, E; Selyunin, A; Silva, L; Sinha, L; Sirtl, S; Slunecka, M; Smolik, J; Srnka, A; Steffen, D; Stolarski, M; Subrt, O; Sulc, M; Suzuki, H; Szabelski, A; Szameitat, T; Sznajder, P; Takekawa, S; Tasevsky, M; Tessaro, S; Tessarotto, F; Thibaud, F; Thiel, A; Tosello, F; Tskhay, V; Uhl, S; Veloso, J; Virius, M; Vondra, J; Wallner, S; Weisrock, T; Wilfert, M; ter Wolbeek, J; Zaremba, K; Zavada, P; Zavertyaev, M; Zemlyanichkina, E; Zhuravlev, N; Ziembicki, M; Zink, A
2016-01-01
Single hadron azimuthal asymmetries in the cross sections of positive and negative hadron production in muon semi-inclusive deep inelastic scattering off longitudinally polarised deuterons are determined using the 2006 COMPASS data and also all deuteron COMPASS data. For each hadron charge, the dependence of the azimuthal asymmetry on the hadron azimuthal angle $\\phi$ is obtained by means of a five-parameter fitting function that besides a $\\phi$-independent term includes four modulations predicted by theory: $\\sin\\phi$, $\\sin 2 \\phi$, $\\sin 3\\phi$ and $\\cos\\phi$. The amplitudes of the five terms have been first extracted for the data integrated over all kinematic variables. In further fits, the $\\phi$-dependence is determined as a function of one of three kinematic variables (Bjorken-$x$, fractional energy of virtual photon taken by the outgoing hadron and hadron transverse momentum), while disregarding the other two. Except the $\\phi$-independent term, all the modulation amplitudes are very small, and no cl...
Large-angle hadron scattering at high energies
International Nuclear Information System (INIS)
Goloskokov, S.V.; Kudinov, A.V.; Kuleshov, S.P.
1981-01-01
Basing on the quasipotential Logunov-Tavkhelidze approach, corrections to the amplitude of high-energy large-angle meson-nucleon scattering are estimated. The estimates are compared with the available experimental data on pp- and π +- p-scattering, so as to check the adequacy of the suggested scheme to account for the preasymptotic deffects. The compared results are presented in the form of tables and graphs. The following conclusions are drawn: 1. the account for corrections, due to the long-range interaction, to the amplituda gives a good aghreee main asymptotic termment between the theoretical and experimental data. 2. in the case of π +- p- scattering the corrections prove to be comparable with the main asymptotic term up to the values of transferred pulses psub(lambdac)=50 GeV/c, which results in a noticeable deviation form the quark counting rules at such energies. Nevertheless, the preasymptotic formulae do well, beginning with psub(lambdac) approximately 6 GeV/c. In case of pp-scattering the corrections are mutually compensated to a considerable degree, and the deviation from the quark counting rules is negligible
Hadron--deuteron scattering at 50 GeV
International Nuclear Information System (INIS)
Levinson, L.J.
1978-06-01
The forward scattering of π + , π - , and protons on deuterons and protons was measured with a single arm spectrometer at the Fermi National Accelerator Laboratory. The energy was 50 GeV and the invariant 4-momentum transfer range was .06 2 for π + and p, and .06 - . The missing mass, determined by the spectrometer, selected proton elastic and deuteron elastic-plus-breakup scattering, rejecting particle and resonance production events. The measured proton and deuteron differential cross sections were analyzed in the context of the Glauber Theory of deuteron elastic-plus-breakup scattering and a neutron elastic differential cross section was extracted. The theory and analysis were tested by comparing the π + n cross section extracted from the π + d and n + p data with the π - p data; by I-spin symmetry the π + n cross section must equal the π - p. The same test was done for π - n. The proton--neutron elastic differential cross section was then extracted from the pd and pp data. The theory and the data were not found to be consistent within the random errors. Systematic errors are probably the cause; several possible systematic errors are discussed. Also an attempt to use recoil particle detectors to extract the deuteron elastic and the neutron cross sections is reported
Transverse spin effects in hadron-pair production from semi-inclusive deep inelastic scattering
Adolph, C.; Alexakhin, V.Yu.; Alexeev, G.D.; Amoroso, A.; Antonov, A.A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Bedfer, Y.; Bernhard, J.; Bertini, R.; Bettinelli, M.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Burtin, E.; Chaberny, D.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Crespo, M.L.; Dalla Torre, S.; Das, S.; Dasgupta, S.S.; Dhara, L.; Donskov, S.V.; Duic, V.; Dunnweber, W.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; jr., M.Finger; Fischer, H.; Franco, C.; Friedrich, J.M.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.P.; Gazda, R.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Grabmuller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Guthorl, T.; Haas, F.; von Harrach, D.; Heinsius, F.H.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Hoppner, Ch.; d'Hose, N.; Huber, S.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jasinski, P.; Joosten, R.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu.A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.H.; Kolosov, V.N.; Konigsmann, K.; Konstantinov, V.F.; Korzenev, A.; Kotzinian, A.M.; Kramer, M.; Kroumchtein, Z.V.; Kunne, F.; Kurek, K.; Lauser, L.; Lednev, A.A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G.K.; Mann, A.; Marchand, C.; Martin, A.; Marzec, J.; Massmann, F.; Matsuda, T.; Meyer, W.; Michigami, T.; Mikhailov, Yu.V.; Moinester, M.A.; Morreale, A.; Nagaytsev, A.; Nagel, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.I.; Nowak, W.D.; Nunes, A.S.; Olshevsky, A.G.; Ostrick, M.; Padee, A.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Perevalova, E.; Pesaro, G.; Peshekhonov, D.V.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polyakov, V.A.; Pontecorvo, G.; Pretz, J.; Quaresma, M.; Quintans, C.; Rajotte, J.F.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Richter, A.; Rondio, E.; Rossiyskaya, N.S.; Ryabchikov, D.I.; Samoylenko, V.D.; Sandacz, A.; Sapozhnikov, M.G.; Sarkar, S.; Savin, I.A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schluter, T.; Schmidt, K.; Schmitt, L.; Schonning, K.; Schopferer, S.; Schott, M.; Shevchenko, O.Yu.; Silva, L.; Sinha, L.; Slunecka, M.; Smirnov, G.I.; Sosio, S.; Sozzi, F.; Srnka, A.; Stolarski, M.; Sulc, M.; Sulej, R.; Sznajder, P.; Takekawa, S.; Wolbeek, J.Ter; Tessaro, S.; Tessarotto, F.; Teufel, A.; Tkatchev, L.G.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Vlassov, N.V.; Vossen, A.; Wang, L.; Windmolders, R.; Wislicki, W.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zhuravlev, N.; Zvyagin, A.
2012-06-18
First measurements of azimuthal asymmetries in hadron-pair production in deep-inelastic scattering of muons on transversely polarised ^6LiD (deuteron) and NH_3 (proton) targets are presented. The data were taken in the years 2002-2004 and 2007 with the COMPASS spectrometer using a muon beam of 160 GeV/c at the CERN SPS. The asymmetries provide access to the transversity distribution functions, without involving the Collins effect as in single hadron production. The sizeable asymmetries measured on the NH_ target indicate non-vanishing u-quark transversity and two-hadron interference fragmentation functions. The small asymmetries measured on the ^6LiD target can be interpreted as indication for a cancellation of u- and d-quark transversities.
International Nuclear Information System (INIS)
Curiel-Garcia, Quiela-Marina
2014-01-01
One of the goals of the COMPASS experience is the study of the nucleon spin structure. Data were taken from a polarized muon beam (160 GeV/c) scattering off a polarized target ( 6 LiD or NH 3 ). In this context, the need of a precise knowledge of quark Fragmentation Functions (final-state hadronization of quarks q into hadrons h, FFs) was raised. The FFs can be extracted from hadron multiplicities produced in Semi-Inclusive Deep Inelastic Scattering (SIDIS). This thesis presents the measurement of charged hadrons (pions and kaons) multiplicities from SIDIS data collected in 2006. The data cover a large kinematical range: Q 2 ≥1 (GeV/c)2, y belongs to [0.1,0.9], x belongs to [0.004,0.7] and W belongs to [5,17] GeV. These multiplicities provide an important input for global QCD analyses of world data at NLO, aiming at the FFs determination. (author) [fr
Electron-deuteron scattering in a relativistic theory of hadrons
International Nuclear Information System (INIS)
Phillips, D.
1998-11-01
The author reviews a three-dimensional formalism that provides a systematic way to include relativistic effects including relativistic kinematics, the effects of negative-energy states, and the boosts of the two-body system in calculations of two-body bound-states. He then explains how to construct a conserved current within this relativistic three-dimensional approach. This general theoretical framework is specifically applied to electron-deuteron scattering both in impulse approximation and when the ρπγ meson-exchange current is included. The experimentally-measured quantities A, B, and T 20 are calculated over the kinematic range that is probed in Jefferson Lab experiments. The role of both negative-energy states and meson retardation appears to be small in the region of interest
Partial-wave analyses of hadron scattering below 2 GeV
International Nuclear Information System (INIS)
Arndt, R.A.; Roper, L.D.
1990-01-01
The Center for Analysis of Particle Scattering (CAPS) in the Department of Physics at Virginia Polytechnic Institute and State University has analyzed basic two-body hadron reactions below 2 GeV for the last two decades. Reactions studied were nucleon-nucleon, pion-nucleon, K + -nucleon and pion photoproduction systems. In addition to analyses of these systems, a computer graphics system (SAID) has been developed and disseminated to over 200 research institutions using VAX computers. 8 refs
Partial-wave analyses of hadron scattering below 2 GeV
International Nuclear Information System (INIS)
Arndt, R.A.; Roper, L.D.
1991-01-01
The Center for Analysis of Particle Scattering (CAPS) in the Department of Physics at Virginia Polytechnic Institute and State University has analyzed basic two-body hadron reactions below 2 GeV for the last two decades. Reactions studied were nucleon-nucleon, pion-nucleon, K + -nucleon and pion photoproduction systems. In addition to analyses of these systems, a computer graphics system (SAID) has been developed and disseminated to over 250 research institutions using VAX computers. The computer-interactive system for disseminating information on basic scattering reactions is also accessible to the physics community through TELNET on the VPI ampersand SU physics department VAX. 6 refs
Measurement of Hadron Multiplicities in Deep Inelastic Muon-Nucleon Scattering
du Fresne von Hohenesche, Nicolas
2016-06-02
In deep-inelastic muon-nucleon scattering, a single quark can be ejected out of the nucleon by the absorption of a high-energy photon. Such a free isolated quark has never been observed in nature. In quantum chromodynamics (QCD), coloured objects, such as a single quark, create additional quark anti-quark pairs out of the colour field and the final state comprises a jet of hadrons. The hadronisation process can be described by fragmentation functions D_q^h, the probability that a quark with the flavour q turns into a hadron of the type h. Similar to the parton distribution function, the fragmentation functions are fundamental, universal and process-independent quantities. The fragmentation functions are measured with the COM- PASS spectrometer in muon-nucleon scattering. The observables are the hadron multiplicities M_h. The COMPASS experiment consists of a two-stage magnetic spectrometer located at the M2 beam line of the Super Proton Synchrotron at CERN and uses a polarised muon beam on a nuclear fixed targ...
Quark charge retention in final state hadrons form deep inelastic muon scattering
International Nuclear Information System (INIS)
Albanese, J.P.; Blum, D.; Heusse, P.; Jaffre, M.; Jacholkowska, A.; Pascaud, C.; Carr, J.; Chima, J.S.; Clifft, R.; Edwards, M.; Norton, P.R.; Oakham, F.G.; Thompson, J.C.; Figiel, J.; Hoppe, C.; Janata, F.; Preissner, H.; Rondio, E.; Studt, M.; La Torre, A. de; Dengler, F.; Derado, I.; Eckardt, V.; Manz, A.; Schmitz, N.; Shiers, J.; Wolf, G.; Arneodo, M.; Arvidson, A.; Aubert, J.J.; Becks, K.H.; Bee, C.; Benchouk, C.; Bird, I.; Boehm, E.; Braun, H.; Brown, S.; Brueck, H.; Calen, H.; Callebaut, D.; Cobb, J.H.; Combley, F.; Coughlan, J.; Court, G.R.; D'Agostini, G.; Dahlgren, S.; Davies, J.K.; Dau, W.D.; Dreyer, T.; Drees, J.; Dumont, J.J.; Dueren, M.; Edwards, A.; Ernst, T.; Ferrero, M.I.; Foster, J.; Gamet, R.; Geddes, N.; Giubellino, P.; Grafstroem, P.; Grard, F.; Gustafsson, L.; Haas, J.; Hagberg, E.; Hasert, F.J.; Hayman, P.; Johnson, A.S.; Kabuss, E.M.; Krueger, J.; Kullander, S.; Landgraf, U.; Lanske, D.; Loken, J.; Long, K.; Mohr, W.; Montanet, F.; Mount, R.P.; Paul, L.; Payre, P.; Peroni, C.; Pettingale, J.; Poetsch, M.; Renton, P.; Rith, K.; Schlagboehmer, A.; Schroeder, T.; Schultze, K.; Sloan, T.; Stier, H.E.; Stockhausen, W.; Taylor, G.; Wahlen, H.; Wallucks, W.; Whalley, M.; Williams, W.S.C.; Wheeler, S.; Wimpenny, S.; Windmolders, R.
1984-01-01
The net charge of final state hadrons in both the current and target fragmentation regions has been measured in a 280 GeV/c muon-proton scattering experiment. A clean kinematic separation of the two regions in the centre-of-mass rapidity is demonstrated. The dependence on chisub(Bj) of the mean net charges is found to be consistent with a large contribution of sea quarks at small chisub(Bj) and with the dominance of valence quarks at large chisub(Bj) thus giving clear confirmation of the quark-parton model. It is also shown that the leading forward hadron has a high probability of containing the struck quark. (orig.)
Hadron Transverse Momentum Distributions in Muon Deep Inelastic Scattering at 160 GeV/$c$
Adolph, C; Alexakhin, V Yu; Alexandrov, Yu; Alexeev, G D; Amoroso, A; Andrieux, V; Austregesilo, A; Badelek, B; Balestra, F; Barth, J; Baum, G; Bedfer, Y; Berlin, A; Bernhard, J; Bertini, R; Bicker, K; Bieling, J; Birsa, R; Bisplinghoff, J; Boer, M; Bordalo, P; Bradamante, F; Braun, C; Bravar, A; Bressan, A; Buchele, M; Burtin, E; Capozza, L; Chiosso, M; Chung, S U; Cicuttin, A; Crespo, M L; Dalla Torre, S; Dasgupta, S S; Dasgupta, S; Denisov, O Yu; Donskov, S V; Doshita, N; Duic, V; Dunnweber, W; Dziewiecki, M; Efremov, A; Elia, C; Eversheim, P D; Eyrich, W; Faessler, M; Ferrero, A; Filin, A; Finger, M; Finger, M jr; Fischer, H; Franco, C; du Fresne von Hohenesche, N; Friedrich, J M; Frolov, V; Garfagnini, R; Gautheron, F; Gavrichtchouk, O P; Gerassimov, S; Geyer, R; Giorgi, M; Gnesi, I; Gobbo, B; Goertz, S; Grabmuller, S; Grasso, A; Grube, B; Gushterski, R; Guskov, A; Guthorl, T; Haas, F; von Harrach, D; Heinsius, F H; Herrmann, F; Hess, C; Hinterberger, F; Hoppner, Ch; Horikawa, N; d'Hose, N; Huber, S; Ishimoto, S; Ivanshin, Yu; Iwata, T; Jahn, R; Jary, V; Jasinski, P; Joosten, R; Kabuss, E; Kang, D; Ketzer, B; Khaustov, G V; Khokhlov, Yu A; Kisselev, Yu; Klein, F; Klimaszewski, K; Koivuniemi, J H; Kolosov, V N; Kondo, K; Konigsmann, K; Konorov, I; Konstantinov, V F; Kotzinian, A M; Kouznetsov, O; Kramer, M; Kroumchtein, Z V; Kuchinski, N; Kunne, F; Kurek, K; Kurjata, R P; Lednev, A A; Lehmann, A; Levorato, S; Lichtenstadt, J; Maggiora, A; Magnon, A; Makke, N; Mallot, G K; Mann, A; Marchand, C; Martin, A; Marzec, J; Matsuda, H; Matsuda, T; Meshcheryakov, G; Meyer, W; Michigami, T; Mikhailov, Yu V; Morreale, A; Nagaytsev, A; Nagel, T; Nerling, F; Neubert, S; Neyret, D; Nikolaenko, V I; Novy, J; Nowak, W D; Nunes, A.S; Olshevsky, A G; Ostrick, M; Panknin, R; Panzieri, D; Parsamyan, B; Paul, S; Piragino, G; Platchkov, S; Pochodzalla, J; Polak, J; Polyakov, V A; Pretz, J; Quaresma, M; Quintans, C; Rajotte, J F; Ramos, S; Reicherz, G; Rocco, E; Rodionov, V; Rondio, E; Rossiyskaya, N S; Ryabchikov, D I; Samoylenko, V D; Sandacz, A; Sapozhnikov, M G; Sarkar, S; Savin, I A; Sbrizzai, G; Schiavon, P; Schill, C; Schluter, T; Schmidt, A; Schmidt, K; Schmitt, L; Schmiden, H; Schonning, K; Schopferer, S; Schott, M; Shevchenko, O Yu; Silva, L; Sinha, L; Sirtl, S; Slunecka, M; Sosio, S; Sozzi, F; Srnka, A; Steiger, L; Stolarski, M; Sulc, M; Sulej, R; Suzuki, H; Sznajder, P; Takekawa, S; Ter Wolbeek, J; Tessaro, S; Tessarotto, F; Thibaud, F; Uhl, S; Uman, I; Vandenbroucke, M; Virius, M; Wang, L; Weisrock, T; Wilfert, M; Windmolders, R; Wislicki, W; Wollny, H; Zaremba, K; Zavertyaev, M; Zemlyanichkina, E; Zhuravlev, N; Ziembicki, M
2013-01-01
Multiplicities of charged hadrons produced in deep inelastic muon scattering off a $^6$LiD target have been measured as a function of the DIS variables $x_{Bj}$, $Q^2$, $W^2$ and the final state hadron variables $p_T$ and $z$. The $p_T^2$ distributions are fitted with a single exponential function at low values of $p_T^2$ to determine the dependence of $\\langle p_T^2 \\rangle$ on $x_{Bj}$, $Q^2$, $W^2$ and $z$. The $z$-dependence of $\\langle p_T^2 \\rangle$ is shown to be a potential tool to extract the average intrinsic transverse momentum squared of partons, $\\langle k_{\\perp}^2 \\rangle$, as a function of $x_{Bj}$ and $Q^2$ in a leading order QCD parton model.
Adolph, C.; Alekseev, M.G.; Alexandrov, Yu.; Alexeev, G.D.; Amoroso, A.; Andrieux, V.; Anosov, V.; Austregesilo, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Beck, R.; Bedfer, Y.; Berlin, A.; Bernhard, J.; Bertini, R.; Bicker, K.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bodlak, M.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Buchele, M.; Burtin, E.; Capozza, L.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Crespo, M.L.; Curiel, Q.; Dalla Torre, S.; Dasgupta, S.S.; Dasgupta, S.; Denisov, O.Yu.; Donskov, S.V.; Doshita, N.; Duic, V.; Dunnweber, W.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger jr, M.; Fischer, H.; Franco, C.; du Fresne von Hohenesche, N.; Friedrich, J.M.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.P.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Gorzellik, M.; Grabmuller, S.; Grasso, A.; Grube, B.; Guskov, A.; Guthorl, T.; Haas, F.; von Harrach, D.; Hahne, D.; Hashimoto, R.; Heinsius, F.H.; Herrmann, F.; Hinterberger, F.; Hoppner, Ch.; Horikawa, N.; d'Hose, N.; Huber, S.; Ishimoto, S.; Ivanov, A.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Joerg, P.; Joosten, R.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu. A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koivuniemi, J.H.; Kolosov, V.N.; Kondo, K.; Konigsmann, K.; Konorov, I.; Konstantinov, V.F.; Kotzinian, A.M.; Kouznetsov, O.; Kral, Z.; Kramer, M.; Kroumchtein, Z.V.; Kuchinski, N.; Kunne, F.; Kurek, K.; Kurjata, R.P.; Lednev, A.A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G.K.; Marchand, C.; Martin, A.; Marzec, J.; Matousek, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Yu. V.; Miyachi, Y.; Nagaytsev, A.; Nagel, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.I.; Novy, J.; Nowak, W.D.; Nunes, A.S.; Orlov, I.; Olshevsky, A.G.; Ostrick, M.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pesek, M.; Peshekhonov, D.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.A.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Reicherz, G.; Rocco, E.; Rodionov, V.; Rondio, E.; Rychter, A.; Rossiyskaya, N.S.; Ryabchikov, D.I.; Samoylenko, V.D.; Sandacz, A.; Sarkar, S.; Savin, I.A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schluter, T.; Schmidt, A.; Schmidt, K.; Schmieden, H.; Schonning, K.; Schopferer, S.; Schott, M.; Shevchenko, O.Yu.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Sosio, S.; Sozzi, F.; Srnka, A.; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Szabeleski, A.; Szameitat, T.; Sznajder, P.; Takekawa, S.; ter Wolbeek, J.; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Vondra, J.; Wang, L.; Weisrock, T.; Wilfert, M.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.
2014-01-01
Spin-averaged asymmetries in the azimuthal distributions of positive and negative hadrons produced in deep inelastic scattering were measured using the CERN SPS muon beam at $160$ GeV/c and a $^6$LiD target. The amplitudes of the three azimuthal modulations $\\cos\\phi_h$, $\\cos2\\phi_h$ and $\\sin\\phi_h$ were obtained binning the data separately in each of the relevant kinematic variables $x$, $z$ or $p_T^{\\,h}$ and binning in a three-dimensional grid of these three variables. The amplitudes of the $\\cos \\phi_h$ and $\\cos 2\\phi_h$ modulations show strong kinematic dependencies both for positive and negative hadrons.
Directory of Open Access Journals (Sweden)
C. Adolph
2014-09-01
Full Text Available Spin-averaged asymmetries in the azimuthal distributions of positive and negative hadrons produced in deep inelastic scattering were measured using the CERN SPS longitudinally polarised muon beam at 160 GeV/c and a 6LiD target. The amplitudes of the three azimuthal modulations cosϕh, cos2ϕh and sinϕh were obtained binning the data separately in each of the relevant kinematic variables x, z or pTh and binning in a three-dimensional grid of these three variables. The amplitudes of the cosϕh and cos2ϕh modulations show strong kinematic dependencies both for positive and negative hadrons.
Hadron transverse momentum distributions in muon deep inelastic scattering at 160 GeV/c
International Nuclear Information System (INIS)
Adolph, C.; Braun, C.; Eyrich, W.; Lehmann, A.; Schmidt, A.; Alekseev, M.G.; Birsa, R.; Bravar, A.; Dalla Torre, S.; Dasgupta, S.S.; Gobbo, B.; Sozzi, F.; Steiger, L.; Tessaro, S.; Tessarotto, F.; Alexakhin, V.Yu.; Alexeev, G.D.; Efremov, A.; Gavrichtchouk, O.P.; Gushterski, R.; Guskov, A.; Ivanshin, Yu.; Kroumchtein, Z.V.; Kuchinski, N.; Meshcheryakov, G.; Nagaytsev, A.; Olshevsky, A.G.; Rodionov, V.; Rossiyskaya, N.S.; Sapozhnikov, M.G.; Savin, I.A.; Shevchenko, O.Yu.; Zemlyanichkina, E.; Zhuravlev, N.; Alexandrov, Yu.; Zavertyaev, M.; Amoroso, A.; Balestra, F.; Bertini, R.; Chiosso, M.; Garfagnini, R.; Gnesi, I.; Grasso, A.; Kotzinian, A.M.; Parsamyan, B.; Piragino, G.; Sosio, S.; Andrieux, V.; Bedfer, Y.; Boer, M.; Burtin, E.; Capozza, L.; Ferrero, A.; Hose, N. d'; Kunne, F.; Magnon, A.; Marchand, C.; Morreale, A.; Neyret, D.; Platchkov, S.; Thibaud, F.; Vandenbroucke, M.; Wollny, H.; Austregesilo, A.; Bicker, K.; Badelek, B.; Barth, J.; Bieling, J.; Goertz, S.; Klein, F.; Panknin, R.; Pretz, J.; Windmolders, R.; Baum, G.; Berlin, A.; Gautheron, F.; Hess, C.; Kisselev, Yu.; Koivuniemi, J.H.; Meyer, W.; Reicherz, G.; Wang, L.; Bernhard, J.; Harrach, D. von; Jasinski, P.; Kabuss, E.; Kang, D.; Ostrick, M.; Pochodzalla, J.; Weisrock, T.; Wilfert, M.; Bisplinghoff, J.; Eversheim, P.D.; Hinterberger, F.; Jahn, R.; Joosten, R.; Schmiden, H.; Bordalo, P.; Franco, C.; Nunes, A.S.; Quaresma, M.; Quintans, C.; Ramos, S.; Silva, L.; Stolarski, M.; Bradamante, F.; Bressan, A.; Duic, V.; Elia, C.; Giorgi, M.; Levorato, S.; Martin, A.; Sbrizzai, G.; Schiavon, P.; Buechele, M.; Fischer, H.; Guthoerl, T.; Heinsius, F.H.; Herrmann, F.; Koenigsmann, K.; Nerling, F.; Nowak, W.D.; Schill, C.; Schmidt, K.; Schopferer, S.; Sirtl, S.; Ter Wolbeek, J.; Chung, S.U.; Friedrich, J.M.; Grabmueller, S.; Grube, B.; Haas, F.; Hoeppner, C.; Huber, S.; Ketzer, B.; Kraemer, M.; Mann, A.; Nagel, T.; Neubert, S.; Paul, S.; Schmitt, L.; Uhl, S.; Cicuttin, A.; Crespo, M.L.; Dasgupta, S.; Sarkar, S.; Sinha, L.; Denisov, O.Yu.; Maggiora, A.; Takekawa, S.; Donskov, S.V.; Filin, A.; Khaustov, G.V.; Khokhlov, Yu.A.; Kolosov, V.N.; Konstantinov, V.F.; Lednev, A.A.; Mikhailov, Yu.V.; Nikolaenko, V.I.; Polyakov, V.A.; Ryabchikov, D.I.; Samoylenko, V.D.; Doshita, N.; Ishimoto, S.; Iwata, T.; Kondo, K.; Matsuda, H.; Michigami, T.; Suzuki, H.; Duennweber, W.; Faessler, M.; Geyer, R.; Rajotte, J.F.; Schlueter, T.; Uman, I.; Dziewiecki, M.; Kurjata, R.P.; Marzec, J.; Zaremba, K.; Ziembicki, M.; Finger, M.; Finger, M.; Slunecka, M.; Du Fresne von Hohenesche, N.; Frolov, V.; Mallot, G.K.; Rocco, E.; Schoenning, K.; Schott, M.; Gerassimov, S.; Konorov, I.; Horikawa, N.; Jary, V.; Novy, J.; Virius, M.; Klimaszewski, K.; Kurek, K.; Rondio, E.; Sandacz, A.; Sulej, R.; Sznajder, P.; Wislicki, W.; Kouznetsov, O.; Lichtenstadt, J.; Makke, N.; Matsuda, T.; Panzieri, D.; Polak, J.; Srnka, A.; Sulc, M.
2013-01-01
Multiplicities of charged hadrons produced in deep inelastic muon scattering off a 6 LiD target have been measured as a function of the DIS variables x Bj , Q 2 , W 2 and the final state hadron variables p T and z. The p T 2 distributions are fitted with a single exponential function at low values of p T 2 to determine the dependence of left angle p T 2 right angle on x Bj , Q 2 , W 2 and z. The z-dependence of left angle p T 2 right angle is shown to be a potential tool to extract the average intrinsic transverse momentum squared of partons, left angle k perpendicular to 2 right angle, as a function of x Bj and Q 2 in a leading order QCD parton model. (orig.)
Ikeda, Yoichi
2018-03-01
We present recent progress of lattice QCD studies on hadronic interactions which play a crucial role to understand the properties of atomic nuclei and hadron resonances. There are two methods, the plateau method (or the direct method) and the HAL QCD method, to study the hadronic interactions. In the plateau method, the determination of a ground state energy from the temporal correlation functions of multi-hadron systems is a key to reliably extract the physical observables. It turns out that, due to the contamination of excited elastic scattering states nearby, one can easily be misled by a fake plateau into extracting the ground state energy. We introduce a consistency check (sanity check) which can rule out obviously false results obtained from a fake plateau, and find that none of the results obtained at the moment for two-baryon systems in the plateau method pass the test. On the other hand, the HAL QCD method is free from the fake-plateau problem. We investigate the systematic uncertainties of the HAL QCD method, which are found to be well controlled. On the basis of the HAL QCD method, the structure of the tetraquark candidate Zc(3900), which was experimentally reported in e+e- collisions, is studied by the s-wave two-meson coupled-channel scattering. The results show that the Zc(3900) is not a conventional resonance but a threshold cusp. A semi-phenomenological analysis with the coupled-channel interaction to the experimentally observed decay mode is also presented to confirm the conclusion.
Hadronization in semi-inclusive deep-inelastic scattering on nuclei
Energy Technology Data Exchange (ETDEWEB)
Airapetian, A [Michigan Univ., Ann Arbor, MI (United States). Randall Lab. of Physics; Akopov, N; Akopov, Z [Yerevan Physics Institute (AR)
2007-04-15
A series of semi-inclusive deep-inelastic scattering measurements on deuterium, helium, neon, krypton, and xenon targets has been performed in order to study hadronization. The data were collected with the HERMES detector at the DESY laboratory using a 27.6 GeV positron or electron beam. Hadron multiplicities on nucleus A relative to those on the deuteron, R{sup h}{sub A}, are presented for various hadrons ({pi}{sup +}, {pi}{sup -}, {pi}{sup 0}, K{sup +}, K{sup -}, p, and anti p) as a function of the virtual-photon energy {nu}, the fraction z of this energy transferred to the hadron, the photon virtuality Q{sup 2}, and the hadron transverse momentum squared p{sup 2}{sub t}. The data reveal a systematic decrease of R{sup h}{sub A} with the mass number A for each hadron type h. Furthermore, R{sup h}{sub A} increases (decreases) with increasing values of {nu}(z), increases slightly with increasing Q{sup 2}, and is almost independent of p{sup 2}{sub t}, except at large values of p{sup 2}{sub t}. For pions two-dimensional distributions also are presented. These indicate that the dependences of R{sup {pi}}{sub A} on {nu} and z can largely be described as a dependence on a single variable L{sub c}, which is a combination of {nu} and z. The dependence on L{sub c} suggests in which kinematic conditions partonic and hadronic mechanisms may be dominant. The behaviour of R{sup {pi}}{sub A} at large p{sup 2}{sub t} constitutes tentative evidence for a partonic energy-loss mechanism. The A-dependence of R{sup h}{sub A} is investigated as a function of {nu}, z, and of L{sub c}. It approximately follows an A{sup {alpha}} form with {alpha}{approx}0.5-0.6. (orig.)
Topological cross sections in hadron-nucleus collisions and multiple scattering theory
International Nuclear Information System (INIS)
Zoller, V.R.
1987-01-01
The multiple scattering theory supplemented with cutting rules of Abramovsky, V.A., Gribov, V.N., Kancheli, O.V. is applied to calculation of the hadron-nucleus interaction cross sections. In contrast to standard Glauber approach neither smalness of the interaction radius compared to the nuclear radii nor Gaussian form of the hN-interaction profile function are assumed. The theory of the supercritical pomeron are used. However all the results are more general and do not depend on the parametrization of the pomeron pole amplitude. The region of validity of the widely used approximate formulae for topological and total hA-interaction cross sections are discussed
International Nuclear Information System (INIS)
Safronov, A.N.
1983-01-01
A system of nonsingular integral equations is formulated for the calculation of hadron-hadron partial amplitudes in the low-and intermediate-energy range taking into account meson and quark-gluon degrees of freedom. The quark-gluon degrees of freedom are included in the framework of the composite-quark-bag model, and the meson degrees of freedom are treated by the methods of the relativistic quantum field theory. It is shown that including the quark-gluon degrees of freedom leads to suppression of meson exchange effects, mostly of heavy meson (rho, ω) exchanges. The method has been applied to the calculation of the 3 S 1 , 1 S 0 , 3 P 0 , 3 P 1 , and 1 P 1 phase shifts for the nucleon-nucleon scattering at the incident nucleon energies T=0-1050 MeV, as well as to the S-wave scattering lengths and effective radii
International Nuclear Information System (INIS)
Babaev, Z.R.; Shchelkachev, A.V.
1991-01-01
Prospects of decribing polarization effects within the framework of quark-parton models (QPM) using a density matrix in order to describe the parton spin states in hadrons are discussed. Such an approach allows one to get rid of contradictions occuring when describing the QPM of reactions of hadrons polarized in perpendicular to the scattering plane in case of applying spin distribution functions. Different model predictions for the observed one- and two-spin correlations in elastic nucleon-nucleon scattering are analyzed. 12 refs., 2 tabs
Hadron transverse momentum distributions in muon deep inelastic scattering at 160 GeV/c
Energy Technology Data Exchange (ETDEWEB)
Adolph, C.; Braun, C.; Eyrich, W.; Lehmann, A.; Schmidt, A. [Universitaet Erlangen-Nuernberg, Physikalisches Institut, Erlangen (Germany); Alekseev, M.G.; Birsa, R.; Bravar, A.; Dalla Torre, S.; Dasgupta, S.S.; Gobbo, B.; Sozzi, F.; Steiger, L.; Tessaro, S.; Tessarotto, F. [Trieste Section of INFN, Trieste (Italy); Alexakhin, V.Yu.; Alexeev, G.D.; Efremov, A.; Gavrichtchouk, O.P.; Gushterski, R.; Guskov, A.; Ivanshin, Yu.; Kroumchtein, Z.V.; Kuchinski, N.; Meshcheryakov, G.; Nagaytsev, A.; Olshevsky, A.G.; Rodionov, V.; Rossiyskaya, N.S.; Sapozhnikov, M.G.; Savin, I.A.; Shevchenko, O.Yu.; Zemlyanichkina, E.; Zhuravlev, N. [Joint Institute for Nuclear Research, Dubna, Moscow region (Russian Federation); Alexandrov, Yu.; Zavertyaev, M. [Lebedev Physical Institute, Moscow (Russian Federation); Amoroso, A.; Balestra, F.; Bertini, R.; Chiosso, M.; Garfagnini, R.; Gnesi, I.; Grasso, A.; Kotzinian, A.M.; Parsamyan, B.; Piragino, G.; Sosio, S. [University of Turin, Department of Physics (Italy); Torino Section of INFN, Turin (Italy); Andrieux, V.; Bedfer, Y.; Boer, M.; Burtin, E.; Capozza, L.; Ferrero, A.; Hose, N. d'
2013-08-15
Multiplicities of charged hadrons produced in deep inelastic muon scattering off a {sup 6}LiD target have been measured as a function of the DIS variables x{sub Bj}, Q{sup 2}, W{sup 2} and the final state hadron variables p{sub T} and z. The p{sub T}{sup 2} distributions are fitted with a single exponential function at low values of p{sub T}{sup 2} to determine the dependence of left angle p{sub T}{sup 2} right angle on x{sub Bj}, Q{sup 2}, W{sup 2} and z. The z-dependence of left angle p{sub T}{sup 2} right angle is shown to be a potential tool to extract the average intrinsic transverse momentum squared of partons, left angle k {sub perpendicular} {sub to} {sup 2} right angle, as a function of x{sub Bj} and Q{sup 2} in a leading order QCD parton model. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Carloni Calame, C. [Southampton Univ. (United Kingdom). School of Physics; Czyz, H.; Gluza, J.; Gunia, M. [Silesia Univ., Katowice (Poland). Dept. of Field Theory and Particle Physics; Montagna, G. [Pavia Univ. (Italy). Dipt. di Fisica Nucleare e Teorica; INFN, Sezione di Pavia (Italy); Nicrosini, O.; Piccinini, F. [INFN, Sezione di Pavia (Italy); Riemann, T. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Worek, M. [Wuppertal Univ. (Germany). Fachbereich C Physik
2011-07-15
Virtual fermionic N{sub f}=1 and N{sub f}=2 contributions to Bhabha scattering are combined with realistic real corrections at next-to-next-to-leading order in QED. The virtual corrections are determined by the package BHANNLOHF, and real corrections with the Monte Carlo generators BHAGEN-1PH, HELAC-PHEGAS and EKHARA. Numerical results are discussed at the energies of and with realistic cuts used at the {phi} factory DA{phi}NE, at the B factories PEP-II and KEK, and at the charm/{tau} factory BEPC II. We compare these complete calculations with the approximate ones realized in the generator BABAYAGA rate at NLO used at meson factories to evaluate their luminosities. For realistic reference event selections we find agreement for the NNLO leptonic and hadronic corrections within 0.07% or better and conclude that they are well accounted for in the generator by comparison with the present experimental accuracy. (orig.)
Hadron production from $\\mu-Deuteron$ scattering at $\\sqrt{s}=17 GeV$ at COMPASS
Morreale, Astrid
2011-01-01
Hadrons proceeding from quasi-real photo-production are one of the many probes accesible at the Common Muon Proton Apparatus for Structure and Spectroscopy (COMPASS) at CERN. These hadrons provide information on the scattering between photon and partons through $\\gamma$-gluon($g$) direct channels as well as $q-g$ resolved processes. Comparisons of unpolarized differential cross section measurements to next-to-leading order (NLO) pQCD calculations are essential to develop our understanding of proton-proton and lepton-nucleon scattering at varying center of mass energies. These measurements are important to asses the applicability of NLO pQCD in interpreting polarized processes. In this talk we will present the unidentified charged separated hadron cross-sections measured by the COMPASS experiment at center of mass energy of $\\sqrt{s}$ = 17 $GeV$, low $Q^{2}$ (Q$^{2}$ 1.0 $GeV/c$.)
International Nuclear Information System (INIS)
Salati, Pierre.
1980-01-01
The purpose of this work is to analyse the structure functions produced by a deep inelastic scattering experiment of muons upon a hadronic target. A non perturbative model is tested. In order to chek the quantum chromodynamics, the moments and the Altarelli-Parisi equations are used. The main result is the scaling parameter lambda [fr
International Nuclear Information System (INIS)
Safronov, A.N.
1983-01-01
A system of nonsingular integral equations is formulated for calculation of the partial-wave amplitudes of hadron-hadron scattering in the region of low and intermediate energies with allowance for the meson and quark-gluon degrees of freedom. The quark-gluon degrees of freedom are taken into account in the framework of the model of composite quark bags, and the meson degrees of freedom by the methods of relativistic quantum field theory. It is shown that inclusion of the quark-gluon degrees of freedom leads to suppression of meson exchange effects, for the most part exchanges of heavy mesons (rho,ω). The method is applied to the calculation of the 3 S 1 , 1 S 0 , 3 P 0 , 3 P 1 , and 1 P 1 phase shifts of nucleon-nucleon scattering in the range of incident-nucleon energies T = 0--1050 MeV, as well as the S-wave scattering lengths and effective ranges
Aaron, F.D.; Alexa, C.; Alimujiang, K.; Andreev, V.; Antunovic, B.; Asmone, A.; Backovic, S.; Baghdasaryan, A.; Barrelet, E.; Bartel, W.; Begzsuren, K.; Belousov, A.; Bizot, J.C.; Boudry, V.; Bozovic-Jelisavcic, I.; Bracinik, J.; Brandt, G.; Brinkmann, M.; Brisson, V.; Bruncko, D.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A.J.; Cantun Avila, K.B.; Cassol-Brunner, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Cholewa, A.; Contreras, J.G.; Coughlan, J.A.; Cozzika, G.; Cvach, J.; Dainton, J.B.; Daum, K.; Deak, M.; de Boer, Y.; Delcourt, B.; Del Degan, M.; Delvax, J.; De Wolf, E.A.; Diaconu, C.; Dodonov, V.; Dossanov, A.; Dubak, A.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eliseev, A.; Elsen, E.; Falkiewicz, A.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Fischer, D.-J.; Fleischer, M.; Fomenko, A.; Gabathuler, E.; Gayler, J.; Ghazaryan, Samvel; Glazov, A.; Glushkov, I.; Goerlich, L.; Gogitidze, N.; Gouzevitch, M.; Grab, C.; Greenshaw, T.; Grell, B.R.; Grindhammer, G.; Habib, S.; Haidt, D.; Helebrant, C.; Henderson, R.C.W.; Hennekemper, E.; Henschel, H.; Herbst, M.; Herrera, G.; Hildebrandt, M.; Hiller, K.H.; Hoffmann, D.; Horisberger, R.; Hreus, T.; Jacquet, M.; Janssen, M.E.; Janssen, X.; Jonsson, L.; Jung, Andreas Werner; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I.R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Kluge, T.; Knutsson, A.; Kogler, R.; Kostka, P.; Kraemer, M.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Kruger, K.; Kutak, K.; Landon, M.P.J.; Lange, W.; Lastovicka-Medin, G.; Laycock, P.; Lebedev, A.; Leibenguth, G.; Lendermann, V.; Levonian, S.; Li, G.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lytkin, L.; Makankine, A.; Malinovski, E.; Marage, P.; Marti, Ll.; Martyn, H.-U.; Maxfield, S.J.; Mehta, A.; Meyer, A.B.; Meyer, H.; Meyer, H.; Meyer, J.; Michels, V.; Mikocki, S.; Milcewicz-Mika, I.; Moreau, F.; Morozov, A.; Morris, J.V.; Mozer, Matthias Ulrich; Mudrinic, M.; Muller, K.; Murin, P.; Naumann, Th.; Newman, P.R.; Niebuhr, C.; Nikiforov, A.; Nowak, G.; Nowak, K.; Nozicka, M.; Olivier, B.; Olsson, J.E.; Osman, S.; Ozerov, D.; Palichik, V.; Panagoulias, I.; Pandurovic, M.; Papadopoulou, Th.; Pascaud, C.; Patel, G.D.; Pejchal, O.; Perez, E.; Petrukhin, A.; Picuric, I.; Piec, S.; Pitzl, D.; Placakyte, R.; Pokorny, B.; Polifka, R.; Povh, B.; Preda, T.; Radescu, V.; Rahmat, A.J.; Raicevic, N.; Raspiareza, A.; Ravdandorj, T.; Reimer, P.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rotaru, M.; Ruiz Tabasco, J.E.; Rurikova, Z.; Rusakov, S.; Salek, D.; Sankey, D.P.C.; Sauter, M.; Sauvan, E.; Schmitt, S.; Schoeffel, L.; Schoning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shaw-West, R.N.; Shtarkov, L.N.; Shushkevich, S.; Sloan, T.; Smiljanic, Ivan; Soloviev, Y.; Sopicki, P.; South, D.; Spaskov, V.; Specka, Arnd E.; Staykova, Z.; Steder, M.; Stella, B.; Stoicea, G.; Straumann, U.; Sunar, D.; Sykora, T.; Tchoulakov, V.; Thompson, G.; Thompson, P.D.; Toll, T.; Tomasz, F.; Tran, T.H.; Traynor, D.; Trinh, T.N.; Truol, P.; Tsakov, I.; Tseepeldorj, B.; Turnau, J.; Urban, K.; Valkarova, A.; Vallee, C.; Van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Vinokurova, S.; Volchinski, V.; von den Driesch, M.; Wegener, D.; Wissing, Ch.; Wunsch, E.; Zacek, J.; Zalesak, J.; Zhang, Z.; Zhokin, A.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.; Zus, R.
2009-01-01
A first measurement is presented of the charge asymmetry in the hadronic final state from the hard interaction in deep-inelastic ep neutral current scattering at HERA. The measurement is performed in the range of negative squared four momentum transfer 100hadron and parton level.
International Nuclear Information System (INIS)
Aaron, F.D.; Alexa, C.
2009-06-01
A first measurement is presented of the charge asymmetry in the hadronic final state from the hard interaction in deep-inelastic ep neutral current scattering at HERA. The measurement is performed in the range of negative squared four momentum transfer 100 2 2 . The difference between the event normalised distributions of the scaled momentum, x p , for positively and negatively charged particles, measured in the current region of the Breit frame, is studied together with its evolution as a function of Q. The results are compared to Monte Carlo models at the hadron and parton level. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Airapetian, A. [Giessen Univ. (Germany). Physikalisches Inst.; Michigan Univ., Ann Arbor, MI (United States). Randall Laboratory of Physics; Akopov, N. [Yerevan Physics Institute (Armenia); Akopov, Z. [DESY Hamburg (DE)] (and others)
2012-04-15
The azimuthal cos {phi} and cos 2{phi} modulations of the distribution of hadrons produced in unpolarized semi-inclusive deep-inelastic scattering of electrons and positrons off hydrogen and deuterium targets have been measured in the Hermes experiment. For the first time these modulations were determined in a four-dimensional kinematic space for positively and negatively charged pions and kaons separately, as well as for unidentified hadrons. These azimuthal dependences are sensitive to the transverse motion and polarization of the quarks within the nucleon via, e.g., the Cahn, Boer-Mulders and Collins effects.
International Nuclear Information System (INIS)
Gauron, P.; Nicolescu, B.
1992-06-01
It is shown both on general and phenomenological grounds, why the ρ-parameter (the ratio of the real over the imaginary part of the forward hadron amplitude) is the most suitable one for exploring Odderon effects in the present energy range. An almost model-independent analysis of the experimental data by taking into account the analytical constraints and the assumption of maximality is performed. Using the maximal Odderon approach as a guide, the following constrain at √s= 546 GeV is established: ρ ( p-bar) p pp T >σ p -bar p T relation exists. (R.P.) 14 refs., 3 figs
Hadron-pair production on transversely polarized targets in semi-inclusive deep inelastic scattering
Energy Technology Data Exchange (ETDEWEB)
Braun, Christopher
2014-07-29
Nucleons such as protons and neutrons are composite objects made of quarks, which are bound together by the strong force via the exchange of gluons. The probability of finding a quark of flavor q carrying the momentum fraction x of the fast moving parent nucleon is described by a parton distribution function (PDF) f{sub 1}{sup q}(x), the number density. The spin, an intrinsic angular momentum of elementary particles such as quarks but also of composite objects like nucleons, couples with magnetic fields, which allows one to align it. Taking into account this additional parameter, the spin, the scheme of PDFs in leading twist is expanded by the helicity distribution g{sub 1}{sup q}(x) and the transversity distribution h{sub 1}{sup q}(x). The first distribution covers the case where the nucleon and the quark are longitudinally polarized, while a transverse polarization is taken into account by the latter. A tool for the investigation of the PDFs is inclusive deep inelastic scattering (DIS) of electro-magnetic probes off (un)polarized nucleons at fixed-target experiments. This only gives access to f{sub 1}{sup q}(x) and g{sub 1}{sup q}(x), while the chiral-odd nature of the transversity distribution prevents a measurement without detecting the final hadronic states. However, h{sub 1}{sup q}(x) can be observed in semi-inclusive DIS (SIDIS) in combination with another chiral-odd function like the dihadron fragmentation function H{sub 1} {sup angle} {sup q} in the production of a hadron-pair. The resulting experimental challenge is the reason why f{sub 1}{sup q}(x) and g{sub 1}{sup q}(x) have been investigated for almost four decades, while h{sub 1}{sup q}(x) is still subject to recent measurements and analyses. The 160 GeV/c polarized muon beam of CERN's M2 beamline allows the COMPASS experiment to investigate spin effects using polarized solid-state targets. Since the year 2002 COMPASS has collected unique data sets on transversely polarized targets of lithium
The Hadronic Final State in Deep Inelastic ep Scattering at Low Bjorken-x at HERA
International Nuclear Information System (INIS)
Goerlich, L.M.
2006-01-01
The electron-proton collider HERA with centre of mass system energy of about 300 GeV has extended the available kinematic regime in deep inelastic scattering to low values of Bjorken-x (10 -5 -10 -3 ) and made possible studies of the QCD dynamics in this region. The processes in which partons carry a very small fraction of the proton momentum may show deviations from the standard DGLAP dynamics and it is believed that their correct description is provided by the BFKL evolution formalism. Low x phenomena have been initially studied with the HERA data on F 2 structure function and later with more exclusive measurements of the hadronic final state. In this report recent results of these studies and especially dedicated measurements of jets and π 0 mesons, produced close to the proton remnant, are reviewed. The data are used to discriminate between QCD models with different parton evolution approximations. For completeness, measurements at e + e - and p-p colliders sensitive to the BFKL dynamics are also described. (author)
International Nuclear Information System (INIS)
Bugrij, G.; Jenkovsky, L.; Martynov, E.
1994-01-01
These Proceedings contain the contributions to the Workshop HADRONS-94,held in Uzhgorod between September 7-11,1994. They covers the topics: - elastic and diffractive scattering of hadrons and nuclei; -small-x and spin physics; - meson and baryon spectroscopy; - dual and string models; - collective properties of the strongly interacting matter
Energy Technology Data Exchange (ETDEWEB)
Bugrij, G; Jenkovsky, L; Martynov, E [eds.
1994-12-31
These Proceedings contain the contributions to the Workshop HADRONS-94,held in Uzhgorod between September 7-11,1994. They covers the topics: - elastic and diffractive scattering of hadrons and nuclei; -small-x and spin physics; - meson and baryon spectroscopy; - dual and string models; - collective properties of the strongly interacting matter.
Charge structure of the hadronic final state in deep-inelastic muon-nucleon scattering
International Nuclear Information System (INIS)
Arneodo, M.; Ferrero, M.I.; Peroni, C.; Beaufays, J.; Jacholkowska, A.; Kellner, G.; Osborne, A.M.; Bee, C.P.; Bird, I.; Coughlan, J.; Sloan, T.; Braun, H.; Brueck, H.; Drees, J.; Edwards, A.; Krueger, J.; Montgomery, H.E.; Peschel, H.; Pietrzyk, U.; Poetsch, M.; Schneider, A.; Combley, F.; Foster, J.; Whalley, M.; Wheeler, S.; Dreyer, T.; Ernst, T.; Haas, J.; Kabuss, E.M.; Landgraf, U.; Mohr, W.; Rith, K.; Schlagboehmer, A.; Schroeder, T.; Stier, H.E.; Wallucks, W.; Figiel, J.; Gajewski, J.; Janata, F.; Poensgen, B.; Schiemann, H.; Studt, M.; Torre, A. de la; Geddes, N.; Johnson, A.S.; Loken, J.; Long, K.; Renton, P.; Taylor, G.N.; Williams, W.S.C.; Grard, F.; Windmolders, R.
1988-01-01
The general charge properties of the hadronic final state produced in μ + p and μ + d interactions at 280 GeV are investigated. Quark charge retention and local charge compensation is observed. The ratio F 2 n /F 2 p of the neutron to proton structure function is derived from the measurement of the average hadronic charge in μd interactions. (orig.)
Muon g-2 theory. The hadronic part
International Nuclear Information System (INIS)
Jegerlehner, Fred
2017-04-01
I present a status report of the hadronic vacuum polarization effects for the muon g-2, to be considered as an update of an earlier paper (F. Jegerlehner, 2016). The update concerns recent new inclusive R measurements from KEDR in the energy range 1.84 to 3.72 GeV. For the leading order contributions I find a had(1) μ =(688.07±4.14)[688.77±3.38] x 10 -10 based on e + e - data [incl. τ data], a had(2) μ =(-9.93±0.07) x 10 -10 (NLO) and a had(3) μ =(1.22±0.01) x 10 -10 (NNLO). Collecting recent progress in the hadronic light-by-light scattering I adopt π 0 ,η,η ' [95±12]+axial-vector[8± 3]+scalar [-6 ±1]+π,K loops[-20±5]+quark loops[22±4]+tensor [1±0]+NLO[3±2] which yields a (6) μ (lbl,had)=(103±29) x 10 -11 . With these updates I find a exp μ -a the μ =(31.3±7.7) x 10 -10 a 4.1σ deviation. Recent lattice QCD results and future prospects to improve hadronic contributions are discussed.
Scattering, diffraction and multiparticle production on hadron and nuclei at high energy
International Nuclear Information System (INIS)
Ter-Martirosyan, K.A.; Zoller, V.R.
1988-01-01
The cross sections for different types of interactions of hadronic with hadrons and nuclei at high energy are obtained in the simple form in the supercritical pomeron theory. Diffraction desintegration (DD) of hadrons both in the intermediate states, between rescatterings on pomerons, and in the final states is taken into account. With the same accuracy the cross sections δ n for production of n pomeron jets on hadrons and nuclei are also obtained. They determine the whole dynamics of the multiple particle productions, i.e. the spectra and multiplicities of produced particles, the cross sections for DD of colliding hadrons and nucleons inside the target nuclei. The numerical results for δ tot , δ el and for dδ el /dp tr 2 with the set of the pomeron and f, ω-reggeons pole parameters obtained early are presented. 19 refs.; 6 figs
Energy Technology Data Exchange (ETDEWEB)
Hicks, R.G.
1978-01-01
An experiment was performed to study muon-proton scattering at an incident energy of 225 GeV and a total effective flux of 4.3 x 10/sup 10/ muons. This experiment is able to detect charged particles in coincidence with the scattered muon in the forward hemisphere, and results are reported for the neutral strange particles K/sub s//sup 0/ and ..lambda../sup 0/ decaying into two charged particles. Within experimental limits the masses and lifetimes of these particles are consistent with previous measurements. The distribution of hadrons produced in muon scattering is determined, measuring momentum components parallel and transverse to the virtual photon direction, and these distributions are compared to other high energy experiments involving the scattering of pions, protons, and neutrinos from protons. Structure functions for hadron production and particle ratios are calculated. No azimuthal dependence is observed, and lambda production does not appear to be polarized. The physical significance of the results is discussed within the framework of the quark-parton model. 29 references.
Energy Technology Data Exchange (ETDEWEB)
Nicolescu, Basarab [LPNHE, Unite de Recherche des Universites Paris 6 et Paris 7, associee au CNRS, Theory Group, Universite Pierre et Marie Curie, 4 Place Jussieu, 75252 Paris Cedex 05 (France)
2004-07-01
We consider several classes of analytic parametrizations of hadronic scattering amplitudes (the COMPETE analysis), and compare their predictions to all available forward data (pp, {pi}p, Kp, {gamma}p, {gamma}{gamma}, {sigma}p). Although these parametrizations are very close for {radical}s {>=} 9 GeV, it turns out that they differ markedly at low energy, where a universal Pomeron term {approx} ln{sup 2} s enables one to extend the fit down to {radical}s = 4 GeV. We present predictions on the total cross sections and on the ratio of the real part to the imaginary part of the elastic amplitude ({rho} parameter) for present and future pp colliders, and on total cross sections for {gamma}p {yields} hadrons at cosmic-ray energies and for it{gamma}{gamma} {yields} hadrons up to {radical}s = 1 TeV. The ln{sup 2} s behaviour of total cross sections, first obtained by Heisenberg 50 years ago, receives now increased interest both on phenomenological and theoretical levels. We present a modification of the Heisenberg's model in connection with the presence of glueballs and we show that it leads to a realistic description of all existing hadron total cross-sections data, in agreement with the COMPETE analysis.
Probing electroweak gauge boson scattering with the ATLAS detector at the large hadron collider
International Nuclear Information System (INIS)
Anger, Philipp
2014-01-01
Electroweak gauge bosons as central components of the Standard Model of particle physics are well understood theoretically and have been studied with high precision at past and present collider experiments. The electroweak theory predicts the existence of a scattering process of these particles consisting of contributions from triple and quartic bosonic couplings as well as Higgs boson mediated interactions. These contributions are not separable in a gauge invariant way and are only unitarized in the case of a Higgs boson as it is described by the Standard Model. The process is tied to the electroweak symmetry breaking which introduces the longitudinal modes for the massive electroweak gauge bosons. A study of this interaction is also a direct verification of the local gauge symmetry as one of the fundamental axioms of the Standard Model. With the start of the Large Hadron Collider and after collecting proton-proton collision data with an integrated luminosity of 20.3 fb -1 at a center-of-mass energy of √(s)=8 TeV with the ATLAS detector, first-ever evidence for this process could be achieved in the context of this work. A study of leptonically decaying W ± W ± jj, same-electric-charge diboson production in association with two jets resulted in an observation of the electroweak W ± W ± jj production with same electric charge of the W bosons, inseparably comprising W ± W ± →W ± W ± electroweak gauge boson scattering contributions, with a significance of 3.6 standard deviations. The measured production cross section is in agreement with the Standard Model prediction. In the course of a study for leptonically decaying WZ productions, methods for background estimation, the extraction of systematic uncertainties and cross section measurements were developed. They were extended and applied to the WZjj final state whereof the purely electroweakly mediated contribution is intrinsically tied to the scattering of all Standard Model electroweak gauge bosons: W
Evidence for light-by-light scattering in heavy-ion collisions with the ATLAS detector at the LHC
Czech Academy of Sciences Publication Activity Database
Aaboud, M.; Aad, G.; Abbott, B.; Chudoba, Jiří; Hejbal, Jiří; Hladík, Ondřej; Jakoubek, Tomáš; Kepka, Oldřich; Kupčo, Alexander; Kůs, Vlastimil; Lokajíček, Miloš; Lysák, Roman; Marčišovský, Michal; Mikeštíková, Marcela; Němeček, Stanislav; Penc, Ondřej; Šícho, Petr; Staroba, Pavel; Svatoš, Michal; Taševský, Marek
2017-01-01
Roč. 13, č. 9 (2017), s. 852-868 ISSN 1745-2473 Institutional support: RVO:68378271 Keywords : ATLAS * CERN LHC Coll * background * photon * transverse momentum * quantum mechanics * field strength * planarity Subject RIV: BF - Elementary Particles and High Energy Physics OBOR OECD: Particles and field physics Impact factor: 22.806, year: 2016
International Nuclear Information System (INIS)
Dedonder, J.-P.
1979-01-01
This work is devoted to the study of elastic hadron nucleus scattering. At first, an asymptotic evaluation leads to a closed, analytic expression of the eikonal amplitude. This approximate expression displays the role and the influence of the nuclear paremeters in, e.g., p-nucleus scattering around 1 GeV. Pion-nucleus scattering around the 3-3 resonance is then studied. A 3 body model calculation (pion, bound nucleon and residual nucleus represented by a potential) allows to study the importance of binding effects in this problem dominated by the strong energy dependence of the elementary amplitude. The last part is devoted to the construction in momentum space of a realistic optical potential and its comparison with experimental data. The scalling of π + and π - on neighbouring isotopes should allow the measure of the differences between the proton and neutron distributions in nuclei [fr
Goecke, Tobias; Fischer, Christian S.; Williams, Richard
2011-10-01
We present a calculation of the hadronic vacuum polarisation (HVP) tensor within the framework of Dyson-Schwinger equations. To this end we use a well-established phenomenological model for the quark-gluon interaction with parameters fixed to reproduce hadronic observables. From the HVP tensor we compute both the Adler function and the HVP contribution to the anomalous magnetic moment of the muon, aμ. We find aμHVP = 6760 ×10-11 which deviates about two percent from the value extracted from experiment. Additionally, we make comparison with a recent lattice determination of aμHVP and find good agreement within our approach. We also discuss the implications of our result for a corresponding calculation of the hadronic light-by-light scattering contribution to aμ.
Energy Technology Data Exchange (ETDEWEB)
Goecke, Tobias [Institut fuer Theoretische Physik, Universitaet Giessen, 35392 Giessen (Germany); Fischer, Christian S., E-mail: christian.fischer@theo.physik.uni-giessen.de [Institut fuer Theoretische Physik, Universitaet Giessen, 35392 Giessen (Germany); Gesellschaft fuer Schwerionenforschung mbH, Planckstr. 1, D-64291 Darmstadt (Germany); Williams, Richard [Dept. Fisica Teorica I, Universidad Complutense, 28040 Madrid (Spain)
2011-10-13
We present a calculation of the hadronic vacuum polarisation (HVP) tensor within the framework of Dyson-Schwinger equations. To this end we use a well-established phenomenological model for the quark-gluon interaction with parameters fixed to reproduce hadronic observables. From the HVP tensor we compute both the Adler function and the HVP contribution to the anomalous magnetic moment of the muon, a{sub {mu}}. We find a{sub {mu}}{sup HVP}=6760x10{sup -11} which deviates about two percent from the value extracted from experiment. Additionally, we make comparison with a recent lattice determination of a{sub {mu}}{sup HVP} and find good agreement within our approach. We also discuss the implications of our result for a corresponding calculation of the hadronic light-by-light scattering contribution to a{sub {mu}.}
International Nuclear Information System (INIS)
Goecke, Tobias; Fischer, Christian S.; Williams, Richard
2011-01-01
We present a calculation of the hadronic vacuum polarisation (HVP) tensor within the framework of Dyson-Schwinger equations. To this end we use a well-established phenomenological model for the quark-gluon interaction with parameters fixed to reproduce hadronic observables. From the HVP tensor we compute both the Adler function and the HVP contribution to the anomalous magnetic moment of the muon, a μ . We find a μ HVP =6760x10 -11 which deviates about two percent from the value extracted from experiment. Additionally, we make comparison with a recent lattice determination of a μ HVP and find good agreement within our approach. We also discuss the implications of our result for a corresponding calculation of the hadronic light-by-light scattering contribution to a μ .
Light-by-light-type corrections to the muon anomalous magnetic moment at four-loop order
International Nuclear Information System (INIS)
Kurz, Alexander; Smirnov, Alexander V.; Smirnov, Vladimir A.
2015-08-01
The numerically dominant QED contributions to the anomalous magnetic moment of the muon stem from Feynman diagrams with internal electron loops. We consider such corrections and present a calculation of the four-loop light-by-light-type corrections where the external photon couples to a closed electron or muon loop. We perform an asymptotic expansion in the ratio of electron and muon mass and reduce the resulting integrals to master integrals which we evaluate using analytical and numerical methods. We confirm the results present in the literature which are based on different computational methods.
Anomalous decay and scattering processes of the meson
Kubis, Bastian; Plenter, Judith
2015-06-01
We amend a recent dispersive analysis of the anomalous decay process by the effects of the tensor meson, the lowest-lying resonance that can contribute in the system. While the net effects on the measured decay spectrum are small, they may be more pronounced for the analogous decay. There are nonnegligible consequences for the transition form factor, which is an important quantity for the hadronic light-by-light scattering contribution to the muon's anomalous magnetic moment. We predict total and differential cross sections, as well as a marked forward-backward asymmetry, for the crossed process , which could be measured in Primakoff reactions in the future.
Adolph, C.; Aghasyan, M.; Akhunzyanov, R.; Alexeev, M.G.; Alexeev, G.D.; Amoroso, A.; Andrieux, V.; Anfimov, N.V.; Anosov, V.; Augustyniak, W.; Austregesilo, A.; Azevedo, C.D.R.; Badelek, B.; Balestra, F.; Barth, J.; Beck, R.; Bedfer, Y.; Bernhard, J.; Bicker, K.; Bielert, E.R.; Birsa, R.; Bisplinghoff, J.; Bodlak, M.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bressan, A.; Buechele, M.; Capozza, L.; Chang, W. -C.; Chatterjee, C.; Chiosso, M.; Choi, I.; Chung, S. -U.; Cicuttin, A.; Crespo, M.L.; Curiel, Q.; Dalla Torre, S.; Dasgupta, S.S.; Dasgupta, S.; Denisov, O. Yu.; Dhara, L.; Donskov, S.V.; Doshita, N.; Duic, V.; Duennweber, W.; Dziewiecki, M.; Efremov, A.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Finger, M.; Fischer, H.; Franco, C.; von Hohenesche, N. du Fresne; Friedrich, J.M.; Frolov, V.; Fuchey, E.; Gautheron, F.; Gavrichtchouk, O.P.; Gerassimov, S.; Giordano, F.; Gnesi, I.; Gorzellik, M.; Grabmueller, S.; Grasso, A.; Grosse Perdekamp, M.; Grube, B.; Grussenmeyer, T.; Guskov, A.; Haas, F.; Hahne, D.; von Harrach, D.; Hashimoto, R.; Heinsius, F.H.; Heitz, R.; Herrmann, F.; Hinterberger, F.; Horikawa, N.; dHose, N.; Hsieh, C. -Y.; Huber, S.; Ishimoto, S.; Ivanov, A.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Joosten, R.; Joerg, P.; Kabuss, E.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu. A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koivuniemi, J.H.; Kolosov, V.N.; Kondo, K.; Koenigsmann, K.; Konorov, I.; Konstantinov, V.F.; Kotzinian, A.M.; Kouznetsov, O.M.; Kuhn, R.; Kraemer, M.; Kremser, P.; Krinner, F.; Kroumchtein, Z.V.; Kulinich, Y.; Kunne, F.; Kurek, K.; Kurjata, R.P.; Lednev, A.A.; Lehmann, A.; Levillain, M.; Levorato, S.; Lichtenstadt, J.; Longo, R.; Maggiora, A.; Magnon, A.; Makins, N.; Makke, N.; Mallot, G.K.; Marchand, C.; Marianski, B.; Martin, A.; Marzec, J.; Matousek, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.V.; Meyer, W.; Michigami, T.; Mikhailov, Yu. V.; Mikhasenko, M.; Mitrofanov, E.; Mitrofanov, N.; Miyachi, Y.; Montuenga, P.; Nagaytsev, A.; Nerling, F.; Neyret, D.; Nikolaenko, V.I.; Novy, J.; Nowak, W.-D.; Nukazuka, G.; Nunes, A.S.; Olshevsky, A.G.; Orlov, I.; Ostrick, M.; Panzieri, D.; Parsamyan, B.; Paul, S.; Peng, J. -C.; Pereira, F.; Pesek, M.; Peshekhonov, D.V.; Pierre, N.; Platchkov, S.; Pochodzalla, J.; Polyakov, V.A.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Regali, C.; Reicherz, G.; Riedl, C.; Roskot, M.; Ryabchikov, D.I.; Rybnikov, A.; Rychter, A.; Salac, R.; Samoylenko, V.D.; Sandacz, A.; Santos, C.; Sarkar, S.; Savin, I.A.; Sawada, T.; Sbrizzai, G.; Schiavon, P.; Schmidt, K.; Schmieden, H.; Schoenning, K.; Schopferer, S.; Seder, E.; Selyunin, A.; Shevchenko, O. Yu.; Steffen, D.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Smolik, J.; Sozzi, F.; Srnka, A.; Stolarski, M.; Sulc, M.; Suzuki, H.; Szabelski, A.; Szameitat, T.; Sznajder, P.; Takekawa, S.; Tasevsky, M.; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Tosello, F.; Tskhay, V.; Uhl, S.; Veloso, J.; Virius, M.; Vondra, J.; Weisrock, T.; Wilfert, M.; Windmolders, R.; ter Wolbeek, J.; Zaremba, K.; Zavada, P.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zink, A.
2017-01-10
Multiplicities of charged pions and unidentified hadrons produced in deep-inelastic scattering were measured in bins of the Bjorken scaling variable $x$, the relative virtual-photon energy $y$ and the relative hadron energy $z$. Data were obtained by the COMPASS Collaboration using a 160 GeV muon beam and an isoscalar target ($^6$LiD). They cover the kinematic domain in the photon virtuality $Q^2$ > 1(GeV/c$)^2$, $0.004 < x < 0.4$, $0.2 < z < 0.85$ and $0.1 < y < 0.7$. In addition, a leading-order pQCD analysis was performed using the pion multiplicity results to extract quark fragmentation functions.
Directory of Open Access Journals (Sweden)
C. Adolph
2017-01-01
Full Text Available Multiplicities of charged pions and charged hadrons produced in deep-inelastic scattering were measured in three-dimensional bins of the Bjorken scaling variable x, the relative virtual-photon energy y and the relative hadron energy z. Data were obtained by the COMPASS Collaboration using a 160GeV muon beam and an isoscalar target (6LiD. They cover the kinematic domain in the photon virtuality Q2>1(GeV/c2, 0.004
Azimuthal asymmetry and transverse momentum of hadrons in deep inelastic muon scattering at 490 GeV
International Nuclear Information System (INIS)
Baker, M.D.
1993-01-01
The forward charged hadrons produced in deep inelastic scattering of 490 GeV muons from deuterium were studied. The data were taken by the E665 collaboration during the 1987-1988 Fermilab fixed target run. 3 x 10 4 Events (6 x 10 4 hadrons) were collected over a large range of kinematic variables: 100 GeV 2 2 2 , 0.003 Bj Bj s ) QCD effects are expected to contribute to an azimuthal asymmetry and to an increase in the average transverse momentum. Some theoretical work in the literature concerning these effects is described and some original results are derived concerning the effects of primordial k perpendicular on the azimuthal distribution. A Monte Carlo program is described which includes these theoretical effects and models fragmentation, the detector response, and the event reconstruction. The data exhibit several surprising effects. First, the phi asymmetry in the data is independent of Q 2 , while theoretically it should be more pronounced at low Q 2 and vanish at high Q 2 . Second, the phi asymmetry is carried by the most energetic particle in each event, which the author calls the Rank 1 particle, and there is very little phi asymmetry of the other charged hadrons. Third, the phi asymmetry in the Rank 1 particle is independent of the hadron energy fraction z h . The Monte Carlo predicts a strong z h dependence and little rank dependence. Finally, the seagull plot shows an unexpected increase in transverse momentum p T for high energy hadrons (z h > 0.4) as a function of Q 2
Experimental study of single-particle inclusive hadron scattering and associated multiplicities
International Nuclear Information System (INIS)
Brenner, A.E.; Carey, D.C.; Elias, J.E.; Garbincius, P.H.; Mikenberg, G.; Polychronakos, V.A.; Aitkenhead, W.; Barton, D.S.; Brandenburg, G.W.; Busza, W.; Dobrowolski, T.; Friedman, J.I.; Kendall, H.W.; Lyons, T.; Nelson, B.; Rosenson, L.; Toy, W.; Verdier, R.; Votta, L.; Chiaradia, M.T.; DeMarzo, C.; Favuzzi, C.; Germinario, G.; Guerriero, L.; LaVopa, P.; Maggi, G.; Posa, F.; Selvaggi, G.; Spinelli, P.; Waldner, F.; Meunier, R.; Cutts, D.; Dulude, R.S.; Lanou, R.E. Jr.; Massimo, J.T.
1982-01-01
An experiment using the Fermilab single arm spectrometer (SAS) facility and an associated nonmagnetic vertex detector studied the reactions a+p→c+X where a and c were π +- , K +- , p, or p-bar. Extensive measurements were made at 100 and 175 GeV/c beam momenta with the outgoing hadrons detected in the SAS covering a kinematic range 0.12< x<1.0 and p/sub T/<1.25 GeV/c. Additional data covering a more restricted range in x were also gathered at 70 GeV/c incident momentum. In this high-statistics experiment, the identification of both the incoming and outgoing charged hadrons were made with a total of eight Cerenkov counters. New and extensive single-particle inclusive data for charged-particle production in low-p/sub T/ hadronic fragmentation are presented. The average associated charged-particle multiplicity and pseudorapidity distributions are also given
Hadronic contribution to the muon g-2: A Dyson-Schwinger perspective
Goecke, T.; Fischer, C. S.; Williams, R.
2012-04-01
We summarize our results for hadronic contributions to the anomalous magnetic moment of the muon (aμ), the one from hadronic vacuum-polarization (HVP) and the light-by-light scattering contribution (LBL), obtained from the Dyson-Schwinger equations (DSEs) of QCD. In the case of HVP we find good agreement with model independent determinations from dispersion relations for aμHV P as well as for the Adler function with deviations well below the ten percent level. From this we conclude that the DSE approach should be capable of describing aμLBL with similar accuracy. We also present results for LBL using a resonance expansion of the quark-anti-quark T-matrix. Our preliminary value is aμLBL=(217±91)×10-11.
Energy flow and transverse momentum of hadron jets produced in deep inelastic muon scattering
International Nuclear Information System (INIS)
Lubatti, H.J.
1990-12-01
Forward di-jet production observed in μp and μd interactions (Fermilab E665) is reported. The W 2 range studied, 100 2 2 , is the largest yet achieved. Results from separate analyses, one using only charged hadrons and the other using both charged and the neutral energy deposited in the EM calorimeter, are presented. Correlations with Σ|P T | ≅ E T , an event variable, are studied. An azimuthal asymmetry of the hadrons about the virtual photon is observed. 14 refs., 8 figs
Czech Academy of Sciences Publication Activity Database
Adolph, C.; Akhunzyanov, R.; Alekseev, M.; Alexandrov, Yu.; Alexeev, G. D.; Amoroso, A.; Andrieux, V.; Anosov, V. A.; Austregisilio, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Beck, R.; Bedfer, Y.; Berlin, A.; Bernhard, J.; Bertini, R.; Bicker, K.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bodlak, M.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Büchele, M.; Burtin, E.; Capozza, L.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Crespo, M.; Curiel, Q.; Dalla Torre, S.; Dasgupta, S. S.; Dasgupta, S.; Denisov, O.; Donskov, S.; Doshita, N.; Duic, V.; Dünnweber, W.; Dziewiecki, M.; Efremov, A.V.; Elia, C.; Eversheim, P.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger jr., M.; Fischer, H.; Franco, C.; Fresne von Hohenesche, N.; Friedrich, J.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Gorzellik, M.; Grabmüller, S.; Grasso, A.; Grube, B.; Guskov, A.; Guthörl, T.; Haas, F.; von Harrach, D.; Hahne, D.; Hashimoto, R.; Heinsius, F.; Herrmann, F.; Hinterberger, F.; Höppner, Ch.; Horikawa, N.; d'Hose, N.; Huber, S.; Ishimoto, S.; Ivanov, A.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Joerg, P.; Joosten, R.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.; Khokhlov, Y.; Kisselev, Y.; Klein, F.; Klimaszewski, K.; Koivuniemi, J.; Kolosov, V.; Kondo, K.; Königsmann, K.; Konorov, I.; Konstantinov, V.; Kotzinian, A.; Kouznetsov, O.; Král, Z.; Krämer, M.; Kroumchtein, Z.; Kuchinski, N.; Kunne, F.; Kurek, K.; Kurjata, R. P.; Lednev, A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G.; Marchand, C.; Martin, A.; Marzec, J.; Matoušek, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Y.; Miyachi, Y.; Nagaytsev, A.; Nagel, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.; Nový, J.; Nowak, W. D.; Nunes, A.S.; Orlov, I.; Olshevsky, A.; Ostrick, M.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pešek, M.; Peshekhonov, D.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Reicherz, G.; Rocco, E.; Rodionov, V. K.; Rondio, E.; Rychter, A.; Rossiyskaya, N. S.; Ryabchikov, D.; Samoylenko, V.; Sandacz, A.; Sarkar, S.; Savin, I.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schlütter, T.; Schmidt, A.; Schmidt, K.; Schmiden, H.; Schönning, K.; Schopferer, S.; Schott, M.; Shevchenko, O.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Sosio, S.; Sozzi, F.; Srnka, Aleš; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Szabelski, A.; Szameitat, T.; Sznajder, P.; Takekawa, S.; Ter Wolbeek, J.; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Vondra, J.; Wang, L.; Weisrock, T.; Wilfert, M.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.
2014-01-01
Roč. 886, SEP 2014 (2014), s. 1046-1077 ISSN 0550-3213 R&D Projects: GA MŠk(CZ) LO1212 Keywords : azimuthal hadron asymmetries * unpolarised nucleons * 6LiD target Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.929, year: 2014
Rapporteur talks at Singapore (deep inelastic scattering) and at Hadron 90 (conference summary)
International Nuclear Information System (INIS)
Close, F.E.
1990-11-01
This talk begins by reviewing the early years of deep inelastic scattering with particular reference to some theoretical work. Current highlights include an agreed uniform set of structure functions, polarised structure functions, possible violations of the Gottfried sum rule, deep inelastic scattering off nuclei and anticipated breakdown of naive perturbative quantum chromodynamics QCD as x → 0 at HERA. (author)
A critical discussion of the extraction of the {rho} - parameter at high energy hadron scattering
Energy Technology Data Exchange (ETDEWEB)
Nicolescu, B. [Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire
1996-12-31
A new and general method is proposed for the extraction of the semi theoretical {rho}-parameter from the raw dN/dt data. By using this method it is shown that the exponential form of the hadron amplitude in the diffraction peak at high energy is doubtful and that the value {rho} = 0.135 {+-} 0.015, extracted from the very precise UA4/2 dN/dt data at {radical}s 541 GeV, is probably wrong. (author) 4 refs.
Applicability of Martin close-quote s equations in high-energy elastic hadron scattering
International Nuclear Information System (INIS)
Kundrat, V.; Lokajicek, M.
1997-01-01
The validity region of Martin close-quote s equations enabling one to determine the t dependence of the real part of the elastic hadron amplitude from its imaginary part is critically reexamined. It can be concluded on the basis of a more precise analysis that quite unjustified and in principle incorrect physical results are obtained if the equations are used outside this region, i.e., for |t|approx-gt 0.15 GeV 2 . copyright 1997 The American Physical Society
NNLO QCD corrections to jet production at hadron colliders from gluon scattering
International Nuclear Information System (INIS)
Currie, James; Ridder, Aude Gehrmann-De; Glover, E.W.N.; Pires, João
2014-01-01
We present the next-to-next-to-leading order (NNLO) QCD corrections to dijet production in the purely gluonic channel retaining the full dependence on the number of colours. The sub-leading colour contribution in this channel first appears at NNLO and increases the NNLO correction by around 10% and exhibits a p T dependence, rising from 8% at low p T to 15% at high p T . The present calculation demonstrates the utility of the antenna subtraction method for computing the full colour NNLO corrections to dijet production at the Large Hadron Collider
Czech Academy of Sciences Publication Activity Database
Alekseev, M.; Alexakhin, V. Yu.; Alexandrov, Yu.; Alexeev, G. D.; Amoroso, A.; Austregisilio, A.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Bedfer, Y.; Bernhard, J.; Bertini, R.; Bettinelli, M.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Bravar, A.; Bressan, A.; Brona, G.; Burtin, E.; Bussa, M.; Chaberny, D.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Colantoni, M.; Crespo, M.; Dalla Torre, S.; Das, S.; Dasgupta, S. S.; Denisov, O.; Dhara, L.; Diaz, V.; Donskov, S.; Doshita, N.; Duic, V.; Dünnweber, W.; Efremov, A.V.; El Alaoui, A.; Eversheim, P.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger jr., M.; Fischer, H.; Franco, C.; Friedrich, J.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.; Gazda, R.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmüller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Haas, F.; von Harrach, D.; Hasegawa, T.; Heinsius, F.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Höppner, Ch.; d'Hose, N.; Ilgner, C.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jasinski, P.; Jegou, G.; Joosten, R.; Jouravlev, N. I.; Kabuss, E.; Kang, D.; Ketzer, B.; Khaustov, G.; Khokhlov, Y.; Kisselev, Y.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.; Kolosov, V.; Kondo, K.; Königsmann, K.; Konopka, R.; Konorov, I.; Konstantinov, V.; Korzenev, A.; Kotzinian, A.; Kouznetsov, O.; Kowalik, K.; Krämer, M.; Kral, A.; Kroumchtein, Z.; Kuhn, R.; Kunne, F.; Kurek, K.; Lauser, L.; Le Goff, J.; Lednev, A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Maggiora, A.; Maggiora, M.; Magnon, A.; Mallot, G.; Mann, A.; Marchand, C.; Martin, A.; Marzec, J.; Massmann, F.; Matsuda, T.; Meyer, W.; Michigami, T.; Mikhailov, Y.; Moinester, M.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Nassalski, J.; Negrini, S.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.; Nunes, A.S.; Olshevsky, A.; Ostrick, M.; Padee, A.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pawlukiewicz-Kaminska, B.; Perevalova, E.; Pesaro, G.; Peshekhonov, D.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.; Pontecorvo, G.; Pretz, J.; Quintans, C.; Rajotte, J.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Richter, A.; Robinet, F.; Rocco, E.; Rondio, E.; Ryabchikov, D.; Samoylenko, V.; Sandacz, A.; Santos, H.; Sapozhnikov, M.; Sarkar, S.; Savin, I.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schlütter, T.; Schmitt, L.; Schopferer, S.; Schröder, W.; Shevchenko, O.; Siebert, H.; Silva, L.; Sinha, L.; Sissakian, A.; Slunecka, M.; Smirnov, G.; Sosio, S.; Sozzi, F.; Srnka, Aleš; Stolarski, M.; Sulc, M.; Sulej, R.; Takekawa, S.; Tessaro, S.; Tessarotto, F.; Teufel, A.; Tkatchev, L.; Uhl, S.; Uman, I.; Virius, M.; Vlassov, N.; Vossen, A.; Weitzel, Q.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zhao, J.; Zhuravlev, N.; Zvyagin, A.
2010-01-01
Roč. 70, 1-2 (2010), s. 39-49 ISSN 1434-6044 R&D Projects: GA MŠk ME 492 Institutional research plan: CEZ:AV0Z20650511 Keywords : deep-inelastic-scattering * dependent structure-function * single-spin asymmetries * semiinclusive electroproduction * proton-scattering * distributions * leptoproduction * target * dis * nucleons Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.248, year: 2010
Real part of amplitude and hadron scattering cross section at superhigh energies
International Nuclear Information System (INIS)
Troshin, S.M.; Tyurin, N.E.
1987-01-01
New data on measuring the ratio of the real to imaginary part of the forward scattering amplitude: ρ pp-bar (√s=546 GeV)=0.24±0.04 have been considered. This result is shown to agree with the behaviour of σ tot (s), predicted by the U-matrix model. A possibility of transition to antishadow scattering mode at superhigh energies is stated
Self-consistent theory of hadron-nucleus scattering. Application to pion physics
International Nuclear Information System (INIS)
Johnson, M.B.
1980-01-01
The requirement of using self-consistent amplitudes to evaluate microscopically the scattering of strongly interacting particles from nuclei is developed. Application of the idea to a simple model of pion-nucleus scattering is made. Numerical results indicate that the expansion of the optical potential converges when evaluated in terms of fully self-consistent quantities. A comparison of the results to a recent determination of the spreading interaction in the phenomenological isobar-hole model shows that the theory accounts for the sign and magnitude of the real and imaginary part of the spreading interaction with no adjusted parameters. The self-consistnt theory has a strong density dependence, and the consequences of this for pion-nucleus scattering are discussed. 18 figures, 1 table
HERWIG for Hadron-Hadron physics
International Nuclear Information System (INIS)
Seymour, M.H.
1993-05-01
HERWIG is a general-purpose particle physics event generator, which includes the simulation of any combination of hard lepton, hadron or photon scattering and soft hadron-hadron collisions in one package. It uses the parton-shower approach for initial-state and final-state QCD radiation, including colour coherence effects and azimuthal correlations both within and between jets. This article describes HERWIG version 5.6, and gives a brief review of the physics underlying HERWIG, with particular emphasis on hadron-hadron collisions. Details are given of the input and control parameters used by the program
Measurement of the Hadronic Cross-Section for the Scattering of Two Virtual Photons at LEP
Abbiendi, G.; Akesson, P.F.; Alexander, G.; Allison, John; Anagnostou, G.; Anderson, K.J.; Arcelli, S.; Asai, S.; Axen, D.; Azuelos, G.; Bailey, I.; Barberio, E.; Barlow, R.J.; Batley, R.J.; Behnke, T.; Bell, Kenneth Watson; Bell, P.J.; Bella, G.; Bellerive, A.; Bethke, S.; Biebel, O.; Bloodworth, I.J.; Boeriu, O.; Bock, P.; Bohme, J.; Bonacorsi, D.; Boutemeur, M.; Braibant, S.; Brigliadori, L.; Brown, Robert M.; Burckhart, H.J.; Cammin, J.; Carnegie, R.K.; Caron, B.; Carter, A.A.; Carter, J.R.; Chang, C.Y.; Charlton, David G.; Clarke, P.E.L.; Clay, E.; Cohen, I.; Couchman, J.; Csilling, A.; Cuffiani, M.; Dado, S.; Dallavalle, G.Marco; Dallison, S.; De Roeck, A.; De Wolf, E.A.; Dervan, P.; Desch, K.; Dienes, B.; Dixit, M.S.; Donkers, M.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I.P.; Etzion, E.; Fabbri, F.; Feld, L.; Ferrari, P.; Fiedler, F.; Fleck, I.; Ford, M.; Frey, A.; Furtjes, A.; Futyan, D.I.; Gagnon, P.; Gary, J.W.; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Glenzinski, D.; Goldberg, J.; Graham, K.; Gross, E.; Grunhaus, J.; Gruwe, M.; Gunther, P.O.; Gupta, A.; Hajdu, C.; Hamann, M.; Hanson, G.G.; Harder, K.; Harel, A.; Harin-Dirac, M.; Hauschild, M.; Hauschildt, J.; Hawkes, C.M.; Hawkings, R.; Hemingway, R.J.; Hensel, C.; Herten, G.; Heuer, R.D.; Hill, J.C.; Hoffman, Kara Dion; Homer, R.J.; Horvath, D.; Hossain, K.R.; Howard, R.; Huntemeyer, P.; Igo-Kemenes, P.; Ishii, K.; Jawahery, A.; Jeremie, H.; Jones, C.R.; Jovanovic, P.; Junk, T.R.; Kanaya, N.; Kanzaki, J.; Karapetian, G.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Keeler, R.K.; Kellogg, R.G.; Kennedy, B.W.; Kim, D.H.; Klein, K.; Klier, A.; Kluth, S.; Kobayashi, T.; Kobel, M.; Kokott, T.P.; Komamiya, S.; Kowalewski, Robert V.; Kramer, T.; Kress, T.; Krieger, P.; von Krogh, J.; Krop, D.; Kuhl, T.; Kupper, M.; Kyberd, P.; Lafferty, G.D.; Landsman, H.; Lanske, D.; Lawson, I.; Layter, J.G.; Leins, A.; Lellouch, D.; Letts, J.; Levinson, L.; Lillich, J.; Littlewood, C.; Lloyd, S.L.; Loebinger, F.K.; Long, G.D.; Losty, M.J.; Lu, J.; Ludwig, J.; Macchiolo, A.; Macpherson, A.; Mader, W.; Marcellini, S.; Marchant, T.E.; Martin, A.J.; Martin, J.P.; Martinez, G.; Masetti, G.; Mashimo, T.; Mattig, Peter; McDonald, W.John; McKenna, J.; McMahon, T.J.; McPherson, R.A.; Meijers, F.; Mendez-Lorenzo, P.; Menges, W.; Merritt, F.S.; Mes, H.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D.J.; Moed, S.; Mohr, W.; Mori, T.; Mutter, A.; Nagai, K.; Nakamura, I.; Neal, H.A.; Nisius, R.; O'Neale, S.W.; Oh, A.; Okpara, A.; Oreglia, M.J.; Orito, S.; Pahl, C.; Pasztor, G.; Pater, J.R.; Patrick, G.N.; Pilcher, J.E.; Pinfold, J.; Plane, David E.; Poli, B.; Polok, J.; Pooth, O.; Przybycien, M.; Quadt, A.; Rabbertz, K.; Rembser, C.; Renkel, P.; Rick, H.; Rodning, N.; Roney, J.M.; Rosati, S.; Roscoe, K.; Rozen, Y.; Runge, K.; Rust, D.R.; Sachs, K.; Saeki, T.; Sahr, O.; Sarkisyan, E.K.G.; Sbarra, C.; Schaile, A.D.; Schaile, O.; Scharff-Hansen, P.; Schroder, Matthias; Schumacher, M.; Schwick, C.; Scott, W.G.; Seuster, R.; Shears, T.G.; Shen, B.C.; Shepherd-Themistocleous, C.H.; Sherwood, P.; Skuja, A.; Smith, A.M.; Snow, G.A.; Sobie, R.; Soldner-Rembold, S.; Spagnolo, S.; Spano, F.; Sproston, M.; Stahl, A.; Stephens, K.; Strom, David M.; Strohmer, R.; Stumpf, L.; Surrow, B.; Tarem, S.; Tasevsky, M.; Taylor, R.J.; Teuscher, R.; Thomas, J.; Thomson, M.A.; Torrence, E.; Toya, D.; Trefzger, T.; Tricoli, A.; Trigger, I.; Trocsanyi, Z.; Tsur, E.; Turner-Watson, M.F.; Ueda, I.; Ujvari, B.; Vachon, B.; Vollmer, C.F.; Vannerem, P.; Verzocchi, M.; Voss, H.; Vossebeld, J.; Waller, D.; Ward, C.P.; Ward, D.R.; Watkins, P.M.; Watson, A.T.; Watson, N.K.; Wells, P.S.; Wengler, T.; Wermes, N.; Wetterling, D.; Wilson, G.W.; Wilson, J.A.; Wyatt, T.R.; Yamashita, S.; Zacek, V.; Zer-Zion, D.
2001-01-01
The interaction of virtual photons is investigated using the reaction e+e- -> e+e- hadrons based on data taken by the OPAL experiment at e+e- centre-of-mass energies sqrt(s_ee)=189-209 GeV, for W>5 GeV and at an average Q^2 of 17.9 GeV^2. The measured cross-sections are compared to predictions of the Quark Parton Model (QPM), to the Leading Order QCD Monte Carlo model PHOJET to the NLO prediction for the reaction e+e- -> e+e-qqbar, and to BFKL calculations. PHOJET, NLO e+e- -> e+e-qqbar, and QPM describe the data reasonably well, whereas the cross-section predicted by a Leading Order BFKL calculation is too large.
Tannenbaum, M. J.
2018-05-01
A revolution in elementary particle physics occurred during the period from the ICHEP1968 to the ICHEP1982 with the advent of the parton model from discoveries in Deeply Inelastic electron-proton Scattering at SLAC, neutrino experiments, hard-scattering observed in p+p collisions at the CERN ISR, the development of QCD, the discovery of the J/ Ψ at BNL and SLAC and the clear observation of high transverse momentum jets at the CERN SPS p¯ + p collider. These and other discoveries in this period led to the acceptance of QCD as the theory of the strong interactions. The desire to understand nuclear physics at high density such as in neutron stars led to the application of QCD to this problem and to the prediction of a Quark-Gluon Plasma (QGP) in nuclei at high energy density and temperatures. This eventually led to the construction of the Relativistic Heavy Ion Collider (RHIC) at BNL to observe superdense nuclear matter in the laboratory. This article discusses how experimental methods and results which confirmed QCD at the first hadron collider, the CERN ISR, played an important role in experiments at the first heavy ion collider, RHIC, leading to the discovery of the QGP as a perfect liquid as well as discoveries at RHIC and the LHC which continue to the present day.
International Nuclear Information System (INIS)
Maltman, K.
1998-01-01
Using the framework of effective chiral Lagrangians, we show that, in order to correctly implement electromagnetism (EM), as generated from the Standard Model, into effective hadronic theories (such as meson-exchange models) it is insufficient to consider only graphs in the low-energy effective theory containing explicit photon lines. The Standard Model requires the presence of contact interactions in the effective theory which are electromagnetic in origin, but which involve no photons in the effective theory. We illustrate the problems which can result from a ''standard'' EM subtraction: i.e., from assuming that removing all contributions in the effective theory generated by graphs with explicit photon lines fully removes EM effects, by considering the case of the s-wave ππ scattering lengths. In this case it is shown that such a subtraction procedure would lead to the incorrect conclusion that the strong interaction isospin-breaking contributions to these quantities were large when, in fact, they are known to vanish at leading order in m d -m u . The leading EM contact corrections for the channels employed in the extraction of the I=0,2 s-wave ππ scattering lengths from experiment are also evaluated. (orig.)
International Nuclear Information System (INIS)
Bluemlein, J.
1993-08-01
The possibilities to measure structure functions, to extract parton distributions, and to measure α s and Λ QCD in current and future high energy deep inelastic scattering experiments are reviewed. A comparison is given for experiments at HERA, an ep option at LEP xLHC, and a high energy neutrino experiment. (orig.)
Muon g-2 theory. The hadronic part
Energy Technology Data Exchange (ETDEWEB)
Jegerlehner, Fred [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)
2017-04-15
I present a status report of the hadronic vacuum polarization effects for the muon g-2, to be considered as an update of an earlier paper (F. Jegerlehner, 2016). The update concerns recent new inclusive R measurements from KEDR in the energy range 1.84 to 3.72 GeV. For the leading order contributions I find a{sup had(1)}{sub μ}=(688.07±4.14)[688.77±3.38] x 10{sup -10} based on e{sup +}e{sup -} data [incl. τ data], a{sup had(2)}{sub μ}=(-9.93±0.07) x 10{sup -10} (NLO) and a{sup had(3)}{sub μ}=(1.22±0.01) x 10{sup -10} (NNLO). Collecting recent progress in the hadronic light-by-light scattering I adopt π{sup 0},η,η{sup '}[95±12]+axial-vector[8± 3]+scalar [-6 ±1]+π,K loops[-20±5]+quark loops[22±4]+tensor [1±0]+NLO[3±2] which yields a{sup (6)}{sub μ}(lbl,had)=(103±29) x 10{sup -11}. With these updates I find a{sup exp}{sub μ}-a{sup the}{sub μ}=(31.3±7.7) x 10{sup -10} a 4.1σ deviation. Recent lattice QCD results and future prospects to improve hadronic contributions are discussed.
Andreopoulos, C; Bordoni, S; Boyd, S; Brailsford, D; Brice, S; Catanesi, G; Chen-Wishart, Z; Denner, P; Dunne, P; Giganti, C; Gonzalez Diaz, D; Haigh, J; Hamacher-Baumann, P; Hallsjo, S; Hayato, Y; Irastorza, I; Jamieson, B; Kaboth, A; Korzenev, A; Kudenko, Y; Leyton, M; Luk, K-B; Ma, W; Mahn, K; Martini, M; McCauley, N; Mermod, P; Monroe, J; Mosel, U; Nichol, R; Nieves, J; Nonnenmacher, T; Nowak, J; Parker, W; Raaf, J; Rademacker, J; Radermacher, T; Radicioni, E; Roth, S; Saakyan, R; Sanchez, F; Sgalaberna, D; Shitov, Y; Sobczyk, J; Soler, F; Touramanis, C; Valder, S; Walding, J; Ward, M; Wascko, M; Weber, A; Yokoyama, M; Zalewska, A; Ziembicki, M
2017-01-01
We propose to perform new measurements of proton and pion scattering on argon using a prototype High Pressure gas Time Projection Chamber (HPTPC) detector, and by doing so to develop the physics case for, and the technological readiness of, an HPTPC as a neutrino detector for accelerator neutrino oscillation searches. The motivation for this work is to improve knowledge of final state interactions, in order to ultimately achieve 1-2% systematic error on neutrino-nucleus scattering for oscillation measurements at 0.6 GeV and 2.5 GeV neutrino energy, as required for the Charge-Parity (CP) violation sensitivity projections by the Hyper-Kamiokande experiment (Hyper-K) and the Deep Underground Neutrino Experiment (DUNE). The final state interaction uncertainties in neutrino-nucleus interactions dominate cross-section systematic errors, currently 5–10% at these energies, and therefore R&D is needed to explore new approaches to achieve this substantial improvement.
Directory of Open Access Journals (Sweden)
Ikeda Yoichi
2018-01-01
On the basis of the HAL QCD method, the structure of the tetraquark candidate Zc(3900, which was experimentally reported in e+e- collisions, is studied by the s-wave two-meson coupled-channel scattering. The results show that the Zc(3900 is not a conventional resonance but a threshold cusp. A semi-phenomenological analysis with the coupled-channel interaction to the experimentally observed decay mode is also presented to confirm the conclusion.
Energy Technology Data Exchange (ETDEWEB)
Socher, Felix
2016-07-15
high centre-of-mass energies and luminosities to study these processes successfully. The Large Hadron Collider (LHC) at CERN is a circular proton-proton collider equipped to supply a suitable environment for such studies with the colliding protons being the sources for the scattering of massive electroweak gauge bosons. The dataset collected in 2012 by the ATLAS detector at the LHC with a total luminosity of 20.3 fb{sup -1} and a centre-of-mass energy of 8 TeV is analysed in this work. The elastic scattering process WZ → WZ is studied due to its clean signal properties. It provides a complementary measurement to W{sup ±}W{sup ±}→W{sup ±}W{sup ±} which reported the first significant evidence for massive electroweak gauge boson scattering. Given the current data, WZ→WZ scattering is not observed with large significantly. A cross section upper limit of 2.5 fb at 95% confidence level is measured, compatible with the cross section of 0.54 fb predicted by the Standard Model. In addition, distributions for several observables sensitive to electroweak gauge boson scattering are unfolded, removing effects caused by the measuring process. Physics beyond the Standard Model is probed in the framework of the electroweak chiral Lagrangian which expresses the size of effects from new physics in terms of strength parameters. The two strength parameters influencing the quartic gauge couplings are constrained to -0.44<α{sub 4}<0.49 and -0.49<α{sub 5}<0.47 thus limiting the possible size of new physics contributions.
International Nuclear Information System (INIS)
Socher, Felix
2016-01-01
-of-mass energies and luminosities to study these processes successfully. The Large Hadron Collider (LHC) at CERN is a circular proton-proton collider equipped to supply a suitable environment for such studies with the colliding protons being the sources for the scattering of massive electroweak gauge bosons. The dataset collected in 2012 by the ATLAS detector at the LHC with a total luminosity of 20.3 fb"-"1 and a centre-of-mass energy of 8 TeV is analysed in this work. The elastic scattering process WZ → WZ is studied due to its clean signal properties. It provides a complementary measurement to W"±W"±→W"±W"± which reported the first significant evidence for massive electroweak gauge boson scattering. Given the current data, WZ→WZ scattering is not observed with large significantly. A cross section upper limit of 2.5 fb at 95% confidence level is measured, compatible with the cross section of 0.54 fb predicted by the Standard Model. In addition, distributions for several observables sensitive to electroweak gauge boson scattering are unfolded, removing effects caused by the measuring process. Physics beyond the Standard Model is probed in the framework of the electroweak chiral Lagrangian which expresses the size of effects from new physics in terms of strength parameters. The two strength parameters influencing the quartic gauge couplings are constrained to -0.44<α_4<0.49 and -0.49<α_5<0.47 thus limiting the possible size of new physics contributions.
International Nuclear Information System (INIS)
Dymski, T.C.
1976-01-01
For high energy scattering of pseudoscalar particles on spin 1 / 2 particles, the transition amplitude (for a given signature) is constructed as an infinite sum over spin of boson exchange graphs of the Feynman type, each of which has impact parameters up to some value R completely removed. This amplitude is advanced as a field theoretic realization of the nondiffractive component of Harari's dual absorption model. Comparing with π/sup +-/p→π/sup +-/p and π - p→π 0 n data shows that the imaginary parts of both helicity amplitudes are excellent, for either signature
Self-consistent theory of hadron-nucleus scattering. Application to pion physics
International Nuclear Information System (INIS)
Johnson, M.B.
1981-01-01
The first part of this set of two seminars will consist of a review of several of the important accomplishments made in the last few years in the field of pion-nucleus physics. Next I discuss some questions raised by these accomplishments and show that for some very natural reasons the commonly employed theoretical methods cannot be applied to answer these questions. This situation leads to the idea of self-consistency, which is first explained in a general context. The remainder of the seminars are devoted to illustrating the idea within a simple multiple-scattering model for the case of pion scattering. An evaluation of the effectiveness of the self-consistent requirment to produce a solution to the model is made, and a few of the questions raised by recent accomplishments in the field of pion physics are addressed in the model. Finally, the results of the model calculation are compared to experimental data and implications of the results discussed. (orig./HSI)
International Nuclear Information System (INIS)
Collins, P.D.B.; Martin, A.D.
1982-01-01
The mechanism of hadron scattering at high energies are reviewed in such a way as to combine the ideas of the parton model and quantum chromodynamics (QCD) with Regge theory and phenomenology. After a brief introduction to QCD and the basic features of hadron scattering data, scaling and the dimensional counting rules, the parton structure of hadrons, and the parton model for large momentum transfer processes, including scaling violations are discussed. Hadronic jets and the use of parton ideas in soft scattering processes are examined, attention being paid to Regge theory and its applications in exclusive and inclusive reactions, the relationship to parton exchange being stressed. The mechanisms of hadron production which build up cross sections, and hence the underlying Regge singularities, and the possible overlap of Regge and scaling regions are discussed. It is concluded that the key to understanding hadron reaction mechanisms seems to lie in the marriage of Regge theory with QCD. (author)
AUTHOR|(CDS)2080413; Kobel, Michael; Heinemann, Beate; Klein, Uta
Particle physics deals with the elementary constituents of our universe and their interactions. The electroweak symmetry breaking mechanism in the Standard Model of Particle Physics is of paramount importance and it plays a central role in the physics programmes of current high-energy physics experiments at the Large Hadron Collider. The study of scattering processes of massive electroweak gauge bosons provides an approach complementary to the precise measurement of the properties of the recently discovered Higgs boson. Owing to the unprecedented energies achieved in proton-proton collisions at the Large Hadron Collider and the large amount of data collected, experimental studies of these processes become feasible for the first time. Especially the scattering of two $W^{\\pm}$ bosons of identical electric charge is considered a promising process for an initial study due to its distinct experimental signature. In the course of this work, $20.3 \\, \\mathrm{fb}^{−1}$ of proton-proton collision data recorded by t...
Ultra-peripheral collisions and hadronic structure
Klein, Spencer R.
2017-11-01
Ultra-peripheral collisions are the energy frontier for photon-mediated interactions, reaching, at the Large Hadron Collider (LHC), γ - p center of mass energies five to ten times higher than at HERA and reaching γγ energies higher than at LEP. Photoproduction of heavy quarkonium and dijets in pp and pA collisions probes the gluon distribution in protons at Bjorken-x values down to 3 ×10-6, far smaller than can be otherwise studied. In AA collisions, these reactions probe the gluon distributions in heavy ions, down to x values of a few 10-5. Although more theoretical work is needed to nail down all of the uncertainties, inclusion of these data in current parton distribution function fits would greatly improve the accuracy of the gluon distributions at low Bjorken-x and low/moderate Q2. High-statistics ρ0 data probe the spatial distribution of the interaction sites; the site distribution is given by the Fourier transform of dσ / dt. After introducing UPCs, this review presents recent measurements of dilepton production and light-by-light scattering and recent data on proton and heavy nuclei structure, emphasizing results presented at Quark Matter 2017 (QM2017).
Hadron-pair production on transversely polarized targets in semi-inclusive deep inelastic scattering
Braun, Christopher
Nucleons such as protons and neutrons are composite objects made of quarks, which are bound together by the strong force via the exchange of gluons. The probability of finding a quark of flavor q carrying the momentum fraction x of the fast moving parent nucleon is described by a parton distribution function (PDF) f q 1 ( x ) , the number density. The spin, an intrinsic angular momentum of elementary particles such as quarks but also of composite objects like nucleons, couples with magnetic fields, which allows one to align it. Taking into account this additional parameter, the spin, the scheme of PDFs in leading twist is expanded by the helicity distribution g q 1 ( x ) and the transversity distribution h q 1 ( x ) . The first distribution covers the case where the nucleon and the quark are longitudinally polarized, while a transverse polarization is taken into account by the latter. A tool for the investigation of the PDFs is inclusive deep inelastic scattering (DIS) of electro- magnetic probes off (un)pola...
Density oscillations within hadrons
International Nuclear Information System (INIS)
Arnold, R.; Barshay, S.
1976-01-01
In models of extended hadrons, in which small bits of matter carrying charge and effective mass exist confined within a medium, oscillations in the matter density may occur. A way of investigating this possibility experimentally in high-energy hadron-hadron elastic diffraction scattering is suggested, and the effect is illustrated by examining some existing data which might be relevant to the question [fr
High energy hadron-hadron collisions. Annual progress report
International Nuclear Information System (INIS)
Chou, T.T.
1979-03-01
Work on high energy hadron-hadron collisions in the geometrical model, performed under the DOE Contract No. EY-76-S-09-0946, is summarized. Specific items studied include the behavior of elastic hadron scatterings at super high energies and the existence of many dips, the computation of meson radii in the geometrical model, and the hadronic matter current effects in inelastic two-body collisions
Anomalous decay and scattering processes of the η meson
International Nuclear Information System (INIS)
Kubis, Bastian; Plenter, Judith
2015-01-01
We amend a recent dispersive analysis of the anomalous η decay process η → π + π - γ by the effects of the a2 tensor meson, the lowest-lying resonance that can contribute in the πη system. While the net effects on the measured decay spectrum are small, they may be more pronounced for the analogous η' decay. There are nonnegligible consequences for the η transition form factor, which is an important quantity for the hadronic light-by-light scattering contribution to the muon's anomalous magnetic moment. We predict total and differential cross sections, as well as a marked forward.backward asymmetry, for the crossed process γπ - → π - η, which could be measured in Primakoff reactions in the future. (orig.)
Anomalous decay and scattering processes of the η meson
Energy Technology Data Exchange (ETDEWEB)
Kubis, Bastian, E-mail: kubis@hiskp.uni-bonn.de [Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, 53115, Bonn (Germany); Bethe Center for Theoretical Physics, Universität Bonn, 53115, Bonn (Germany); Plenter, Judith [Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, 53115, Bonn (Germany)
2015-06-25
We amend a recent dispersive analysis of the anomalous η decay process η→π{sup +}π{sup -}γ by the effects of the a{sub 2} tensor meson, the lowest-lying resonance that can contribute in the πη system. While the net effects on the measured decay spectrum are small, they may be more pronounced for the analogous η{sup ′} decay. There are nonnegligible consequences for the η transition form factor, which is an important quantity for the hadronic light-by-light scattering contribution to the muon’s anomalous magnetic moment. We predict total and differential cross sections, as well as a marked forward–backward asymmetry, for the crossed process γπ{sup -}→π{sup -}η, which could be measured in Primakoff reactions in the future.
Anomalous decay and scattering processes of the η meson
Energy Technology Data Exchange (ETDEWEB)
Kubis, Bastian [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik, Bonn (Germany); Universitaet Bonn, Bethe Center for Theoretical Physics, Bonn (Germany); Plenter, Judith [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik, Bonn (Germany)
2015-06-15
We amend a recent dispersive analysis of the anomalous η decay process η → π{sup +}π{sup -}γ by the effects of the a2 tensor meson, the lowest-lying resonance that can contribute in the πη system. While the net effects on the measured decay spectrum are small, they may be more pronounced for the analogous η' decay. There are nonnegligible consequences for the η transition form factor, which is an important quantity for the hadronic light-by-light scattering contribution to the muon's anomalous magnetic moment. We predict total and differential cross sections, as well as a marked forward.backward asymmetry, for the crossed process γπ{sup -} → π{sup -}η, which could be measured in Primakoff reactions in the future. (orig.)
Aaij, Roel; Adeva, Bernardo; Adinolfi, Marco; Affolder, Anthony; Ajaltouni, Ziad; Akar, Simon; Albrecht, Johannes; Alessio, Federico; Alexander, Michael; Ali, Suvayu; Alkhazov, Georgy; Alvarez Cartelle, Paula; Alves Jr, Antonio Augusto; Amato, Sandra; Amerio, Silvia; Amhis, Yasmine; An, Liupan; Anderlini, Lucio; Anderson, Jonathan; Andreassi, Guido; Andreotti, Mirco; Andrews, Jason; Appleby, Robert; Aquines Gutierrez, Osvaldo; Archilli, Flavio; d'Argent, Philippe; Artamonov, Alexander; Artuso, Marina; Aslanides, Elie; Auriemma, Giulio; Baalouch, Marouen; Bachmann, Sebastian; Back, John; Badalov, Alexey; Baesso, Clarissa; Baldini, Wander; Barlow, Roger; Barschel, Colin; Barsuk, Sergey; Barter, William; Batozskaya, Varvara; Battista, Vincenzo; Bay, Aurelio; Beaucourt, Leo; Beddow, John; Bedeschi, Franco; Bediaga, Ignacio; Bel, Lennaert; Bellee, Violaine; Belloli, Nicoletta; Belyaev, Ivan; Ben-Haim, Eli; Bencivenni, Giovanni; Benson, Sean; Benton, Jack; Berezhnoy, Alexander; Bernet, Roland; Bertolin, Alessandro; Bettler, Marc-Olivier; van Beuzekom, Martinus; Bien, Alexander; Bifani, Simone; Billoir, Pierre; Bird, Thomas; Birnkraut, Alex; Bizzeti, Andrea; Blake, Thomas; Blanc, Frédéric; Blouw, Johan; Blusk, Steven; Bocci, Valerio; Bondar, Alexander; Bondar, Nikolay; Bonivento, Walter; Borghi, Silvia; Borisyak, Maxim; Borsato, Martino; Bowcock, Themistocles; Bowen, Espen Eie; Bozzi, Concezio; Braun, Svende; Britsch, Markward; Britton, Thomas; Brodzicka, Jolanta; Brook, Nicholas; Buchanan, Emma; Burr, Christopher; Bursche, Albert; Buytaert, Jan; Cadeddu, Sandro; Calabrese, Roberto; Calvi, Marta; Calvo Gomez, Miriam; Campana, Pierluigi; Campora Perez, Daniel; Capriotti, Lorenzo; Carbone, Angelo; Carboni, Giovanni; Cardinale, Roberta; Cardini, Alessandro; Carniti, Paolo; Carson, Laurence; Carvalho Akiba, Kazuyoshi; Casse, Gianluigi; Cassina, Lorenzo; Castillo Garcia, Lucia; Cattaneo, Marco; Cauet, Christophe; Cavallero, Giovanni; Cenci, Riccardo; Charles, Matthew; Charpentier, Philippe; Chefdeville, Maximilien; Chen, Shanzhen; Cheung, Shu-Faye; Chiapolini, Nicola; Chrzaszcz, Marcin; Cid Vidal, Xabier; Ciezarek, Gregory; Clarke, Peter; Clemencic, Marco; Cliff, Harry; Closier, Joel; Coco, Victor; Cogan, Julien; Cogneras, Eric; Cogoni, Violetta; Cojocariu, Lucian; Collazuol, Gianmaria; Collins, Paula; Comerma-Montells, Albert; Contu, Andrea; Cook, Andrew; Coombes, Matthew; Coquereau, Samuel; Corti, Gloria; Corvo, Marco; Couturier, Benjamin; Cowan, Greig; Craik, Daniel Charles; Crocombe, Andrew; Cruz Torres, Melissa Maria; Cunliffe, Samuel; Currie, Robert; D'Ambrosio, Carmelo; Dall'Occo, Elena; Dalseno, Jeremy; David, Pieter; Davis, Adam; De Aguiar Francisco, Oscar; De Bruyn, Kristof; De Capua, Stefano; De Cian, Michel; De Miranda, Jussara; De Paula, Leandro; De Simone, Patrizia; Dean, Cameron Thomas; Decamp, Daniel; Deckenhoff, Mirko; Del Buono, Luigi; Déléage, Nicolas; Demmer, Moritz; Derkach, Denis; Deschamps, Olivier; Dettori, Francesco; Dey, Biplab; Di Canto, Angelo; Di Ruscio, Francesco; Dijkstra, Hans; Donleavy, Stephanie; Dordei, Francesca; Dorigo, Mirco; Dosil Suárez, Alvaro; Dossett, David; Dovbnya, Anatoliy; Dreimanis, Karlis; Dufour, Laurent; Dujany, Giulio; Durante, Paolo; Dzhelyadin, Rustem; Dziurda, Agnieszka; Dzyuba, Alexey; Easo, Sajan; Egede, Ulrik; Egorychev, Victor; Eidelman, Semen; Eisenhardt, Stephan; Eitschberger, Ulrich; Ekelhof, Robert; Eklund, Lars; El Rifai, Ibrahim; Elsasser, Christian; Ely, Scott; Esen, Sevda; Evans, Hannah Mary; Evans, Timothy; Falabella, Antonio; Färber, Christian; Farley, Nathanael; Farry, Stephen; Fay, Robert; Ferguson, Dianne; Fernandez Albor, Victor; Ferrari, Fabio; Ferreira Rodrigues, Fernando; Ferro-Luzzi, Massimiliano; Filippov, Sergey; Fiore, Marco; Fiorini, Massimiliano; Firlej, Miroslaw; Fitzpatrick, Conor; Fiutowski, Tomasz; Fohl, Klaus; Fol, Philip; Fontana, Marianna; Fontanelli, Flavio; Forshaw, Dean Charles; Forty, Roger; Frank, Markus; Frei, Christoph; Frosini, Maddalena; Fu, Jinlin; Furfaro, Emiliano; Gallas Torreira, Abraham; Galli, Domenico; Gallorini, Stefano; Gambetta, Silvia; Gandelman, Miriam; Gandini, Paolo; Gao, Yuanning; García Pardiñas, Julián; Garra Tico, Jordi; Garrido, Lluis; Gascon, David; Gaspar, Clara; Gauld, Rhorry; Gavardi, Laura; Gazzoni, Giulio; Gerick, David; Gersabeck, Evelina; Gersabeck, Marco; Gershon, Timothy; Ghez, Philippe; Gianì, Sebastiana; Gibson, Valerie; Girard, Olivier Göran; Giubega, Lavinia-Helena; Gligorov, V.V.; Göbel, Carla; Golubkov, Dmitry; Golutvin, Andrey; Gomes, Alvaro; Gotti, Claudio; Grabalosa Gándara, Marc; Graciani Diaz, Ricardo; Granado Cardoso, Luis Alberto; Graugés, Eugeni; Graverini, Elena; Graziani, Giacomo; Grecu, Alexandru; Greening, Edward; Gregson, Sam; Griffith, Peter; Grillo, Lucia; Grünberg, Oliver; Gui, Bin; Gushchin, Evgeny; Guz, Yury; Gys, Thierry; Hadavizadeh, Thomas; Hadjivasiliou, Christos; Haefeli, Guido; Haen, Christophe; Haines, Susan; Hall, Samuel; Hamilton, Brian; Han, Xiaoxue; Hansmann-Menzemer, Stephanie; Harnew, Neville; Harnew, Samuel; Harrison, Jonathan; He, Jibo; Head, Timothy; Heijne, Veerle; Hennessy, Karol; Henrard, Pierre; Henry, Louis; van Herwijnen, Eric; Heß, Miriam; Hicheur, Adlène; Hill, Donal; Hoballah, Mostafa; Hombach, Christoph; Hulsbergen, Wouter; Humair, Thibaud; Hussain, Nazim; Hutchcroft, David; Hynds, Daniel; Idzik, Marek; Ilten, Philip; Jacobsson, Richard; Jaeger, Andreas; Jalocha, Pawel; Jans, Eddy; Jawahery, Abolhassan; John, Malcolm; Johnson, Daniel; Jones, Christopher; Joram, Christian; Jost, Beat; Jurik, Nathan; Kandybei, Sergii; Kanso, Walaa; Karacson, Matthias; Karbach, Moritz; Karodia, Sarah; Kecke, Matthieu; Kelsey, Matthew; Kenyon, Ian; Kenzie, Matthew; Ketel, Tjeerd; Khairullin, Egor; Khanji, Basem; Khurewathanakul, Chitsanu; Klaver, Suzanne; Klimaszewski, Konrad; Kochebina, Olga; Kolpin, Michael; Komarov, Ilya; Koopman, Rose; Koppenburg, Patrick; Kozeiha, Mohamad; Kravchuk, Leonid; Kreplin, Katharina; Kreps, Michal; Krocker, Georg; Krokovny, Pavel; Kruse, Florian; Krzemien, Wojciech; Kucewicz, Wojciech; Kucharczyk, Marcin; Kudryavtsev, Vasily; Kuonen, Axel Kevin; Kurek, Krzysztof; Kvaratskheliya, Tengiz; Lacarrere, Daniel; Lafferty, George; Lai, Adriano; Lambert, Dean; Lanfranchi, Gaia; Langenbruch, Christoph; Langhans, Benedikt; Latham, Thomas; Lazzeroni, Cristina; Le Gac, Renaud; van Leerdam, Jeroen; Lees, Jean-Pierre; Lefèvre, Regis; Leflat, Alexander; Lefrançois, Jacques; Lemos Cid, Edgar; Leroy, Olivier; Lesiak, Tadeusz; Leverington, Blake; Li, Yiming; Likhomanenko, Tatiana; Liles, Myfanwy; Lindner, Rolf; Linn, Christian; Lionetto, Federica; Liu, Bo; Liu, Xuesong; Loh, David; Longstaff, Iain; Lopes, Jose; Lucchesi, Donatella; Lucio Martinez, Miriam; Luo, Haofei; Lupato, Anna; Luppi, Eleonora; Lupton, Oliver; Lusiani, Alberto; Machefert, Frederic; Maciuc, Florin; Maev, Oleg; Maguire, Kevin; Malde, Sneha; Malinin, Alexander; Manca, Giulia; Mancinelli, Giampiero; Manning, Peter Michael; Mapelli, Alessandro; Maratas, Jan; Marchand, Jean François; Marconi, Umberto; Marin Benito, Carla; Marino, Pietro; Marks, Jörg; Martellotti, Giuseppe; Martin, Morgan; Martinelli, Maurizio; Martinez Santos, Diego; Martinez Vidal, Fernando; Martins Tostes, Danielle; Massafferri, André; Matev, Rosen; Mathad, Abhijit; Mathe, Zoltan; Matteuzzi, Clara; Mauri, Andrea; Maurin, Brice; Mazurov, Alexander; McCann, Michael; McCarthy, James; McNab, Andrew; McNulty, Ronan; Meadows, Brian; Meier, Frank; Meissner, Marco; Melnychuk, Dmytro; Merk, Marcel; Michielin, Emanuele; Milanes, Diego Alejandro; Minard, Marie-Noelle; Mitzel, Dominik Stefan; Molina Rodriguez, Josue; Monroy, Ignacio Alberto; Monteil, Stephane; Morandin, Mauro; Morawski, Piotr; Mordà, Alessandro; Morello, Michael Joseph; Moron, Jakub; Morris, Adam Benjamin; Mountain, Raymond; Muheim, Franz; Müller, Dominik; Müller, Janine; Müller, Katharina; Müller, Vanessa; Mussini, Manuel; Muster, Bastien; Naik, Paras; Nakada, Tatsuya; Nandakumar, Raja; Nandi, Anita; Nasteva, Irina; Needham, Matthew; Neri, Nicola; Neubert, Sebastian; Neufeld, Niko; Neuner, Max; Nguyen, Anh Duc; Nguyen, Thi-Dung; Nguyen-Mau, Chung; Niess, Valentin; Niet, Ramon; Nikitin, Nikolay; Nikodem, Thomas; Novoselov, Alexey; O'Hanlon, Daniel Patrick; Oblakowska-Mucha, Agnieszka; Obraztsov, Vladimir; Ogilvy, Stephen; Okhrimenko, Oleksandr; Oldeman, Rudolf; Onderwater, Gerco; Osorio Rodrigues, Bruno; Otalora Goicochea, Juan Martin; Otto, Adam; Owen, Patrick; Oyanguren, Maria Aranzazu; Palano, Antimo; Palombo, Fernando; Palutan, Matteo; Panman, Jacob; Papanestis, Antonios; Pappagallo, Marco; Pappalardo, Luciano; Pappenheimer, Cheryl; Parker, William; Parkes, Christopher; Passaleva, Giovanni; Patel, Girish; Patel, Mitesh; Patrignani, Claudia; Pearce, Alex; Pellegrino, Antonio; Penso, Gianni; Pepe Altarelli, Monica; Perazzini, Stefano; Perret, Pascal; Pescatore, Luca; Petridis, Konstantinos; Petrolini, Alessandro; Petruzzo, Marco; Picatoste Olloqui, Eduardo; Pietrzyk, Boleslaw; Pilař, Tomas; Pinci, Davide; Pistone, Alessandro; Piucci, Alessio; Playfer, Stephen; Plo Casasus, Maximo; Poikela, Tuomas; Polci, Francesco; Poluektov, Anton; Polyakov, Ivan; Polycarpo, Erica; Popov, Alexander; Popov, Dmitry; Popovici, Bogdan; Potterat, Cédric; Price, Eugenia; Price, Joseph David; Prisciandaro, Jessica; Pritchard, Adrian; Prouve, Claire; Pugatch, Valery; Puig Navarro, Albert; Punzi, Giovanni; Qian, Wenbin; Quagliani, Renato; Rachwal, Bartolomiej; Rademacker, Jonas; Rama, Matteo; Ramos Pernas, Miguel; Rangel, Murilo; Raniuk, Iurii; Rauschmayr, Nathalie; Raven, Gerhard; Redi, Federico; Reichert, Stefanie; Reid, Matthew; dos Reis, Alberto; Ricciardi, Stefania; Richards, Sophie; Rihl, Mariana; Rinnert, Kurt; Rives Molina, Vincente; Robbe, Patrick; Rodrigues, Ana Barbara; Rodrigues, Eduardo; Rodriguez Lopez, Jairo Alexis; Rodriguez Perez, Pablo; Roiser, Stefan; Romanovsky, Vladimir; Romero Vidal, Antonio; Ronayne, John William; Rotondo, Marcello; Ruf, Thomas; Ruiz Valls, Pablo; Saborido Silva, Juan Jose; Sagidova, Naylya; Sail, Paul; Saitta, Biagio; Salustino Guimaraes, Valdir; Sanchez Mayordomo, Carlos; Sanmartin Sedes, Brais; Santacesaria, Roberta; Santamarina Rios, Cibran; Santimaria, Marco; Santovetti, Emanuele; Sarti, Alessio; Satriano, Celestina; Satta, Alessia; Saunders, Daniel Martin; Savrina, Darya; Schiller, Manuel; Schindler, Heinrich; Schlupp, Maximilian; Schmelling, Michael; Schmelzer, Timon; Schmidt, Burkhard; Schneider, Olivier; Schopper, Andreas; Schubiger, Maxime; Schune, Marie Helene; Schwemmer, Rainer; Sciascia, Barbara; Sciubba, Adalberto; Semennikov, Alexander; Serra, Nicola; Serrano, Justine; Sestini, Lorenzo; Seyfert, Paul; Shapkin, Mikhail; Shapoval, Illya; Shcheglov, Yury; Shears, Tara; Shekhtman, Lev; Shevchenko, Vladimir; Shires, Alexander; Siddi, Benedetto Gianluca; Silva Coutinho, Rafael; Silva de Oliveira, Luiz Gustavo; Simi, Gabriele; Sirendi, Marek; Skidmore, Nicola; Skwarnicki, Tomasz; Smith, Edmund; Smith, Eluned; Smith, Iwan Thomas; Smith, Jackson; Smith, Mark; Snoek, Hella; Sokoloff, Michael; Soler, Paul; Soomro, Fatima; Souza, Daniel; Souza De Paula, Bruno; Spaan, Bernhard; Spradlin, Patrick; Sridharan, Srikanth; Stagni, Federico; Stahl, Marian; Stahl, Sascha; Stefkova, Slavorima; Steinkamp, Olaf; Stenyakin, Oleg; Stevenson, Scott; Stoica, Sabin; Stone, Sheldon; Storaci, Barbara; Stracka, Simone; Straticiuc, Mihai; Straumann, Ulrich; Sun, Liang; Sutcliffe, William; Swientek, Krzysztof; Swientek, Stefan; Syropoulos, Vasileios; Szczekowski, Marek; Szumlak, Tomasz; T'Jampens, Stephane; Tayduganov, Andrey; Tekampe, Tobias; Teklishyn, Maksym; Tellarini, Giulia; Teubert, Frederic; Thomas, Christopher; Thomas, Eric; van Tilburg, Jeroen; Tisserand, Vincent; Tobin, Mark; Todd, Jacob; Tolk, Siim; Tomassetti, Luca; Tonelli, Diego; Topp-Joergensen, Stig; Torr, Nicholas; Tournefier, Edwige; Tourneur, Stephane; Trabelsi, Karim; Tran, Minh Tâm; Tresch, Marco; Trisovic, Ana; Tsaregorodtsev, Andrei; Tsopelas, Panagiotis; Tuning, Niels; Ukleja, Artur; Ustyuzhanin, Andrey; Uwer, Ulrich; Vacca, Claudia; Vagnoni, Vincenzo; Valenti, Giovanni; Vallier, Alexis; Vazquez Gomez, Ricardo; Vazquez Regueiro, Pablo; Vázquez Sierra, Carlos; Vecchi, Stefania; Velthuis, Jaap; Veltri, Michele; Veneziano, Giovanni; Vesterinen, Mika; Viaud, Benoit; Vieira, Daniel; Vieites Diaz, Maria; Vilasis-Cardona, Xavier; Volkov, Vladimir; Vollhardt, Achim; Volyanskyy, Dmytro; Voong, David; Vorobyev, Alexey; Vorobyev, Vitaly; Voß, Christian; de Vries, Jacco; Waldi, Roland; Wallace, Charlotte; Wallace, Ronan; Walsh, John; Wandernoth, Sebastian; Wang, Jianchun; Ward, David; Watson, Nigel; Websdale, David; Weiden, Andreas; Whitehead, Mark; Wilkinson, Guy; Wilkinson, Michael; Williams, Mark Richard James; Williams, Matthew; Williams, Mike; Williams, Timothy; Wilson, Fergus; Wimberley, Jack; Wishahi, Julian; Wislicki, Wojciech; Witek, Mariusz; Wormser, Guy; Wotton, Stephen; Wright, Simon; Wyllie, Kenneth; Xie, Yuehong; Xu, Zhirui; Yang, Zhenwei; Yu, Jiesheng; Yuan, Xuhao; Yushchenko, Oleg; Zangoli, Maria; Zavertyaev, Mikhail; Zhang, Liming; Zhang, Yanxi; Zhelezov, Alexey; Zhokhov, Anatoly; Zhong, Liang; Zucchelli, Stefano
2016-07-11
Associated production of bottomonia and open charm hadrons in $pp$ collisions at $\\sqrt{s}=7$ and $8$TeV is observed using data corresponding to an integrated luminosity of 3$fb^{-1}$ accumulated with the LHCb detector. The observation of five combinations, $\\Upsilon(1S)D^0$, $\\Upsilon(2S)D^0$, $\\Upsilon(1S)D^+$, $\\Upsilon(2S)D^+$ and $\\Upsilon(1S)D^+_{s}$, is reported. Production cross-sections are measured for $\\Upsilon(1S)D^0$ and $\\Upsilon(1S)D^+$ pairs in the forward region. The measured cross-sections and the differential distributions indicate the dominance of double parton scattering as the main production mechanism. This allows a precise measurement of the effective cross-section for double parton scattering.
High energy hadron-hadron collisions
International Nuclear Information System (INIS)
Chou, T.T.
1990-01-01
Results of a study on high energy collision with the geometrical model are summarized in three parts: (i) the elastic hadron-hadron collision, (ii) the inelastic hadron-hadron collision, and (iii) the e + e - annihilation. The geometrical description of high-energy elastic scattering developed earlier is still in general agreement with experiments at the CERN-S bar ppS energies. A simple one-parameter expression for the blackness of bar pp system has been proposed recently which describes very well all existing data from ISR to S bar ppS energies. The geometrical description has also been extended to include processes of fragmentation and diffraction dissociation and other phenomena. In the past five years, a unified physical picture for multiparticle emission in hadron-hadron and e + e - collisions was developed. It focuses on the idea of the wide range of values for the total angular momentum in hadron-hadron collisions. An extension of this consideration yields a theory for the momentum distribution of the outgoing particles which agrees with bar pp and e + e - collision experiments. The results and conclusions of this theory have been extrapolated to higher energies and yielded many predictions which can be experimentally tested. 37 refs
International Nuclear Information System (INIS)
Fagundes, Daniel Almeida
2010-01-01
The theoretical description of high-energy elastic hadron scattering constitutes an open problem in both, the underlying quantum field theory of strong interactions (QCD) and the phenomenological context. In this work the inverse problem in elastic hadron scattering is discussed in the impact parameter and eikonal frameworks, specifically a study on the empirical extraction of the profile, the inelastic overlap and the eikonal functions, from the experimental data and some principles and high-energy theorems (model independent). The analysis is limited to elastic proton-proton scattering in the center of momentum energy interval 19.4 - 62.5 GeV. In particular, a novel representation for the Martin's Real Part Formula is introduced but without the scaling property and suitable for empirical analysis. By means of this representation, and two other parametrizations previously introduced (constrained and unconstrained), several properties of the inelastic overlap function and the imaginary part of the eikonal (opacity) in the momentum transfer space are determined, in special: (1) evidence of a peripheral effect (tail) in the inelastic overlap function in the parameter impact space above 2 fm; (2) development of analytical parametrizations for this function leading to three gaussian components with centers at 0.0, ∼0.7 and ∼1.3 fm; (3) evidence of a finite zero (change of sign) in the opacity function in the momentum transfer space; (4) development of empirical parametrization for this function consistent with form factors as a product of two monopoles with constrained masses (not a dipole type) and a term with zero; (5) detailed discussion on the determination of the opacity function in the momentum transfer space through the semi-analytical approach. The applicability of these empirical results in the development of eikonal models (mainly those inspired in QCD) is also discussed. (author)
Adolph, C; Alexakhin, V Yu; Alexandrov, Yu; Alexeev, G D; Amoroso, A; Antonov, A A; Austregesilo, A; Badelek, B; Balestra, F; Barth, J; Baum, G; Bedfer, Y; Bernhard, J; Bertini, R; Bettinelli, M; Bicker, K; Bieling, J; Birsa, R; Bisplinghoff, J; Bordalo, P; Bradamante, F; Braun, C; Bravar, A; Bressan, A; Burtin, E; Chiosso, M; Chung, S U; Cicuttin, A; Crespo, M L; Dalla Torre, S; Das, S; Dasgupta, S S; Dasgupta, S; Denisov, O Yu; Dhara, L; Donskov, S V; Doshita, N; Duic, V; Dünnweber, W; Dziewiecki, M; Efremov, A; Elia, C; Eversheim, P D; Eyrich, W; Faessler, M; Ferrero, A; Filin, A; Finger, M; Finger, M; Fischer, H; Franco, C; du Fresne von Hoheneschedu, N; Friedrich, J M; Frolov, V; Garfagnini, R; Gautheron, F; Gavrichtchouk, O P; Gerassimov, S; Geyer, R; Giorgi, M; Gnesi, I; Gobbo, B; Goertz, S; Grabmüller, S; Grasso, A; Grube, B; Gushterski, R; Guskov, A; Guthörl, T; Haas, F; von Harrach, D; Heinsius, F H; Herrmann, F; Hess, C; Hinterberger, F; Horikawa, N; Höppner, Ch; d'Hose, N; Ishimoto, S; Ivanov, O; Ivanshin, Yu; Iwata, T; Jahn, R; Jary, V; Jasinski, P; Joosten, R; Kabuss, E; Kang, D; Ketzer, B; Khaustov, G V; Khokhlov, Yu A; Kisselev, Yu; Klein, F; Klimaszewski, K; Koblitz, S; Koivuniemi, J H; Kolosov, V N; Kondo, K; Königsmann, K; Konorov, I; Konstantinov, V F; Korzenev, A; Kotzinian, A M; Kouznetsov, O; Krämer, M; Kroumchtein, Z V; Kuhn, R; Kunne, F; Kurek, K; Lauser, L; Lednev, A A; Lehmann, A; Levorato, S; Lichtenstadt, J; Liska, T; Maggiora, A; Magnon, A; Makke, N; Mallot, G K; Mann, A; Marchand, C; Martin, A; Marzec, J; Matsuda, T; Meshcheryakov, G; Meyer, W; Michigami, T; Mikhailov, Yu V; Moinester, M A; Morreale, A; Mutter, A; Nagaytsev, A; Nagel, T; Negrini, T; Nerling, F; Neubert, S; Neyret, D; Nikolaenko, V I; Nowak, W -D; Nunes, A S; Olshevsky, A G; Ostrick, M; Padee, A; Panknin, R; Panzieri, D; Parsamyan, B; Paul, S; Perevalova, E; Pesaro, G; Peshekhonov, D V; Piragino, G; Platchkov, S; Pochodzalla, J; Polak, J; Polyakov, V A; Pretz, J; Quaresma, M; Quintans, C; Rajotte, J -F; Ramos, S; Rapatsky, V; Reicherz, G; Richter, A; Rocco, E; Rondio, E; Rossiyskaya, N S; Ryabchikov, D I; Samoylenko, V D; Sandacz, A; Sapozhnikov, M G; Sarkar, S; Savin, I A; Sbrizzai, G; Schiavon, P; Schill, C; Schlüter, T; Schmidt, K; Schmitt, L; Schönning, K; Schopferer, S; Schott, M; Schröder, W; Shevchenko, O Yu; Silva, L; Sinha, L; Sissakian, A N; Slunecka, M; Smirnov, G I; Sosio, S; Sozzi, F; Srnka, A; Steiger, L; Stolarski, M; Sulc, M; Sulej, R; Sznajder, P; Takekawa, S; Ter Wolbeek, J; Tessaro, S; Tessarotto, F; Tkatchev, L G; Uhl, S; Uman, I; Vandenbroucke, M; Virius, M; Vlassov, N V; Wang, L; Windmolders, R; Wislicki, W; Wollny, H; Zaremba, K; Zavertyaev, M; Zemlyanichkina, E; Ziembicki, M; Zhuravlev, N; Zvyagin, A
2013-01-01
The cross section for production of charged hadrons with high transverse momenta in scattering of 160 GeV/c muons off nucleons at low photon virtualities has been measured at the COMPASS experiment at CERN. The results, which cover transverse momenta from 1.1 to 3.6 GeV/c, are compared to a next-to-leading order perturbative Quantum Chromodynamics (NLO pQCD) calculation in order to evaluate the applicability of pQCD to this process in the kinematic domain of the experiment. The shape of the calculated differential cross section as a function of transverse momentum is found to be in good agreement with the experimental data, but the normalization is underestimated by NLO pQCD. This discrepancy may point towards the relevance of terms beyond NLO in the pQCD framework. The dependence of the cross section on the pseudo-rapidity and on the charge of the hadrons is also discussed.
Hadronization in nuclear matter
International Nuclear Information System (INIS)
Anton, G.; Blok, H.P.; Boudard, A.; Kopeliovich, B.
1993-01-01
The investigation of the space time structure of quark propagation and hadronization is proposed by studying particle production in deep-inelastic scattering of electrons from nucleons and nuclei with high statistics. A 15 to 30 GeV electron beam impinging on targets of hydrogen, deuterium, helium, carbon and lead is planned to be used and the final state hadrons are to be detected in a large solid angle device. (authors). 48 refs., 13 figs., 4 tabs
International Nuclear Information System (INIS)
Month, M.; Weng, W.T.
1983-01-01
The objective is to investigate whether existing technology might be extrapolated to provide the conceptual framework for a major hadron-hadron collider facility for high energy physics experimentation for the remainder of this century. One contribution to this large effort is to formalize the methods and mathematical tools necessary. In this report, the main purpose is to introduce the student to basic design procedures. From these follow the fundamental characteristics of the facility: its performance capability, its size, and the nature and operating requirements on the accelerator components, and with this knowledge, we can determine the technology and resources needed to build the new facility
The production of hadrons in the muon scattering on deuterium and xenon nuclei at 480 GeV
International Nuclear Information System (INIS)
Soeldner-Rembold, S.
1992-10-01
For the present thesis the hadronic final states of 6309 muon-deuterium events and 2064 muon-xenon events in the kinematical range Q 2 >1 (GeV/c) 2 , x>0.002, 0.1 3.5 mrad were studied. The multiplicity distributions of the muon-deuterium events and the muon-xenon events were described by means of the negative binomial distribution in intervals of the c.m. energy W. The two parameters anti n (mean multiplicity) and 1/k show for the muon-deuterium events a linear dependence on ln W 2 . The mean multiplicity anti n on xenon (anti n=10.43±0.19) is distinctly higher than on deuterium (anti n=7.76±0.07). The rapidity distributions of the positively charged and the negatively charged hadrons from muon-deuterium events are very well described by the Monte-Carlo program LUND. In the two-particle rapidity correlation both short-range and long-range correlations can be detected. The two-particle rapidity correlation in the xenon data are different from the deuterium data in the backward range. This difference indicates that the intranuclear cascade takes place in a limited range of small rapidities - relatively independently on the residual fragmentation process. (orig.) [de
Leading-order hadronic contribution to the electron and muon g-2
International Nuclear Information System (INIS)
Jegerlehner, Fred; Humboldt-Univ. Berlin
2015-11-01
I present a new data driven update of the hadronic vacuum polarization effects for the muon and the electron g-2. For the leading order contributions I find a had(1) μ =(686.99±4.21)[687.19±3.48] x 10 -10 based on e + e - data [incl. τ data], a had(2) μ =(-9.934± 0.091) x 10 -10 (NLO) and a had(3) μ =(1.226±0.012) x 10 -10 (NNLO) for the muon, and a had(1) e =(184.64±1.21) x 10 -14 (LO), a had(2) e =(-22.10±0.14) x 10 -14 (NLO) and a had(3) e =(2.79±0.02) x 10 -14 (NNLO) for the electron. A problem with vacuum polarization undressing of cross-sections (time-like region) is addressed. I also add a comment on properly including axial mesons in the hadronic light-by-light scattering contribution. My estimate here reads aμ[a 1 ,f 1 ' ,f 1 ]∝(7.51±2.71) x 10 -11 . With these updates a exp μ - the μ =(32.73±8.15) x 10 -10 a 4.0σ deviation, while a exp e -a the e =(-1.10±0.82) x 10 -12 shows no significant deviation.
What Can We Learn from Hadronic and Radiative Decays of Light Mesons?
Kubis, Bastian
2013-04-01
Chiral perturbation theory offers a powerful tool for the investigation of light pseudoscalar mesons. It incorporates the fundamental symmetries of QCD, interrelates various processes, and allows to link these to the light quark masses. Its shortcomings lie in a limited energy range: the radius of convergence of the chiral expansion is confined to below resonance scales. Furthermore, the strongest consequences of chiral symmetry are manifest for pseudoscalars (pions, kaons, eta) only: vector mesons, e.g., have a severe impact in particular for reactions involving photons. In this talk, I advocate dispersions relations as another model-independent tool to extend the applicability range of chiral perturbation theory. They even allow to tackle the physics of vector mesons in a rigorous way. It will be shown how dispersive methods can be used to resum large rescattering effects, and to provide model-independent links between hadronic and radiative decay modes. Examples to be discussed will include decays of the eta meson, giving access to light-quark-mass ratios or allowing to test the chiral anomaly; and meson transition form factors, which have an important impact on the hadronic light-by-light-scattering contribution to the anomalous magnetic moment of the muon.
Directory of Open Access Journals (Sweden)
Andreas van Hameren
2018-01-01
Full Text Available We discuss production of two μ+μ− pairs in ultraperipheral ultrarelativistic heavy ion collisions at the LHC. We take into account electromagnetic (two-photon double-scattering production and for a first time direct γγ production of four muons in one scattering. We study the unexplored process γγ→μ+μ−μ+μ−. We present predictions for total and differential cross sections. Measurable nuclear cross sections are obtained and corresponding differential distributions and counting rates are presented.
International Nuclear Information System (INIS)
Ashman, J.; Combley, F.; Salmon, D.; Whalley, M.; Wheeler, S.; Baum, G.; Caputo, M.C.; Hughes, V.W.; Oppenheim, R.F.; Papavassiliou, V.; Piegaia, R.; Schueler, K.P.; Bee, C.P.; Brown, S.C.; Court, G.; Francis, D.; Gabathuler, E.; Gamet, R.; Hayman, P.; Holt, J.R.; Jones, T.; Matthews, M.; Wimpenny, S.J.; Cheung, H.W.K.; Gibson, V.; Gillies, J.; Loken, J.; Renton, P.; Taylor, G.N.; Williams, W.S.C.; Womersley, J.; Coignet, G.; Favier, J.; Nagy, E.; Toth, J.; Urban, L.; Drees, J.; Edwards, A.W.; Hamacher, K.; Korzen, B.; Kruener, U.; Lauterjung, D.; Moenig, K.; Pavel, N.; Peschel, H.; Pietrzyk, U.; Schneider, A.; Wahlen, H.; Dycew, N.; Sloan, T.; Ernst, T.; Landgraf, U.; Schlagboehmer, A.; Schroeder, T.; Stier, H.E.; Stock, J.; Wallucks, W.; Ferrero, M.I.; Peroni, C.; Stajano, A.; Grafstroem, P.; Kullander, S.; Lettenstroem, F.; Lindqvist, T.; Lanske, D.; Schultze, K.; Urban, L.; Ziemons, K.; Windmolders, R.
1991-01-01
Final data measured with the EMC forward spectrometer are presented on the production of forward charged hardons in μp and μd scattering at incident beam energies between 100 and 280 GeV. The large statistics of 373 000 events allows a study of the semi-inclusive hadron production as a function of z, p T 2 and T 2 > in small Q 2 , x Bj and W bins. Charge multiplicity ratios and differences as a function of z and x Bj are given for p, d and n-targets. From the differences of charge multiplicities the ratio of the valence quark distributions of the proton d v (x)/u v (x) is determined for the first time in charged lepton scattering. The Gronau et al. sum rule is tested, the measured sum being 0.31±0.06 stat.±0.05 syst., compared with the theoretical expectation of 2/7≅0.286. The measured sum corresponds to an absolute value of the ratio of the d and u quark charge of 0.44±0.10 stat.±0.08 syst. (orig.)
International Nuclear Information System (INIS)
Billoir, P.
1983-02-01
Large angle two-body hadronic scattering was studied between 3 and 12 GeV/c by the WA 13 experiment at C.E.R.N. (Omega Spectrometer), with a negative RF separated beam, on a hydrogen target. The cross sections of these reactions, at fixed c.m. angle, decrease very rapidly with the energy; then high beam intensities were required together with high selectivity, obtained thanks to a multilevel triggering system, including a coplanarity chamber associated to a fast logic. This thesis describes the reactions with two charged final particles (π - p, K - p, antipp elastic scattering and antipp annihilation into two mesons). The kinematical reconstruction eliminates the background almost completely. More over a special vertex fitting method improves the reconstruction of the tracks, using their convergence at the same point to increase the geometrical information. Neglecting fixed t structures, the differential cross sections are compatible with the dimensional counting laws (however elastic antipp seems to decrease less rapidly than expected). Different models are compared with the results: no one agrees with the whole set of available data. This work emphasizes the handling of error matrices and the use of optimal estimation. It proposes a recursive track fitting method, optimized with respect to the multiple scattering [fr
Quantum chromodynamics and hadron jets
International Nuclear Information System (INIS)
Dokshitser, Y.L.; Dyakonov, D.I.
1979-07-01
These lectures are devoted to the description of the various properties of hard scattering processes with the participation of hadrons in the framework of Quantum Chromodynamics. We discuss in detail the validity and region of applicability of perturbation theory applied to hadron processes. Particular attention is paid to the question of the structure of quark and gluon jets produced in hard processes (as an example, e + e - annihilation into hadrons). In addition to giving a pedagogical review, we also present new results. (orig.)
Czech Academy of Sciences Publication Activity Database
Adolph, C.; Aghasyan, M.; Akhunzyanov, R.; Alexeev, G. D.; Alexeev, M.; Amoroso, A.; Andrieux, V.; Anfimov, N. V.; Anosov, V.; Augsten, K.; Augustyniak, W.; Austregesilo, A.; Azevedo, C.; Badelek, B.; Balestra, F.; Barth, J.; Beck, D.; Bedfer, Y.; Bernhard, J.; Bicker, K.; Bielert, E. R.; Birsa, R.; Bisplinghoff, J.; Bodlák, M.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bressan, A.; Büchele, M.; Capozza, L.; Chang, W.-C.; Chatterjee, C.; Chiosso, M.; Choi, I.; Chung, S.U.; Cicuttin, A.; Crespo, M.; Curiel, Q.; Dalla Torre, S.; Dasgupta, S. S.; Dasgupta, S.; Denisov, O.; Dhara, L.; Donskov, S. V.; Doshita, N.; Duic, V.; Dünnweber, W.; Dziewiecki, M.; Efremov, A.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Finger, M.; Finger jr., M.; Fischer, H.; Franco, C.; Fresne von Hohenesche, N.; Friedrich, J. M.; Frolov, V.; Fuchey, E.; Gautheron, F.; Gavrichtchouk, O. P.; Gerassimov, S.; Giordano, F.; Gnesi, I.; Gorzellik, M.; Grabmüller, S.; Grasso, A.; Grosse-Perdekapm, M.; Grube, B.; Grussenmeyer, T.; Guskov, A.; Haas, F.; Hahne, D.; von Harrach, D.; Hashimoto, R.; Heinsius, F. H.; Heitz, R.; Herrmann, E.; Hinterberger, F.; Horikawa, N.; d'Hose, N.; Hsieh, C.-Yu.; Huber, S.; Ishimoto, S.; Ivanov, A.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jarý, V.; Joosten, R.; Jörg, P.; Kabuss, E.; Ketzer, B.; Khaustov, G. V.; Khokhlov, Yu. A.; Kisselev, Y.; Klein, F.; Klimaszewski, K.; Koivuniemi, J. H.; Kolosov, V. N.; Kondo, K.; Königsmann, K.; Konorov, I.; Konstantinov, V. F.; Kotzinian, A. M.; Kouznetsov, O.; Krämer, M.; Kremser, P.; Krinner, F.; Kroumchtein, Z. V.; Kuhn, R.; Kulinich, Y.; Kunne, F.; Kurek, K.; Kurjata, R. P.; Lednev, A. A.; Lehmann, A.; Levillain, M.; Levorato, S.; Lian, Y.-S.; Lichtenstadt, J.; Longo, R.; Maggiora, A.; Magnon, A.; Makins, N.; Makke, N.; Mallot, G. K.; Marchand, C.; Marianski, B.; Martin, A.; Marzec, J.; Matoušek, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.; Meyer, M.; Meyer, W.; Michigami, T.; Mikhailov, Yu. V.; Mikhasenko, M.; Mitrofanov, E.; Mitrofanov, N.; Miyachi, Y.; Montuenga, P.; Nagaytsev, A.; Nerling, F.; Neyret, D.; Nikolaenko, V. I.; Nový, J.; Nowak, W. D.; Nukazuka, G.; Nunes, A.S.; Olshevsky, A. G.; Orlov, I.; Ostrick, M.; Panzieri, D.; Parsamyan, B.; Paul, S.; Peng, J.-C.; Pereira, F.; Pešek, M.; Peshekhonov, D. V.; Pierre, N.; Platchkov, S.; Pochodzalla, J.; Polyakov, V. A.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Regali, C.; Reicherz, G.; Riedl, C.; Roskot, M.; Rossiyskaya, N. S.; Ryabchikov, D.; Rybnikov, A.; Rychter, A.; Salač, R.; Samoylenko, V. D.; Sandacz, A.; Santos, C.; Sarkar, S.; Savin, I. A.; Sawada, T.; Sbrizzai, G.; Schiavon, P.; Schmidt, K.; Schmieden, H.; Schönning, K.; Schopferer, S.; Seder, E.; Selyunin, A.; Shevchenko, O. Yu.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Smolík, J.; Sozzi, F.; Srnka, Aleš; Steffen, D.; Stolarski, M.; Šulc, M.; Suzuki, H.; Szabelski, A.; Szameitat, T.; Sznajder, P.; Takekawa, S.; Tasevsky, M.; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Tosello, F.; Tskhay, V.; Uhl, S.; Veloso, J.; Virius, M.; Vondra, J.; Weisrock, T.; Wilfert, M.; Windmolders, R.; Ter Wolbeek, J.; Zaremba, K.; Závada, P.; Zavertyaev, M.; Zemlyanichkina, E.; Zhuravlev, N.; Ziembicki, M.; Zink, A.
2017-01-01
Roč. 764, JAN (2017), s. 1-10 ISSN 0370-2693 R&D Projects: GA MŠk(CZ) LO1212 Institutional support: RVO:68081731 Keywords : deep inelastic scattering * pion multiplicities * fragmentation functions Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Nuclear physics Impact factor: 4.807, year: 2016
Energy Technology Data Exchange (ETDEWEB)
Michael, Douglas Grant [Harvard U.
1990-01-01
The transverse momentum and energy-flow properties of forward ($x_F$ > 0) charged . hadrons and photons in deep inelastic muon scattering at 490GeV/c have been studied. Single particle transverse momentum and average transverse momentum as a function of $x_{Feynmen}$ are presented.Events are found to have a planar structure and transverse momentum spectra in and out of the event plane are presented. Data in the kinematic range $Q^2 > 3$ $GeV^2/c^2$ and 20 < W < 30 GeV/$c^2$ are used to search for two jets of particles in the forward direction. Energy and particle flow with.in the hadronic event plane are presented with several different cuts made on the data. A jet reconstruction algorithm is applied and properties of the forward jets are studied. For all plots, comparison is made with predictions from the Lund Monte Carlo tuned in different fashions. It is found that it is necessary to include hard QCD processes (gluon bremsstrahlung and photon-gluon fusion) in order to achieve good agreen1eut between the data and the Monte Carlo. In addition, it is shown that the data have more multi-jet events than predicted by the default version of the Lund ( 4.3) Monte Carlo.. It is suggested that it is necessary to increase the overall 'jettiness' by either increasing the primordial gluon distribution of the nucleon or adjusting the production cross section in the Monte Carlo. The possibility of an increased gluon distribution is presented and compared to data.
Hadron multiplicities at COMPASS
Energy Technology Data Exchange (ETDEWEB)
Du Fresne von Hohenesche, Nicolas [Institut fuer Kernphysik, Universitaet Mainz, Johann-Joachim-Becher-Weg 45, 55128 Mainz (Germany); Collaboration: COMPASS Collaboration
2014-07-01
Quark fragmentation functions (FF) D{sub q}{sup h}(z,Q{sup 2}) describe final-state hadronization of quarks q into hadrons h. The FFs can be extracted from hadron multiplicities produced in semi-inclusive deep inelastic scattering. The COMPASS collaboration has recently measured charged hadron multiplicities for identified pions and kaons using a 160 GeV/c muon beam impinging on an iso-scalar target. The data cover a large kinematical range and provide an important input for global QCD analyses of world data at NLO, aiming at the determination of FFs in particular in the strange quark sector. The newest results from COMPASS on pion and kaon multiplicities will be presented.
Energy Technology Data Exchange (ETDEWEB)
Gauron, P.; Nicolescu, B. [Paris-11 Univ., 91 - Orsay (France). Inst. de Physique Nucleaire; Selyugin, O.V. [Joint Inst. for Nuclear Research, Dubna (Russian Federation). Bogoliubov Lab. of Theoretical Physics
1996-10-01
It is shown that the high precision UA4/2 data for differential cross sections p-barp scattering are compatible with the presence of Auberson -Kinoshita - Martin (AKM) type of oscillations at very small momentum transfers. These oscillations seem to be periodic in {radical}|t|. The existence of such visible oscillations suggests a general mechanism of saturation of axiomatic bounds. As an illustration the consequences for extracting the parameter {rho} = ReF/ImF from dN/dt data are also discussed. (K.A.). 19 refs.
International Nuclear Information System (INIS)
Fischer, J.; Kolar, P.; Kundrat, V.
1988-01-01
The proceedings contain invited lectures and papers presente at the symposium. Attention was devoted to hadron interactions a high energy in QCD, to the structure and decay of hadrons, the production of hadrons and supersymmetric particles in e + e - and ep collisions, to perturbation theory in quantum field theory, and new supersymmetric extensions of relativistic algebra. (Z.J
Nuclei, hadrons, and elementary particles
International Nuclear Information System (INIS)
Bopp, F.W.
1989-01-01
This book is a short introduction to the physics of the nuclei, hadrons, and elementary particles for students of physics. Important facts and model imaginations on the structure, the decay, and the scattering of nuclei, the 'zoology' of the hadrons and basic facts of hadronic scattering processes, a short introduction to quantum electrodynamics and quantum chromodynamics and the most important processes of lepton and parton physics, as well as the current-current approach of weak interactions and the Glashow-Weinberg-Salam theory are presented. (orig.) With 153 figs., 10 tabs [de
International Nuclear Information System (INIS)
Quigg, C.
1982-11-01
The subject of hadron jet studies, to judge by the work presented at this workshop, is a maturing field which is still gathering steam. The very detailed work being done in lepton-lepton and lepton-hadron collisions, the second-generation measurements being carried out at Fermilab, the CERN SPS, and the ISR, and the very high energy hard scatterings being observed at the CERN Collider all show enormous promise for increased understanding. Perhaps we shall yet reach that long-sought nirvana in which high-p/sub perpendicular/ collisions become truly simple
Hadron excitation of giant resonances
International Nuclear Information System (INIS)
Morsch, H.-P.
1985-01-01
A review is given on giant resonance studies in heavy nuclei using scattering of different hadronic probes. Concerning isoscalar giant resonances compression modes are discussed with the possibility to obtain more detailed structure information. From detailed studies of α scattering the distribution of isoscalar strengths of multipolarity up to L=6 was obtained. Some recent aspects of heavy ion excitation of collective modes are mentioned. The possibility to study isovector giant resonances in hadron charge exchange reactions is discussed. Finally, a comparison is made between α and 200 MeV proton scattering from which isoscalar and spin-isospin continuum response are extracted. (orig.)
International Nuclear Information System (INIS)
Oka, Makoto
2012-01-01
Spectra of hadrons show various and complex structures due to the strong coupling constants of the quantum chromodynamics (QCD) constituting its fundamental theory. For their understandings, two parameters, i.e., (1) the quark mass and (2) their excitation energies are playing important roles. In low energies, for example, rather simple structures similar to the positronium appear in the heavy quarks such as charms and bottoms. It has been, however, strongly suggested by the recent experiments that the molecular resonant state shows up when the threshold to decay to mesons is exceeded. On the other hand, chiral symmetry and its breaking play important roles in the dynamics of light quarks. Strange quarks are in between and show special behaviors. In the present lecture, the fundamental concept of the hadron spectroscopy based on the QCD is expounded to illustrate the present understandings and problems of the hadron spectroscopy. Sections are composed of 1. Introduction, 2. Fundamental Concepts (hadrons, quarks and QCD), 3. Quark models and exotic hadrons, 4. Lattice QCD and QCD sum rules. For sections 1 to 3, only outline of the concepts is described because of the limited space. Exotic hadrons, many quark pictures of light hadrons and number of quarks in hadrons are described briefly. (S. Funahashi)
International Nuclear Information System (INIS)
Broome, J.
1965-11-01
The programme SCATTER is a KDF9 programme in the Egtran dialect of Fortran to generate normalized angular distributions for elastically scattered neutrons from data input as the coefficients of a Legendre polynomial series, or from differential cross-section data. Also, differential cross-section data may be analysed to produce Legendre polynomial coefficients. Output on cards punched in the format of the U.K. A. E. A. Nuclear Data Library is optional. (author)
Simulation of soft hadron hadron collisions at ultrarelativistic energies
International Nuclear Information System (INIS)
Werner, K.
1987-01-01
An event generator to simulate ultrarelativistic hadron hadron collisions is proposed. It is based on the following main assumptions: the process can be divided into two independent steps, string formation and string fragmentation; strings are formed as a consequence of color exchange between a quark of the projectile and a quark of the target; the fragmentation of strings is the same as in e + e - annihilation or in lepton nucleon scattering. 11 refs., 4 figs
Composite hadrons and relativistic nuclei
International Nuclear Information System (INIS)
Blankenbecler, R.
1978-01-01
Lectures are presented describing a model of hadronic scattering at large momentum transfer, either transverse or longitudinal. This model emphasizes in this regime the importance of forces involving the interchange of constituents of the hadrons, hence its name, the constituent interchange model CIM. The CIM is a rearrangement of standard perturbation theory to take into account the fact that the binding force is very strong in color singlet states (singlet dominance). The hard scattering expansion, incoherence problems, nuclear wave functions and counting rules, interaction between nuclei, pion and proton yields and form factors, structure functions and nonscaling, massive lepton pairs, hadrons at large transverse momentum, and quark-quark scattering are treated. 49 references
International Nuclear Information System (INIS)
Schneider, J.L.
1993-12-01
The hadronic final state in deep inelastic e - P collisions has been studied with the 1992 data from the ZEUS detector at HERA. The hadronic final state is described by event topology variables like thrust and sphericity and also by variables like multiplicity and transverse momentum. These quantities require the reconstruction of the particle four moments which are calculated from calorimeter cell clusters (condensates). A detailed Monte-Carlo comparison between final state particles and condensates is presented. ZEUS data and model predictions are compared in the γ * P system. Good agreement between data and models is found in the x-Feynman and transverse momentum spectra and in the seagull plot. Mean thrust and sphericity are measured as functions of the invariant mass W of the hadronic final state. They significantly deviate from the model predictions, as do the mean multiplicities, which exceed the model predictions by about 1 unit. (orig.)
HIGH ENERGY HADRON POLARIMETRY
International Nuclear Information System (INIS)
BUNCE, G.
2007-01-01
Proton polarimetry at RHIC uses the interference of electromagnetic (EM) and hadronic scattering amplitudes. The EM spin-flip amplitude for protons is responsible for the proton's anomalous magnetic moment, and is large. This then generates a significant analyzing power for small angle elastic scattering. RHIC polarimetry has reached a 5% uncertainty on the beam polarization, and seem capable of reducing this uncertainty further. Polarized neutron beams ax also interesting for RHIC and for a polarized electron-polarized proton/ion collider in the fume. In this case, deuterons, for example, have a very small anomalous magnetic moment, making the approach used for protons impractical. Although it might be possible to use quasielastic scattering from the protons in the deuteron to monitor the polarization. 3-He beams can provide polarized neutrons, and do have a large anomalous magnetic moment, making a similar approach to proton polarimetry possible
International Nuclear Information System (INIS)
Close, F.E.
1987-09-01
The standard theory of colour forces (Quantum Chromodynamics) suggests that in addition to the familiar hadrons made of quarks, there should exist new states where coloured gluons play an essential dynamical role. The author reviews the theoretical predictions for the properties of these ''glueballs'' and of states containing resonating quarks and gluons. Attempts are made to highlight those features which are common to several models in the literature. Experimental candidates are confronted with the models. No clear cut signal for a gluonic hadron yet exists; consequently what future data are required to determine the constituency of some popular candidates is considered. (author)
Hadron interactions in quark models
International Nuclear Information System (INIS)
Narodetskij, I.M.
1987-01-01
Some recent developments on the study of quark degrees of freedom in hadron scattering at intermediate energy are reviewed. Physical foundations of the P-matrix approach and the Quark Compound Bag method are discussed including applications to pion-pion, pion-nucleon, nucleon-nucleon and three-nucleon systems
International Nuclear Information System (INIS)
Dremin, I.M.
1981-01-01
The process of the coherent production of hadrons analogous to Cherenkov radiation of photons is considered. Its appearence and qualitative treatment are possible now because it is known from experiment that the real part of the πp (and pp) forward elastic scattering amplitude is positive at high energies. The threshold behaviour of the process as well as very typical angular and psub(T)-distributions where psub(t)-transverse momentum corresponding to the ring structure of the target diagram at rather large angles and to high-psub(T) jet production are emphasized [ru
Hadron muoproduction at the COMPASS experiment
Rajotte, J F
The COMPASS Collaboration has two main fields of interest: to improve our knowledge of the nucleon spin structure and to study hadrons through spectroscopy. These goals require a multipurpose universal spectrometer such as the COmmon Muon and Proton Apparatus for Structure and Spectroscopy, COMPASS. In its first years of data taking (2002-2007), the nucleon spin structure was studied with a polarized muon beam scattering off a polarized target. These studies resumed in 2010 and will continue until at least 2011. The years 2008 and 2009 were dedicated to hadron spectroscopy using hadron beams. In the case of the nucleon structure studies, it is crucial to detect with high precision the incoming beam muon (160 GeV), the scattered muon and the produced hadrons. The large amount of high quality data accumulated provides access to the unpolarized and polarized parton distributions of the nucleon and the hadronization process. Subtle differences (asymmetries) between polarized cross sections have been predicted for...
Parton-hadron cascade approach at SPS and RHIC
Energy Technology Data Exchange (ETDEWEB)
Nara, Yasushi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment
1998-07-01
A parton-hadron cascade model which is the extension of hadronic cascade model incorporating hard partonic scattering based on HIJING is presented to describe 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 HIJING and VNI. Baryon density, energy density and temperature for RHIC are calculated within this model. (author)
International Nuclear Information System (INIS)
Anon.
1986-01-01
The European Hadron Facility (EHF) is a project for particle and nuclear physics in the 1990s which would consist of a fast cycling high intensity proton synchrotron of about 30 GeV primary energy and providing a varied spectrum of intense high quality secondary beams (polarized protons, pions, muons, kaons, antiprotons, neutrinos). The physics case of this project has been studied over the last two years by a European group of particle and nuclear physicists (EHF Study Group), whilst the conceptual design for the accelerator complex was worked out (and is still being worked on) by an international group of machine experts (EHF Design Study Group). Both aspects have been discussed in recent years in a series of working parties, topical seminars, and workshops held in Freiburg, Trieste, Heidelberg, Karlsruhe, Les Rasses and Villigen. This long series of meetings culminated in the International Conference on a European Hadron Facility held in Mainz from 10-14 March
Geometrical scaling in high energy hadron collisions
International Nuclear Information System (INIS)
Kundrat, V.; Lokajicek, M.V.
1984-06-01
The concept of geometrical scaling for high energy elastic hadron scattering is analyzed and its basic equations are solved in a consistent way. It is shown that they are applicable to a rather small interval of momentum transfers, e.g. maximally for |t| 2 for pp scattering at the ISR energies. (author)
International Nuclear Information System (INIS)
Bunce, G.
1984-01-01
Is all hadronic physics ultimately describable by QCD. Certainly, many disparate phenomena can be understood within the QCD framework. Also certainly, there are important questions which are open, both theoretically (little guidance, as yet) and experimentally, regarding confinement. Are there dibaryons, baryonium, glueballs. In addition, there are experimental results which at present do not have an explanation. This talk, after a short section on QCD successes and difficulties, will emphasize two experimental topics which have recent results - glueball spectroscopy and exclusive reactions at large momentum transfer. Both are experimentally accessible in the AGS/LAMPF II/AGS II/TRIUMF II/SIN II energy domain
Energy Technology Data Exchange (ETDEWEB)
Gauron, P. [Theory Group, Laboratoire de Physique Nucleaire et des Hautes Energies (LPNHE), CNRS, and Universite Pierre et Marie Curie, Paris (France)]. E-mail: gauron@in2p3.fr; Nicolescu, B. [Theory Group, Laboratoire de Physique Nucleaire et des Hautes Energies (LPNHE), CNRS, and Universite Pierre et Marie Curie, Paris (France)]. E-mail: nicolesc@lpnhep.in2p3.fr; Selyugin, O.V. [BLTP, JINR, Dubna, Moscow region (Russian Federation)]. E-mail: selugin@thsun1.jinr.ru
2005-11-24
A new method for the determination of the real part of the elastic scattering amplitude is examined for high energy proton-proton at small momentum transfer. This method allows us to decrease the number of model assumptions, to obtain the real part in a narrow region of momentum transfer and to test different models. The real part is computed at a given point t{sub min} near t=0 from the known Coulomb amplitude. Hence one obtains an important constraint on the real part of the forward scattering amplitude and therefore on the {rho}-parameter (measuring the ratio of the real to imaginary part of the scattering amplitude at t=0), which can be tested at LHC.
De Wolf, E.A.
2002-01-01
We discuss basic concepts and properties of diffractive phenomena in soft hadron collisions and in deep-inelastic scattering at low Bjorken-x. The paper is not a review of the rapidly developing field but presents an attempt to show in simple terms the close inter-relationship between the dynamics of high-energy hadronic and deep-inelastic diffraction. Using the saturation model of Golec-Biernat and Wusthoff as an example, a simple explanation of geometrical scaling is presented. The relation between the QCD anomalous multiplicity dimension and the Pomeron intercept is discussed.
International Nuclear Information System (INIS)
Wolf, E.A. de
2002-01-01
We discuss basic concepts and properties of diffractive phenomena in soft hadron collisions and in deep-inelastic scattering at low Bjorken - x. The paper is not a review of the rapidly developing field but presents an attempt to show in simple terms the close inter-relationship between the dynamics of high-energy hadronic and deep-inelastic diffraction. Using the saturation model of Golec-Biernat and Wuesthoff as an example, a simple explanation of geometrical scaling is presented. The relation between the QCD anomalous multiplicity dimension and the Pomeron intercept is discussed. (author)
The Emergence of Hadrons from QCD Color
Brooks, William; Color Dynamics in Cold Matter (CDCM) Collaboration
2015-10-01
The formation of hadrons from energetic quarks, the dynamical enforcement of QCD confinement, is not well understood at a fundamental level. In Deep Inelastic Scattering, modifications of the distributions of identified hadrons emerging from nuclei of different sizes reveal a rich variety of spatial and temporal characteristics of the hadronization process, including its dependence on spin, flavor, energy, and hadron mass and structure. The EIC will feature a wide range of kinematics, allowing a complete investigation of medium-induced gluon bremsstrahlung by the propagating quarks, leading to partonic energy loss. This fundamental process, which is also at the heart of jet quenching in heavy ion collisions, can be studied for light and heavy quarks at the EIC through observables quantifying hadron ``attenuation'' for a variety of hadron species. Transverse momentum broadening of hadrons, which is sensitive to the nuclear gluonic field, will also be accessible, and can be used to test our understanding from pQCD of how this quantity evolves with pathlength, as well as its connection to partonic energy loss. The evolution of the forming hadrons in the medium will shed new light on the dynamical origins of the forces between hadrons, and thus ultimately on the nuclear force. Supported by the Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT) of Chile.
Deep inelastic lepton scattering
International Nuclear Information System (INIS)
Nachtmann, O.
1977-01-01
Deep inelastic electron (muon) nucleon and neutrino nucleon scattering as well as electron positron annihilation into hadrons are reviewed from a theoretical point of view. The emphasis is placed on comparisons of quantum chromodynamics with the data. (orig.) [de
Study of the hadronisation process from single hadron and hadron-pair production in SIDIS at COMPASS
Makke, Nour
2014-01-01
Hadron production in hard scattering reactions is described by the hadronization mechanism which combines quarks into final-state hadrons. Within the theoretical framework of leading-twist collinear QCD, the cross section for hadron production in semi-inclusive deep-inelastic scattering can be factorized into a hard scattering cross section describing the hard interaction at the quark level calculable in perturbative QED, and non-perturbative universal functions: parton distribution functions which reflect the quark structure of initial-state hadrons and collinear fragmentation functions which encode details on the hadronization process. In the last decades, a major effort has been achieved on theoretical and experimental levels and allowed to constraint, with very high precision, parton distribution functions except strange quark distribution, which still carries large uncertainties. Fragmentation functions, however, remain at a very preliminary stage of study with a growing interest in a more accurate and p...
Interplay among transversity induced asymmetries in hadron leptoproduction
Adolph, C.; Alexeev, M.G.; Alexeev, G.D.; Amoroso, A.; Andrieux, V.; Anosov, V.; Augustyniak, W.; Austregesilo, A.; Azevedo, C.D.R.; Badelek, B.; Balestra, F.; Barth, J.; Beck, R.; Bedfer, Y.; Bernhard, J.; Bicker, K.; Bielert, E.R.; Birsa, R.; Bisplinghoff, J.; Bodlak, M.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bressan, A.; Buchele, M.; Burtin, E.; Chang, W.C.; Chiosso, M.; Choi, I.; Chung, S.U.; Cicuttin, A.; Crespo, M.L.; Curiel, Q.; d'Hose, N.; Dalla Torre, S.; Dasgupta, S.S.; Dasgupta, S.; Denisov, O.Yu.; Dhara, L.; Donskov, S.V.; Doshita, N.; Duic, V.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P.D.; Eyrich, W.; Ferrero, A.; Finger, M.; M. Finger jr; Fischer, H.; Franco, C.; von Hohenesche, N. du Fresne; Friedrich, J.M.; Frolov, V.; Fuchey, E.; Gautheron, F.; Gavrichtchouk, O.P.; Gerassimov, S.; Giordano, F.; Gnesi, I.; Gorzellik, M.; Grabmuller, S.; Grasso, A.; Grosse-Perdekamp, M.; Grube, B.; Grussenmeyer, T.; Guskov, A.; Haas, F.; Hahne, D.; von Harrach, D.; Hashimoto, R.; Heinsius, F.H.; Herrmann, F.; Hinterberger, F.; Horikawa, N.; Hsieh, C.Yu; Huber, S.; Ishimoto, S.; Ivanov, A.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jorg, P.; Joosten, R.; Kabuss, E.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu. A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koivuniemi, J.H.; Kolosov, V.N.; Kondo, K.; Konigsmann, K.; Konorov, I.; Konstantinov, V.F.; Kotzinian, A.M.; Kouznetsov, O.; Kramer, M.; Kremser, P.; Krinner, F.; Kroumchtein, Z.V.; Kuchinski, N.; Kunne, F.; Kurek, K.; Kurjata, R.P.; Lednev, A.A.; Lehmann, A.; Levillain, M.; Levorato, S.; Lichtenstadt, J.; Longo, R.; Maggiora, A.; Magnon, A.; Makins, N.; Makke, N.; Mallot, G.K.; Marchand, C.; Marianski, B.; Martin, A.; Marzec, J.; Matousek, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Yu. V.; Miyachi, Y.; Montuenga, P.; Nagaytsev, A.; Nerling, F.; Neyret, D.; Nikolaenko, V.I.; Novy, J.; Nowak, W.D.; Nukazuka, G.; Nunes, A.S.; Olshevsky, A.G.; Orlov, I.; Ostrick, M.; Panzieri, D.; Parsamyan, B.; Paul, S.; Peng, J.C.; Pereira, F.; Pesaro, G.; Pesek, M.; Peshekhonov, D.V.; Platchkov, S.; Pochodzalla, J.; Polyakov, V.A.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Regali, C.; Reicherz, G.; Riedl, C.; Rossiyskaya, N.S.; Ryabchikov, D.I.; Rychter, A.; Samoylenko, V.D.; Sandacz, A.; Santos, C.; Sarkar, S.; Savin, I.A.; Sbrizzai, G.; Schiavon, P.; Schmidt, K.; Schmieden, H.; Schonning, K.; Schopferer, S.; Selyunin, A.; Shevchenko, O.Yu.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Sozzi, F.; Srnka, A.; Stolarski, M.; Sulc, M.; Suzuki, H.; Szabelski, A.; Szameitat, T.; Sznajder, P.; Takekawa, S.; Wolbeek, J. ter; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Tosello, F.; Tskhay, V.; Uhl, S.; Veloso, J.; Virius, M.; Weisrock, T.; Wilfert, M.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zink, A.
2016-01-01
In the fragmentation of a transversely polarized quark several left-right asymmetries are possible for the hadrons in the jet. When only one unpolarized hadron is selected, it exhibits an azimuthal modulation known as Collins effect. When a pair of oppositely charged hadrons is observed, three asymmetries can be considered, a di-hadron asymmetry and two single hadron asymmetries. In lepton deep inelastic scattering on transversely polarized nucleons all these asymmetries are coupled with the transversity distribution. From the high statistics COMPASS data on oppositely charged hadron-pair production we have investigated for the first time the dependence of these three asymmetries on the difference of the azimuthal angles of the two hadrons. The similarity of transversity induced single and di-hadron asymmetries is discussed. A phenomenological analysis of the data allows to establish quantitative relationships among them, providing strong indication that the underlying fragmentation mechanisms are all driven ...
High energy hadron spin-flip amplitude
International Nuclear Information System (INIS)
Selyugin, O.V.
2016-01-01
The high-energy part of the hadron spin-flip amplitude is examined in the framework of the new high-energy general structure (HEGS) model of the elastic hadron scattering at high energies. The different forms of the hadron spin-flip amplitude are compared in the impact parameter representation. It is shown that the existing experimental data of the proton-proton and proton-antiproton elastic scattering at high energy in the region of the diffraction minimum and at large momentum transfer give support in the presence of the energy-independent part of the hadron spin-flip amplitude with the momentum dependence proposed in the works by Galynskii-Kuraev. [ru
Slope of differential cross sections and size of hadron spin-flip amplitude
International Nuclear Information System (INIS)
Selyugin, O.V.
1998-01-01
A possibility to obtain restrictions of the size of the elastic spin-flip hadron scattering amplitude from the exactly measured experimental data on the differential cross sections of elastic hadron-hadron scattering is shown and possible sizes are calculated. Appropriate estimations confirm the previous analysis of experimental data at √s = 540 GeV and a probable contribution of the hadron spin-flip amplitude
Summary: Hadron dynamics sessions
International Nuclear Information System (INIS)
Carroll, A.S.; Londergan, J.T.
1993-01-01
Four sessions on Hadron Dynamics were organized at this Workshop. The first topic, QCD Exclusive Reactions and Color Transparency, featured talks by Ralston, Heppelman and Strikman; the second, QCD and Inclusive Reactions had talks by Garvey, Speth and Kisslinger. The third dynamics session, Medium Modification of Elementary Interactions had contributions from Kopeliovich, Alves and Gyulassy; the fourth session Pre-QCD Dynamics and Scattering, had talks by Harris, Myhrer and Brown. An additional joint Spectroscopy/Dynamics session featured talks by Zumbro, Johnson and McClelland. These contributions are reviewed briefly in this summary. Two additional joint sessions between Dynamics and η physics are reviewed by the organizers of the Eta sessions. In such a brief review there is no way the authors can adequately summarize the details of the physics presented here. As a result, they concentrate only on brief impressionistic sketches of the physics topics discussed and their interrelations. They include no bibliography in this summary, but simply refer to the talks given in more detail in the Workshop proceedings. They focus on topics which were common to several presentations in these sessions. First, nuclear and particle descriptions of phenomena are now clearly converging, in both a qualitative and quantitative sense; they show several examples of this convergence. Second, an important issue in hadron dynamics is the extent to which elementary interactions are modified in nuclei at high energies and/or densities, and they illustrate some of these medium effects. Finally, they focus on those dynamical issues where hadron facilities can make an important, or even a unique, contribution to the knowledge of particle and nuclear physics
The theory of hadronic systems
International Nuclear Information System (INIS)
Gibbs, W.R.
1995-01-01
This report briefly discusses progress on the following topics: isospin breaking in the pion-nucleon system; subthreshold amplitudes in the πN system; neutron-proton charge-exchange; transparency in pion production; energy dependence of pion DCX; direct capture of pions into deeply bound atomic states; knock out of secondary components in the nucleus; radii of neutron distributions in nuclei; the hadronic double scattering operator; pion scattering and charge exchange from polarized nuclei; pion absorption in nuclei; modification of nucleon structure in nuclei; and antiproton annihilation in nuclei
International Nuclear Information System (INIS)
Eyraud, L; Furget, C.; Goy, J.; Kox, S.; Merchez, F.; Pastor, A.; Real, J.S.; Russew, T.; Tieulent, R.; Voutier, E.
1997-01-01
Over these two years, our group has been worked in hadronic physics at Saturn and CEBAF using the polarimeter POLDER. Tensor polarization observables have been measured in the reaction H(p bar, d bar)π + between 580 and 1300 MeV proton energy. The group has also been leader in an experiment, performed in 1997 at CEBAF. By measuring the t 20 polarization of the recoil deuteron produced in the elastic electron-deuteron scattering at large Q 2 , the separation of the charge and quadrupole form-factors of the deuteron will be performed for Q=4.1-6.8 fm -1 . Finally, we were involved in the construction and test of the neutron polarimeter HARP and in the definition of the physics program of the ELFE project. (authors)
Approximation of hadron interactions by Regge diagrams with multipomeron exchange
International Nuclear Information System (INIS)
Barashenkov, V.S.
1988-01-01
A good agreement of hadron diffraction interaction total cross section and their elastic scattering at small angles calculated by summarizing Regge multipomeron exchange diagrams with experiment mentioned by a number of authors results from the fitting of a great variety of the parameters contained in the formulas. The agreement of the other hadron characteristcs with experiment is worse. Distribution of hadron interactions over the number of fragmenting quark-gluon strings calculated by utilizing Regge diagrams is discussed
A field theory for composite particles (hadrons): Pt. 2
International Nuclear Information System (INIS)
Biswas, T.
1986-01-01
Interaction between composite units (hadrons) is introduced in a fashion similar to QED. Quark-quark interactions within hadrons are considered to be of direct-interaction nature. This provides a completely relativistic and self-consistent theory for strong interactions that can be used as a tool for phenomenology. Hadron scattering and bound states have a simple description and their computation is expected to be laborious but straightforward
Hard scattering and jet physics in connection with real photons
International Nuclear Information System (INIS)
Pretzl, K.P.
1983-01-01
This report contains a summary of the physics discussed in the working groups on (a) jet physics at the SPS in hadron-hadron collisions, (b) hard scattering with incident real photons and (c) large psub(T) prompt photons in hadron-hadron collisions. (orig.)
How to detect colour field topologies in hadronic interactions
International Nuclear Information System (INIS)
Andersson, B.; Bengtsson, H.U.
1987-06-01
We discuss the different colour field topologies of QCD interactions, and demonstrate how the existence of two different colour topologies in qg scattering will lead to an experimentally observable asymmetry in the production of K + K - pairs in hadron-hadron collisions. (authors)
Multidimensional study of hadronization in nuclei
Energy Technology Data Exchange (ETDEWEB)
Airapetian, A. [Giessen Univ. (Germany). Physikalisches Inst.; Michigan Univ., Ann Arbor, MI (United States). Randall Lab. of Physics; Akopov, N. [Yerevan Physics Institute (Armenia); Akopov, Z. [DESY Hamburg (DE)] (and others)
2011-07-15
Hadron multiplicities in semi-inclusive deep-inelastic scattering were measured on neon, krypton and xenon targets relative to deuterium at an electron(positron)-beam energy of 27.6 GeV at HERMES. These ratios were determined as a function of the virtual-photon energy {nu}, its virtuality Q{sup 2}, the fractional hadron energy z and the transverse hadron momentum with respect to the virtual-photon direction p{sub t}. Dependences were analysed separately for positively and negatively charged pions and kaons as well as protons and antiprotons in a two-dimensional representation. Compared to the one-dimensional dependences, some new features were observed. In particular, when z>0:4 positive kaons do not show the strong monotonic rise of the multiplicity ratio with {nu} as exhibited by pions and K{sup -}. Protons were found to behave very differently from the other hadrons. (orig.)
Meißner, Ulf-G.
2004-01-01
The status of hadron physics at the end of the HADRON07 Conference is reviewed. The latest results presented at the conference, as well as those important developments in the field which were not represented, are included.
QCD in hadron-hadron collisions
International Nuclear Information System (INIS)
Albrow, M.
1997-03-01
Quantum Chromodynamics provides a good description of many aspects of high energy hadron-hadron collisions, and this will be described, along with some aspects that are not yet understood in QCD. Topics include high E T jet production, direct photon, W, Z and heavy flavor production, rapidity gaps and hard diffraction
COMPASS hadron multiplicity measurements and fragmentation functions
International Nuclear Information System (INIS)
Stolarski, M.
2016-01-01
COMPASS is an experiment located at CERN SPS accelerator. For the results presented in this paper a 160 GeV positive muon beam was impinging on 6 LiD target. The COMPASS spectrometer was designed to reconstruct scattered muons and charged hadrons in a wide kinematic range. COMPASS preliminary results on hadron, pion and kaon multiplicities are presented. The hadron and pion data show a good agreement with (N)LO QCD expectations and some of these preliminary data have been already successfully incorporated in the global NLO QCD fits to world data. However, the results for kaon multiplicities, are different from the expectations of the DSS fit. There is also a tension between COMPASS and HERMES results, the only other experiment which measured kaon multiplicities in Semi-Inclusive Deep Inelastic scattering
International Nuclear Information System (INIS)
Igi, K.
1979-01-01
This paper is related to mini-rapporteur talk on baryonium spectroscopy. First of all, the models of baryonium, namely the diquark model, the string picture, the linear baryonium and the bag model, are described. All of these models so far discussed are highly suggestive. In this paper, discussions are confined to the spectroscopy of the string and the bag models. Because of the color degree of freedom, the bag model has mock diquonium and mock mesonium besides true baryonium. It might be possible that the string model takes into account only a part of them. The constraints among baryonium, baryon and boson trajectories using duality and unitarity were proposed as a guide for classifying various spectra. Inequalities were derived as the modest and reliable constraints on baryonium intercepts from baryon and boson intercepts by imposing unitarity and Regge behaviors on scattering amplitudes. As a consequence of residue factorization and duality, the baryonium slopes were derived. The spin of S (1936) was also obtained. The baryonium containing s or c quarks can also be studied. Topics such as the EXD patterns of baryons, linear baryons, linear Regge trajectories for all Q-anti Q families, and the Al and two Q mesons, are presented in this paper. Comments on di-baryon are described. (Kato, T.)
CMS Central Hadron Calorimeter
Budd, Howard S.
2001-01-01
We present a description of the CMS central hadron calorimeter. We describe the production of the 1996 CMS hadron testbeam module. We show the results of the quality control tests of the testbeam module. We present some results of the 1995 CMS hadron testbeam.
Problems of hadron electrodynamics
International Nuclear Information System (INIS)
Rekalo, M.P.
1989-01-01
Certain directions of hadron electrodynamics referring to testing symmetry properties relatively to C-, P- and T-transformations; determination of fundamental electromagnetic characteristics of hadrons as well as to clarifying the dynamics of electromagnetic processes in which hadrons participate are analyzed briefly. 52 refs
Materials science at an Advanced Hadron Facility
International Nuclear Information System (INIS)
Pynn, R.
1988-01-01
The uses of neutron scattering as a probe for condensed matter phenomena are described briefly and some arguments are given to justify the community's desire for more powerful neutron sources. Appropriate design parameters for a neutron source at an Advanced Hadron Facility are presented, and such a source is compared with other existing and planned spallation neutron sources. 5 refs
Diffractive hard scattering and the SSC
International Nuclear Information System (INIS)
Berger, E.L.; Collins, J.C.; Soper, D.E.; Sterman, G.
1986-01-01
Events in high energy hadron collisions are discussed that contain a hard scattering, in the sense that very heavy quarks or high P/sub T/ jets are produced, yet are diffractive, in the sense that one of the incident hadrons is scattered with only a small energy loss. 12 refs., 6 figs
The hadronic standard model for strong and electroweak interactions
International Nuclear Information System (INIS)
Raczka, R.
1993-01-01
We propose a new model for strong and electro-weak interactions. First, we review various QCD predictions for hadron-hadron and lepton-hadron processes. We indicate that the present formulation of strong interactions in the frame work of Quantum Chromodynamics encounters serious conceptual and numerical difficulties in a reliable description of hadron-hadron and lepton-hadron interactions. Next we propose to replace the strong sector of Standard Model based on unobserved quarks and gluons by the strong sector based on the set of the observed baryons and mesons determined by the spontaneously broken SU(6) gauge field theory model. We analyse various properties of this model such as asymptotic freedom, Reggeization of gauge bosons and fundamental fermions, baryon-baryon and meson-baryon high energy scattering, generation of Λ-polarization in inclusive processes and others. Finally we extend this model by electro-weak sector. We demonstrate a remarkable lepton and hadron anomaly cancellation and we analyse a series of important lepton-hadron and hadron-hadron processes such as e + + e - → hadrons, e + + e - → W + + W - , e + + e - → p + anti-p, e + p → e + p and p + anti-p → p + anti-p processes. We obtained a series of interesting new predictions in this model especially for processes with polarized particles. We estimated the value of the strong coupling constant α(M z ) and we predicted the top baryon mass M Λ t ≅ 240 GeV. Since in our model the proton, neutron, Λ-particles, vector mesons like ρ, ω, φ, J/ψ ect. and leptons are elementary most of experimentally analysed lepton-hadron and hadron-hadron processes in LEP1, LEP2, LEAR, HERA, HERMES, LHC and SSC experiments may be relatively easily analysed in our model. (author). 252 refs, 65 figs, 1 tab
Diffraction scattering of strongly bound system
International Nuclear Information System (INIS)
Kuzmichev, V.E.
1982-04-01
The scattering of a hadron on a strongly bound system of two hadrons (dihadron) is considered in the high-energy limit for the relative hadron-dihadron motion. The dihadron scatterer motion and the internal interaction are included in our consideration. It is shown that only small values of the internal transfer momentum of dihadron particles bring the principal contribution to the three-particle propagator in eikonal approximation. On the basis of the exact analytical solution of the integral equation for the total Green function the scattering amplitude is derived. It is shown that the scattering amplitude contains only single, double, and triple scattering terms. The three new terms to the Glauber formula for the total cross section are obtained. These terms decrease both the true total hadron-hadron cross section and the screening correction. (orig.)
Hadron--hadron reactions, high multiplicity
International Nuclear Information System (INIS)
Diebold, R.
1978-09-01
A coverage of results on high energy and high multiplicity hadron reactions, charm searches and related topics, ultrahigh energy events and exotic phenomena (cosmic rays), and the nuclear effects in high energy collisions and related topics is discussed. 67 references
Diffractive scattering on nuclei in multiple scattering theory with inelastic screening
International Nuclear Information System (INIS)
Zoller, V.R.
1988-01-01
The cross sections for the diffractive scattering of hadrons on nuclei are calculated in the two-channel approximation of multiple scattering theory. In contrast to the standard Glauber approach, it is not assumed that the nucleon scattering profile is a Gaussian or that the Regge radius of the hadron is small compared to the nuclear radius. The AGK Reggeon diagrammatic technique is used to calculate the topological cross sections and the cross sections for coherent and incoherent diffractive dissociation and quasielastic scattering. The features of hadron-nucleus scattering at superhigh energies are discussed
Hadron polarizability data analysis: GoAT
Energy Technology Data Exchange (ETDEWEB)
Stegen, H., E-mail: hkstegen@mta.ca; Hornidge, D. [Mount Allison University, Sackville (Canada); Collicott, C. [Dalhousie University, Halifax (Canada); Martel, P. [Mount Allison University, Sackville (Canada); Johannes Gutenberg University, Mainz (Germany); Ott, P. [Johannes Gutenberg University, Mainz (Germany)
2015-12-31
The A2 Collaboration at the Institute for Nuclear Physics in Mainz, Germany, is working towards determining the polarizabilities of hadrons from nonperturbative quantum chromodynamics through Compton scattering experiments at low energies. The asymmetry observables are directly related to the scalar and spin polarizabilities of the hadrons. Online analysis software, which will give real-time feedback on asymmetries, efficiencies, energies, and angle distributions, has been developed. The new software is a big improvement over the existing online code and will greatly develop the quality of the acquired data.
Hadron polarizability data analysis: GoAT
Stegen, H.; Collicott, C.; Hornidge, D.; Martel, P.; Ott, P.
2015-12-01
The A2 Collaboration at the Institute for Nuclear Physics in Mainz, Germany, is working towards determining the polarizabilities of hadrons from nonperturbative quantum chromodynamics through Compton scattering experiments at low energies. The asymmetry observables are directly related to the scalar and spin polarizabilities of the hadrons. Online analysis software, which will give real-time feedback on asymmetries, efficiencies, energies, and angle distributions, has been developed. The new software is a big improvement over the existing online code and will greatly develop the quality of the acquired data.
Hard processes in hadronic interactions
International Nuclear Information System (INIS)
Satz, H.; Wang, X.N.
1995-01-01
Quantum chromodynamics is today accepted as the fundamental theory of strong interactions, even though most hadronic collisions lead to final states for which quantitative QCD predictions are still lacking. It therefore seems worthwhile to take stock of where we stand today and to what extent the presently available data on hard processes in hadronic collisions can be accounted for in terms of QCD. This is one reason for this work. The second reason - and in fact its original trigger - is the search for the quark-gluon plasma in high energy nuclear collisions. The hard processes to be considered here are the production of prompt photons, Drell-Yan dileptons, open charm, quarkonium states, and hard jets. For each of these, we discuss the present theoretical understanding, compare the resulting predictions to available data, and then show what behaviour it leads to at RHIC and LHC energies. All of these processes have the structure mentioned above: they contain a hard partonic interaction, calculable perturbatively, but also the non-perturbative parton distribution within a hadron. These parton distributions, however, can be studied theoretically in terms of counting rule arguments, and they can be checked independently by measurements of the parton structure functions in deep inelastic lepton-hadron scattering. The present volume is the work of Hard Probe Collaboration, a group of theorists who are interested in the problem and were willing to dedicate a considerable amount of their time and work on it. The necessary preparation, planning and coordination of the project were carried out in two workshops of two weeks' duration each, in February 1994 at CERn in Geneva andin July 1994 at LBL in Berkeley
Hadron correlations from recombination
Energy Technology Data Exchange (ETDEWEB)
Fries, Rainer J [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)
2005-01-01
Quark recombination is a successful model to describe the hadronization of a deconfined quark gluon plasma. Jet-like dihadron correlations measured at RHIC provide a challenge for this picture. We discuss how correlations between hadrons can arise from correlations between partons before hadronization. An enhancement of correlations through the recombination process, similar to the enhancement of elliptic flow is found. Hot spots from completely or partially quenched jets are a likely source of such parton correlations.
International Nuclear Information System (INIS)
Wiedner, Ulrich
2011-01-01
The new FAIR facility in Darmstadt has a broad program in the field of hadron and nuclear physics utilizing ion beams with unprecedented intensity and accuracy. The hadron physics program centers around the the high-energy storage ring HESR for antiprotons and the PANDA experiment that is integrated in it. The physics program includes among others topics like hadron spectroscopy in the charmonium mass region and below, hyperon physics, electromagnetic processes and charm in nuclei.
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)
Hadronization of QCD and effective interactions
International Nuclear Information System (INIS)
Frank, M.R.
1994-01-01
An introductory treatment of hadronization through functional integral calculus and bifocal Bose fields is given. Emphasis is placed on the utility of this approach for providing a connection between QCD and effective hadronic field theories. The hadronic interactions obtained by this method are nonlocal due to the QCD substructure, yet, in the presence of an electromagnetic field, maintain the electromagnetic gauge invariance manifest at the quark level. A local chiral model which is structurally consistent with chiral perturbation theory is obtained through a derivative expansion of the nonlocalities with determined, finite coefficients. Tree-level calculations of the pion form factor and π - π scattering, which illustrate the dual constituent-quark-chiral-model nature of this approach, are presented
Behavior of the hadron potential at large distances and properties of the hadron spin-flip amplitude
International Nuclear Information System (INIS)
Predazzi, E.; Selyugin, O.V.
2002-01-01
The impact of the form of the hadron potential at large distances on the behavior of the hadron spin-flip amplitude at small angles is examined. The t-dependence of the spin-flip amplitude of high-energy hadron elastic scattering is analyzed under different assumptions on the hadron interaction. It is shown that the long tail of the nonGaussian form of the hadron potential of the hadron interaction in the impact parameter representation leads to a large value of the slope of the spin-flip amplitude (without the kinematical factor √(vertical stroke t vertical stroke)) as compared with the slope of the spin-nonflip amplitude. This effect can explain the form of the differential cross-section and the analyzing power at small transfer momenta. The methods for the definition of the spin-dependent part of the hadron scattering amplitude are presented. A possibility to investigate the structure of the hadron spin-flip amplitude from the accurate measure of the differential cross-section and the spin correlation parameters is shown. (orig.)
International Nuclear Information System (INIS)
Schwitters, R.F.
1975-01-01
A report is given of the knowledge obtained from SPEAR about hadron production in e + e - annihilation since the discovery of the new particles. Included are the SPEAR magnetic detector, the total cross sections, mean charged multiplicity and energy, inclusive momentum spectra, and hadron angular distribution
International Nuclear Information System (INIS)
Ernst, David J.
1992-01-01
At a Workshop on the Future of Hadron Facilities, held on 15-16 August at Los Alamos National Laboratory, several speakers pointed out that the US physics community carrying out fixed target experiments with hadron beam had not been as successful with funding as it deserved. To rectify this, they said, the community should be better organized and present a more united front
International Nuclear Information System (INIS)
De, S.S.
1989-01-01
The paper deals with the space-time structure of the sub-atomic world and attempts to construct the fields of the constitutents of the hadrons. Then it is attempted to construct the fields of the hadrons from these micro-fields. (autho r). 24 refs
Statistical Hadronization and Holography
DEFF Research Database (Denmark)
Bechi, Jacopo
2009-01-01
In this paper we consider some issues about the statistical model of the hadronization in a holographic approach. We introduce a Rindler like horizon in the bulk and we understand the string breaking as a tunneling event under this horizon. We calculate the hadron spectrum and we get a thermal...
Perspectives in hadron spectroscopy
Energy Technology Data Exchange (ETDEWEB)
Richard, J.M. [Universite Joseph Fourier-IN2P3-CNRS, Lab. de Physique Subatomique et Cosmologie, 38 - Grenoble (France)
2005-07-01
A brief survey is presented of selected recent results on hadron spectroscopy and related theoretical studies. Among the new hadron states, some of them are good candidates for exotic structures: chiral partners of ground-states, hybrid mesons (quark, antiquark and constituent gluon), four-quark states, or meson-meson molecules.
Energy Technology Data Exchange (ETDEWEB)
Ernst, David J.
1992-11-15
At a Workshop on the Future of Hadron Facilities, held on 15-16 August at Los Alamos National Laboratory, several speakers pointed out that the US physics community carrying out fixed target experiments with hadron beam had not been as successful with funding as it deserved. To rectify this, they said, the community should be better organized and present a more united front.
Firetube model and hadron-hadron collisions
International Nuclear Information System (INIS)
Nazareth, R.A.M.S.; Kodama, T.; Portes Junior, D.A.
1992-01-01
A new version of the fire tube model is developed to describe hadron-hadron collisions at ultrarelativistic energies. Several improvements are introduced in order to include the longitudinal expansion of intermediate fireballs, which remedies the overestimates of the transverse momenta in the previous version. It is found that, within a wide range of incident energies, the model describes well the experimental data for the single particle rapidity distribution, two-body correlations in the pseudo-rapidity, transverse momentum spectra of pions and kaons, the leading particle spectra and the K/π ratio. (author)
International Nuclear Information System (INIS)
Strugalski, Z.
1981-01-01
Qualitative picture of high energy hadron-nucleus collision process, emerging from the analysis of experimental data, is presented. Appropriate description procedure giving a possibility of reproducing various characteristics of this process in terms of the data on elementary hadron-nucleon interaction is proposed. Formula reproducing hadron-nucleus collision cross sections is derived. Inelastic collision cross sections for pion-nucleus and proton-nucleus reactions at wide energy interval are calculated for Pb, Ag, and Al targets. A-dependence of cross sections for pion-nucleus and proton-nucleus collisions at nearly 50 GeV/c momentum were calculated and compared with existing experimental data. Energy dependence of cross sections for hadron-nucleus collisions is determined simply by energy dependence of corresponding cross sections for hadron-nucleon collisions; A-dependence is determined simply by nuclear sizes and nucleon density distributions in nuclei
Inelastic hadron reactions using a streamer chamber triggered by a single-arm spectrometer
2002-01-01
This experiment will investigate hard hadron-hadron collisions where a large fraction of the total energy is carried off at large angles with respect to the incident beam direction. The measurements will be done in the energy range of 200-400 GeV and with various hadrons ($\\pi^{\\pm}, K^{\\pm}, p, \\bar{p}$) incident on a liquid-hydrogen target. \\\\ \\\\The following questions will be investigated: \\\\ \\\\i) Is there a scaling law in hard hadron-hadron collisions which is similar to the scaling laws observed in lepton-hadron and $e^{+}e^{-}$ collisions? \\\\ ii) What do the multiparticle final states look like? Are there jets and if so do they reflect the parton structure of hadrons? Do the final states produced in deep inelastic hadron-hadron scattering look similar to those produced in deep inelastic lepton-hadron scattering? \\\\ iii) Are heavy objects and/or new quantum numbers produced in hard hadron-hadron collisions? \\\\ \\\\The apparatus comprises a vertex magnet (1 m gap, 2 m diameter, 15 kG) with a 30 cm long hyd...
Jet and hadron production in photon-photon collisions
Soldner-Rembold, Stefan
1999-01-01
Di-jet and inclusive charged hadron production cross-sections measured in photon-photon collisions by OPAL are compared to NLO pQCD calculations. Jet shapes measured in photon-photon scattering by OPAL, in deep-inelastic ep scattering by H1 and in photon-proton scattering by ZEUS are shown to be consistent in similar kinematic ranges. New results from TOPAZ on prompt photon production in photon-photon interactions are presented.
Energy Technology Data Exchange (ETDEWEB)
Gauron, Pierre; Basarab Nicolescu [Theoretical Physics Division, Inst. de Physique Nucleaire, Paris-11 Univ., 91 - Orsay (France); Selyugin, O.V. [Lab. of Theoretical Physics, Joint Inst. for Nuclear Research, Dubna (Russian Federation)
1999-10-01
It is shown that the measurement of the polarization together with the hadron elastic dN/dt distribution of the Coulomb nuclei interference region allows to extract directly from the data both the real and imaginary parts of the spin-non-flip nuclear amplitude independently of each other and without any arbitrary theoretical assumption. The crucial parameter {rho} = ReF/ImF will be therefore known as a function of t at fixed s and will allow us to detect new phenomena in hadron physics. (authors)
Polarization in high Psub(trans) and cumulative hadron production
International Nuclear Information System (INIS)
Efremov, A.V.
1978-01-01
The final hadron polarization in the high Psub(trans) processes is analyzed in the parton hard scattering picture. Scaling assumption allows a correct qualitative description to be given for the Psub(trans)-behaviour of polarization or escape angle behaviour in cumulative production. The energy scaling and weak dependence on the beam and target type is predicted. A method is proposed for measuring the polarization of hadron jets
From magnetized iron bars to amplitude imaging of hadronic reactions
International Nuclear Information System (INIS)
Svec, M.
1989-01-01
Instruments shape research and determine which discoveries are made. Considering spin observables as carriers of information on nonperturbative QCD dynamics in hadronic reactions, we examine the relevance of amplitude analysis for the design goals of high intensity hadron facilities. New instrumental goals emerge: Hadron facility dedicated to continous measurements of spin observables and to cumulative production of computer images of scattering amplitudes over broad kinematic regions. The facility is viewed as a single instrument and termed spinoscope. We stress its connections to frontier developments in computer industries and to studies of nonperturbative states in condensed 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}.
International Nuclear Information System (INIS)
Anon.
1987-01-01
With much particle physics research using particle beams to probe the behaviour of the quark constituents deep inside nucleons and other strongly interacting particles (hadrons), it is easy to overlook the progress being made through hadron spectroscopy – the search for and classification of rare particles – and the way it has increased our understanding of quark physics. One way of remedying this was to attend the stimulating and encouraging Hadron 87 meeting held earlier this year at the Japanese KEK Laboratory, where Jonathan Rosner from Chicago's Enrico Fermi Institute gave the concluding talk
Hadron accelerators in medicine
International Nuclear Information System (INIS)
Amaldi, U.
1996-01-01
The application of hadron accelerators (protons and light ions) in cancer therapy is discussed. After a brief introduction on the rationale for the use of heavy charged particles in radiation therapy, a discussion is given on accelerator technology and beam delivery systems. Next, existing and planned facilities are briefly reviewed. The Italian Hadron-therapy Project is then described in some detail, with reference ro both the National Centre for Oncological Hadron-therapy and the design of different types of compact proton accelerators aimed at introducing proton therapy in a large umber of hospitals. (author)
Energy Technology Data Exchange (ETDEWEB)
Anon.
1987-09-15
With much particle physics research using particle beams to probe the behaviour of the quark constituents deep inside nucleons and other strongly interacting particles (hadrons), it is easy to overlook the progress being made through hadron spectroscopy – the search for and classification of rare particles – and the way it has increased our understanding of quark physics. One way of remedying this was to attend the stimulating and encouraging Hadron 87 meeting held earlier this year at the Japanese KEK Laboratory, where Jonathan Rosner from Chicago's Enrico Fermi Institute gave the concluding talk.
Leading Hadron Production at HERA
Directory of Open Access Journals (Sweden)
Buniatyan Armen
2013-06-01
Full Text Available Data from the recent measurements of very forward baryon and photon production with the H1 and ZEUS detectors at electron-proton collider HERA are presented and compared to the theoretical calculations and Monte Carlo models. Results are presented of the production of leading protons, neutrons and photons in deep inelastic scattering (ep → e' pX, ep → e'nX, ep → e'γX as well as the leading neutron production in the photoproduction of dijets (ep → ejjXn. The forward baryon and photon results from the H1 and ZEUS Experiments are compared also with the models of the hadronic interactions of high energy Cosmic Rays. The sensitivity of the HERA data to the differences between the models is demonstrated.
International Nuclear Information System (INIS)
Kaplan, D.B.
1995-01-01
I give a brief and selective overview of QCD as it pertains to determining hadron structure, and the relevant directions in this field for nuclear theory. This document is intended to start discussion about priorities, not end it
International Nuclear Information System (INIS)
Ferbel, T.
1976-01-01
Recent experimental results from studies of hadron interactions at Fermilab are surveyed. Elastic, total and charge-exchange cross section measurements, diffractive phenomena, and inclusive production, using nuclear as well as hydrogen targets, are discussed in these lectures
Energy Technology Data Exchange (ETDEWEB)
NONE
2006-07-01
The following topics were ealt with: Hadron physics with proton and deuteron probes, physics projects with Georgian participation, spin physics with antiprotons and leptons, spin filtering experiments, ISTC projects, technical issues for FAIR. (HSI)
Interplay among transversity induced asymmetries in hadron leptoproduction
Directory of Open Access Journals (Sweden)
C. Adolph
2016-02-01
Full Text Available In the fragmentation of a transversely polarized quark several left–right asymmetries are possible for the hadrons in the jet. When only one unpolarized hadron is selected, it exhibits an azimuthal modulation known as the Collins effect. When a pair of oppositely charged hadrons is observed, three asymmetries can be considered, a di-hadron asymmetry and two single hadron asymmetries. In lepton deep inelastic scattering on transversely polarized nucleons all these asymmetries are coupled with the transversity distribution. From the high statistics COMPASS data on oppositely charged hadron-pair production we have investigated for the first time the dependence of these three asymmetries on the difference of the azimuthal angles of the two hadrons. The similarity of transversity induced single and di-hadron asymmetries is discussed. A new analysis of the data allows quantitative relationships to be established among them, providing for the first time strong experimental indication that the underlying fragmentation mechanisms are all driven by a common physical process.
Hadronic production of glueballs
International Nuclear Information System (INIS)
Lindenbaum, S.J.
1983-01-01
Local Gauge Invariance of SU(3)/sub c/ and color confinement would require that the only hadrons in the world be glueballs. However, when we add the quarks and obtain QCD it is experimentally clear that quark built states mask the expected glueballs. Thus discovery of glueballs is essential for the viability of QCD. Papers presented at the 1983 International Europhysics Conference on High Energy Physics on the hadronic production of glueballs and searches for glueballs are reviewed
Banfi, Andrea
2016-01-01
Jet physics is an incredibly rich subject detailing the narrow cone of hadrons and other particles produced by the hadronization of a quark or gluon in a particle physics or heavy ion experiment. This book is a general overview of jet physics for scientists not directly involved in the field. It presents the basic experimental and theoretical problems arising when dealing with jets, and describing the solutions proposed in recent years.
International Nuclear Information System (INIS)
Martin, F.
1981-03-01
The x dependence of hadron structure functions is investigated. If quarks can exist in very low mass states (10 MeV for d and u quarks) the pion structure function is predicted to behave like (1-x) and not (1-x) 2 in a x-region around 1. Relativistic and non-relativistic quark bound state pictures of hadrons are considered together with their relation with the Q 2 evolution of structure functions. Good agreement with data is in general obtained
International Nuclear Information System (INIS)
Greenberg, O.W.; Nelson, C.A.
1977-01-01
The evidence for a three-valued 'color' degree of freedom in hadron physics is reviewed. The structure of color models is discussed. Consequences of color models for elementary particle physics are discussed, including saturation properties of hadronic states, π 0 →2γ and related decays, leptoproduction, and lepton pair annihilation. Signatures are given which distinguish theories with isolated colored particles from those in which color is permanently bound. (Auth.)
Narison, Stephan
2007-07-01
About Stephan Narison; Outline of the book; Preface; Acknowledgements; Part I. General Introduction: 1. A short flash on particle physics; 2. The pre-QCD era; 3. The QCD story; 4. Field theory ingredients; Part II. QCD Gauge Theory: 5. Lagrangian and gauge invariance; 6. Quantization using path integral; 7. QCD and its global invariance; Part III. MS scheme for QCD and QED: Introduction; 8. Dimensional regularization; 9. The MS renormalization scheme; 10. Renormalization of operators using the background field method; 11. The renormalization group; 12. Other renormalization schemes; 13. MS scheme for QED; 14. High-precision low-energy QED tests; Part IV. Deep Inelastic Scattering at Hadron Colliders: 15. OPE for deep inelastic scattering; 16. Unpolarized lepton-hadron scattering; 17. The Altarelli-Parisi equation; 18. More on unpolarized deep inelastic scatterings; 19. Polarized deep-inelastic processes; 20. Drell-Yan process; 21. One 'prompt photon' inclusive production; Part V. Hard Processes in e+e- Collisions: Introduction; 22. One hadron inclusive production; 23. gg scatterings and the 'spin' of the photon; 24. QCD jets; 25. Total inclusive hadron productions; Part VI. Summary of QCD Tests and as Measurements; Part VII. Power Corrections in QCD: 26. Introduction; 27. The SVZ expansion; 28. Technologies for evaluating Wilson coefficients; 29. Renormalons; 30. Beyond the SVZ expansion; Part VIII. QCD Two-Point Functions: 31. References guide to original works; 32. (Pseudo)scalar correlators; 33. (Axial-)vector two-point functions; 34. Tensor-quark correlator; 35. Baryonic correlators; 36. Four-quark correlators; 37. Gluonia correlators; 38. Hybrid correlators; 39. Correlators in x-space; Part IX. QCD Non-Perturbative Methods: 40. Introduction; 41. Lattice gauge theory; 42. Chiral perturbation theory; 43. Models of the QCD effective action; 44. Heavy quark effective theory; 45. Potential approaches to quarkonia; 46. On monopole and confinement; Part X. QCD
Quark-model study of the hadron structure and the hadron-hadron interaction
International Nuclear Information System (INIS)
Valcarce, A; Caramés, T F; Vijande, J; Garcilazo, H
2011-01-01
Recent results of hadron spectroscopy and hadron-hadron interaction within a quark model framework are reviewed. Higher order Fock space components are considered based on new experimental data on low-energy hadron phenomenology. The purpose of this study is to obtain a coherent description of the low-energy hadron phenomenology to constrain QCD phenomenological models and try to learn about low-energy realizations of the theory.
Artificial Neural Networks For Hadron Hadron Cross-sections
International Nuclear Information System (INIS)
ELMashad, M.; ELBakry, M.Y.; Tantawy, M.; Habashy, D.M.
2011-01-01
In recent years artificial neural networks (ANN ) have emerged as a mature and viable framework with many applications in various areas. Artificial neural networks theory is sometimes used to refer to a branch of computational science that uses neural networks as models to either simulate or analyze complex phenomena and/or study the principles of operation of neural networks analytically. In this work a model of hadron- hadron collision using the ANN technique is present, the hadron- hadron based ANN model calculates the cross sections of hadron- hadron collision. The results amply demonstrate the feasibility of such new technique in extracting the collision features and prove its effectiveness
Analysis of elastic interactions of hadrons at high energies
International Nuclear Information System (INIS)
Yuldashev, B.S.; Fazilova, Z.F.; Ismatov, E.I.; Kurmanbai, M.S.; Ajniyazova, G.T.; Tskhay, K.V.; Medeuova, A.B.
2004-01-01
Study of elastic interactions of hadrons at high energies if of great interest due to the fact that the amplitude of this process is the simplest, and at the same time, it is a fundamental object for theoretical and experimental researches. Study of this process allows one to have a quantitative check of various theories and models, and to make a critical selection. By using of fundamental property of theory - unitarity condition of scattering matrix - elastic scattering can be connected with inelastic reaction. Based on S-channel unitarity condition expressing elastic amplitude via inelastic overlapping function, to study the latter, as well as to describe the experimentally measured characteristics of hadron-nucleon interactions at high-energies, as well as for results prediction. By using experimental data on differential cross-section of elastic scattering of hadrons at various energies and by theoretical information on ratio of a real part and an imaginary part of scattering amplitude δ(t) the t-dependence of inelastic and elastic overlapping functions is studied. Influence of a zigzag form of differential cross-section of elastic pp(p) scattering on profile function and inelastic overlapping function to violation of geometric scaling was studied. In frames of the scaling the general expressions for s- and t-dependences of inelastic overlapping function are derived. Comparison of this function in three elastic scattering models was carried out. It was demonstrated that one would need to assume that hadrons become blacker at central part in order to correctly describe experimental angular distribution data. Dependence of differential cross-section on transfer momentum square for elastic hadrons scattering at energies of ISR and SPS in the model of inelastic overlapping function is studied. (author)
Analysis of elastic interactions of hadrons at high energies
International Nuclear Information System (INIS)
Fazylov, M.I.; Yuldashev, B.S.; Azhniyazova, G.T.; Ismatov, E.I.; Sartbay, T.; Kurmanbay, M.S.; Tskhay, K.V.
2004-01-01
Full text: Study of elastic interactions of hadrons at high energies if of great interest due to the fact that the amplitude of this process is the simplest, and at the same time, it is a fundamental object for theoretical and experimental researches. Study of this process allows one to have a quantitative check of various theories and models, and to make a critical selection. By using of fundamental property of theory - unitarity condition of scattering matrix - elastic scattering can be connected with inelastic reaction. Based on S-channel unitarity condition expressing elastic amplitude via inelastic overlapping function, to study the latter, as well as to describe the experimentally measured characteristics of hadron-nucleon interactions at high-energies, as well as for results prediction. By using experimental data on differential cross-section of elastic scattering of hadrons at various energies and by theoretical information on ratio of a real part and an imaginary part of scattering amplitude δ(t) the t-dependence of inelastic and elastic overlapping functions is studied. Influence of a zigzag form of differential cross-section of elastic pp(p) scattering on profile function and inelastic overlapping function to violation of geometric scaling was studied. In frames of the scaling the general expressions for s- and t-dependences of inelastic overlapping function are derived. Comparison of this function in three elastic scattering models was carried out. It was demonstrated that one would need to assume that hadrons become blacker at central part in order to correctly describe experimental angular distribution data. Dependence of differential cross-section on transfer momentum square for elastic hadrons scattering at energies of ISR and SPS in the model of inelastic overlapping function is studied
Light-Front Dynamics in Hadron Physics
International Nuclear Information System (INIS)
Ji, C.-R.; Bakker, B.L.G.; Choi, H.-M.
2013-01-01
Light-front dynamics(LFD) plays an important role in the analyses of relativistic few-body systems. As evidenced from the recent studies of generalized parton distributions (GPDs) in hadron physics, a natural framework for a detailed study of hadron structures is LFD due to its direct application in Minkowski space as well as its distinct feature of accounting for the vacuum fluctuations in quantum field theories. In the last few years, however, it has been emphasized that treacherous points such as LF singularities and zero-modes should be taken into account for successful LFD applications to hadron phenomenology. In this paper, we discuss a typical example of the contemporary relativistic hadron physics in which the fundamental issues should be taken into account for the successful application of LFD. In particular, we focus on the kinematic issue of GPDs in deeply virtual Compton scattering (DVCS). Although this fundamental issue has been glossed over in the literature, it must be taken care of for the correct analysis of DVCS data. (author)
Hadron Spectroscopy with COMPASS – Newest Results
Directory of Open Access Journals (Sweden)
Nerling Frank
2012-12-01
Full Text Available The COMPASS experiment at the CERN SPS investigates the structure and spectrum of hadrons by scattering high energetic hadrons and polarised muons off various fixed targets. During the years 2002–2007, COMPASS focused on nucleon spin physics using 160 GeV/c polarised µ+ beams on polarised deuteron and proton targets, including measurements of the gluon contribution to the nucleon spin using longitudinal target polarisation as well as studies of transverse spin effects in the nucleon on a transversely polarised target. One major goal of the physics programme using hadron beams is the search for new states, in particular the search for JPC exotic states and glue-balls. COMPASS measures not only charged but also neutral final-state particles, allowing for investigation of new objects in different reactions and decay channels. In addition COMPASS can measure low-energy QCD constants like, e.g. the electromagnetic polarisability of the pion. Apart from a few days pilot run data taken in 2004 with a 190 GeV/c π− beam on a Pb target, showing a significant spin-exotic JPC = 1−+ resonance at around 1660 MeV/c2, COMPASS collected high statistics with negative and positive 190 GeV/c hadron beams on a proton (H2 and nuclear (Ni, Pb targets in 2008 and 2009. We give a selected overview of the newest results and discuss the status of various ongoing analyses.
Geometric branching model of high-energy hadron-hadron collisions
International Nuclear Information System (INIS)
Chen, W.
1988-01-01
A phenomenological model is proposed to describe collisions between hadrons at high energies. In the context of the eikonal formalism, the model consists of two components: soft and hard. The former only involves the production of particles with small transverse momenta; the latter is characterized by jet production. Geometrical scaling is taken as an essential input to describe the geometrical properties of hadrons as extended objects on the one hand, and on the other to define the soft component in both regions below and above the jet threshold. A stochastical Furry branching process is adopted as the mechanism of soft particle production, while the jet fragmentation and gluon initial-state bremsstrahlung are for the production of hadrons in hard collisions. Impact parameter and virtuality are smeared to describe the statistical averaging effects of hadron-hadron collisions. Many otherwise separated issues, ranging from elastic scattering to parton decay function, are connected together in the framework of this model. The descriptions of many prominent features of hadronic collisions are in good agreement with the observed experimental data at all available energies. Multiplicity distributions at all energies are discussed as a major issue in this paper. KNO scaling is achieved for energies within ISR range. The emergence of jets is found to be responsible not only for the violation of both geometrical scaling and KNO scaling, but also for the continuous broadening of the multiplicity distribution with ever increasing energy. It is also shown that the geometrical size of a hadron reaches an asymptote in the energy region of CERN-SppS. A Monte Carlo version of the model for soft production is constructed
2009-01-01
The CERN Dragon Boat team – the Hadron Dragons – achieved a fantastic result at the "Paddle for Cancer" Dragon Boat Festival at Lac de Joux on 6 September. CERN Hadron Dragons heading for the start line.Under blue skies and on a clear lake, the Hadron Dragons won 2nd place in a hard-fought final, following top times in the previous heats. In a close and dramatic race – neck-and-neck until the final 50 metres – the local Lac-de-Joux team managed to inch ahead at the last moment. The Hadron Dragons were delighted to take part in this festival. No one would turn down a day out in such a friendly and fun atmosphere, but the Dragons were also giving their support to cancer awareness and fund-raising in association with ESCA (English-Speaking Cancer Association of Geneva). Riding on their great success in recent competitions, the Hadron Dragons plan to enter the last Dragon Boat festival of 2009 in Annecy on 17-18 October. This will coincide with t...
Hadron dynamics at high energies
International Nuclear Information System (INIS)
Storrow, J.K.
1977-01-01
The nine lectures give a very brief introduction to hadron dynamics at high energies. They concentrate on basic concepts such as Regge poles, duality and geometrical ideas, and simple applications of these ideas to the problem of understanding data. To some extent two body phenomenology is emphasized at the expense of multiparticle final states and when the latter have been considered they have concentrated on inclusive reactions. One lecture discussed data on 2-2 reactions in order to provide the motivation for Regge pole theory, then two lectures are devoted to basic concepts. Then duality is introduced and shown to provide reasonable restrictions on a pole model. A lecture is then devoted to discussing geometrical ideas i.e. the t-dependence of data is looked at from an s-channel point of view. The section on two-body phenomenology is then concluded by discussing applications of the above ideas to two reactions-pion-nucleon scattering and np charge exchange scattering. The remaining three lectures are devoted to multiparticle reactions. Exclusive reactions are considered briefly and then the remainder of the course is concerned with inclusive reactions. The concepts of scaling and limiting fragmentation are discussed and Mueller's generalised optical theorem introduced and then applied in various kinematic limits. (author)
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.
Mallik, Samirnath
2016-01-01
High energy laboratories are performing experiments in heavy ion collisions to explore the structure of matter at high temperature and density. This elementary book explains the basic ideas involved in the theoretical analysis of these experimental data. It first develops two topics needed for this purpose, namely hadron interactions and thermal field theory. Chiral perturbation theory is developed to describe hadron interactions and thermal field theory is formulated in the real-time method. In particular, spectral form of thermal propagators is derived for fields of arbitrary spin and used to calculate loop integrals. These developments are then applied to find quark condensate and hadron parameters in medium, including dilepton production. Finally, the non-equilibrium method of statistical field theory to calculate transport coefficients is reviewed. With technical details explained in the text and appendices, this book should be accessible to researchers as well as graduate students interested in thermal ...
International Nuclear Information System (INIS)
Chela-Flores, J.
1981-08-01
A many-body approach to hadron structure is presented, in which we consider two parton species: spin-0 (b-partons), and spin-1/2 (f-partons). We extend a boson and a fermion pairing scheme for the b-, and f-partons respectively, into a Yang-Mills gauge theory. The main feature of this theory is that the gauge field is not identified with the usual gluon field variable in QCD. We study the confinement problem of the hadron constituents, and obtain, for low temperatures, partons that are confined by energy gaps. As the critical temperatures for the corresponding phase transitions are approached, the energy gap gradually disappears, and confinement is lost. The theory goes beyond the non-relativistic harmonic oscillator quark model, in the sense of giving physical reasons why a non-relativistic approximation is adequate in describing the internal dynamics of hadron structure. (author)
Elastic diffraction interactions of hadrons at high energies
International Nuclear Information System (INIS)
Ismatov, E.I.; Ubaev, J.K.; Tshay, K.V.; Zholdasova, S.M.; Juraev, Sh.Kh.; Essaniazov, Sh.P.
2006-01-01
Full text: 1. The diffraction theory of elastic and inelastic scattering of hadron-hadron and hadron-nucleus processes is developed. The description of experimental data on differential cross section of elastic scattering p p, p-bar p in wide range of transferred momentum is made in the frames of the developed inelastic overlap function model. The investigation of nuclei elastic scattering at the low, middle and high energies is carried out, that allowed to execute quantitative control of efficiency or quantum-field and phenomenological theories and make critical analysis of their utility. The principle of construction of realistic amplitudes of the elastic scattering is confirmed on the basic of the s- and t-channel approaches both conditions stationary of amplitudes. For a wide range of models the comparative analysis of amplitude of inelastic scattering in representation of impact parameter is executed. The expression for effective radius of interaction, effective trajectory Regge and slope of inelastic function of overlapping are analysed. In diffraction approximation the satisfactory description of the data on hadrons interaction at the energy of tens GeV with proton and deuterons is received. The features of spectra of fast particles are analysed. The theory of collective variables S, T, P which characterize a deviation degree of angular distribution of particles from spherical symmetry, the general formula for dispersion of any density of obtained, the particles decays are investigated [1-2]. 2. The solution of Lippmann-Schwinger equation investigated within the frameworks of frameworks of high -energy approximation satisfies the generalized Huygens principle used in the diffraction theory nuclear processes. The diffraction emission is considered at the interaction of charged hadrons one with another and the nuclei [3]. 3. Study of elastic interactions of hadrons at high energies is of great interest due to the fact that the amplitude of this process is the
Di-hadron azimuthal correlation and Mach-like cone structure in a parton/hadron transport model
International Nuclear Information System (INIS)
Ma, G.L.; Zhang, S.; Ma, Y.G.; Huang, H.Z.; Cai, X.Z.; Chen, J.H.; He, Z.J.; Long, J.L.; Shen, W.Q.; Shi, X.H.; Zuo, J.X.
2006-01-01
In the framework of a multi-phase transport model (AMPT) with both partonic and hadronic interactions, azimuthal correlations between trigger particles and associated scattering particles have been studied by the mixing-event technique. The momentum ranges of these particles are 3 T trig T assoc T trig T assoc NN =200 GeV. A Mach-like structure has been observed in correlation functions for central collisions. By comparing scenarios with and without parton cascade and hadronic rescattering, we show that both partonic and hadronic dynamical mechanisms contribute to the Mach-like structure of the associated particle azimuthal correlations. The contribution of hadronic dynamical process cannot be ignored in the emergence of Mach-like correlations of the soft scattered associated hadrons. However, hadronic rescattering alone cannot reproduce experimental amplitude of Mach-like cone on away-side, and the parton cascade process is essential to describe experimental amplitude of Mach-like cone on away-side. In addition, both the associated multiplicity and the sum of p T decrease, while the T > increases, with the impact parameter in the AMPT model including partonic dynamics from string melting scenario
The hadronic standard model for strong and electroweak interactions
Energy Technology Data Exchange (ETDEWEB)
Raczka, R. [Soltan Inst. for Nuclear Studies, Otwock-Swierk (Poland)
1993-12-31
We propose a new model for strong and electro-weak interactions. First, we review various QCD predictions for hadron-hadron and lepton-hadron processes. We indicate that the present formulation of strong interactions in the frame work of Quantum Chromodynamics encounters serious conceptual and numerical difficulties in a reliable description of hadron-hadron and lepton-hadron interactions. Next we propose to replace the strong sector of Standard Model based on unobserved quarks and gluons by the strong sector based on the set of the observed baryons and mesons determined by the spontaneously broken SU(6) gauge field theory model. We analyse various properties of this model such as asymptotic freedom, Reggeization of gauge bosons and fundamental fermions, baryon-baryon and meson-baryon high energy scattering, generation of {Lambda}-polarization in inclusive processes and others. Finally we extend this model by electro-weak sector. We demonstrate a remarkable lepton and hadron anomaly cancellation and we analyse a series of important lepton-hadron and hadron-hadron processes such as e{sup +} + e{sup -} {yields} hadrons, e{sup +} + e{sup -} {yields} W{sup +} + W{sup -}, e{sup +} + e{sup -} {yields} p + anti-p, e + p {yields} e + p and p + anti-p {yields} p + anti-p processes. We obtained a series of interesting new predictions in this model especially for processes with polarized particles. We estimated the value of the strong coupling constant {alpha}(M{sub z}) and we predicted the top baryon mass M{sub {Lambda}{sub t}} {approx_equal} 240 GeV. Since in our model the proton, neutron, {Lambda}-particles, vector mesons like {rho}, {omega}, {phi}, J/{psi} ect. and leptons are elementary most of experimentally analysed lepton-hadron and hadron-hadron processes in LEP1, LEP2, LEAR, HERA, HERMES, LHC and SSC experiments may be relatively easily analysed in our model. (author). 252 refs, 65 figs, 1 tab.
The hadronic standard model for strong and electroweak interactions
Energy Technology Data Exchange (ETDEWEB)
Raczka, R [Soltan Inst. for Nuclear Studies, Otwock-Swierk (Poland)
1994-12-31
We propose a new model for strong and electro-weak interactions. First, we review various QCD predictions for hadron-hadron and lepton-hadron processes. We indicate that the present formulation of strong interactions in the frame work of Quantum Chromodynamics encounters serious conceptual and numerical difficulties in a reliable description of hadron-hadron and lepton-hadron interactions. Next we propose to replace the strong sector of Standard Model based on unobserved quarks and gluons by the strong sector based on the set of the observed baryons and mesons determined by the spontaneously broken SU(6) gauge field theory model. We analyse various properties of this model such as asymptotic freedom, Reggeization of gauge bosons and fundamental fermions, baryon-baryon and meson-baryon high energy scattering, generation of {Lambda}-polarization in inclusive processes and others. Finally we extend this model by electro-weak sector. We demonstrate a remarkable lepton and hadron anomaly cancellation and we analyse a series of important lepton-hadron and hadron-hadron processes such as e{sup +} + e{sup -} {yields} hadrons, e{sup +} + e{sup -} {yields} W{sup +} + W{sup -}, e{sup +} + e{sup -} {yields} p + anti-p, e + p {yields} e + p and p + anti-p {yields} p + anti-p processes. We obtained a series of interesting new predictions in this model especially for processes with polarized particles. We estimated the value of the strong coupling constant {alpha}(M{sub z}) and we predicted the top baryon mass M{sub {Lambda}{sub t}} {approx_equal} 240 GeV. Since in our model the proton, neutron, {Lambda}-particles, vector mesons like {rho}, {omega}, {phi}, J/{psi} ect. and leptons are elementary most of experimentally analysed lepton-hadron and hadron-hadron processes in LEP1, LEP2, LEAR, HERA, HERMES, LHC and SSC experiments may be relatively easily analysed in our model. (author). 252 refs, 65 figs, 1 tab.
International Nuclear Information System (INIS)
Ogava, S.; Savada, S.; Nakagava, M.
1983-01-01
Composite models of hadrons are considered. The main attention is paid to the Sakata, S model. In the framework of the model it is presupposed that proton, neutron and Λ particle are the fundamental particles. Theoretical studies of unknown fundamental constituents of a substance have led to the creation of the quark model. In the framework of the quark model using the theory of SU(6)-symmetry the classification of mesons and baryons is considered. Using the quark model relations between hadron masses, their spins and electromagnetic properties are explained. The problem of three-colour model with many flavours is briefly presented
High intensity hadron accelerators
International Nuclear Information System (INIS)
Teng, L.C.
1989-05-01
This rapporteur report consists mainly of two parts. Part I is an abridged review of the status of all High Intensity Hadron Accelerator projects in the world in semi-tabulated form for quick reference and comparison. Part II is a brief discussion of the salient features of the different technologies involved. The discussion is based mainly on my personal experiences and opinions, tempered, I hope, by the discussions I participated in in the various parallel sessions of the workshop. In addition, appended at the end is my evaluation and expression of the merits of high intensity hadron accelerators as research facilities for nuclear and particle physics
International Nuclear Information System (INIS)
Anon.
1987-01-01
'Hadron facilities' – high intensity (typically a hundred microamps), medium energy (30-60 GeV) machines producing intense secondary beams of pions, kaons, etc., are being widely touted as a profitable research avenue to supplement what is learned through the thrust for higher and higher energies. This interest was reflected at an International Workshop on Hadron Facility Technology, held in Santa Fe, New Mexico. As well as invited talks describing the various projects being pushed in the US, Europe and Japan, the meeting included working groups covering linacs, beam dynamics, hardware, radiofrequency, polarized beams and experimental facilities
Correlations in back-to-back hadron production in SIDIS
Energy Technology Data Exchange (ETDEWEB)
Avakian, Harut [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Pisano, Silvia [National Inst. of Nuclear Physics (INFN), Frascati (Italy). National Lab. of Frascati (INFN-LNF)
2016-08-01
The Deep Inelastic Scattering (DIS) proved to be a great tool in testing of the theory of strong in- teractions. Semi-Inclusive DIS (SIDIS), with detection of an additional hadron allowed first stud- ies of 3D structure of the nucleon, moving the main focus from testing the QCD to understanding of strong interactions and quark gluon dynamics to address a number of puzzles accumulated in recent years. Detection of two hadrons in SIDIS, which is even more complicated, provides ac- cess to details of quark gluon interactions inaccessible in single-hadron SIDIS, providing a new avenue to study the complex nucleon structure. Large acceptance of the CLAS detector at Jef- ferson Lab, allowing detection of two hadrons, produced back-to-back (b2b) in the current and target fragmentation regions, provides a unique possibility to study the nucleon structure in target fragmentation region, and correlations of target and current fragmentation regions
Large transverse momenta phenomena in hadron-hadron collisions
International Nuclear Information System (INIS)
McCubbin, N.A.
1981-05-01
The production of particles with large transverse momentum in high energy hadron-hadron collisions is reviewed. The emphasis is placed on the experimental results. These results are discussed in terms of present theoretical ideas on interactions between hadronic constituents, but no attempt is made to review the theoretical work in a comprehensive manner. (author)
Effective hadron degrees of freedom in nuclei
International Nuclear Information System (INIS)
Mulders, P.J.
1988-01-01
This paper discusses several topics. The first one is the importance of a consistent treatment of extended nucleons and the subsequent requirement of accounting for quark antisymmetrization. It will probably be possible to account for these effects through quark exchange currents in much of the same way as meson exchange currents at lower values of Q 2 . In order to obtain more definite answers on intrinsic properties of nucleons and other hadronic degrees of freedom in nuclei it is important to establish to which extent hadronic degrees of freedom behaving like quasi-free nuclear constituents can be used to describe the nuclear response in inclusive and semi-inclusive electron scattering at intermediate energies
High energy hadron-nucleus collision
International Nuclear Information System (INIS)
Takagi, Fujio
1983-02-01
This is a lecture note concerning high energy hadron-nucleus collision. The lecture gives the inelastic total cross section and the Glanber approximate multiple scattering formula at first. The mechanism of nuclear spallation is described in a cylindrical image. The multiplicity, the one particle distribution and the time-space structure of particle production are discussed. Various models are presented. The attenuation of forward particles and the structure of hadrons are discussed for each model. The atomic number (A) dependence of the production of large transverse momentum particles and jet, and the A dependence of charged multiplicity are presented. The backward production of particles and many body correlation are discussed. Lepton pair production and the initial interaction of constituents, collective interaction, multi quark state and phase transition are described. (Kato, T.)
Accelerating and storing polarized hadron beams
International Nuclear Information System (INIS)
Teng, L.C.
1990-10-01
Polarization hadron experiments at high energies continue to generate surprises. Many questions remain unanswered or unanswerable within the frame work of QCD. These include such basic questions as to why at high energies the polarization analyzing power in pp elastic scattering remains high, why hyperons are produced with high polarizations etc. It is, therefore, interesting to investigate the possibilities of accelerating and storing polarized beams in high energy colliders. On the technical side the recent understanding and confirmation of the actions of partial and multiple Siberian snakes made it possible to contemplate accelerating and storing polarized hadron beams to multi-TeV energies. In this paper, we will examine the equipment, the operation and the procedure required to obtain colliding beams of polarized protons at TeV energies
Theory of hadronic production of heavy quarks
International Nuclear Information System (INIS)
Peterson, C.
1981-07-01
Conventional theoretical predictions for hadronic production of heavy quarks (Q anti Q) are reviewed and confronted with data. Perturbative hard scattering predictions agree qualitatively well with hidden Q anti Q production (e.g., psi, chi, T) whereas for open Q anti Q-production (e.g., pp → Λ/sub c/ + X) additional mechanisms or inputs are needed to explain the forwardly produced Λ/sub c/ + at ISR. It is suggested that the presence of c anti c-pairs on the 1 to 2% level in the hadron Fock state decomposition (intrinsic charm) gives a natural description of the ISR data. The theoretical foundations of the intrinsic charm hypotheses together with its consequences for lepton-induced reactions is discussed in some detail
Perspectives in hadron and quark dynamics
International Nuclear Information System (INIS)
Amsler, C.; Bressani, T.; Close, F.E.; De Sanctis, E.; Frois, B.; Kunne, F.; Laget, J.M.; von Harrach, D.; Metag, V.; Mulders, P.J.; Riska, D.O.
1997-01-01
In the past two decades, quantum chromodynamics (QCD) has emerged as the theory for the strong force with quarks and gluons as the building blocks of nuclear matter at large densities and high temperatures. One of the most exciting challenges for nuclear physics is the study of the non-perturbative regime of QCD. It is this regime which is relevant for understanding how the elementary fields of QCD - quarks and gluons - build up particles such as protons and neutrons. A basic theoretical difficulty is the non-existence of asymptotic, isolated, colored objects. This is a feature of the richness of the vacuum structure of QCD. Understanding the different QCD phases and the transitions among them is the challenge of the modern study of strong interactions. At low energy, chiral symmetry can be used to build aneffective theory of hadron interactions. At higher energies, the parton model uses non-perturbative quark and gluon distributions to describe hadronic scattering processes. (orig)
Probing leptophilic dark sectors with hadronic processes
D'Eramo, Francesco; Kavanagh, Bradley J.; Panci, Paolo
2017-08-01
We study vector portal dark matter models where the mediator couples only to leptons. In spite of the lack of tree-level couplings to colored states, radiative effects generate interactions with quark fields that could give rise to a signal in current and future experiments. We identify such experimental signatures: scattering of nuclei in dark matter direct detection; resonant production of lepton-antilepton pairs at the Large Hadron Collider; and hadronic final states in dark matter indirect searches. Furthermore, radiative effects also generate an irreducible mass mixing between the vector mediator and the Z boson, severely bounded by ElectroWeak Precision Tests. We use current experimental results to put bounds on this class of models, accounting for both radiatively induced and tree-level processes. Remarkably, the former often overwhelm the latter.
Calculating hadronic properties in strong QCD
International Nuclear Information System (INIS)
Pennington, M.R.
1996-01-01
This talk gives a brief review of the progress that has been made in calculating the properties of hadrons in strong QCD. In keeping with this meeting I will concentrate on those properties that can be studied with electromagnetic probes. Though perturbative QCD is highly successful, it only applies in a limited kinematic regime, where hard scattering occur, and the quarks move in the interaction region as if they are free, pointlike objects. However, the bulk of strong interactions are governed by the long distance regime, where the strong interaction is strong. It is this regime of length scales of the order of a Fermi, that determines the spectrum of light hadrons and their properties. The calculation of these properties requires an understanding of non-perturbative QCD, of confinement and chiral symmetry breaking. (author)
Recent Developments in Hadron Therapy Accelerators
Klein, Hans-Udo
2005-01-01
In the last decade interest and investments in Hadron Therapy Systems have been steadily increasing resulting in a substantial number of projects currently under construction or entering detailed planning stage. Main routes are pure proton therapy systems and Carbon ion therapy systems which can also run on protons. While the basic accelerator concept for hadron therapy systems is well established there are many considerations on the type and layout of the particle delivery system including the accelerator, an energy selection system, either a fixed beam set up or a rotating gantry, the "nozzle" containing either a scattering or a scanning system, the patient positioner, and all associated control systems. The requirements for the accelerator include most stable beams to match the demand of modern fast scanning systems as well as fast switching between treatment rooms. Currently an ion/proton synchrotron, a pure proton synchrotron, a normalconducting proton cyclotron and a newly developed compact superconduct...
Quark models in hadron physics
International Nuclear Information System (INIS)
Phatak, Shashikant C.
2007-01-01
In this talk, we review the role played by the quark models in the study of interaction of strong, weak and electromagnetic probes with hadrons at intermediate and high momentum transfers. By hadrons, we mean individual nucleons as well as nuclei. We argue that at these momentum transfers, the structure of hadrons plays an important role. The hadron structure of the hadrons is because of the underlying quark structure of hadrons and therefore the quark models play an important role in determining the hadron structure. Further, the properties of hadrons are likely to change when these are placed in nuclear medium and this change should arise from the underlying quark structure. We shall consider some quark models to look into these aspects. (author)
Unitary screening corrections in high energy hadron reactions
Energy Technology Data Exchange (ETDEWEB)
Maor, U
1994-10-01
The role of s-channel unitarity screening corrections, calculated in the eikonal approximation, is investigated for elastic and diffractive hadron-hadron and photon-hadron scattering in the energy limit. We examine the differences between our results and those obtained from the supercritical Pomeron-Reggeon model with no such corrections. It is argued that the saturation of cross sections is attained at different scales for different channels. In particular, we point out that whereas the saturation scale for elastic scattering apparently above the Tevatron energy range, the appropriate diffraction scale is considerably lower and can be assessed with presently available data. A review of the relevant data and its implications is presented. (author). 12 refs, 3 figs, 2 tabs.
Hadron Therapy for Cancer Treatment
International Nuclear Information System (INIS)
Lennox, Arlene
2003-01-01
The biological and physical rationale for hadron therapy is well understood by the research community, but hadron therapy is not well established in mainstream medicine. This talk will describe the biological advantage of neutron therapy and the dose distribution advantage of proton therapy, followed by a discussion of the challenges to be met before hadron therapy can play a significant role in treating cancer. A proposal for a new research-oriented hadron clinic will be presented.
Are Hadrons and Nuclei Open Systems ?
International Nuclear Information System (INIS)
Musulmanbekov, G.
1998-01-01
Fulltext We propose to consider the structure of hadrons in the frame of stochastic interpretation of quantum mechanics, or stochastic theory, which is based on classical mechanics in stochastic environment. This environment is associated with subquantal vacuum. Stochastic theory is a classical physics without the hypothesis that there are isolated systems in the universe. It has been shown by some authors that stochastic theory is justified by fractal space-time considerations. In our approach hadron is a set of embedded into stochastic vacuum (SV) valence quarks (VQ) ( quark-antiquark in mesons and three quarks in baryons ) oscillating near center of proper frame of the hadron VQ being placed into SV behaves itself as a dislocation (antidislocation) in solids or vortex ( antivortex ) in liquids. Effective interaction between VQs comes from specific polarization of SV around VQs leading to outside suppression on VQs. Polarization of SV around VQ characterizes the distribution of hardonic matter inside a hadron. Oscillation motion of VQs around the origin, going from their interaction with SV, is strongly correlated. VQs being in equilibrium with SV exchange energy at all times with it. Neighborhood of two or more nucleons changes SV polarization around their VQs in such a way that they tend to occupy the state with minimum energy arrange crystalline like structure. Therefore the behavior of hadrons and nuclei is typical for open systems exchanging energy with environment .In this approach the relation between constituent (nonrelativistic ) quarks and current ( relativistic) ones becomes clear and transparent, because it composes the features of both NRQM and bag models. It gives qualitative and in some cases quantitative description of experimental facts concerning nucleon and nuclear structure searched in scattering experiments. Some proposals and predictions for future experiments are given
Hadronization of dense partonic matter
Energy Technology Data Exchange (ETDEWEB)
Fries, Rainer J [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)
2006-12-15
The parton recombination model has turned out to be a valuable tool to describe hadronization in high-energy heavy-ion collisions. I review the model and revisit recent progress in our understanding of hadron correlations. I also discuss higher Fock states in the hadrons, possible violations of the elliptic flow scaling and recombination effects in more dilute systems.
Story of the string theory. From hadrons to Planck scale
International Nuclear Information System (INIS)
Petropoulos, P.M.
2010-01-01
Originally the string theory was devised to describe the scattering between hadron particles but was quickly put aside by the success of the quantum chromodynamics. Now string theory appears in the quantum gravity theory and has been involved in almost all attempts to define a physics beyond the standard model and to unify basic interactions. (A.C.)
High-temperature phase transition in hadron matter
International Nuclear Information System (INIS)
Bugrij, A.I.; Trushevsky, A.A.
1976-01-01
A possible phase transition in hadronic systems at temperatures of few of GeV is shown in the framework of the S-matrix formulation of statistical mechanics given by Dashen, Ma, Bernstein by using Regge pole model for the scattering amplitude
Energy Technology Data Exchange (ETDEWEB)
Pondrom, L.
1991-10-03
An introduction to the techniques of analysis of hadron collider events is presented in the context of the quark-parton model. Production and decay of W and Z intermediate vector bosons are used as examples. The structure of the Electroweak theory is outlined. Three simple FORTRAN programs are introduced, to illustrate Monte Carlo calculation techniques. 25 refs.
Bilki, Burak
2018-03-01
The Particle Flow Algorithms attempt to measure each particle in a hadronic jet individually, using the detector providing the best energy/momentum resolution. Therefore, the spatial segmentation of the calorimeter plays a crucial role. In this context, the CALICE Collaboration developed the Digital Hadron Calorimeter. The Digital Hadron Calorimeter uses Resistive Plate Chambers as active media and has a 1-bit resolution (digital) readout of 1 × 1 cm2 pads. The calorimeter was tested with steel and tungsten absorber structures, as well as with no absorber structure, at the Fermilab and CERN test beam facilities over several years. In addition to conventional calorimetric measurements, the Digital Hadron Calorimeter offers detailed measurements of event shapes, rigorous tests of simulation models and various tools for improved performance due to its very high spatial granularity. Here we report on the results from the analysis of pion and positron events. Results of comparisons with the Monte Carlo simulations are also discussed. The analysis demonstrates the unique utilization of detailed event topologies.
Buskulic, Damir; De Bonis, I; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Odier, P; Pietrzyk, B; Ariztizabal, F; Chmeissani, M; Crespo, J M; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Gaitan, V; Martínez, M; Orteu, S; Pacheco, A; Padilla, C; Palla, Fabrizio; Pascual, A; Perlas, J A; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Farilla, A; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Natali, S; Nuzzo, S; Ranieri, A; Raso, G; Romano, F; 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; Bonvicini, G; Cattaneo, M; Comas, P; Coyle, P; Drevermann, H; Engelhardt, A; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Jacobsen, R; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Markou, C; Martin, E B; Mato, P; Minten, Adolf G; Miquel, R; Oest, T; Palazzi, P; Pater, J R; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wiedenmann, W; Wildish, T; Witzeling, W; Wotschack, J; Ajaltouni, Ziad J; Bardadin-Otwinowska, Maria; Barrès, A; Boyer, C; Falvard, A; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rossignol, J M; Saadi, F; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Kyriakis, A; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Passalacqua, L; Rougé, A; Rumpf, M; Tanaka, R; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Delfino, M C; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Pepé-Altarelli, M; Dorris, S J; Halley, A W; ten Have, I; Knowles, I G; Lynch, J G; Morton, W T; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Smith, M G; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Braun, O; Geweniger, C; Graefe, G; Hanke, P; Hepp, V; Kluge, E E; Putzer, A; Rensch, B; Schmidt, M; Sommer, J; Stenzel, H; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Colling, D J; Dornan, Peter J; Konstantinidis, N P; Moneta, L; Moutoussi, A; Nash, J; San Martin, G; Sedgbeer, J K; Stacey, A M; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Bowdery, C K; Brodbeck, T J; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Whelan, E P; Williams, M I; Galla, A; Greene, A M; Kleinknecht, K; Quast, G; Raab, J; Renk, B; Sander, H G; Wanke, R; 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; Thulasidas, M; Nicod, D; Payre, P; Rousseau, D; Talby, M; Abt, I; Assmann, R W; Bauer, C; Blum, Walter; Brown, D; 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; Wolf, G; Alemany, R; Boucrot, J; Callot, O; Cordier, A; Courault, F; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Musolino, G; Nikolic, I A; Park, H J; Park, I C; Schune, M H; Simion, S; Veillet, J J; Videau, I; Abbaneo, 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; Rizzo, G; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Triggiani, G; Vannini, C; Verdini, P G; Walsh, J; Betteridge, A P; Blair, G A; Bryant, L M; Cerutti, F; Gao, Y; Green, M G; Johnson, D L; Medcalf, T; Mir, L M; Perrodo, P; Strong, J A; Bertin, V; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Edwards, M; Maley, P; Norton, P R; Thompson, J C; 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; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Beddall, A; Booth, C N; Boswell, R; Cartwright, S L; Combley, F; Dawson, I; Köksal, A; Letho, M; Newton, W M; Rankin, C; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Feigl, E; Grupen, Claus; Lutters, G; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Ragusa, F; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Bellantoni, L; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Harton, J L; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Schmitt, M; Scott, I J; Sharma, V; Turk, J; Walsh, A M; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G
1996-01-01
From 64492 selected \\tau-pair events, produced at the Z^0 resonance, the measurement of the tau decays into hadrons from a global analysis using 1991, 1992 and 1993 ALEPH data is presented. Special emphasis is given to the reconstruction of photons and \\pi^0's, and the removal of fake photons. A detailed study of the systematics entering the \\pi^0 reconstruction is also given. A complete and consistent set of tau hadronic branching ratios is presented for 18 exclusive modes. Most measurements are more precise than the present world average. The new level of precision reached allows a stringent test of \\tau-\\mu universality in hadronic decays, g_\\tau/g_\\mu \\ = \\ 1.0013 \\ \\pm \\ 0.0095, and the first measurement of the vector and axial-vector contributions to the non-strange hadronic \\tau decay width: R_{\\tau ,V} \\ = \\ 1.788 \\ \\pm \\ 0.025 and R_{\\tau ,A} \\ = \\ 1.694 \\ \\pm \\ 0.027. The ratio (R_{\\tau ,V} - R_{\\tau ,A}) / (R_{\\tau ,V} + R_{\\tau ,A}), equal to (2.7 \\pm 1.3) \\ \\%, is a measure of the importance of Q...
Eytier, Jean-Louis
2009-01-01
Qu'aurait-il proposé comme solutions face aux déboires du LHC, le grand collisionneur du hadrons du CERN, arrêté peu après son démarrage à l'automne 2008? Lucien Edmond André Montanet était un des grands de la physique des particules. (2 pages)
Indian Academy of Sciences (India)
manifestly the symmetries of the underlying theory of strong interactions, i.e. ..... Note that such a picture, in which the self-energies of hadrons are generated by ..... An experimental verification of this prediction would be a major step forward in.
International Nuclear Information System (INIS)
Ilgenfritz, E.M.; Kripfganz, J.; Moehring, H.J.
1977-01-01
The analytical treatment of hadronic decay cascades within the framework of the statistical bootstrap model is demonstrated on the basis of a simple variant. Selected problems for a more comprehensive formulation of the model such as angular momentum conservation, quantum statistical effects, and the immediate applicability to particle production processes at high energies are discussed in detail
Hirstius, Andreas
2008-01-01
Plans for dealing with the torrent of data from the Large Hadron Collider's detectors have made the CERN particle-phycis lab, yet again, a pioneer in computing as well as physics. The author describes the challenges of processing and storing data in the age of petabyt science. (4 pages)
2007-01-01
"In the spring 2008, the Large Hadron Collider (LHC) machine at CERN (the European Particle Physics laboratory) will be switched on for the first time. The huge machine is housed in a circular tunnel, 27 km long, excavated deep under the French-Swiss border near Geneva." (1,5 page)
International Nuclear Information System (INIS)
Pondrom, L.
1991-01-01
An introduction to the techniques of analysis of hadron collider events is presented in the context of the quark-parton model. Production and decay of W and Z intermediate vector bosons are used as examples. The structure of the Electroweak theory is outlined. Three simple FORTRAN programs are introduced, to illustrate Monte Carlo calculation techniques. 25 refs
Hadron production in photon-photon collisions
International Nuclear Information System (INIS)
Pandita, P.N.; Singh, Y.
1976-01-01
We analyze deep-inelastic photon-photon collisions via the two-photon mechanism in electron-positron (-electron) colliding beams in a form especially suitable for experimental analysis. It is shown that by a helicity analysis similar to that used in electroproduction experiments, we can separate five of the eight structure functions describing the process γ* + γ* → hadrons. The helicity cross sections for this process and for the process with one real photon (inelastic electron-photon scattering) are related to structure functions, and are evaluated using quark light-cone algebra. There are anomalous contributions to the structure functions for the inelastic electron-photon scattering which arise both in parton as well as generalized vector-meson-dominance models. This suggests a connection between these two types of models for photon-photon scattering. Further, we use vector-meson dominance to construct a sum rule for sigma/sub gamma//sub gamma/ /sub arrow-right/ from which it is estimated that roughly 20% of the cross section should be built up from higher-mass vector states. Using a spectral representation for the total transverse cross section, and the ''aligned-jet'' vector-dominance model we achieve a connection, via a ''correspondence principle,'' with the parton model for the hadron multiplicities in photon-photon collisions. We also comment on inclusive pion multiplicities and the approach to scaling for photon-photon processes in the light-cone algebra
Polarization experiments with hadronic and electromagnetic probes
International Nuclear Information System (INIS)
Punjabi, V.
1993-01-01
The following research activities were carried out during the past year Calibration of focal plane polarimeter POMME up to 2.4 GeV at Saturne National Laboratory (LNS) in Saclay. Measurement of tensor analyzing power T 20 and polarization transfer κ 0 at Saturne up to 2.1 GeV in elastic backward dp scattering rvec dp → rvec pd. Measurement of tensor analyzing power T 20 at synchrophasotron in Dubha up to 4.4 Gev in elastic backward dp scattering rvec dp → pd. Resubmission of conditionally Approved G EP proposal 89-14 at CEBAF. Start construction of focal plane polarimeter (FPP) for CEBAF hall A hadron spectrometer. The planned work for the next year includes: Construction of FPP for CEBAF hall A hadron spectrometer; measurement of polarization transfer κ 0 and tensor analyzing power T 20 in elastic backward dp scattering at Saturne; measurements of tensor analyzing power in 1 H( 6 Li,d)X, 1 H( 6 Li,α)X, 1 H( 6 Li,t)X and 1 H( 6 Li, 3 He)X reactions at Saturne; and study of polarization transfer in 2 H(rvec e,e'rvec p)n reaction at Bates
Deep-Inelastic Final States in a Space-Time Description of Shower Development and Hadronization
Ellis, John; Geiger, Klaus; Kowalski, Henryk
1996-01-01
We extend a quantum kinetic approach to the description of hadronic showers in space, time and momentum space to deep-inelastic $ep$ collisions, with particular reference to experiments at HERA. We follow the history of hard scattering events back to the initial hadronic state and forward to the formation of colour-singlet pre-hadronic clusters and their decays into hadrons. The time evolution of the space-like initial-state shower and the time-like secondary partons are treated similarly, an...
XXth international workshop on deep-inelastic scattering and related topics. DIS 2012. Proceedings
International Nuclear Information System (INIS)
Brock, Ian C.
2013-03-01
The following topics were dealt with: Structure functions, diffraction and vector mesons, electroweak interactions, hadronic final states, heavy flavours, spin physics, future of deep inelastic scattering. (HSI)
XXth international workshop on deep-inelastic scattering and related topics. DIS 2012. Proceedings
Energy Technology Data Exchange (ETDEWEB)
Brock, Ian C. [ed.
2013-03-15
The following topics were dealt with: Structure functions, diffraction and vector mesons, electroweak interactions, hadronic final states, heavy flavours, spin physics, future of deep inelastic scattering. (HSI)
Institute of Scientific and Technical Information of China (English)
XIONG Wen-Yuan; HU Zhao-Hui; WANG Xin-Wen; ZHOU Li-Juan; XIA Li-Xin; MA Wei-Xing
2008-01-01
Based on analysis of scattering matrix S, and its properties such as analyticity, unitarity, Lorentz invariance, and crossing symmetry relation, the Regge theory was proposed to describe hadron-hadron scattering at high energies before the advent of QCD, and correspondingly a Reggeon concept was born as a mediator of strongly interaction. This theory serves as a successful approach and has explained a great number of experimental data successfully, which proves that the Regge theory can be regarded as a basic theory of hadron interaction at high energies and its validity in many applications. However, as new experimental data come out, we have some difficulties in explaining the data. The new experimental total cross section violates the predictions of Regge theory, which shows that Regge formalism is limited in its applications to high energy data. To understand new experimental measurements, a new exchange theory was consequently born and its mediator is called Pomeron, which has vacuum quantum numbers. The new theory named as Pomeron exchange theory which reproduces the new experimental data of diffractive processes successfully. There are two exchange mediators: Reggeon and Pomeron. Reggeon exchange theory can only produce data at the relatively lower energy region, while Pomeron exchange theory fits the data only at higher-energy region, separately. In order to explain the data in the whole energy region, we propose a Reggeon-Pomeron model to describe high-energy hadron-hadron scattering and other diffractive processes. Although the Reggeon-Pomeron model is successful in describing high-energy hadron-hadron interaction in the whole energy region, it is a phenomenological model After the advent of QCD, people try to reveal the mystery of the phenomenological theory from QCD since hadron-hadron processes is a strong interaction, which is believed to be described by QCD. According to this point of view, we study the QCD nature of Reggeon and Pomeron. We claim
Asymptotic perturbative QCD in elastic scattering, color transparency and ANN
International Nuclear Information System (INIS)
Botts, J.
1989-01-01
Sorting out the various perturbative contributions to wide angel elastic hadron-hadron scattering has been the subject of recent enquiry. Distinguishing the various contributions are the transverse size of the external hadrons and the interaction region and restrictions on the internal momenta flows. For wide angle elastic hadron-hadron scattering, the interaction between two types of perturbative processes, multiple and single scattering, can be the source of interference phenomena and interesting physics. In the following, after a brief description of the leading and non-leading processes, we shall give a picture of what perturbative QCD may have to say about elastic scattering, color transparency and the spin asymmetry, A NN . 9 refs., 5 figs
QCD SPIN PHYSICS IN HADRONIC INTERACTIONS.
Energy Technology Data Exchange (ETDEWEB)
VOGELSANG,W.
2007-06-19
We discuss spin phenomena in high-energy hadronic scattering, with a particular emphasis on the spin physics program now underway at the first polarized proton-proton collider, RHIC. Experiments at RHIC unravel the spin structure of the nucleon in new ways. Prime goals are to determine the contribution of gluon spins to the proton spin, to elucidate the flavor structure of quark and antiquark polarizations in the nucleon, and to help clarify the origin of transverse-spin phenomena in QCD. These lectures describe some aspects of this program and of the associated physics.
Quarks and gluons in hadrons and nuclei
International Nuclear Information System (INIS)
Close, F.E.
1989-01-01
These lectures discuss the particle-nuclear interface -- a general introduction to the ideas and application of colored quarks in nuclear physics, color, the Pauli principle, and spin flavor correlations -- this lecture shows how the magnetic moments of hadrons relate to the underlying color degree of freedom, and the proton's spin -- a quark model perspective. This lecture reviews recent excitement which has led some to claim that in deep inelastic polarized lepton scattering very little of the spin of a polarized proton is due to its quarks. 38 refs
Factorization and non-factorization in diffractive hard scattering
International Nuclear Information System (INIS)
Berera, Arjun
1997-01-01
Factorization, in the sense defined for inclusive hard scattering, is discussed for diffractive hard scattering. A factorization theorem similar to its inclusive counterpart is presented for diffractive DIS. For hadron-hadron diffractive hard scattering, in contrast to its inclusive counterpart, the expected breakdown of factorization is discussed. Cross section estimates are given from a simple field theory model for non-factorizing double-pomeron-exchange (DPE) dijet production with and without account for Sudakov suppression
Single spin asymmetries in semi-inclusive deep inelastic scattering
International Nuclear Information System (INIS)
Mulders, P.J.
1998-01-01
In this talk I want to illustrate the many possibilities for studying the structure of hadrons in hard scattering processes by giving a number of examples involving increasing complexity in the demands for particle polarization, particle identification or polarimetry. In particular the single spin asymmetries will be discussed. The measurements discussed in this talk are restricted to lepton-hadron scattering, but can be found in various other hard processes such as Drell-Yan scattering or e + e - annihilation. (author)
Hadronic production of high p$_{T}$ leptons and hadrons
2002-01-01
This experiment measures the production of direct real photons with large transverse momentum in pion-nucleon collisions at the SPS (H8 beam) using the NA3 spectrometer with an upgraded e-$\\gamma$ calorimeter. The experiment proceeds in steps of increasing complexity: \\item a) measurement of the direct $\\gamma$ cross-section in $\\pi^{\\pm}$C $\\rightarrow \\gamma +$ X and search for the annihilation process $q\\bar{q} \\rightarrow \\gamma$g by measuring the charge asymmetry at 200 GeV/c; \\item b) determination of the gluon structure function of the pion and the nucleon; \\item c) use of the $\\pi^{-}-\\pi^{+}$ difference on carbon, if found experimentally, to extract the gluon fragmentation from the $\\gamma$ hadron correlations. \\end{enumerate}\\\\ \\\\ For comparison, the quark fragmentation functions can, in principle, be extracted from processes where the Compton scattering qg $\\rightarrow$ q$\\gamma$ dominates and compared with data from D.I.S. as a test of the method. \\\\ \\\\ The existing standard NA3 spectrometer is we...
Possible manifestation of long range forces in high energy hadron collisions
International Nuclear Information System (INIS)
Kuraev, Eh.A.; Ferro, P.; Trentadue, L.
1997-01-01
Pion-pion and photon-photon scattering are discussed.. We obtain, starting from the impact representation introduced by Cheng and Wu a new contribution to the high energy hadron-hadron scattering amplitude for small transferred momentum q 2 of the form is (q 2 /m 4 )ln(-q 2 /m 2 ). This behaviour may be interpreted as a manifestation of long transverse-range forces between hadrons which, for ρ>> m -1 fall off as ρ -4 . We consider the examples of pion and photon scattering with photons converted in the intermediate state to two pairs of quarks interacting by exchanging two gluon colorless state. A phenomenological approach for proton impact factor is used to analyze proton-proton scattering. The analysis of the lowest order radiative corrections for the case of photon-photon scattering is done. We discuss the possibility of observing the effects of these long range forces
Controlling light by light with an optical event horizon.
Demircan, A; Amiranashvili, Sh; Steinmeyer, G
2011-04-22
A novel concept for an all-optical transistor is proposed and verified numerically. This concept relies on cross-phase modulation between a signal and a control pulse. Other than previous approaches, the interaction length is extended by temporally locking control and the signal pulse in an optical event horizon, enabling continuous modification of the central wavelength, energy, and duration of a signal pulse by an up to sevenfold weaker control pulse. Moreover, if the signal pulse is a soliton it may maintain its solitonic properties during the switching process. The proposed all-optical switching concept fulfills all criteria for a useful optical transistor in [Nat. Photon. 4, 3 (2010)], in particular, fan-out and cascadability, which have previously proven as the most difficult to meet.
Hadronic wave functions and high momentum transfer interactions in quantum chromodynamics
International Nuclear Information System (INIS)
Brodsky, S.J.; Huang, T.; Lepage, G.P.
1983-01-01
This chapter emphasizes the utility of a Fock state representation of the meson and baryon wave functions as a means not only to parametrize the effects of bound state dynamics in QCD phenomena, but also to interrelate exclusive, inclusive, and higher twist processes. Discusses hadronic wave functions in QCD, measures of hadronic wave functions (form factors of composite systems, form factors of mesons, the meson distribution amplitude); large momentum transfer exclusive processes (two-photon processes); deep inelastic lepton scattering; and the phenomenology of hadronic wave functions (measures of hadron wave functions, constraints on the pion and proton valence wave function, quark jet diffraction excitation, the ''unveiling'' of the hadronic wave function and intrinsic charm). Finds that the testing ground of perturbative QCD where rigorous, definitive tests of the theory can be made can now be extended throughout a large domain of large momentum transfer exclusive and inclusive lepton, photon, and hadron reactions
Time evolution of hadronization and grey tracks in DIS off nuclei
International Nuclear Information System (INIS)
Ciofi degli Atti, C.; Kopeliovich, B.Z.
2005-01-01
The analysis of the grey tracks produced in deep inelastic scattering (DIS) off nuclei provides important information on the space-time development of hadronization in nuclear medium. This method is complementary to the measurement of nuclear attenuation of leading inclusive hadrons. While the latter is focused on the hadronization dynamics for the quite rare process of leading hadrons production, the former covers the main bulk of inelastic events, and its Q 2 dependence is a very sensitive tool to discriminate between different models of hadronization. Employing the model of perturbative hadronization developed earlier, we calculate the Q 2 and x Bj dependences of the number of collisions and relate it to the mean number of grey tracks, using an empirical relation obtained from the analysis of data from the Fermilab E665 experiment on DIS of muons off the Xe nucleus. We found the number of grey tracks to rise steeply with Q 2 in good agreement with the experimental data
Particles as S-matrix poles: hadron democracy
International Nuclear Information System (INIS)
Chew, G.F.
1989-01-01
The connection between two theoretical ideas of the 1950s is traced in this article, namely that hadrons are nonfundamental, ''composite'' particles and that all physically observable particles correspond to singularities of an analytic scattering matrix. The S matrix theory developed by Werner Heisenberg in the early forties now incorporated the concepts of unitarity, invariance, analyticity and causality. The meson-exchange force meant that poles must be present in nucleon-nuclear and pion-nucleon scattering as predicted by dispersion relations. Experimental work in accessible regions determined pole residues. Pole residue became associated with force strength and pole position with particle mass. In 1959, the author discovered the so-called ''bootstrap'' theory the rho meson as a force generates a rho particle. By the end of the 1950s it was clear that all hadrons had equal status, each being bound states of other hadrons, sustained by hadron exchange forces and that hadrons are self-generated by an S-matrix bootstrap mechanism that determines all their properties. (UK)
Lavender, Gemma
2018-01-01
What is the universe made of? How did it start? This Manual tells the story of how physicists are seeking answers to these questions using the worlds largest particle smasher the Large Hadron Collider at the CERN laboratory on the Franco-Swiss border. Beginning with the first tentative steps taken to build the machine, the digestible text, supported by color photographs of the hardware involved, along with annotated schematic diagrams of the physics experiments, covers the particle accelerators greatest discoveries from both the perspective of the writer and the scientists who work there. The Large Hadron Collider Manual is a full, comprehensive guide to the most famous, record-breaking physics experiment in the world, which continues to capture the public imagination as it provides new insight into the fundamental laws of nature.
International Nuclear Information System (INIS)
Yamazaki, Toshimitsu
1990-01-01
The Japanese Hadron Project (JHP) is aimed at producing various kinds of unstable secondary beams based on high-intensity protons from a new accelerator complex. The 1 GeV protons, first produced from a 1 GeV linac, are transferred to a compressor/stretcher ring, where a sharply-pulsed beam or a stretched continuous beam will be produced. The pulsed beam will be used for a pulsed muon source (M arena) and a spallation neutron source (N arena). A part of the proton beam will be used to produce unstable nuclei, which will be accelerated to several MeV/nucleon (E arena). The purpose and impact of JHP will be described in view of future applications of hadronic beams to nuclear energy and material science. (author)
International Nuclear Information System (INIS)
Roser, T.
1994-01-01
There were four sessions on Hadron Beams and Accelerators with 7 talks on Siberian Snakes and spin rotators, 3 talks on polarization build-up of unpolarized beams in storage rings and 5. 9, and 3 talks on low, medium, and high energy polarimeters, respectively. In this paper I will briefly describe a few highlights from these sessions, giving emphasis to topics which I think will play an important role in the future
International Nuclear Information System (INIS)
Roser, T.
1995-01-01
There were four sessions on Hadron Beams and Accelerators with 7 talks on Siberian Snakes and spin rotators, 3 talks on polarization build-up of unpolarized beams in storage rings and 5, 9, and 3 talks on low, medium, and high energy polarimeters, respectively. In this paper I will briefly describe a few highlights from these sessions, giving emphasis to topics which I think will play an important role in the future. copyright 1995 American Institute of Physics
Juettner Fernandes, Bonnie
2014-01-01
What really happened during the Big Bang? Why did matter form? Why do particles have mass? To answer these questions, scientists and engineers have worked together to build the largest and most powerful particle accelerator in the world: the Large Hadron Collider. Includes glossary, websites, and bibliography for further reading. Perfect for STEM connections. Aligns to the Common Core State Standards for Language Arts. Teachers' Notes available online.
International Nuclear Information System (INIS)
Krivoruchenko, M.I.
1985-01-01
In chiral bag model an expression is obtained for the quark wave functions with account of color and pion interaction of quarks. The quadrupole moments of nonstrange hadrons are calculated. Quadrupole moment of nucleon isobar is found to be Q(Δ)=-6.3x10 -28 esub(Δ)(cm)sup(2). Fredictions of the chiral bag model are in strong disagreement with the non-relativistic quark model
Electromagnetic polarizabilities of hadrons
International Nuclear Information System (INIS)
Friar, J.L.
1988-01-01
Electromagnetic polarizabilities of hadrons are reviewed, after a discussion of classical analogues. Differences between relativistic and non-relativistic approaches can lead to conflicts with conventional nuclear physics sum rules and calculational techniques. The nucleon polarizabilities are discussed in the context of the non-relativistic valence quark model, which provides a good qualitative description. The recently measured pion polarizabilities are discussed in the context of chiral symmetry and quark-loop models. 58 refs., 5 figs
Energy Technology Data Exchange (ETDEWEB)
Brodsky, Stanley J.; Deshpande, Abhay L.; Gao, Haiyan; McKeown, Robert D.; Meyer, Curtis A.; Meziani, Zein-Eddine; Milner, Richard G.; Qiu, Jianwei; Richards, David G.; Roberts, Craig D.
2015-02-26
This White Paper presents the recommendations and scientific conclusions from the Town Meeting on QCD and Hadronic Physics that took place in the period 13-15 September 2014 at Temple University as part of the NSAC 2014 Long Range Planning process. The meeting was held in coordination with the Town Meeting on Phases of QCD and included a full day of joint plenary sessions of the two meetings. The goals of the meeting were to report and highlight progress in hadron physics in the seven years since the 2007 Long Range Plan (LRP07), and present a vision for the future by identifying the key questions and plausible paths to solutions which should define the next decade. The introductory summary details the recommendations and their supporting rationales, as determined at the Town Meeting on QCD and Hadron Physics, and the endorsements that were voted upon. The larger document is organized as follows. Section 2 highlights major progress since the 2007 LRP. It is followed, in Section 3, by a brief overview of the physics program planned for the immediate future. Finally, Section 4 provides an overview of the physics motivations and goals associated with the next QCD frontier: the Electron-Ion-Collider.
Keil, Eberhard
1998-01-01
Plans for future hadron colliders are presented, and accelerator physics and engineering aspects common to these machines are discussed. The Tevatron is presented first, starting with a summary of the achievements in Run IB which finished in 1995, followed by performance predictions for Run II which will start in 1999, and the TeV33 project, aiming for a peak luminosity $L ~ 1 (nbs)^-1$. The next machine is the Large Hadron Collider LHC at CERN, planned to come into operation in 2005. The last set of machines are Very Large Hadron Colliders which might be constructed after the LHC. Three variants are presented: Two machines with a beam energy of 50 TeV, and dipole fields of 1.8 and 12.6 T in the arcs, and a machine with 100 TeV and 12 T. The discussion of accelerator physics aspects includes the beam-beam effect, bunch spacing and parasitic collisions, and the crossing angle. The discussion of the engineering aspects covers synchrotron radiation and stored energy in the beams, the power in the debris of the p...
Hadronization, spin and lifetimes
International Nuclear Information System (INIS)
Grossman, Yuval; Nachshon, Itay
2008-01-01
Measurements of lifetimes can be done in two ways. For very short lived particles, the width can be measured. For long lived ones, the lifetime can be directly measured, for example, using a displaced vertex. Practically, the lifetime cannot be extracted for particles with intermediate lifetimes. We show that for such cases information about the lifetime can be extracted for heavy colored particles that can be produced with known polarization. For example, a t-like particle with intermediate lifetime hadronizes into a superposition of the lowest two hadronic states, T* and T (the equivalent of B* and B). Depolarization effects are governed by time scales that are much longer than the hadronization time scale, Λ QCD -1 . After a time of order 1/Δm, with Δm≡m(T*)-m(T), half of the initial polarization is lost. The polarization is totally lost after a time of order 1/Γ γ , with Γ γ = Γ(T* → Tγ). Thus, by comparing the initial and final polarization, we get information on the particle's lifetime.
Supersymmetry at hadron supercolliders
International Nuclear Information System (INIS)
Dzialo, D.L.
1989-01-01
At the next generation of hadron supercolliders, the proposed US Superconducting Supercollider (SSC) and the European Large Hadron Collider (LHC), protons will be collided at such high energy to allow the creation of new particles with masses greater those that have been previously created in the laboratory. One of the most important questions to be resolved at these accelerators is whether or not any supersymmetric extension of the Standard Model is manifest below the TeV scale. It is expected that the strongly-interacting supersymmetric particles, the gluinos and squarks, will be pair-produced in the most abundance there. Light gluinos primarily decay into quarks and the lightest supersymmetric particle, which is assumed to escape detection; this gives the classic supersymmetric signature of events with large missing momentum. It is known, however, that for gluinos of masses larger than just 100 GeV this process is no longer the preferred gluino decay channel. New signals must therefore be sought to either detect these particles, or to set meaningful lower mass limits. It is in this work that such new detection strategies for supersymmetry at hadron supercolliders are proposed. Gluino and squark production rates and decay channels are studied in a model-independent fashion over the entire theoretical mass range of interest. New experimental signatures are proposed and compared with sources of background over a wide region of the parameter space that characterizes different supersymmetric models
Non-perturbative inputs for gluon distributions in the hadrons
Energy Technology Data Exchange (ETDEWEB)
Ermolaev, B.I. [Ioffe Physico-Technical Institute, Saint Petersburg (Russian Federation); Troyan, S.I. [St. Petersburg Institute of Nuclear Physics, Gatchina (Russian Federation)
2017-03-15
Description of hadronic reactions at high energies is conventionally done in the framework of QCD factorization. All factorization convolutions comprise non-perturbative inputs mimicking non-perturbative contributions and perturbative evolution of those inputs. We construct inputs for the gluon-hadron scattering amplitudes in the forward kinematics and, using the optical theorem, convert them into inputs for gluon distributions in the hadrons, embracing the cases of polarized and unpolarized hadrons. In the first place, we formulate mathematical criteria which any model for the inputs should obey and then suggest a model satisfying those criteria. This model is based on a simple reasoning: after emitting an active parton off the hadron, the remaining set of spectators becomes unstable and therefore it can be described through factors of the resonance type, so we call it the resonance model. We use it to obtain non-perturbative inputs for gluon distributions in unpolarized and polarized hadrons for all available types of QCD factorization: basic, K{sub T}-and collinear factorizations. (orig.)
Non-perturbative inputs for gluon distributions in the hadrons
International Nuclear Information System (INIS)
Ermolaev, B.I.; Troyan, S.I.
2017-01-01
Description of hadronic reactions at high energies is conventionally done in the framework of QCD factorization. All factorization convolutions comprise non-perturbative inputs mimicking non-perturbative contributions and perturbative evolution of those inputs. We construct inputs for the gluon-hadron scattering amplitudes in the forward kinematics and, using the optical theorem, convert them into inputs for gluon distributions in the hadrons, embracing the cases of polarized and unpolarized hadrons. In the first place, we formulate mathematical criteria which any model for the inputs should obey and then suggest a model satisfying those criteria. This model is based on a simple reasoning: after emitting an active parton off the hadron, the remaining set of spectators becomes unstable and therefore it can be described through factors of the resonance type, so we call it the resonance model. We use it to obtain non-perturbative inputs for gluon distributions in unpolarized and polarized hadrons for all available types of QCD factorization: basic, K_T-and collinear factorizations. (orig.)
Intermediate energy semileptonic probes of the hadronic neutral current
International Nuclear Information System (INIS)
Musolf, M.J.; Donnelly, T.W.; Dubach, J.; Beise, E.J.; Maryland Univ., College Park, MD
1993-06-01
The present status and future prospects of intermediate-energy semileptonic neutral current studies are reviewed. Possibilities for using parity-violating electron scattering from nucleons and nuclei to study hadron structure and nuclear dynamics are emphasized, with particular attention paid to probes of strangeness content in the nucleon. Connections are drawn between such studies and tests of the electroweak gauge theory using electron or neutrino scattering. Outstanding theoretical issues in the interpretation of semileptonic neutral current measurements are highlighted and the prospects for undertaking parity-violating electron or neutrino scattering experiments in the near future are surveyed
The role of hadron resonances in hot hadronic matter
Energy Technology Data Exchange (ETDEWEB)
Goity, Jose [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Hampton Univ., Hampton, VA (United States)
2017-02-01
Hadron resonances can play a significant role in hot hadronic matter. Of particular interest for this workshop are the contributions of hyperon resonances. The question about how to quantify the effects of resonances is here addressed. In the framework of the hadron resonance gas, the chemically equilibrated case, relevant in the context of lattice QCD calculations, and the chemically frozen case relevant in heavy ion collisions are discussed.
Hadron muoproduction at the COMPASS experiment
International Nuclear Information System (INIS)
Rajotte, Jean-Francois
2010-01-01
The COMPASS Collaboration has two main fields of interest: to improve our knowledge of the nucleon spin structure and to study hadrons through spectroscopy. These goals require a multipurpose universal spectrometer such as the COmmon Muon and Proton Apparatus for Structure and Spectroscopy, COMPASS. In its first years of data taking (2002-2007), the nucleon spin structure was studied with a polarized muon beam scattering off a polarized target. These studies resumed in 2010 and will continue until at least 2011. The years 2008 and 2009 were dedicated to hadron spectroscopy using hadron beams. In the case of the nucleon structure studies, it is crucial to detect with high precision the incoming beam muon (160 GeV), the scattered muon and the produced hadrons. The large amount of high quality data accumulated provides access to the unpolarized and polarized parton distributions of the nucleon and the hadronization process. Subtle differences (asymmetries) between polarized cross sections have been predicted for hadron production from polarized muon-nucleon interaction for COMPASS. It is based on these differences that the polarized parton distributions can be measured. In this context, it is important to first compare predictions with the gross features of the measured unpolarized semi-inclusive differential cross sections or the closely related differential multiplicities. In order to determine cross sections, the data has to be corrected for the acceptance of the spectrometer. In this thesis, a multidimensional acceptance correction method, based on Monte Carlo simulation, is developed and applied to the data measured in 2004. The method is first used to determine the inclusive muon-nucleon cross section which is compared with a global fit to world data. This serves as a test of the acceptance correction method and to verify if the results from previous experiments can be reproduced. Then, unpolarized differential multiplicities as a function of transverse momentum
Hadron muoproduction at the COMPASS experiment
Energy Technology Data Exchange (ETDEWEB)
Rajotte, Jean-Francois
2010-09-30
The COMPASS Collaboration has two main fields of interest: to improve our knowledge of the nucleon spin structure and to study hadrons through spectroscopy. These goals require a multipurpose universal spectrometer such as the COmmon Muon and Proton Apparatus for Structure and Spectroscopy, COMPASS. In its first years of data taking (2002-2007), the nucleon spin structure was studied with a polarized muon beam scattering off a polarized target. These studies resumed in 2010 and will continue until at least 2011. The years 2008 and 2009 were dedicated to hadron spectroscopy using hadron beams. In the case of the nucleon structure studies, it is crucial to detect with high precision the incoming beam muon (160 GeV), the scattered muon and the produced hadrons. The large amount of high quality data accumulated provides access to the unpolarized and polarized parton distributions of the nucleon and the hadronization process. Subtle differences (asymmetries) between polarized cross sections have been predicted for hadron production from polarized muon-nucleon interaction for COMPASS. It is based on these differences that the polarized parton distributions can be measured. In this context, it is important to first compare predictions with the gross features of the measured unpolarized semi-inclusive differential cross sections or the closely related differential multiplicities. In order to determine cross sections, the data has to be corrected for the acceptance of the spectrometer. In this thesis, a multidimensional acceptance correction method, based on Monte Carlo simulation, is developed and applied to the data measured in 2004. The method is first used to determine the inclusive muon-nucleon cross section which is compared with a global fit to world data. This serves as a test of the acceptance correction method and to verify if the results from previous experiments can be reproduced. Then, unpolarized differential multiplicities as a function of transverse momentum
Scattering Amplitudes via Algebraic Geometry Methods
DEFF Research Database (Denmark)
Søgaard, Mads
Feynman diagrams. The study of multiloop scattering amplitudes is crucial for the new era of precision phenomenology at the Large Hadron Collider (LHC) at CERN. Loop-level scattering amplitudes can be reduced to a basis of linearly independent integrals whose coefficients are extracted from generalized...
Measurement of the contribution of neutrons to hadron calorimeter signals
International Nuclear Information System (INIS)
Akchurin, N.; Berntzon, L.; Cardini, A.; Ferrari, R.; Gaudio, G.; Hauptman, J.; Kim, H.; La Rotonda, L.; Livan, M.; Meoni, E.; Paar, H.; Penzo, A.; Pinci, D.; Policicchio, A.; Popescu, S.; Susinno, G.; Roh, Y.; Vandelli, W.; Wigmans, R.
2007-01-01
The contributions of neutrons to hadronic signals from the DREAM calorimeter are measured by analyzing the time structure of these signals. The neutrons, which mainly originate from the evaporation stage of nuclear breakup in the hadronic shower development process, contribute through elastic scattering off protons in the plastic scintillating fibers which provide the dE/dx information in this calorimeter. This contribution is characterized by an exponential tail in the pulse shape, with a time constant of ∼25ns. The relative contribution of neutrons to the signals increases with the distance from the shower axis. As expected, the neutrons do not contribute to the DREAM Cherenkov signals
Diffractive dissociation of top hadrons at collider energies
International Nuclear Information System (INIS)
Di Bitonto, D.
1983-01-01
In an optical model in which heavy-flavour production is described as coherent scattering within the nucleon, the total heavy-flavour cross-section is expected to obey a m q -2 dependence, while the partial differential cross-section dσ/dp T for top hadrons is expected to show a broad plateau above approx. 20 GeV/c in transverse momentum. The expected top hadron signal dσ/dp T is 60 nb for m t = 20 GeV/c 2 appearing in the approx. angular range of expected value of θ 10 deg - 20 deg. (author)
PREFACE: Focus section on Hadronic Physics
Roberts, Craig; Swanson, Eric
2007-07-01
illustrates how the structure of the nucleon is revealed. Reimer reviews how the Drell--Yan process can be used to explore the sea quark structure of nucleons, thereby probing such phenomena as flavour asymmetry in the nucleon and nuclear medium modification of nucleon properties. The exploitation of the B factories has led to a resurgence of interest in heavy quark spectroscopy. Concurrently, interest in light quark spectroscopy and gluonic excitations remains high, with several new experimental efforts in the planning or building stages. The current status of all of this is reviewed by Rosner. Finally, Vogelsang summarizes the status of polarized deep inelastic lepton-nucleon scattering experiments at RHIC and their impact on the theoretical understanding of nucleon helicity structure, gluon polarization in the nucleus, and transverse spin asymmetries. Of course, hadronic physics is a much broader subject than can be conveyed in this special focus section; advances in effective field theory, lattice gauge theory, generalised parton distributions and many other subfields are not covered here. Nevertheless, we hope that this focus section will help the reader appreciate the vitality, breadth of endeavour, and the phenomenological richness of hadronic physics.
Hadron collider physics at UCR
International Nuclear Information System (INIS)
Kernan, A.; Shen, B.C.
1997-01-01
This paper describes the research work in high energy physics by the group at the University of California, Riverside. Work has been divided between hadron collider physics and e + -e - collider physics, and theoretical work. The hadron effort has been heavily involved in the startup activities of the D-Zero detector, commissioning and ongoing redesign. The lepton collider work has included work on TPC/2γ at PEP and the OPAL detector at LEP, as well as efforts on hadron machines
Energy Technology Data Exchange (ETDEWEB)
Anon.
1979-04-15
Ever since the discovery of charmed mesons in electron-positron annihilations at SLAC and DESY, a considerable effort has gone into looking for them in other types of reactions. Both neutrino interactions and photoproduction have provided further data on the production and decay of D mesons, but little has emerged concerning purely hadronic studies.some results from a CERN/Collège de France/Heidelberg/Karlsruhe collaboration using the Split Field Magnet at the CERN Intersecting Storage Rings (ISR) now show definite signs of D meson production in proton-proton collisions.
International Nuclear Information System (INIS)
Faccini, R.
2010-01-01
In the past few years the field of hadron spectroscopy has seen renewed interest due to the publication, initially mostly from B-Factories, of evidences of states that do not match regular spectroscopy, but are rather candidates for bound states with additional quarks or gluons (four quarks for tetraquarks and molecules and two quarks and gluons for hybrids). A huge effort in understanding the nature of this new states and in building a new spectroscopy is ongoing. This paper reviews the experimental and theoretical state of the art on heavy quarkonium exotic spectroscopy, with particular attention on the steps towards a global picture.
International Nuclear Information System (INIS)
Ferreira, P.L.
1984-01-01
An overview of the current phenomenological models of hadron structure, whose theoretical basis is the Quantum Chromodynamics (QCD), is presented. A short introduction to the QCD permits to focalize the relevant properties which are attached to those models. Following, bag-like models (in particular, MIT bag and chiral extensions) and potential-like models among them the Karl and Isgur non-relativistic model and a semi-relativistic model, free of the Klein paradox, with equal scalar-vetorial mixture of confinement potential are shortly studied. Enphasis is given to the baryons, treated, basically, as three-quarks systems. (L.C.) [pt
International Nuclear Information System (INIS)
Cohen-Tannoudji, G.
1989-01-01
This series of lectures is devoted to review ot he connections between QCD and string theories. One reviews the phenomenological models leading to string pictures in non perturbative QCD and the string effects, related to soft gluon coherence, which arise in perturbative QCD. One tries to build a string theory which goes to QCD at the zero slope limit. A specific model, based on superstring theories is shown to agree with QCD four point amplitudes at the Born approximation and with one loop corrections. One shows how this approach can provide a theoretical framework to account for the phenomenological property of parton-hadron duality.(author)
Directory of Open Access Journals (Sweden)
Wada Masayuki
2012-11-01
Full Text Available The results of resonance particle productions (ρ0, ω, K*, ϕ, Σ*, and Λ* measured by the STAR collaboration at RHIC from various colliding systems and energies are presented. Measured mass, width, 〈pT〉, and yield of those resonances are reviewed. No significant mass shifts or width broadening beyond the experiment uncertainties are observed. New measurements of ϕ and ω from leptonic decay channels are presented. The yields from leptonic decay channels are compared with the measurements from hadronic decay channels and the two results are consistent with each other.
Deeply Virtual Neutrino Scattering
International Nuclear Information System (INIS)
Ales Psaker
2007-01-01
We investigate the extension of the deeply virtual Compton scattering process into the weak interaction sector. Standard electromagnetic Compton scattering provides a unique tool for studying hadrons, which is one of the most fascinating frontiers of modern science. In this process the relevant Compton scattering amplitude probes the hadron structure by means of two quark electromagnetic currents. We argue that replacing one of the currents with the weak interaction current can promise a new insight. The paper is organized as follows. In Sec. II we briefly discuss the features of the handbag factorization scheme. We introduce a new set of phenomenological functions, known as generalized parton distributions (GPDs) [1-6], and discuss some of their basic properties in Sec. III. An application of the GPD formalism to the neutrino-induced deeply virtual Compton scattering in the kinematics relevant to future high-intensity neutrino experiments is given in Sec. IV. The cross section results are presented in Sec. V. Finally, in Sec. VI we draw some conclusions and discuss future prospects. Some of the formal results in this paper have appeared in preliminary reports in Refs. [7] and [8], whereas a comprehensive analysis of the weak neutral and weak charged current DVCS reactions in collaboration with W. Melnitchouk and A. Radyushkin has been presented in Ref. [9
What (if anything) can few-body strange systems teach us about quark-gluon hadronic substructure?
International Nuclear Information System (INIS)
Maltman, K.
1990-01-01
We discuss expectation, relevant to the proposed (π,K) program at PILAC, for the effects of hadronic quark-gluon substructure on the physics of few-body strangeness -1 systems, in the context of QCD-inspired models used previously to describe the hadron spectrum and short distance nucleon-nucleon scattering. 50 refs., 2 tabs
Hadron production near threshold
Indian Academy of Sciences (India)
Abstract. Final state interaction effects in pp → pΛK+ and pd → 3He η reactions are explored near threshold to study the sensitivity of the cross-sections to the pΛ potential and the ηN scattering matrix. The final state scattering wave functions between Λ and p and η and 3He are described rigorously. The Λ production is ...
High-energy hadron-hadron collisions
International Nuclear Information System (INIS)
Yang, C.N.
1983-01-01
While high energy collision experiments yield a wealth of complicated patterns, there are a few general and very striking features that stand out. Because of the universality of these features, and because of the dominating influence they have on high energy phenomena, it is the authors opinion that a physical picture of high energy collisions must address itself first of all to these features before going into specific details. In this short talk these general and striking features are stated and a physical picture developed in the last few years to specifically accommodate these features is described. The picture was originally discussed for elastic scattering. But it leads naturally, indeed inevitably as they shall discuss, to conclusions about inelastic processes, resulting in an idea called the hypothesis of limiting fragmentation
Hadronic final state in DIS at low x at HERA
International Nuclear Information System (INIS)
Shekelyan, V.
1996-01-01
Deep-inelastic scattering (γ * p) interactions with photon virtualities Q 2 > 5 GeV 2 and photon-proton (γp) interactions with Q 2 -2 GeV 2 are studied at the high energy electron-proton collider HERA. The transverse energy flow and relative rates of large rapidity gap events are compared in the two event samples. The observed similarity between γ * p and γp interactions can be understood in a picture where the photon develops as a hadronic object. The transverse energy density measured in the central region of the collision, at η * = 0 in the γ * p centre of mass frame, is compared with data from hadron-hadron interactions as function of the CMS energy of the collision. (author)
Confinement and hadron-hadron interactions by general relativistic methods
Recami, Erasmo
By postulating covariance of physical laws under global dilations, one can describe gravitational and strong interactions in a unified way. Namely, in terms of the new discrete dilational degree of freedom, our cosmos and hadrons can be regarded as finite, similar systems. And a discrete hierarchy of finite ``universes'' may be defined, which are governed by fields with strengths inversally proportional to their radii; in each universe an Equivalence Principle holds, so that the relevant field can be there geometrized. Scaled-down Einstein equations -with cosmological term- are assumed to hold inside hadrons (= strong micro-cosmoses); and they yield in a natural way classical confinement, as well as ``asymptotic freedom'', of the hadron constituents. In other words, the association of strong micro-universes of Friedmann type with hadrons (i.e., applying the methods of General Relativity to subnuclear particle physics) allows avoiding recourse to phenomenological models such as the Bag Model. Inside hadrons we have to deal with a tensorial field (= strong gravity), and hadron constituents are supposed to exchange spin-2 ``gluons''. Our approach allows us also to write down a tensorial, bi-scale field theory of hadron-hadron interactions, based on modified Einstein-type equations here proposed for strong interactions in our space. We obtain in particular: (i) the correct Yukawa behaviour of the strong scalar potential at the static limit and for r>~l fm; (ii) the value of hadron radii. As a byproduct, we derive a whole ``numerology'', connecting our gravitational cosmos with the strong micro-cosmoses (hadrons), such that it does imply no variation of G with the epoch. Finally, since a structute of the ``micro-universe'' type seems to be characteristic even of leptons, a hope for the future is including also weak interactions in our classical unification of the fundamental forces.
International Nuclear Information System (INIS)
Olsen, S.L.
2014-01-01
QCD-motivated models for hadrons predict an assortment of "exotic" hadrons that have structures that are more complex than the quark-antiquark mesons and three-quark baryons of the original quark-parton model. These include pentaquark baryons, the six-quark H-dibaryon, and tetraquark and glueball mesons. Despite extensive experimental searches, no unambiguous candidates for any of these exotic configurations have yet to be identified. On the other hand, a number of meson states, one that seems to be a proton-antiproton bound state, and others that contain either charmed-anticharmed quark pairs or bottom-antibottom quark pairs, have been recently discovered that neither fit into the quark-antiquark meson picture nor match the expected properties of the QCD-inspired exotics. Here I briefly review results from a recent search for the H-dibaryon, and discuss some properties of the newly discovered states –the so-called XYZ mesons– and compare them with expectations for conventional quark-antiquark mesons and the predicted QCD-exotic states. (author)
International Nuclear Information System (INIS)
Cahill, R.T.
1992-01-01
A review is given of progress in deriving the effective action for hadronic physics, S[π, ρ, ω, .., anti N, N, ..], from the fundamental defining action of QCD, S[anti q, q, A μ a ]. This is a problem in quantum field theory and the most success so far has been achieved using functional integral calculus (FIC) techniques. This formulates the problem as an exercise in changing the variables of integration in the functional integrals, from those of the quark and gluon fields to those of the (bare) meson and baryon fields. The appropriate variables are determined by the dynamics of QCD, and the final hadronic variables (essentially the 'normal modes' of QCD) are local fields describing the 'centre-of-mass' motion of extended bound states of quarks. The quarks are extensively dressed by the gluons, and the detailed aspects of the hidden chiral symmetry emerge naturally from the formalism. Particular attention is given to covariant integral equations which determine bare nucleon structure (i.e. in the quenched approximation). These equations, which arise from the closed double-helix diagrams of the FIC analysis, describe the baryons in terms of quark-diquark structure, in the form of Faddeev equations. This hadronisation of QCD also generates the dressing of these baryons by the pions, and the non-local πNN coupling. (orig.)
International Nuclear Information System (INIS)
Dzhelyadin, R.I.
2002-01-01
The Hadron Calorimeter (HCAL) is designed for the LHCb experiment. The main purpose of the detector is to provide data for the L0 hadron trigger. The HCAL is designed as consisting of two symmetric movable parts of about 500 ton in total getting in touch in operation position without non-instrumented zones. The lateral dimensions of an active area are X=8.4 m width, Y=6.8 m height, and is distanced from the interaction point at Z=13.33 m. Both halves are assembled from stacked up modules. An internal structure consisting of thin iron plates interspaced with scintillating tiles has been chosen. Attention is paid to optimize the detector according to the requirements of the experiment, reducing the spending needed for its construction. Different construction technologies are being discussed. The calorimeter properties have been extensively studied with a variety of prototype on the accelerator beam. The calibration with a radioactive source and module-0 construction experience is discussed
Study of quantum hadronic states using new optimum principles and new coherent production mechanisms
International Nuclear Information System (INIS)
Ion, D. B.; Ion, M. L.; Ion-Mihai, R.
2002-01-01
We introduced a new kind of quantum entropy for quantum scattering: conjugated nonextensivity entropy S Jθ bar (p,q). Using this new kind of nonextensive entropy we studied the nonextensive quantum scattering states of the hadronic interactions. We proved that probability distributions produced at quantum equilibrium coincide with optimal distributions given by the principle of minimum distance in the space of quantum scattering states. Using optimal states we proved new uncertainty relations and new entropic bands: For experimental tests we used the available phase shifts for the pion-nucleus scatterings and also for the pion-nucleon scatterings. Experimental tests of entropic bands and principle of maximum entropy for conjugated nonextensivity entropy are compared with entropic bands for usual entropy of joint probability S Jθ bar (p) and for pion-nucleus scatterings. Also given are the experimental tests of entropic bands and principle of maximum entropy for conjugated nonextensivity entropy compared with entropic bands for usual entropy of joint probability S Jθ bar (p) and for pion-nucleon scatterings.Our experimental tests proved the existence of the principle of limited entropic uncertainty in hadronic scattering. The experimental tests showed clearly that quantum elastic scattering is well described by the principle of minimum distance in the space of quantum states. By these results we obtained strong evidence for the nonextensivity of the hadronic scattering statistics. (authors)
Exotic hadron and string junction model
International Nuclear Information System (INIS)
Imachi, Masahiro
1978-01-01
Hadron structure is investigated adopting string junction model as a realization of confinement. Besides exotic hadrons (M 4 , B 5 etc.), unconventional hadrons appear. A mass formula for these hadrons is proposed. New selection rule is introduced which requires the covalence of constituent line at hadron vertex. New duality appears due to the freedom of junction, especially in anti BB→anti BB reaction. A possible assignment of exotic and unconventional hadrons to recently observed narrow meson states is presented. (auth.)
Energy Technology Data Exchange (ETDEWEB)
Marquet, C
2006-09-15
When probing small distances inside a hadron, one can resolve its partonic constituents: quarks and gluons that obey the laws of perturbative Quantum Chromodynamics (QCD). This substructure reveals itself in hadronic collisions characterized by a large momentum transfer: in such collisions, a hadron acts like a collection of partons whose interactions can be described in QCD. In a collision at moderate energy, a hadron looks dilute and the partons interact incoherently. As the collision energy increases, the parton density inside the hadron grows. Eventually, at some energy much bigger than the momentum transfer, one enters the saturation regime of QCD: the gluon density has become so large that collective effects are important. We introduce a formalism suitable to study hadronic collisions in the high-energy limit in QCD, and the transition to the saturation regime. In this framework, we derive known results that are needed to present our personal contributions and we compute different cross-sections in the context of hard diffraction and particle production. We study the transition to the saturation regime as given by the Balitsky-Kovchegov equation. In particular we derive properties of its solutions.We apply our results to deep inelastic scattering and show that, in the energy range of the HERA collider, the predictions of high-energy QCD are in good agreement with the data. We also consider jet production in hadronic collisions and discuss the possibility to test saturation at the Large Hadron Collider. (author)
Hadron Correlations and Parton Recombination
Energy Technology Data Exchange (ETDEWEB)
Fries, R.J. [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)]. E-mail: rjfries@comp.tamu.edu
2007-02-15
Parton recombination has been found to be an extremely useful model to understand hadron production at the Relativistic Heavy Ion Collider. It is particularly important to explore its connections with hard processes. This article reviews some of the aspects of the quark recombination model and places particular emphasis on hadron correlations.
Quarkonium production in hadronic collisions
International Nuclear Information System (INIS)
Gavai, R.; Schuler, G.A.; Sridhar, K.
1995-01-01
We summarize the theoretical description of charmonium and bottonium production in hadronic collisions and compare it to the available data from hadron-nucleon interactions. With the parameters of the theory established by these data, we obtain predictions for quarkonium production at RHIC and LHC energies
Hadron induced leptons and photons
International Nuclear Information System (INIS)
Cronin, J.W.
1977-01-01
A review of direct production of leptons and photons in hadron-hadron collisions is presented. Production of lepton pairs with large mass is well accounted for by the Drell-Yan process. The origin of direct single leptons is principally due to the production of lepton pairs. A dominant source of lepton pairs is at low effective mass, m [de
Current Status of Exotic Hadrons
International Nuclear Information System (INIS)
Saeed, M.A.; Ahmed, Maqsood; Fazal-e-Aleem
2005-01-01
Physics of exotic hadrons is in the limelight these days. The models for these baryons are discussed as well as their production and decay processes and methods of their identification. The results of recent experiments in this field are presented, in which some unusual states are observed. These states are candidates for exotic hadrons
International Nuclear Information System (INIS)
Migdal, A.B.; Khokhlachev, S.B.; Borue, V.Yu.
1989-01-01
The hadron is considered as a stringlike gluon drop with a quark and antiquark near the ends of the 'string' for a meson and with the antiquark replaced by a diquark for a baryon. The softer 'string' modes are the rotations and the longitudinal vibrations. Quantization of these modes enables to describe the hadron spectra. (orig.)
Spin structure of hadronization products
International Nuclear Information System (INIS)
Clavelli, L.
1979-03-01
We point out that the hypothesis of soft hadronization together with Lorentz invariance strongly constrain the hadronization process ine + e - annihilation. A final stage jet hypothesis is made which satisfies these constraints. The resulting picture leads to testable predictions not obtainable from perturbative QCD. (orig.) [de
Hadrons in dense matter. Proceedings
International Nuclear Information System (INIS)
Buballa, M.; Noerenberg, W.; Schaefer, B.J.; Wambach, J.
2000-03-01
The following topics were dealt with: Elementary hadronic reactions, Delta dynamics in nuclei, in-medium s-wave ππ-correlations, strangeness in hot and dense matter, medium modifications of vector mesons and dilepton production, medium modifications of charmonium, thermal properties of hot and dense hadronic matter, nuclear matter, spectral functions and QCD sum rules
Forward diffraction amplitude of pp and pp elastic scattering at accelerator energies
International Nuclear Information System (INIS)
Kawasaki, M.; Maehara, T.; Yonezawa, M.
2004-01-01
A simple relation between the total cross section and the forward exponential slope of the elastic differential cross section of pp and pp scattering is indicated. An interpretation of this relation is presented as the formation of a black-disk structure for the elastic diffraction interaction of hadron-hadron scattering at the nonasymptotic energy region
Dynamical theory of hadrons based upon extended particle picture
International Nuclear Information System (INIS)
Hara, Osamu
1980-01-01
An extended particle model of hadrons is discussed on the basis of the assumption that the hadrons correspond to the respective eigenstates of the internal motion of extended bodies which are considered as deformable spheres for simplicity. Such three-dimensionally extended bodies have several remarkable features. The first point is that it is allowed to make half-integer spin. The internal motion of the bodies can be described in terms of quark-like excitons. But the great difference is that these quark-like excitons obey Bose statistics. Therefore in this model, there is no positive reason to introduce the degree of freedom of color at least from the symmetry reason. The second point is that the triality must be restricted to zero. Therefore, the particles with fractional charge do not appear, and the confinement is automatic. It is assumed that the interaction among hadrons takes place due to the coupling of current carried by excited quark-like excitons. All hadron interactions are described in terms of a single coupling constant characterizing the coupling between current and intermediate field. Once the interaction Hamiltonian is given, it is straight forward to calculate scattering amplitude. High energy charge exchange scattering and the decay width of higher resonances can be understood. (Kako, I.)
Feynman rules of quantum chromodynamics inside a hadron
International Nuclear Information System (INIS)
Lee, T.D.
1979-01-01
We start from quantum chromodynamics in a finite volume of linear size L and examine its color-dielectric constant kappa/sub L/, especially the limit kappa/sub infinity/ as L → infinity. By choosing as our standard kappa/sub L/ = 1 when L = some hadron size R, we conclude that kappa/sub infinity/ must be -2 α where α is the fine-structure constant of QCD inside the hadron. A permanent quark confinement corresponds to the limit kappa/sub infinity/ = 0. The hadrons are viewed as small domain structures (with color-dielectric constant = 1) immersed in a perfect, or nearly perfect, color-dia-electric medium, which is the vacuum. The Feynman rules of QCD inside the hadron are derived; they are found to depend on the color-dielectric constant kappa/sub infinity/ of the vacuum that lies outside. We show that, when kappa/sub infinity/ → 0, the mass of any color-nonsinglet state becomes infinity, but for color-singlet states their masses and scattering amplitudes remain finite. These new Feynman rules also depend on the hadron size R. Only at high energy and large four-momentum transfer can such R dependence be neglected and, for color-singlet states, these new rules be reduced to the usual ones
Hadronic resonance production measured with the ALICE detector
Dash, Ajay
2015-01-01
Hadronic resonances serve as a unique tool to study the properties of hot and dense matter pro- duced in heavy-ion collisions. These properties can be studied by measuring the ratios of hadronic resonance yields to the yields of longer-lived hadrons which can be used to investigate the re- scattering effects and the chemical freeze-out temperature. Resonance measurements in pp and p–Pb collisions provide a necessary baseline for heavy-ion data and help to disentangle the initial- state effects from medium-induced effects. The ALICE Collaboration has measured resonances such as, K ∗ (892) 0 and φ (1020) in pp, p–Pb, and Pb–Pb collisions at the LHC energies. These resonances are reconstructed via their hadronic decay channel in a wide momentum range at midrapidity. In this work, we present recent results on the transverse momentum spectra, mean transverse momentum, ratios of resonance production relative to that of long-lived hadrons.
Scattering processes and resonances from lattice QCD
Briceño, Raúl A.; Dudek, Jozef J.; Young, Ross D.
2018-04-01
The vast majority of hadrons observed in nature are not stable under the strong interaction; rather they are resonances whose existence is deduced from enhancements in the energy dependence of scattering amplitudes. The study of hadron resonances offers a window into the workings of quantum chromodynamics (QCD) in the low-energy nonperturbative region, and in addition many probes of the limits of the electroweak sector of the standard model consider processes which feature hadron resonances. From a theoretical standpoint, this is a challenging field: the same dynamics that binds quarks and gluons into hadron resonances also controls their decay into lighter hadrons, so a complete approach to QCD is required. Presently, lattice QCD is the only available tool that provides the required nonperturbative evaluation of hadron observables. This article reviews progress in the study of few-hadron reactions in which resonances and bound states appear using lattice QCD techniques. The leading approach is described that takes advantage of the periodic finite spatial volume used in lattice QCD calculations to extract scattering amplitudes from the discrete spectrum of QCD eigenstates in a box. An explanation is given of how from explicit lattice QCD calculations one can rigorously garner information about a variety of resonance properties, including their masses, widths, decay couplings, and form factors. The challenges which currently limit the field are discussed along with the steps being taken to resolve them.
Unique Description for Single Transverse Spin Asymmetries in DIS and Hadronic Collisions
International Nuclear Information System (INIS)
Yuan Feng
2007-01-01
We derive a unique formula for the single-transverse-spin asymmetry in semi-inclusive hadron production in deep inelastic scattering, valid for all transverse momentum region. Based on this, we further study the integrated asymmetry weighted with transverse-momentum. They can be evaluated in terms of the twist-three quark-gluon correlation functions, which are responsible for the single spin asymmetry in single inclusive hadron production in hadronic collisions. By using the fitted twist-three functions from the hadronic collision data, we find a consistent description for SSAs in deep inelastic scattering. This demonstrates that we have a unique picture for SSAs in these two processes, and shall provide important guidelines for future studies
A conservation law, entropy principle and quantization of fractal dimensions in hadron interactions
Zborovský, I.
2018-04-01
Fractal self-similarity of hadron interactions demonstrated by the z-scaling of inclusive spectra is studied. The scaling regularity reflects fractal structure of the colliding hadrons (or nuclei) and takes into account general features of fragmentation processes expressed by fractal dimensions. The self-similarity variable z is a function of the momentum fractions x1 and x2 of the colliding objects carried by the interacting hadron constituents and depends on the momentum fractions ya and yb of the scattered and recoil constituents carried by the inclusive particle and its recoil counterpart, respectively. Based on entropy principle, new properties of the z-scaling concept are found. They are conservation of fractal cumulativity in hadron interactions and quantization of fractal dimensions characterizing hadron structure and fragmentation processes at a constituent level.
Photon structure and the production of jets, hadrons, and prompt photons
International Nuclear Information System (INIS)
Klasen, M.
1999-01-01
We give a pedagogical introduction to hard photoproduction processes at HERA, including the production of jets, hadrons, and prompt photons. Recent theoretical developments in the three areas are reviewed. In summary, hard photoproduction processes can provide very useful information on the hadronic structure of the photon, in particular on the gluon density, which is complimentary to the information coming from deep inelastic photon-photon scattering at electron-positron colliders. Among the different hadronic final states, jets are most easily accessible experimentally and phenomenologically. On the other hand, inclusive hadron production offers the possibility to test the universality of hadron fragmentation functions and measure the photon structure down to very low values of p T and x γ . Prompt photon production suffers from a reduced cross section and limited data, but allows for the additional testing of photon fragmentation functions
Hadron structure in a simple model of quark/nuclear matter
International Nuclear Information System (INIS)
Horowitz, C.J.; Moniz, E.J.; Negele, J.W.
1985-01-01
We study a simple model for one-dimensional hadron matter with many of the essential features needed for examining the transition from nuclear to quark matter and the limitations of models based upon hadron rather than quark degrees of freedom. The dynamics are generated entirely by the quark confining force and exchange symmetry. Using Monte Carlo techniques, the ground-state energy, single-quark momentum distribution, and quark correlation function are calculated for uniform matter as a function of density. The quark confinement scale in the medium increases substantially with increasing density. This change is evident in the correlation function and momentum distribution, in qualitative agreement with the changes observed in deep-inelastic lepton scattering. Nevertheless, the ground-state energy is smooth throughout the transition to quark matter and is described remarkably well by an effective hadron theory based on a phenomenological hadron-hadron potential
CMS hadronic forward calorimeter
International Nuclear Information System (INIS)
Merlo, J.P.
1998-01-01
Tests of quartz fiber prototypes, based on the detection of Cherenkov light from showering particles, demonstrate a detector possessing all of the desirable characteristics for a forward calorimeter. A prototype for the CMS experiment consists of 0.3 mm diameter fibers embedded in a copper matrix. The response to high energy (10-375 GeV) electrons, pions, protons and muons, the light yield, energy and position resolutions, and signal uniformity and linearity, are discussed. The signal generation mechanism gives this type of detector unique properties, especially for the detection of hadronic showers: Narrow, shallow shower profiles, hermeticity and extremely fast signals. The implications for measurements in the high-rate, high-radiation LHC environment are discussed. (orig.)
Hadronic collision and hadronic structure (an experimental review)
International Nuclear Information System (INIS)
Davier, M.
1975-01-01
In this set of lectures an attempt is made to present a survey of the available experimental data on hadronic collisions at large transverse momentum, together with their current phenomenological descriptions. In particular, the experimental confirmation of constituent structure is looked at in a critical way. The emphasis throughout is to let the data speak in the most unbiased way and to gather evidence as to the short range structure of the hadronic interactions. Finally the current information on lepton production in hadronic collisions is reviewed
International Nuclear Information System (INIS)
Gunnellini, Paolo
2015-03-01
Measurements of the differential cross sections for multijet scenarios in proton-proton collisions are presented as a function of the transverse momentum p T and pseudorapidity, together with the correlations in azimuthal angle and the p T balance among the jets. Two different scenarios are separately studied; in the first one an exclusive four-jet final state is selected in vertical stroke η vertical stroke <4.7, by requiring two hard jets with p T >50 GeV each, together with two jets of p T >20 GeV each. No other jets with p T >20 GeV are allowed in the selected events. In the second one at least four jets with p T >20 GeV are required: two of the four selected jets are asked to be originated by a b-quark in vertical stroke η vertical stroke <2.4, while no requests on the flavour of the other two jets, which are selected within vertical stroke η vertical stroke <4.7 are applied. The data sample was collected in 2010 at a center-of-mass energy of 7 TeV with the CMS detector at the LHC, with an integrated luminosity of 36 pb -1 . The total cross section is measured to be σ(pp→ 4j+X)=330±5 (stat.)±4(syst.) and σ(pp→2b+2j+X)=67.2±2.2(stat.)±22.5 (syst.) for, respectively, the two selected multijet scenarios. It is found that fixed-order matrix element calculations including parton showers describe the measured differential cross sections in some regions of phase space only, and that adding contributions from double parton scattering brings the Monte Carlo predictions closer to the data. A new method of extraction of double parton scattering contributions from an experimental measurement is introduced for the first time: it is applied to W+dijet measurements and to both multijet channels. Values of σ eff are measured to be 19.0 +4.6 -3.0 mb and 23.2 +3.3 -2.5 mb for the two examined selections. These values are consistent between each other and compatible with measurements based on different physics channels at 7 TeV.
Towards a quantitative description of hadronic weak decays
International Nuclear Information System (INIS)
Bigi, I.I.Y.
1981-01-01
We develop a formalism for describing hadronic weak annihilation decays in analogy to the treatment of deep inelastic lepton-nucleon scattering: we write down evolution equations for colour singlet and octet (Qanti q) systems inside mesons of increasing mass. Using D decays as input we can predict weak annihilation decay rates of heavier mesons in a semiquantitative fashion despite our ignorance on bound-state dynamics. (orig.)
Inelastic electron photon scattering at moderate four momentum transfers
International Nuclear Information System (INIS)
Berger, C.; Genzel, H.; Grigull, R.; Lackas, W.; Raupach, F.; Klovning, A.; Lillestoel, E.; Skard, J.A.; Ackermann, H.; Buerger, J.
1980-10-01
We present new high statistics data on hadron production in photon photon reactions. The data are analyzed in terms of an electron photon scattering formalism. The dependence of the total cross section on Q 2 , the four momentum transfer squared of the scattered electron, and on the mass W of the hadronic system is investigated. The data are compared to predictions from Vector Dominance and the quark model. (orig.)
Deep inelastic scattering in spontaneously broken gauge models
International Nuclear Information System (INIS)
Goloskokov, S.V.; Mikhov, S.G.; Morozov, P.T.; Stamenov, D.B.
1975-01-01
Deep inelastic lepton hadron scattering in the simplest spontaneously broken symmetry (the Kibble model) is analyzed. A hypothesis that the invariant coupling constant of the quartic selfinteraction for large spacelike momenta tends to a finite asymptotic value without spoiling the asymptotic freedom for the invariant coupling constant of the Yang-Mills field is used. It is shown that Biorken scaling for the moments of the structure functions of the deep inelastic lepton hadron scattering is violated by powers of logarithms
About the damping of quark-hadron form factors in relative quark momentum
International Nuclear Information System (INIS)
Lewin, K.; Kallies, W.
1979-01-01
A problem of sufficient damping of hadron bound states at nonasymptotic relative quark momenta is discussed. This phenomenon is considered in the connection with the power scaling beginning at momentum transfer | t | >= 2-3 GeV 2 . Damping of hadron bound states is obtained on the basis of a behaviour of four-quark Green's functions in the momentum transfer which is required by diffraction scattering
Relativistic Few-Body Hadronic Physics Calculations
Energy Technology Data Exchange (ETDEWEB)
Polyzou, Wayne [Univ. of Iowa, Iowa City, IA (United States)
2016-06-20
The goal of this research proposal was to use ``few-body'' methods to understand the structure and reactions of systems of interacting hadrons (neutrons, protons, mesons, quarks) over a broad range of energy scales. Realistic mathematical models of few-hadron systems have the advantage that they are sufficiently simple that they can be solved with mathematically controlled errors. These systems are also simple enough that it is possible to perform complete accurate experimental measurements on these systems. Comparison between theory and experiment puts strong constraints on the structure of the models. Even though these systems are ``simple'', both the experiments and computations push the limits of technology. The important property of ``few-body'' systems is that the ``cluster property'' implies that the interactions that appear in few-body systems are identical to the interactions that appear in complicated many-body systems. Of particular interest are models that correctly describe physics at distance scales that are sensitive to the internal structure of the individual nucleons. The Heisenberg uncertainty principle implies that in order to be sensitive to physics on distance scales that are a fraction of the proton or neutron radius, a relativistic treatment of quantum mechanics is necessary. The research supported by this grant involved 30 years of effort devoted to studying all aspects of interacting two and three-body systems. Realistic interactions were used to compute bound states of two- and three-nucleon, and two- and three-quark systems. Scattering observables for these systems were computed for a broad range of energies - from zero energy scattering to few GeV scattering, where experimental evidence of sub-nucleon degrees of freedom is beginning to appear. Benchmark calculations were produced, which when compared with calculations of other groups provided an essential check on these complicated calculations. In
Hadronic wave functions at short distances and the operator product expansion
International Nuclear Information System (INIS)
Brodsky, S.J.; Lepage, G.P.
1980-01-01
The operator product expansion, of appropriate products of quark fields, is used to find the anamalous dimensions which control the short distance behavior of hadronic wave functions. This vehavior in turn controls the high-Q 2 limit of hadronic form factors. In particular, we relate each anamalous dimension of the nonsinglet structure functions to a corresponding logarithmic correction factor to the nominal αsub(s)(Q 2 )/Q 2 fall off of meson form factors. Unlike the case of deep inelastic lepton-hadron scattering, the operator product necessary here involves extra terms which do not contribute to forward matrix elements. (orig.)
From hadronic parity violation to electron parity-violating experiments
International Nuclear Information System (INIS)
Oers, Willem T.H. van
2010-01-01
The weak interaction is manifested in parity-violating observables. With the weak interaction extremely well known parity-violating measurements in hadronic systems can be used to deduce strong interaction effects in those systems. Parity-violating analyzing powers in electron-proton scattering have led to determining the strange quark contributions to the charge and magnetization distributions of the nucleon. Parity-violating electron-proton and electron-electron scattering can also be performed to test the predictions of the Standard Model in the 'running' of the electroweak mixing angle or sin 2 θ W .
The theory of hadronic systems. Annual progress report
International Nuclear Information System (INIS)
Gibbs, W.R.
1993-01-01
This report briefly discusses progress on the following topics: isospin breaking in the pion-nucleon system; direct capture of pions into deeply bound atomic states; knock out of secondary components in the nucleus; study of the radii of neutron distributions in nuclei; the hadronic double scattering operator; transparency in pion production; asymmetry in pion scattering and charge exchange from polarized nuclei; the mechanism of pion absorption in nuclei; the neutron-proton charge-exchange reaction; modification of the fundamental structure of nucleons in nuclei; and antiproton annihilation in nuclei
Hadron collider physics 2005. Proceedings
International Nuclear Information System (INIS)
Campanelli, M.; Clark, A.; Wu, X.
2006-01-01
The Hadron Collider Physics Symposia (HCP) are a new series of conferences that follow the merger of the Hadron Collider Conferences with the LHC Symposia series, with the goal of maximizing the shared experience of the Tevatron and LHC communities. This book gathers the proceedings of the first symposium, HCP2005, and reviews the state of the art in the key physics directions of experimental hadron collider research: - QCD physics - precision electroweak physics - c-, b-, and t-quark physics - physics beyond the Standard Model - heavy ion physics The present volume will serve as a reference for everyone working in the field of accelerator-based high-energy physics. (orig.)
Heavy quarks in hadronic collisions
International Nuclear Information System (INIS)
Brodsky, S.J.; Peterson, C.
1982-03-01
It is suggested that the presence of c anti c-pairs on the 1 to 2% level in the hadron Fock state decomposition (intrinsic charm) gives a natural description of the ISR data for charm hadron production. The theoretical foundations of the intrinsic charm hypothesis together with its consequences for lepton- and hadron-induced reactions are discussed in some detail. There is no contradiction with the EMC data on F 2 /sup c/ provided the appropriate threshold dependence is taken into account
Physics at Future Hadron Colliders
Baur, U.; Parsons, J.; Albrow, M.; Denisov, D.; Han, T.; Kotwal, A.; Olness, F.; Qian, J.; Belyaev, S.; Bosman, M.; Brooijmans, G.; Gaines, I.; Godfrey, S.; Hansen, J.B.; Hauser, J.; Heintz, U.; Hinchliffe, I.; Kao, C.; Landsberg, G.; Maltoni, F.; Oleari, C.; Pagliarone, C.; Paige, F.; Plehn, T.; Rainwater, D.; Reina, L.; Rizzo, T.; Su, S.; Tait, T.; Wackeroth, D.; Vataga, E.; Zeppenfeld, D.
2001-01-01
We discuss the physics opportunities and detector challenges at future hadron colliders. As guidelines for energies and luminosities we use the proposed luminosity and/or energy upgrade of the LHC (SLHC), and the Fermilab design of a Very Large Hadron Collider (VLHC). We illustrate the physics capabilities of future hadron colliders for a variety of new physics scenarios (supersymmetry, strong electroweak symmetry breaking, new gauge bosons, compositeness and extra dimensions). We also investigate the prospects of doing precision Higgs physics studies at such a machine, and list selected Standard Model physics rates.
Fundamentals in hadronic atom theory
Deloff, A
2003-01-01
Hadronic atoms provide a unique laboratory for studying hadronic interactions essentially at threshold. This text is the first book-form exposition of hadronic atom theory with emphasis on recent developments, both theoretical and experimental. Since the underlying Hamiltonian is a non-self-adjoined operator, the theory goes beyond traditional quantum mechanics and this book covers topics that are often glossed over in standard texts on nuclear physics. The material contained here is intended for the advanced student and researcher in nuclear, atomic or elementary-particle physics. A good know
Hadron collider physics at UCR
Energy Technology Data Exchange (ETDEWEB)
Kernan, A.; Shen, B.C.
1997-07-01
This paper describes the research work in high energy physics by the group at the University of California, Riverside. Work has been divided between hadron collider physics and e{sup +}-e{sup {minus}} collider physics, and theoretical work. The hadron effort has been heavily involved in the startup activities of the D-Zero detector, commissioning and ongoing redesign. The lepton collider work has included work on TPC/2{gamma} at PEP and the OPAL detector at LEP, as well as efforts on hadron machines.
Lepton-hadron physics: past, present and future
International Nuclear Information System (INIS)
Saxon, D.H.
1989-07-01
The scattering of leptons (e, μ, ν) hadrons at high momentum transfer has been the incisive probe of the internal dynamics of the proton. Point-like ''partons'' are found inside the proton. These have the electromagnetic and weak properties expected of quarks, and are in dynamical equilibrium with a sea of virtual quark-antiquark pairs and gluons, the quanta of the strong force. Neutrino scattering has probed the weak coupling of the quarks, and their parity-violating handedness. Weak neutral currents (coupling with the Z 0 boson) were discovered in neutrino scattering, and parity-violating γ-Z 0 interference was observed in electron-deuteron scattering. The higher momentum transfers that will be available at the HERA electron-proton storage ring, now under construction, will expand greatly the kinematic region available to search for new phenomena at and beyond the W,Z energy scale. (author)
PREFACE: Focus section on Hadronic Physics Focus section on Hadronic Physics
Roberts, Craig; Swanson, Eric
2007-07-01
illustrates how the structure of the nucleon is revealed. Reimer reviews how the Drell--Yan process can be used to explore the sea quark structure of nucleons, thereby probing such phenomena as flavour asymmetry in the nucleon and nuclear medium modification of nucleon properties. The exploitation of the B factories has led to a resurgence of interest in heavy quark spectroscopy. Concurrently, interest in light quark spectroscopy and gluonic excitations remains high, with several new experimental efforts in the planning or building stages. The current status of all of this is reviewed by Rosner. Finally, Vogelsang summarizes the status of polarized deep inelastic lepton-nucleon scattering experiments at RHIC and their impact on the theoretical understanding of nucleon helicity structure, gluon polarization in the nucleus, and transverse spin asymmetries. Of course, hadronic physics is a much broader subject than can be conveyed in this special focus section; advances in effective field theory, lattice gauge theory, generalised parton distributions and many other subfields are not covered here. Nevertheless, we hope that this focus section will help the reader appreciate the vitality, breadth of endeavour, and the phenomenological richness of hadronic physics.
Quarks and gluons in hadrons and nuclei
International Nuclear Information System (INIS)
Close, F.E.
1989-12-01
These lectures discuss the particle-nuclear interface -- a general introduction to the ideas and application of colored quarks in nuclear physics, color, the Pauli principle, and spin flavor correlations -- this lecture shows how the magnetic moments of hadrons relate to the underlying color degree of freedom, and the proton's spin -- a quark model perspective. This lecture reviews recent excitement which has led some to claim that in deep inelastic polarized lepton scattering very little of the spin of a polarized proton is due to its quarks. This lecture discusses the distribution functions of quarks and gluons in nucleons and nuclei, and how knowledge of these is necessary before some quark-gluon plasma searches can be analyzed. 56 refs., 2 figs
A Large Hadron Electron Collider at CERN
Abelleira Fernandez, J L; Adzic, P; Akay, A N; Aksakal, H; Albacete, J L; Allanach, B; Alekhin, S; Allport, P; Andreev, V; Appleby, R B; Arikan, E; Armesto, N; Azuelos, G; Bai, M; Barber, D; Bartels, J; Behnke, O; Behr, J; Belyaev, A S; Ben-Zvi, I; Bernard, N; Bertolucci, S; Bettoni, S; Biswal, S; Blumlein, J; Bottcher, H; Bogacz, A; Bracco, C; Bracinik, J; Brandt, G; Braun, H; Brodsky, S; Bruning, O; Bulyak, E; Buniatyan, A; Burkhardt, H; Cakir, I T; Cakir, O; Calaga, R; Caldwell, A; Cetinkaya, V; Chekelian, V; Ciapala, E; Ciftci, R; Ciftci, A K; Cole, B A; Collins, J C; Dadoun, O; Dainton, J; Roeck, A.De; d'Enterria, D; DiNezza, P; Dudarev, A; Eide, A; Enberg, R; Eroglu, E; Eskola, K J; Favart, L; Fitterer, M; Forte, S; Gaddi, A; Gambino, P; Garcia Morales, H; Gehrmann, T; Gladkikh, P; Glasman, C; Glazov, A; Godbole, R; Goddard, B; Greenshaw, T; Guffanti, A; Guzey, V; Gwenlan, C; Han, T; Hao, Y; Haug, F; Herr, W; Herve, A; Holzer, B J; Ishitsuka, M; Jacquet, M; Jeanneret, B; Jensen, E; Jimenez, J M; Jowett, J M; Jung, H; Karadeniz, H; Kayran, D; Kilic, A; Kimura, K; Klees, R; Klein, M; Klein, U; Kluge, T; Kocak, F; Korostelev, M; Kosmicki, A; Kostka, P; Kowalski, H; Kraemer, M; Kramer, G; Kuchler, D; Kuze, M; Lappi, T; Laycock, P; Levichev, E; Levonian, S; Litvinenko, V N; Lombardi, A; Maeda, J; Marquet, C; Mellado, B; Mess, K H; Milanese, A; Milhano, J G; Moch, S; Morozov, I I; Muttoni, Y; Myers, S; Nandi, S; Nergiz, Z; Newman, P R; Omori, T; Osborne, J; Paoloni, E; Papaphilippou, Y; Pascaud, C; Paukkunen, H; Perez, E; Pieloni, T; Pilicer, E; Pire, B; Placakyte, R; Polini, A; Ptitsyn, V; Pupkov, Y; Radescu, V; Raychaudhuri, S; Rinolfi, L; Rizvi, E; Rohini, R; Rojo, J; Russenschuck, S; Sahin, M; Salgado, C A; Sampei, K; Sassot, R; Sauvan, E; Schaefer, M; Schneekloth, U; Schorner-Sadenius, T; Schulte, D; Senol, A; Seryi, A; Sievers, P; Skrinsky, A N; Smith, W; South, D; Spiesberger, H; Stasto, A M; Strikman, M; Sullivan, M; Sultansoy, S; Sun, Y P; Surrow, B; Szymanowski, L; Taels, P; Tapan, I; Tasci, T; Tassi, E; Kate, H.Ten; Terron, J; Thiesen, H; Thompson, L; Thompson, P; Tokushuku, K; Tomas Garcia, R; Tommasini, D; Trbojevic, D; Tsoupas, N; Tuckmantel, J; Turkoz, S; Trinh, T N; Tywoniuk, K; Unel, G; Ullrich, T; Urakawa, J; VanMechelen, P; Variola, A; Veness, R; Vivoli, A; Vobly, P; Wagner, J; Wallny, R; Wallon, S; Watt, G; Weiss, C; Wiedemann, U A; Wienands, U; Willeke, F; Xiao, B W; Yakimenko, V; Zarnecki, A F; Zhang, Z; Zimmermann, F; Zlebcik, R; Zomer, F; CERN. Geneva. LHeC Department
2012-01-01
This document provides a brief overview of the recently published report on the design of the Large Hadron Electron Collider (LHeC), which comprises its physics programme, accelerator physics, technology and main detector concepts. The LHeC exploits and develops challenging, though principally existing, accelerator and detector technologies. This summary is complemented by brief illustrations of some of the highlights of the physics programme, which relies on a vastly extended kinematic range, luminosity and unprecedented precision in deep inelastic scattering. Illustrations are provided regarding high precision QCD, new physics (Higgs, SUSY) and electron-ion physics. The LHeC is designed to run synchronously with the LHC in the twenties and to achieve an integrated luminosity of O(100) fb$^{-1}$. It will become the cleanest high resolution microscope of mankind and will substantially extend as well as complement the investigation of the physics of the TeV energy scale, which has been enabled by the LHC.
QCD studies at the hadron colliders
International Nuclear Information System (INIS)
Flaugher, B.L.
1990-01-01
Two hadron collider experiments are actively pursuing QCD jet analyses. They are CDF, with a √s = 1800 GeV, and UA2, with a √s = 630 GeV. Recent results from these collaborations are discussed. The inclusive jet spectrum, dijet mass and angular distribution are compared to QCD predictions and used to set limits on quark substructure. Data from both experiments are compared to the O(α s 3 ) calculations for the inclusive jet cross section. Studies of 3-jet, 4-jet and 5-jet events are described. A limit is set on the cross section for double parton scattering from the UA2 4-jet analysis. The inclusive photon cross section has been measured by both CDF and UA2 and is compared to theoretical predictions. 13 refs., 17 figs., 1 tab
Hard photoproduction of multiparticle hadronic final states
International Nuclear Information System (INIS)
Paul, E.
1992-02-01
Recent results from fixed-target experiments on the photoproduction of hadrons have shown that pointlike photon interaction processes of lowest order in QCD can be studied. These are the flavour-dependent γg-fusion process which is the keyprocess to explore the gluon structure function of the nucleon at small x g and the QCD-Compton process which is a tool to study gluon fragmentation. The status of experimental results and comparison to QCD prediction is reviewed. The γg-fusion process will be measured in ep scatterings with almost real photons at HERA photon energies (equivalent to up to 50 TeV in the rest frame of the proton) down to x g > or approx. 10 -4 . Resolved (partonlike) photon interactions are predicted to be measurable at these high energies, too. (orig.)
The theory of deeply inelastic scattering
International Nuclear Information System (INIS)
Bluemlein, J.
2012-01-01
The nucleon structure functions probed in deep-inelastic scattering at large virtualities form an important tool to test Quantum Chromdynamics (QCD) through precision measurements of the strong coupling constant α s (M Z 2 ) and the different parton distribution functions. The exact knowledge of these quantities is also of importance for all precision measurements at hadron colliders. During the last two decades very significant progress has been made in performing precision calculations. We review the theoretical status reached for both unpolarized and polarized lepton-hadron scattering based on perturbative QCD. (orig.)
The theory of deeply inelastic scattering
Energy Technology Data Exchange (ETDEWEB)
Bluemlein, J.
2012-08-31
The nucleon structure functions probed in deep-inelastic scattering at large virtualities form an important tool to test Quantum Chromdynamics (QCD) through precision measurements of the strong coupling constant {alpha}{sub s}(M{sub Z}{sup 2}) and the different parton distribution functions. The exact knowledge of these quantities is also of importance for all precision measurements at hadron colliders. During the last two decades very significant progress has been made in performing precision calculations. We review the theoretical status reached for both unpolarized and polarized lepton-hadron scattering based on perturbative QCD. (orig.)
Large Hadron Collider nears completion
2008-01-01
Installation of the final component of the Large Hadron Collider particle accelerator is under way along the Franco-Swiss border near Geneva, Switzerland. When completed this summer, the LHC will be the world's largest and most complex scientific instrument.
The CMS Outer Hadron Calorimeter
Acharya, Bannaje Sripathi; Banerjee, Sunanda; Banerjee, Sudeshna; Bawa, Harinder Singh; Beri, Suman Bala; Bhandari, Virender; Bhatnagar, Vipin; Chendvankar, Sanjay; Deshpande, Pandurang Vishnu; Dugad, Shashikant; Ganguli, Som N; Guchait, Monoranjan; Gurtu, Atul; Kalmani, Suresh Devendrappa; Kaur, Manjit; Kohli, Jatinder Mohan; Krishnaswamy, Marthi Ramaswamy; Kumar, Arun; Maity, Manas; Majumder, Gobinda; Mazumdar, Kajari; Mondal, Naba Kumar; Nagaraj, P; Narasimham, Vemuri Syamala; Patil, Mandakini Ravindra; Reddy, L V; Satyanarayana, B; Sharma, Seema; Singh, B; Singh, Jas Bir; Sudhakar, Katta; Tonwar, Suresh C; Verma, Piyush
2006-01-01
The CMS hadron calorimeter is a sampling calorimeter with brass absorber and plastic scintillator tiles with wavelength shifting fibres for carrying the light to the readout device. The barrel hadron calorimeter is complemented with a outer calorimeter to ensure high energy shower containment in CMS and thus working as a tail catcher. Fabrication, testing and calibrations of the outer hadron calorimeter are carried out keeping in mind its importance in the energy measurement of jets in view of linearity and resolution. It will provide a net improvement in missing $\\et$ measurements at LHC energies. The outer hadron calorimeter has a very good signal to background ratio even for a minimum ionising particle and can hence be used in coincidence with the Resistive Plate Chambers of the CMS detector for the muon trigger.
Quark confinement and hadronic interactions
International Nuclear Information System (INIS)
Lenz, F.
1985-01-01
With the possibility for 'exact' calculations within the framework of a fundamental theory, QCD, the role of models in strong interaction physics is changing radically. The relevance of detailed numerical model studies is diminishing with the development of those exact, numerical approaches to QCD. On the other hand, the insight gained from such purely numerical studies is necessarily limited and must be complemented by the more qualitative but also more intuitive insight gained from model studies. In particular, the subject of hadron-hadron interactions requires model studies to relate the wide variety of strong interaction physics to the fundamental properties of strong interaction physics. The author reports on such model studies of the hadron-hadron interaction
Hadron energy resolution at ICAL
International Nuclear Information System (INIS)
Devi, Moon Moon; Ghosh, Anushree; Kaur, Daljeet; Mohan, Lakshmi S.
2013-01-01
We have performed a simulation study for determining the hadron energy resolution of INO-ICAL detector within a GEANT4 based simulation framework. We do this by propagating single pions from a fixed or a randomised vertex, as also with the NUANCE (neutrino event generator) generated events in which hadrons are produced in the energy range (0.5 ≤ E ≤ 15 GeV). Hadron interactions produce a shower of hits inside the detector. The energy of hadrons can therefore be reconstructed only by taking these hits into account. Hit distribution for each energy and angle bin has been obtained and analyzed. In order to find the suitable fit for such hit distributions a comparative study has been performed by applying different fit functions and results will be shown
Hadron seagulls and parton jets
International Nuclear Information System (INIS)
Satz, H.; Zarmi, Y.
1976-01-01
For the lepton production of hadrons in the current fragmentation region it was recently shown that the two-level partonic picture leads to a broadening of the average transverse momentum of the observed secondaries. This ''seagull'' effect is well known for hadron-hadron interactions. In the note it is considered the possibility that parton arguments can explain it here as well and it is discussed what information on the constituent structure of hadrons can be obtained through an investigation of the seagull effect from such a point of view. It is shown that a non trivial seagull effect is a consequence of a simple two step production mechanism and the parton model predicts significant differences between baryon, meson and virtual-photon fragmentation seagull
Fixed target hadron production measurements
Panman, J
2009-01-01
The knowledge of light hadron production cross-sections in proton-nucleus interactions is an important prerequisite to the analysis of a wide variety of experiments. One of the important limiting factors for the precision of accelerator based and atmospheric neutrino oscillation experiments is the uncertainty in the composition and spectrum of the neutrino flux. Cosmic-ray experiments detecting extensive air-showers can greatly improve their ability to interpret the data when precise hadron production spectra are available over a large range of energies. Dedicated hadron production experiments have been taking data recently and are now publishing their results. Other experiments have just started their data-taking and plan to supply measurements which can significantly extend the kinematic range in which data will be available. Early measurements at the LHC can extend this range to much higher energies than available up to now. Recent results will be shown and compared with hadronic production models. An outl...
Topological objects in hadron physics
International Nuclear Information System (INIS)
Rho, M.
1988-01-01
The notion of topological objects in hadronic physics is discussed, with emphasis on the role of the Wess-Zumino term and induced transmutation of quantum numbers in chiral bag models. Some applications to nuclear systems are given
B factory with hadron colliders
International Nuclear Information System (INIS)
Lockyer, N.S.
1990-01-01
The opportunities to study B physics in a hadron collider are discussed. Emphasis is placed on the technological developments necessary for these experiments. The R and D program of the Bottom Collider Detector group is reviewed. (author)
The surface between QCD and Hadron physics
International Nuclear Information System (INIS)
Von Geramb, H.V.; Bayansan, D.
2005-01-01
The relativistic potential concept is fostered for the description of nucleon-nucleon (NN) interaction and scattering for energies 0 < T Lab ≤ 3 GeV. We use a formalism, developed by Crater and Van Alstine, for two coupled spin 1/2 particles in terms of coupled Dirac equations with constraint instant form dynamics. Sets of coupled Dirac equations are used and reduced into partial wave Schr¨odinger type equations. We study np and pp scattering phase shifts for energies 0 to 3 GeV and the deuteron bound state. The interactions are inspired and parameterized in terms of π, η, ρ, ω and σ meson exchanges for which we adjust coupling constants. This yields, in the first instant, high quality fits to the Arndt phase shifts 0 to 300 MeV. Second, the potentials show a universal, independent from angular momentum, core potential which is generated with the relativistic meson exchange dynamics. Extrapolations towards higher energies, up to T Lab equal 3 GeV, allow to separate a QCD dominated short range zone as well as inelastic nucleon excitation mechanism contributing to meson production. A local short range optical model, replacing the short range meson exchange Dirac potential, produces exact agreement between theoretical and phase shifts data. The optical model potentials reflect short lived complex multi hadronic intermediate structure formation of which the optical model parameters give a consistent picture. This phenomenological approach shows the need to describe the short range NN interaction zone r < 0.8 fm with a microscopic model. It implies using the quark content of the nucleons and gluon exchange as well as the need for a microscopic description of intermediate Δ and hadron pair excitations. The conventional soft or hard core NN potentials remain valid for an effective short range low energy description
A phenomenological π-p scattering length from pionic hydrogen
International Nuclear Information System (INIS)
Ericson, T.E.O.; Loiseau, B.; Wycech, S.
2004-01-01
We derive a closed, model independent, expression for the electromagnetic correction factor to a phenomenological hadronic scattering length a h extracted from a hydrogenic atom. It is obtained in a non-relativistic approach and in the limit of a short ranged hadronic interaction to terms of order α 2 logα using an extended charge distribution. A hadronic πN scattering length a h π - p =0.0870(5)m π -1 is deduced leading to a πNN coupling constant from the GMO relation g c 2 /(4π)=14.04(17)
A phenomenological $\\pi^{-}p$ scattering length from pionic hydrogen
Ericson, Torleif Eric Oskar; Wycech, S
2004-01-01
We derive a closed, model independent, expression for the electromagnetic correction factor to a phenomenological hadronic scattering length a/sup h/ extracted from a hydrogenic atom. It is obtained in a non-relativistic approach and in the limit of a short ranged hadronic interaction to terms of order alpha /sup 2/ log alpha using an extended charge distribution. A hadronic pi N scattering length a/sub pi -p//sup h/ = 0.0870(5)m/sub pi //sup -1/ is deduced leading to a pi NN coupling constant from the GMO relation g/sub c //sup 2//(4 pi ) = 14.04(17). (28 refs).
Japan Hadron Facility (JHF) project
International Nuclear Information System (INIS)
Nagamiya, S.
1999-01-01
The Japan Hadron Facility (JHF) is the next accelerator project proposed at KEK to promote exciting sciences by utilising high-intensity proton beams. The project is characterised by three unique features: hadronic beams of the world's highest intensity; a variety of beams from one accelerator complex; frontier sciences to cover a broad research area including nuclear physics, particle physics, material sciences and life sciences by utilising a common accelerator complex. (author)
Anisotropic superfluidity of hadronic matter
International Nuclear Information System (INIS)
Chela Flores, J.
1977-10-01
From a model of strong interactions with important general features (f-g model) and from recent experiments of Rudnick and co-workers on thin films of helium II, hadronic matter is considered as a new manifestation of anisotropic superfluidity. In order to test the validity of the suggestion, some qualitative features of multiparticle production of hadrons are considered, and found to have a natural explanation. A prediction is made following a recent experiment on π + p collisions
The ATLAS hadronic tau trigger
International Nuclear Information System (INIS)
Shamim, Mansoora
2012-01-01
The extensive tau physics programs of the ATLAS experiment relies heavily on trigger to select hadronic decays of tau lepton. Such a trigger is implemented in ATLAS to efficiently collect signal events, while keeping the rate of multi-jet background within the allowed bandwidth. This contribution summarizes the performance of the ATLAS hadronic tau trigger system during 2011 data taking period and improvements implemented for the 2012 data collection.
International Nuclear Information System (INIS)
Davier, M.
1999-12-01
Hadronic decays of the τ lepton provide a clean source to study hadron dynamics in an energy regime dominated by resonances, with the interesting information captured in the spectral functions. Recent results on exclusive channels are reviewed. Inclusive spectral functions are the basis for QCD analyses, delivering an accurate determination of the strong coupling constant and quantitative information on nonperturbative contributions. Strange decays yield a determination of the strange quark mass. (author)
Energy Technology Data Exchange (ETDEWEB)
Davier, M
1999-12-01
Hadronic decays of the {tau} lepton provide a clean source to study hadron dynamics in an energy regime dominated by resonances, with the interesting information captured in the spectral functions. Recent results on exclusive channels are reviewed. Inclusive spectral functions are the basis for QCD analyses, delivering an accurate determination of the strong coupling constant and quantitative information on nonperturbative contributions. Strange decays yield a determination of the strange quark mass. (author)
A. Skuja
Since the beginning of 2007, HCAL has made significant progress in the installation and commissioning of both hardware and software. A large fraction of the physical Hadron Calorimeter modules have been installed in UX5. In fact, the only missing pieces are HE- and part of HO. The HB+/- were installed in the cryostat in March. HB scintillator layer-17 was installed above ground before the HB were lowered. The HB- scintillator layer-0 was installed immediately after completion of EB- installation. HF/HCAL Commissioning The commissioning and checkout of the HCAL readout electronics is also proceeding at a rapid pace in Bldg. 904 and USC55. All sixteen crates of HCAL VME readout electronics have been commissioned and certified for service. Fifteen are currently operating in the S2 level of USC55. The last crate is being used for firmware development in the Electronics Integration Facility in 904. All installed crates are interfaced to their VME computers and receive synchronous control from the fully-equipp...
High resolution hadron calorimetry
International Nuclear Information System (INIS)
Wigmans, R.
1987-01-01
The components that contribute to the signal of a hadron calorimeter and the factors that affect its performance are discussed, concentrating on two aspects; energy resolution and signal linearity. Both are decisively dependent on the relative response to the electromagnetic and the non-electromagnetic shower components, the e/h signal ratio, which should be equal to 1.0 for optimal performance. The factors that determine the value of this ratio are examined. The calorimeter performance is crucially determined by its response to the abundantly present soft neutrons in the shower. The presence of a considerable fraction of hydrogen atoms in the active medium is essential for achieving the best possible results. Firstly, this allows one to tune e/h to the desired value by choosing the appropriate sampling fraction. And secondly, the efficient neutron detection via recoil protons in the readout medium itself reduces considerably the effect of fluctuations in binding energy losses at the nuclear level, which dominate the intrinsic energy resolution. Signal equalization, or compensation (e/h = 1.0) does not seem to be a property unique to 238 U, but can also be achieved with lead and probably even iron absorbers. 21 refs.; 19 figs
Late effects from hadron therapy
Energy Technology Data Exchange (ETDEWEB)
Blakely, Eleanor A.; Chang, Polly Y.
2004-06-01
Successful cancer patient survival and local tumor control from hadron radiotherapy warrant a discussion of potential secondary late effects from the radiation. The study of late-appearing clinical effects from particle beams of protons, carbon, or heavier ions is a relatively new field with few data. However, new clinical information is available from pioneer hadron radiotherapy programs in the USA, Japan, Germany and Switzerland. This paper will review available data on late tissue effects from particle radiation exposures, and discuss its importance to the future of hadron therapy. Potential late radiation effects are associated with irradiated normal tissue volumes at risk that in many cases can be reduced with hadron therapy. However, normal tissues present within hadron treatment volumes can demonstrate enhanced responses compared to conventional modes of therapy. Late endpoints of concern include induction of secondary cancers, cataract, fibrosis, neurodegeneration, vascular damage, and immunological, endocrine and hereditary effects. Low-dose tissue effects at tumor margins need further study, and there is need for more acute molecular studies underlying late effects of hadron therapy.
Energy Technology Data Exchange (ETDEWEB)
Hermann, Roman
2009-09-05
The spin structure of the nucleon is investigated at the COMPASS experiment at the CERN SPS using polarized muons scattering off polarized nucleons. The contribution of the quarks to nucleon spin, as measured in the inclusive deep-inelastic scattering, is not sufficient to explain the spin of the nucleon. Thus it has to be clarified how the gluon polarization and the angular momenta of quarks and gluons contribute to the spin of the nucleon. Since the gluon polarization can only be estimated from the Q{sup 2}-dependence of inclusive deep inelastic asymmetries, a direct measurement of the gluon polarization is mandatory. The COMPASS collaboration determines the gluon polarization from cross section asymmetries in photon-gluon fusion processes using open charm production or the production of hadron pairs with large transverse momenta. This thesis presents a measurement of the gluon polarization using the COMPASS data of the years 2003 and 2004. The events with large virtuality, Q{sup 2}>1 GeV{sup 2}/c{sup 2}, and hadron pairs with large transverse momenta, p perpendicular to > 0.7 GeV/c have been used in the analysis. The photon-nucleon asymmetry was determined by using a weighted double ratio method of the selected events. The cut on p perpendicular to > 0.7 GeV/c suppresses leading order processes, so that the obtained asymmetry can be directly linked to the gluon polarization, if the analyzing power and the photon-gluon fusion fraction is known. The measured value is very small and compatible with a vanishing gluon polarization. To avoid false asymmetries, which could be caused by a change of the detector acceptances double ratios were analyzed, where the cross section cancels, and only detector asymmetries remain. It is shown that the COMPASS spectrometer was stable during the time of data taking. For the computation of the analyzing power Monte Carlo events were generated using the LEPTO and the COMGeant software packages. In this context a good MC description
International Nuclear Information System (INIS)
Yazaki, K.
1995-01-01
The nuclear or color transparency in initial and final state interactions of protons, involved in high energy semi-exclusive processes such as (, e ' p) and (p, 2 p) reactions, is discussed first in the conventional Glauber approach and then in models taking account of the proton internal dynamics. The conventional approach includes nuclear many-body effects as well as multiple scattering effects and serves as a reference for finding the roles of the internal dynamics in the observed transparency. The models predict non-trivial effects on the transparency. (author)
Statistical hadronization and hadronic micro-canonical ensemble II
International Nuclear Information System (INIS)
Becattini, F.; Ferroni, L.
2004-01-01
We present a Monte Carlo calculation of the micro-canonical ensemble of the ideal hadron-resonance gas including all known states up to a mass of about 1.8 GeV and full quantum statistics. The micro-canonical average multiplicities of the various hadron species are found to converge to the canonical ones for moderately low values of the total energy, around 8 GeV, thus bearing out previous analyses of hadronic multiplicities in the canonical ensemble. The main numerical computing method is an importance sampling Monte Carlo algorithm using the product of Poisson distributions to generate multi-hadronic channels. It is shown that the use of this multi-Poisson distribution allows for an efficient and fast computation of averages, which can be further improved in the limit of very large clusters. We have also studied the fitness of a previously proposed computing method, based on the Metropolis Monte Carlo algorithm, for event generation in the statistical hadronization model. We find that the use of the multi-Poisson distribution as proposal matrix dramatically improves the computation performance. However, due to the correlation of subsequent samples, this method proves to be generally less robust and effective than the importance sampling method. (orig.)
International Nuclear Information System (INIS)
Alonso, J.R.
1995-05-01
Radiation therapy with ''hadrons'' (protons, neutrons, pions, ions) has accrued a 55-year track record, with by now over 30,000 patients having received treatments with one of these particles. Very good, and in some cases spectacular results are leading to growth in the field in specific well-defined directions. The most noted contributor to success has been the ability to better define and control the radiation field produced with these particles, to increase the dose delivered to the treatment volume while achieving a high degree of sparing of normal tissue. An additional benefit is the highly-ionizing, character of certain beams, leading to creater cell-killing potential for tumor lines that have historically been very resistant to radiation treatments. Until recently these treatments have been delivered in laboratories and research centers whose primary, or original mission was physics research. With maturity in the field has come both the desire to provide beam facilities more accessible to the clinical setting, of a hospital, as well as achieving, highly-efficient, reliable and economical accelerator and beam-delivery systems that can make maximum advantage of the physical characteristics of these particle beams. Considerable work in technology development is now leading, to the implementation of many of these ideas, and a new generation of clinically-oriented facilities is beginning to appear. We will discuss both the physical, clinical and technological considerations that are driving these designs, as well as highlighting, specific examples of new facilities that are either now treating, patients or that will be doing so in the near future
Charge-symmetry-breaking effects from phase-shift analysis of elastic πsup(+-4)He scattering
International Nuclear Information System (INIS)
Khankhasayev, M.Kh.; Nichitiu, F.; Sapozhnikov, M.G.
1986-01-01
A phase-shift analysis of elastic πsup(+-4)He scattering at energies 20-160 MeV was performed to determine pure hadronic phase shifts. No statistically significant difference between the hadronic phase shifts deduced from π +4 He and π -4 He scattering was observed. (orig.)
Glauber-Sitenko screening in elastic and inelastic diffraction of hadrons and light nuclei
International Nuclear Information System (INIS)
Fazylov, M.I.; Yuldashev, B.S.; Azhniyazova, G.T.; Ismatov, E.I.; Sartbay, T.; Kurmanbay, M.S.; Tskhay, K.V.
2004-01-01
Full text: In this work a method for differential and integral cross-sections of diffraction interactions of hadrons and light nuclei on heavy nuclei was developed. For HeA-interactions the effect of pair, three-fold and four-fold screening was estimated. The sensitivity of analysis of hadron-nucleus and nucleus-nucleus scattering characteristics was conducted in order to select parameterization of a single particle nuclear densities. It is demonstrated that differential cross-sections of hadron-nucleus and nucleus-nucleus scattering are less sensitive to nuclear structure than differential cross-section of nucleus-nucleus Coulomb scattering. A simple parameterization of nuclear density allowing one to have an analytical representation for width function T(ρ ) is suggested. By using this function it is possible to simplify significantly calculations of physical characteristics of hadron-nucleus and nucleus-nucleus interactions. Phenomenological procedure for Coulomb effects consideration in nucleus-nucleus scattering is developed. In frames of optical approximation the expression for differential and integral cross-sections of quasi-elastic scattering are obtained. It is shown that the optical approximation is the most effective for quasi-elastic scattering calculation. For elastic and inelastic diffraction of hadrons on nucleons the ration of total cross-sections σ el /σ t , σ el /b and σ in /b via ratio of a real and imaginary parts of the scattering amplitude forward δ (t) are obtained, and it is shown that δ (t) significantly influences on the structure of differential cross-section of the interaction
Glauber-Sitenko screening in elastic and inelastic diffraction of hadrons and light nuclei
International Nuclear Information System (INIS)
Yuldashev, B.S.; Fazilova, Z.F.; Ismatov, E.I.; Ajniyazova, G.T.; Kurmanbai, M.S.; Shunkeev, K.Sh.; Medeuova, A.B.; Tskhai, K.V.
2004-01-01
In this work a method for differential and integral cross-sections of diffraction interactions of hadrons and light nuclei on heavy nuclei was developed. For HeA-interactions the effect of pair, three-fold and four-fold screening was estimated. The sensitivity of analysis of hadron-nucleus and nucleus-nucleus scattering characteristics was conducted in order to select parameterization of a single particle nuclear densities. It is demonstrated that differential cross-sections of hadron-nucleus and nucleus-nucleus scattering are less sensitive to nuclear structure than differential cross-section of nucleus-nucleus Coulomb scattering. A simple parameterization of nuclear density allowing one to have an analytical representation for width function T(ρ) is suggested. By using this function it is possible to simplify significantly calculations of physical characteristics of hadron-nucleus and nucleus-nucleus interactions. Phenomenological procedure for Coulomb effects consideration in nucleus-nucleus scattering is developed. In frames of optical approximation the expression for differential and integral cross-sections of quasi-elastic scattering are obtained. It is shown that the optical approximation is the most effective for quasi-elastic scattering calculation. For elastic and inelastic diffraction of hadrons on nucleons the ration of total cross-sections σ el /σ t , σ el /b and σ in /b via ratio of a real and imaginary parts of the scattering amplitude forward δ (t) are obtained, and it is shown that δ (t) significantly influences on the structure of differential cross-section of the interaction
Identifying Multiquark Hadrons from Heavy Ion Collisions
International Nuclear Information System (INIS)
Cho, Sungtae; Furumoto, Takenori; Yazaki, Koichi; Hyodo, Tetsuo; Jido, Daisuke; Ohnishi, Akira; Ko, Che Ming; Lee, Su Houng; Nielsen, Marina; Sekihara, Takayasu; Yasui, Shigehiro
2011-01-01
Identifying hadronic molecular states and/or hadrons with multiquark components either with or without exotic quantum numbers is a long-standing challenge in hadronic physics. We suggest that studying the production of these hadrons in relativistic heavy ion collisions offers a promising resolution to this problem as yields of exotic hadrons are expected to be strongly affected by their structures. Using the coalescence model for hadron production, we find that, compared to the case of a nonexotic hadron with normal quark numbers, the yield of an exotic hadron is typically an order of magnitude smaller when it is a compact multiquark state and a factor of 2 or more larger when it is a loosely bound hadronic molecule. We further find that some of the newly proposed heavy exotic states could be produced and realistically measured in these experiments.
A Large Hadron Electron Collider at CERN, Physics, Machine, Detector
Adolphson, C
2011-01-01
The physics programme and the design are described of a new electron-hadron collider, the LHeC, in which electrons of $60$ to possibly $140$\\,GeV collide with LHC protons of $7000$\\,GeV. With an $ep$ design luminosity of about $10^{33}$\\,cm$^{-2}$s$^{-1}$, the Large Hadron Electron Collider exceeds the integrated luminosity collected at HERA by two orders of magnitude and the kinematic range by a factor of twenty in the four-momentum squared, $Q^2$, and in the inverse Bjorken $x$. The physics programme is devoted to an exploration of the energy frontier, complementing the LHC and its discovery potential for physics beyond the Standard Model with high precision deep inelastic scattering (DIS) measurements. These are projected to solve a variety of fundamental questions in strong and electroweak interactions. The LHeC thus becomes the world's cleanest high resolution microscope, designed to continue the path of deep inelastic lepton-hadron scattering into unknown areas of physics and kinematics. The physics ...
Central and peripheral interactions of hadrons
Energy Technology Data Exchange (ETDEWEB)
Dremin, I.M. [Lebedev Physics Institute, Moscow (Russian Federation); National Research Nuclear University ' ' MEPhI' ' , Moscow (Russian Federation); Nechitailo, V.A. [Lebedev Physics Institute, Moscow (Russian Federation); White, S.N. [CERN, Geneva (Switzerland)
2017-12-15
Surprisingly enough, the ratio of elastic to inelastic cross sections of proton interactions increases with energy in the interval corresponding to ISR→LHC (i.e. from 10 to 10{sup 4} GeV). That leads to special features of their spatial interaction region at these and higher energies. Within the framework of some phenomenological models, we show how the particular ranges of the transferred momenta measured in elastic scattering experiments expose the spatial features of the inelastic interaction region according to the unitarity condition. The difference between their predictions at higher energies is discussed. The notion of central and peripheral collisions of hadrons is treated in terms of the impact-parameter description. It is shown that the shape of the differential cross section in the diffraction cone is mostly determined by collisions with intermediate impact parameters. Elastic scattering at very small transferred momenta is sensitive to peripheral processes with large impact parameters. The role of central collisions in the formation of the diffraction cone is less significant. (orig.)
Czech Academy of Sciences Publication Activity Database
Aaboud, M.; Aad, G.; Abbott, B.; Chudoba, Jiří; Hejbal, Jiří; Hladík, Ondřej; Jakoubek, Tomáš; Kepka, Oldřich; Kupčo, Alexander; Kůs, Vlastimil; Lokajíček, Miloš; Lysák, Roman; Marčišovský, Michal; Mikeštíková, Marcela; Němeček, Stanislav; Penc, Ondřej; Šícho, Petr; Staroba, Pavel; Svatoš, Michal; Taševský, Marek
2017-01-01
Roč. 2017, č. 11 (2017), s. 1-51, č. článku 062. ISSN 1029-8479 Institutional support: RVO:68378271 Keywords : B physics * Hadron-Hadron scattering (experiments) * CERN LHC Coll Subject RIV: BF - Elementary Particles and High Energy Physics OBOR OECD: Particles and field physics Impact factor: 6.063, year: 2016
Czech Academy of Sciences Publication Activity Database
Aaboud, M.; Aad, G.; Abbott, B.; Chudoba, Jiří; Havránek, Miroslav; Hejbal, Jiří; Jakoubek, Tomáš; Kepka, Oldřich; Kupčo, Alexander; Kůs, Vlastimil; Lokajíček, Miloš; Lysák, Roman; Marčišovský, Michal; Mikeštíková, Marcela; Němeček, Stanislav; Penc, Ondřej; Šícho, Petr; Staroba, Pavel; Svatoš, Michal; Taševský, Marek; Vrba, Václav
2017-01-01
Roč. 2017, č. 9 (2017), s. 1-41, č. článku 118. ISSN 1029-8479 Institutional support: RVO:68378271 Keywords : Hadron-Hadron scattering (experiments) * top physics * ATLAS * CERN Subject RIV: BF - Elementary Particles and High Energy Physics OBOR OECD: Particles and field physics Impact factor: 6.063, year: 2016
Czech Academy of Sciences Publication Activity Database
Abelev, B.; Adam, J.; Adamová, Dagmar; Bielčík, J.; Bielčíková, Jana; Čepila, J.; Křelina, M.; Krus, M.; Kushpil, Svetlana; Kushpil, Vasilij; Mareš, Jiří A.; Pachr, M.; Petráček, V.; Petráň, M.; Polák, Karel; Pospíšil, V.; Šmakal, R.; Šumbera, Michal; Tlustý, D.; Vajzer, Michal; Wagner, V.; Zach, Č.; Závada, Petr
2012-01-01
Roč. 2012, č. 11 (2012), s. 065 ISSN 1126-6708 R&D Projects: GA MŠk LA08015 Institutional support: RVO:61389005 ; RVO:68378271 Keywords : hadron-hadron scattering * ALICE Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 5.618, year: 2012
Deep Inelastic Scattering at the Amplitude Level
International Nuclear Information System (INIS)
Brodsky, Stanley J.
2005-01-01
The deep inelastic lepton scattering and deeply virtual Compton scattering cross sections can be interpreted in terms of the fundamental wavefunctions defined by the light-front Fock expansion, thus allowing tests of QCD at the amplitude level. The AdS/CFT correspondence between gauge theory and string theory provides remarkable new insights into QCD, including a model for hadronic wavefunctions which display conformal scaling at short distances and color confinement at large distances
Srivastava, D K; Kvasnikova, I; Gale, C; Srivastava, Dinesh Kumar; Sinha, Bikash; Kvasnikova, Ioulia; Gale, Charles
2002-01-01
The production of single photons in $Pb+Pb$ collisions at the CERN SPS as measured by the WA98 experiment is analysed. A very good description of the data is obtained if a quark gluon plasma is assumed to be formed initially, which expands, cools, hadronizes, and undergoes freeze-out. A rich hadronic equation of state is used and the transverse expansion of the interacting system is taken into account. The recent estimates of photon production in quark-matter (at two loop level) along with the dominant reactions in the hadronic matter leading to photons are used. Most of the radiation of the photons is seen to arise from the quark-matter, which contributes dominantly through the mechanism of annihilation of quarks with scattering, and which in turn is possible only in a hot and dense plasma of quarks and gluons. The same treatment provides a very good description to hadronic spectra measured by several groups and the intermediate mass dileptons measured by the NA50 experiment, lending a strong support to the ...
Hocker, Andreas
1997-01-01
We present new results for the r hadronic spectral functions analysis using data accumulated by the ALEPH detector at LEP during the years 1991-94. The vector and the axial-vector spectral functions are determined from their respective unfolded, i.e., physical invariant mass spectra. The r vector and axial-vector hadronic widths and certain spectral moments are exploited to measure a, and nonperturbative contributions at the r mass scale. The best, and experimentally and theoretically most robust, determination of a,(Mr) is obtained from the inclusive (V + A) fit that yields a,(Mr) = 0.349 ± 0.018 giving a,(Mz) = 0.1 212 ± 0.0022 after the evolution to the mass of the Z boson. The approach of the Operator Product Expansion (OPE) is tested experimentally by means of an evolution of the r hadronic width to masses smaller than the r mass.
The COMPASS Hadron Spectroscopy Programme
Austregesilo, A
2011-01-01
COMPASS is a fixed-target experiment at the CERN SPS for the investigation of the structure and the dynamics of hadrons. The experimental setup features a large acceptance and high momentum resolution spectrometer including particle identification and calorimetry and is therefore ideal to access a broad range of different final states. Following the promising observation of a spin-exotic resonance during an earlier pilot run, COMPASS focused on light-quark hadron spectroscopy during the years 2008 and 2009. A data set, world leading in terms of statistics and resolution, has been collected with a 190GeV/c hadron beam impinging on either liquid hydrogen or nuclear targets. Spin-exotic meson and glueball candidates formed in both diffractive dissociation and central production are presently studied. Since the beam composition includes protons, the excited baryon spectrum is also accessible. Furthermore, Primakoff reactions have the potential to determine radiative widths of the resonances and to probe chiral pe...
Phenomenological studies of hadronic collisions
International Nuclear Information System (INIS)
van Zijl, M.
1987-04-01
Several aspects of hadronic collisions are studied in a phenomenological framework. A Monte Carlo model for initial state parton showers, using a backwards evolution scheme, is presented. Comparisons with experimental data and analytical calculations are made. The consequence of using different fragmentation model on the determination of α s is also investigated. It is found that the different fragmentation models lead to the reconstruction of significantly α s values. Finally the possibility of having several independent parton-parton interactions in a hadron-hadron collision is studied. A model is developed, which takes into account the effects of variable impact parameters. This is implemented in a Monte Carlo computer program and extensive comparisons with experimental data are carried out. There is clear evidence in favour of multiple interactions with variable impact parameters. (author)
Dijet imbalance in hadronic collisions
International Nuclear Information System (INIS)
Boer, Danieel; Mulders, Piet J.; Pisano, Cristian
2009-01-01
The imbalance of dijets produced in hadronic collisions has been used to extract the average transverse momentum of partons inside the hadrons. In this paper we discuss new contributions to the dijet imbalance that could complicate or even hamper this extraction. They are due to polarization of initial state partons inside unpolarized hadrons that can arise in the presence of nonzero parton transverse momentum. Transversely polarized quarks and linearly polarized gluons produce specific azimuthal dependences of the two jets that in principle are not suppressed. Their effects cannot be isolated just by looking at the angular deviation from the back-to-back situation; rather they enter jet broadening observables. In this way they directly affect the extraction of the average transverse momentum of unpolarized partons that is thought to be extracted. We discuss appropriately weighted cross sections to isolate the additional contributions.
On the hadron mass decomposition
Lorcé, Cédric
2018-02-01
We argue that the standard decompositions of the hadron mass overlook pressure effects, and hence should be interpreted with great care. Based on the semiclassical picture, we propose a new decomposition that properly accounts for these pressure effects. Because of Lorentz covariance, we stress that the hadron mass decomposition automatically comes along with a stability constraint, which we discuss for the first time. We show also that if a hadron is seen as made of quarks and gluons, one cannot decompose its mass into more than two contributions without running into trouble with the consistency of the physical interpretation. In particular, the so-called quark mass and trace anomaly contributions appear to be purely conventional. Based on the current phenomenological values, we find that in average quarks exert a repulsive force inside nucleons, balanced exactly by the gluon attractive force.
International Nuclear Information System (INIS)
Anderson, J.T.
1994-01-01
Without the spin interactions the hardron masses within a multiplet are degenerate. The light quark hadron degenerate mulitplet mass spectrum is extended from the 3 quark ground state multiplets at J P =0 - , 1/2 + , 1 - to include the excited states which follow the spinorial decomposition of SU(2)xSU(2). The mass scales for the 4, 5, 6, .. quark hadrons are obtained from the degenerate multiplet mass m 0 /M=n 2 /α with n=4, 5, 6, .. The 4, 5, 6, .. quark hadron degenerate multiplet masses follow by splitting of the heavy quark mass scales according to the spinorial decomposition of SU(2)xSU(2). (orig.)
On the hadron mass decomposition
Energy Technology Data Exchange (ETDEWEB)
Lorce, Cedric [Universite Paris-Saclay, Centre de Physique Theorique, Ecole Polytechnique, CNRS, Palaiseau (France)
2018-02-15
We argue that the standard decompositions of the hadron mass overlook pressure effects, and hence should be interpreted with great care. Based on the semiclassical picture, we propose a new decomposition that properly accounts for these pressure effects. Because of Lorentz covariance, we stress that the hadron mass decomposition automatically comes along with a stability constraint, which we discuss for the first time. We show also that if a hadron is seen as made of quarks and gluons, one cannot decompose its mass into more than two contributions without running into trouble with the consistency of the physical interpretation. In particular, the so-called quark mass and trace anomaly contributions appear to be purely conventional. Based on the current phenomenological values, we find that in average quarks exert a repulsive force inside nucleons, balanced exactly by the gluon attractive force. (orig.)
Hadron Contribution to Vacuum Polarisation
Davier, M; Malaescu, B; Zhang, Z
2016-01-01
Precision tests of the Standard Theory require theoretical predictions taking into account higher-order quantum corrections. Among these vacuum polarisation plays a predominant role. Vacuum polarisation originates from creation and annihilation of virtual particle–antiparticle states. Leptonic vacuum polarisation can be computed from quantum electrodynamics. Hadronic vacuum polarisation cannot because of the non-perturbative nature of QCD at low energy. The problem is remedied by establishing dispersion relations involving experimental data on the cross section for e+ e− annihilation into hadrons. This chapter sets the theoretical and experimental scene and reviews the progress achieved in the last decades thanks to more precise and complete data sets. Among the various applications of hadronic vacuum polarisation calculations, two are emphasised: the contribution to the anomalous magnetic moment of the muon, and the running of the fine structure constant α to the Z mass scale. They are fundamental ingre...
Diffraction scattering and the parton model in QCD
International Nuclear Information System (INIS)
White, A.
1985-01-01
Arguments are presented that the validity of the parton model for hadron scattering in QCD is directly related to the occurrence of the Critical Pomeron description of diffraction scattering. An attractive route suggested for Electroweak and Grand Unification is also briefly described
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.
Very high multiplicity hadron processes
International Nuclear Information System (INIS)
Mandzhavidze, I.; Sisakyan, A.
2000-01-01
The paper contains a description of a first attempt to understand the extremely inelastic high energy hadron collisions, when the multiplicity of produced hadrons considerably exceeds its mean value. Problems with existing model predictions are discussed. The real-time finite-temperature S-matrix theory is built to have a possibility to find model-free predictions. This allows one to include the statistical effects into consideration and build the phenomenology. The questions to experiment are formulated at the very end of the paper
Hadron structure from lattice QCD
International Nuclear Information System (INIS)
Schaefer, Andreas
2008-01-01
Some elements and current developments of lattice QCD are reviewed, with special emphasis on hadron structure observables. In principle, high precision experimental and lattice data provide nowadays a very detailled picture of the internal structure of hadrons. However, to relate both, a very good controle of perturbative QCD is needed in many cases. Finally chiral perturbation theory is extremely helpful to boost the precision of lattice calculations. The mutual need and benefit of all four elements: experiment, lattice QCD, perturbative QCD and chiral perturbation theory is the main topic of this review
Light Cone 2017 : Frontiers in Light Front Hadron Physics : Theory and Experiment.
2018-01-01
LC2017 belongs to a series of Light-Cone conferences, which started in 1991. Light Cone conferences are held each year under the auspices of the International Light Cone Advisory Committee (ILCAC) (http://www.ilcacinc.org). The main objective of the Light Cone conference series is to provide a timely update of the progress in light-front theory and its phenomenological applications. Light-front theory provides a suitable framework to calculate observables such as scattering amplitudes, decay rates, spin effects, parton distributions, and other hadronic observables. One of the themes of the conference will be the interface between theory and experiment in hadron physics. The main topics of the program are: o Hadron Physics at present and future colliders o Light Front Field Theory in QED and QCD o AdS/QCD, D Branes and Strings o Hadron Structure : TMDs, GPDs and PDFs o Lattice QCD o QCD at high temperature and density o Higher order QCD corrections
Deep-inelastic final states in a space-time description of shower development and hadronization
International Nuclear Information System (INIS)
Ellis, J.
1996-06-01
We extend a quantum kinetic approach to the description of hadronic showers in space, time and momentum space to deep-inelastic ep collisions, with particular reference to experiments at HERA. We follow the history of hard scattering events back to the initial hadronic state and forward to the formation of colour-singlet pre-hadronic clusters and their decays into hadrons. The time evolution of the space-like initial-state shower and the time-like secondary partons are treated similarly, and cluster formation is treated using a spatial criterion motivated by confinement and a non-perturbative model for hadronization. We calculate the time evolution of particle distributions in rapidity, transverse and longitudinal space. We also compare the transverse hadronic energy flow and the distribution of observed hadronic masses with experimental data from HERA, finding encouraging results, and discuss the background to large-rapidity-gap events. The techniques developed in this paper may be applied in the future to more complicated processes such as eA, pp, pA and AA collisions. (orig.)
Hadron Mass Effects for Kaon Production on deuteron
Guerrero, Juan
2017-09-01
The spin-independent cross section for semi-inclusive lepton-nucleon scattering are derived in the framework of collinear factorization, including the effects of the target and produced hadron masses at small momentum transfer squared Q2. At leading order, the cross section factorizes into products of parton distributions and fragmentation functions evaluated in terms of new, mass-dependent scaling variables. This talk focuses on Kaon production at HERMES and COMPASS kinematics. In particular, hadron mass corrections for integrated kaon multiplicities measured by the two collaborations are shown to sizeably reduce the apparent large discrepancy between the results for both experiments. This work was supported by the DOE contract No. DE-AC05-06OR23177, under which Jefferson Science Associates, LLC operates Jefferson Lab, and by the DOE Contract No. DE-SC008791.
Systematic approach to inclusive lepton pair production in hadronic collisions
International Nuclear Information System (INIS)
Lam, C.S.; Tung, W.
1978-01-01
Strong-interaction dynamics as probed by lepton pair production in hadronic collisions is naturally separated from kinematics by using suitably defined structure functions. In the first part of this paper, general properties of invariant structure functions and a variety of ''helicity'' structure functions for this process are studied, and their use discussed. An exact parallelism to the case of deep-inelastic lepton-hadron scattering is set up. In the second part, a series of parton-model relations between the structure functions, reflecting the basic Drell-Yan on-shell quark-antiquark annihilation picture (but independent of details of parton distributions), is derived. These relations serve the dual purposes of (i) supplementing the model-independent structure-function formalism and rendering it useful for analyzing data of limited scope initially, and (ii) providing unambiguous tests of various aspects of the underlying quark-parton model when more detailed data become available
Three body mechanisms in hadron collisions. The A = 3 system
International Nuclear Information System (INIS)
Frascaria, R.
1988-01-01
Three-body mechanisms in hadron collisions, and the role of the A = 3 system are reviewed, and the excitation functions of the proton deuteron system in interactions at energies up to 2.9 GeV are discussed. Meson productions at large angles reveal structures due to the mesonic degrees of freedom in the interaction of the proton with the deuteron, exciting n * isobars in intermediate states. Propagation in the nuclei does not seem to change the properties of these isobars. The meson double scattering mechanism provides a way to understand coherent meson production in pd capture. It is difficult to say whether this coherent process corresponds to eigenstates of the A = 3 system. The sharing of the momentum transfer between the three nucleons renders impossible the observation of high momentum components in coherent proton captures. The possible contribution of the electromagnetic probe in hadron physics with a multi GeV electron accelerator is mentioned
Proceedings of the Advanced Hadron Facility accelerator design workshop
International Nuclear Information System (INIS)
Thiessen, H.A.
1989-01-01
The International Workshop on Hadron Facility Technology was held February 22-27, 1988, at the Study Center at Los Alamos National Laboratory. The program included papers on facility plans, beam dynamics, and accelerator hardware. The parallel sessions were particularly lively with discussions of all facets of kaon factory design. The workshop provided an opportunity for communication among the staff involved in hadron facility planning from all the study groups presently active. The recommendations of the workshop include: the need to use h=1 RF in the compressor ring; the need to minimize foil hits in painting schemes for all rings; the need to consider single Coulomb scattering in injection beam los calculations; the need to study the effect of field inhomogeneity in the magnets on slow extraction for the 2.2 Tesla main ring of AHF; and agreement in principle with the design proposed for a joint Los Alamos/TRIUMF prototype main ring RF cavity
Mechanism of rising cross sections in hadron-hadron collisions
International Nuclear Information System (INIS)
Gershtejn, S.S.; Logunov, A.A.
1985-01-01
The interaction of sea constituents with each other and valence quarks, occurring in high-energy hadron collisions, is shown to explain the experimentally observed law for the rise of total cross sections, as well as the energy value at which this rise starts and the difference in these energy values for πN, KN and NN(N-barN) reactions
Stochastic evolutions and hadronization of highly excited hadronic matter
International Nuclear Information System (INIS)
Carruthers, P.
1984-01-01
Stochastic ingredients of high energy hadronic collisions are analyzed, with emphasis on multiplicity distributions. The conceptual simplicity of the k-cell negative binomial distribution is related to the evolution of probability distributions via the Fokker-Planck and related equations. The connection to underlying field theory ideas is sketched. 17 references
Hadron-hadron potentials from lattice quantum chromodynamics
International Nuclear Information System (INIS)
Rabitsch, K.
1997-10-01
Problems in nuclear physics generally involve several nucleons due to the composite structure of the atomic nucleus. To study such systems one has to solve the Schroedinger equation and therefore has to know a nucleon-nucleon potential. Experimental data and theoretical considerations indicate that nucleons consist of constituent particles, called quarks. Today, Quantum Chromodynamics (QCD) is believed to be the fundamental theory of strong interactions. Consequently, one should try to understand the nucleon-nucleon interaction from first principles of QCD. At nucleonic distances the strong coupling constant is large. Thus, a perturbative treatment of QCD low energy phenomena is not adequate. However, the formulation of QCD on a four-dimensional Euclidean lattice (lattice QCD) makes it possible to address the nonperturbative aspects of the theory. This approach has already produced valuable results. For example, the confinement of quarks in a nucleon has been demonstrated, and hadron masses have been calculated In this thesis various methods to extract the hadron-hadron interactions from first principles of lattice QCD are presented. One possibility is to consider systems of two static hadrons. A comparison of results in pure gluonic vacuum and with sea quarks is given for both the confinement and the deconfinement phase of QCD. Numerical simulations yield attractive potentials in the overlap region of the hadrons for all considered systems. In the deconfinement phase the resulting potentials are shallower reflecting the dissolution of the hadrons. A big step towards the simulation of realistic two-hadron systems on the lattice is the consideration of mesons consisting of dynamic valence quarks. This is done for the two most important fermionic discretization schemes in the pure gluonic vacuum. A calculation in coordinate space utilizing Kogut-Susskind fermions for the valence quarks yields meson-meson potentials with a long ranged interaction, an intermediate
Hadron production at RHIC: recombination of quarks
Energy Technology Data Exchange (ETDEWEB)
Fries, Rainer J [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)
2005-01-01
We discuss quark recombination applied to the hadronization of a quark gluon plasma. It has been shown that the quark recombination model can explain essential features of hadron production measured in high energy heavy ion collisions.
Detectors and luminosity for hadron colliders
International Nuclear Information System (INIS)
Diebold, R.
1983-01-01
Three types of very high energy hadron-hadron coliders are discussed in terms of the trade-off between energy and luminosity. The usable luminosity depends both on the physics under study and the rate capabilities of the detector
Physics at hadron colliders: Experimental view
International Nuclear Information System (INIS)
Siegrist, J.L.
1987-08-01
The physics of the hadron-hadron collider experiment is considered from an experimental point of view. The problems encountered in determination of how well the standard model describes collider results are discussed. 53 refs., 58 figs
Is there a hadronic Ramsauer effect
International Nuclear Information System (INIS)
Urban, M.
1980-01-01
We show that a good part of the hadronic resonances could very well not be resonances at all. We extend the principle of Ramsauer effect of atomic physics to other Physics' areas and especially to hadronic physics
Theoretical studies in hadronic and nuclear physics
International Nuclear Information System (INIS)
Griffin, J.J.; Cohen, T.D.
1993-07-01
Research in the Maryland Nuclear Theory Group focusses on problems in four basic areas of current relevance. The section on Hadrons in Nuclei reports research into the ways in which the properties of nucleons and the mesons which play a role in the nuclear force are modified in the nuclear medium. QCD sum rules supply a new insight into the decrease of the nucleon's mass in the nuclear medium. The quark condensate decreases in nuclear matter, and this is responsible for the decrease of the nucleon's mass. The section on the Structure of Hadrons reports progress in understanding the structure of the nucleon. These results cover widely different approaches -- lattice gauge calculations, QCD sum rules, quark-meson models with confinement and other hedgehog models. Progress in Relativistic Nuclear Physics is reported on electromagnetic interactions in a relativistic bound state formalism, with applications to elastic electron scattering by deuterium, and on application of a two-body quasipotential equation to calculate the spectrum of mesons formed as bound states of a quark and antiquark. A Lorentz-invariant description of the nuclear force suggests a decrease of the nucleon's mass in the nuclear medium similar to that found from QCD sum rules. Calculations of three-body bound states with simple forms of relativistic dynamics are also discussed. The section on Heavy Ion Dynamics and Related Processes describes progress on the (e + e - ) problem and heavy-on dynamics. In particular, the sharp electrons observed in β + irradiation of heavy atoms have recently been subsumed into the ''Composite Particle Scenario,'' generalizing the ''(e + e - -Puzzle'' of the pairs from heavy ion collisions to the ''Sharp Lepton Problem.''
A non-perturbative approach to jet cross-sections and a new model for hadron-hadron interactions
International Nuclear Information System (INIS)
Andersson, B.
1986-01-01
The author discusses two subjects in this work. The first is a description of a non-perturbative approach to calculate the probabilities to obtain a particular state of confined force field in a hard interaction like e/sup +/e/sup -/ annihilation. This approach has been discussed previously by the author. There are at this time many more results of the program, in particular, some rather puzzling and disturbing ones as compared to the results obtained in perturbative QCD. The second subject is a new approach to hadron-hadron inelastic scattering. A model for these interactions based upon multiple perturbative parton interactions and subsequent string-stretching and breaking has been formulated by others in earlier works
Spin as a probe of hadron structure
International Nuclear Information System (INIS)
Ali, R.
1995-01-01
In this thesis, hadron structure was explored by studying three problems. In each case some underlying hard process, or a characteristic hard momentum, yielded important physical information such as structure and fragmentation functions describing hadrons. This provided a test of QCD predictions. In the first problem, spin dependent quark structure functions were estimated for nuclei. The multipole L=2 structure function, measurable in deeply inelastic scattering of unpolarized leptons off a polarized J > 1 nuclear target, is a good indicator of exotic quark gluon components in the nucleus. I estimated this structure function for two different classes of nuclei light nuclei describable in an independent particle model approach, as well as for heavy nuclei described by slowly rotating collective variables. In the second problem, spin dependent gluonic structure functions in a transversely polarized proton were identified and the classification according to twist was discussed. I found that there were two twist three transverse spin gluonic structure functions, called herein H1(x,Q2) and H2(x,Q2). Cross section formulae were calculated for a variety of polarization states, assuming a simple effective interaction for X2 production from gluon fusion. In the third, and final problem, the emphasis shifted from spin dependent structure functions of polarised hadrons to the formulation of an effective, low energy, field theory of s wave quarkonia, constituent heavy quarks, and gluons. and radiative transitions were shown to be easily recovered. The light-cone gluon momentum distribution at very small x was calculated and shown to be uniquely determined by the non relativistic wave function. I found that the emission of low momentum gluons made this process quite sensitive to assumptions about the binding energy of heavy quarks in quarkonia. This gauge invariant theory is extend able to p-wave quarkonia where the non locality of the meson state is enhanced by the
Photon-hadron fragmentation: theoretical situation
International Nuclear Information System (INIS)
Peschanski, R.
1983-07-01
Using a selection of new experimental results models of hadronic fragmentation and their phenomenological comparison are presented. Indeed a convenient theory of hadronic fragmentation -for instance based on Q.C.D.- does not exist: low transverse momentum fragmentation involves the badly known hadronic long-range forces. Models should clarify the situation in the prospect of an eventual future theory
Heavy flavour hadron spectroscopy: An overview
Indian Academy of Sciences (India)
2014-10-31
Oct 31, 2014 ... A comprehensive overview and some of the theoretical attempts towards understanding heavy flavour hadron spectroscopy are presented. Apart from the conventional quark structure (quark, antiquarks structure for the mesons and three-quarks structure of baryons) of hadrons, multiquark hadrons the ...
Assembly of the CMS hadronic calorimeter
Maximilien Brice
2004-01-01
The hadronic calorimeter is assembled on the end-cap of the CMS detector in the assembly hall. Hadronic calorimeters measure the energy of particles that interact via the strong force, called hadrons. The detectors are made in a sandwich-like structure where these scintillator tiles are placed between metal sheets.
On the absence of multiple dips in diffraction of high energy hadrons
International Nuclear Information System (INIS)
Malecki; Michalec, M.; Pallotta, M.
1997-07-01
An unorthodox insight into the structure of the geometrical Chou-Yang model explains the experimentally observed paradox of elastic diffraction of high energy hadrons without multiple dips. It is pointed out that the shadow scattering, away from the forward peak, is governed by small values of the coupling strength
Gluonic excitations in hadronic spectroscopy
International Nuclear Information System (INIS)
Close, F.E.
1983-09-01
Theoretical expectations are described for new forms of hadronic matter containing gluons as excitable degrees of freedom. Particular attention is paid to hybrid states containing both quarks and gluons. Recent work on the spectroscopy of hybrid mesons and hybrid baryons is reviewed. Comparisons of bag model, lattice QCD and QCD sum rule predictions are made and some confrontation with data attempted. (author)
Dimensional Reduction and Hadronic Processes
International Nuclear Information System (INIS)
Signer, Adrian; Stoeckinger, Dominik
2008-01-01
We consider the application of regularization by dimensional reduction to NLO corrections of hadronic processes. The general collinear singularity structure is discussed, the origin of the regularization-scheme dependence is identified and transition rules to other regularization schemes are derived.
Energy Technology Data Exchange (ETDEWEB)
Moch, S
2008-02-15
We review the status of QCD at hadron colliders with emphasis on precision predictions and the latest theoretical developments for cross sections calculations to higher orders. We include an overview of our current information on parton distributions and discuss various Standard Model reactions such as W{sup {+-}}/Z-boson, Higgs boson or top quark production. (orig.)
International Nuclear Information System (INIS)
Moch, S.
2008-02-01
We review the status of QCD at hadron colliders with emphasis on precision predictions and the latest theoretical developments for cross sections calculations to higher orders. We include an overview of our current information on parton distributions and discuss various Standard Model reactions such as W ± /Z-boson, Higgs boson or top quark production. (orig.)
Top production at hadron colliders
Indian Academy of Sciences (India)
New results on top quark production are presented from four hadron collider experiments: CDF and D0 at the Tevatron, and ATLAS and CMS at the LHC. Cross-sections for single top and top pair production are discussed, as well as results on the top–antitop production asymmetry and searches for new physics including ...
Hadron production simulation by FLUKA
Battistoni, G; Ferrari, A; Ranft, J; Roesler, S; Sala, P R
2013-01-01
For the purposes of accelerator based neutrino experiments, the simulation of parent hadron production plays a key role. In this paper a quick overview of the main ingredients of the PEANUT event generator implemented in the FLUKA Monte Carlo code is given, together with some benchmarking examples.
A PARTNERship for hadron therapy
2008-01-01
PARTNER, the Particle Training Network for European Radiotherapy, has recently been awarded 5.6 million euros by the European Commission. The project, which is coordinated by CERN, has been set up to train researchers of the future in hadron therapy and in doing so aid the battle against cancer.
Electroweak results from hadron colliders
International Nuclear Information System (INIS)
Demarteau, Marcel
1997-01-01
A review of recent electroweak results from hadron colliders is given. Properties of the W ± and Z 0 gauge bosons using final states containing electrons and muons based on large integrated luminosities are presented. The emphasis is placed on the measurement of the mass of the W boson and the measurement of trilinear gauge boson couplings
Feigenbaum constants in hadron collisions
International Nuclear Information System (INIS)
Batunin, A.V.
1991-01-01
The coincidence is found between the law n ch (s) growth in hadron collisions for symmetric rapidity intervals and the law of growth of the number of elements in limit 2 m -cycles for one-dimensional quadratic maps when a govering parameter is varied. Fractal structure of the corresponding attractor underlies intermittency phenomenon in the multiplicity distribution of particles. 12 refs.; 1 fig
Salazar De Paula, Leandro
2015-01-01
The latest years have seen a resurrection of interest in searches for exotic states motivated by tantalising observations by Belle and CDF. Using the data collected at pp collisions at 7 and 8 TeV by the LHCb experiment we present the unambiguous new observation of exotic charmonia hadrons produced in B decays.
Energy Technology Data Exchange (ETDEWEB)
Wilkinson, III, Richard Paul [Univ. of Pennsylvania, Philadelphia, PA (United States)
1997-01-01
We present evidence for hadronic W decays in t$\\bar{t}$ → lepton + neutrino + ≥ 4 jet events using a 109 pb ^{-1} data sample of p$\\bar{p}$ collisions at √s = 1.8 TeV collected with the Collider Detector at Fermilab (CDF).
CERN's Large Hadron Collider project
Fearnley, Tom A.
1997-03-01
The paper gives a brief overview of CERN's Large Hadron Collider (LHC) project. After an outline of the physics motivation, we describe the LHC machine, interaction rates, experimental challenges, and some important physics channels to be studied. Finally we discuss the four experiments planned at the LHC: ATLAS, CMS, ALICE and LHC-B.
CERN's Large Hadron Collider project
International Nuclear Information System (INIS)
Fearnley, Tom A.
1997-01-01
The paper gives a brief overview of CERN's Large Hadron Collider (LHC) project. After an outline of the physics motivation, we describe the LHC machine, interaction rates, experimental challenges, and some important physics channels to be studied. Finally we discuss the four experiments planned at the LHC: ATLAS, CMS, ALICE and LHC-B
Charmed hadrons in nuclear medium
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
Polarization effects in hadron fragmentation
International Nuclear Information System (INIS)
Lednicky, R.
1984-01-01
Hadron polarization (spin alignment) and polarization asymmetry are discussed in terms of the quark recombination model with the spin-orbit interaction taken into account. It is shown that predictions of this model are at least in qualitative agreement with experimental data. Various polarization mechanisms in terms of this model and the possibility of their checking are also discussed
Department of Hadron Structure - Overview
International Nuclear Information System (INIS)
Eskreys, A.
2000-01-01
research program and the detector construction has been continued with the goal to be ready by 2005. Department XII is involved in the preparation of the project of the luminosity detector. TESLA is the project of the new generation high energy e + e - linear collider, planned to be built in Hamburg. Our engineers prepared the final version of electronic board which will be used in the control system of cavities for TESLA project. The analysis of the data from the two presently continued experiments (ZEUS, D0) cover the program of research ranging from the exploration of the structure of the matter in photoproduction, deep inelastic e ± p scattering and (anti)pp collisions through the searches of the exotic and rare processes (W, Z, top, leptoquarks production) to the new approach to the traditional subject like properties of the pion emission source or property of the hadronic final states. Above outsketched research has resulted in 1999 in 29 publications in the renown scientific periodicals. (author)
Czech Academy of Sciences Publication Activity Database
Aad, G.; Abajyan, T.; Abbott, B.; Böhm, Jan; Chudoba, Jiří; Hejbal, Jiří; Jakoubek, Tomáš; Kepka, Oldřich; Kupčo, Alexander; Kůs, Vlastimil; Lokajíček, Miloš; Lysák, Roman; Marčišovský, Michal; Mikeštíková, Marcela; Myška, Miroslav; Němeček, Stanislav; Roda Dos Santos, D.; Růžička, Pavel; Schovancová, Jaroslava; Šícho, Petr; Staroba, Pavel; Svatoš, Michal; Taševský, Marek; Tic, Tomáš; Vrba, Václav
2013-01-01
Roč. 88, č. 11 (2013), "112003-1"-"112003-19" ISSN 1550-7998 R&D Projects: GA MŠk(CZ) LG13009 Institutional support: RVO:68378271 Keywords : neutralino: mass * p p: scattering * gluino: lifetime * sbottom: mass * muon: background * jet: hadronic * squark * R-hadron * ATLAS * cosmic radiation Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 4.864, year: 2013
Heavy hadron spectroscopy: A quark model perspective
International Nuclear Information System (INIS)
Vijande, J.; Valcarce, A.; Caramés, T.F.; Garcilazo, H.
2013-01-01
We present recent results of hadron spectroscopy and hadron–hadron interaction from the perspective of constituent quark models. We pay special attention to the role played by higher order Fock space components in the hadron spectra and the connection of this extension with the hadron–hadron interaction. The main goal of our description is to obtain a coherent understanding of the low-energy hadron phenomenology without enforcing any particular model, to constrain its characteristics and learn about low-energy realization of the theory
Correlations in electron-positron, lepton-hadron and hadron-hadron collisions
International Nuclear Information System (INIS)
Koch, W.
1982-11-01
Recent results on two-particle correlations in rapidity space, forward-backward multiplicity correlations, charge correlations, flavour and baryon number correlations as well as Bose-Einstein correlations of identical particles are reviewed. Particular emphasis is given to the data from e + e - annihilation which serve in many respects as reference point in the interpretation of correlation phenomena observed in hadronic reactions. (orig.)
KN scattering in the nonrelativistic quark model
International Nuclear Information System (INIS)
Barnes, F.E.
1995-01-01
KN scattering is of interest as a probe of nuclear structure and, more fundamentally, as a laboratory for the study of nonresonant hadron-hadron interactions. KN is a I theoretically attractive channel because of its simplicity, having only S = 1/2, no one pion exchange contributions and no valence q anti q annihilation. It may therefore be useful for the study of short-ranged quark forces analogous to the NN repulsive core. Since there are two isospin states, comparison of two closely related amplitudes is possible. This contribution reviews the experimental status of S-wave KN scattering and related theoretical studies based on quark-gluon dynamics. The experimental low-energy S-wave phase shift is well established for I = 1, but is not yet well determined for I = 0. The ratio of I = 0 to I = 1 scattering lengths is an interesting number theoretically, and may discriminate between different scattering mechanisms. A measurement of these scattering lengths at DAPHNE would be a useful contribution to low energy hadron physics
Hadron production at LHC in dipole momentum space
International Nuclear Information System (INIS)
Basso, E. A.; Gay Ducati, M. B.; De Oliveira, E. G.
2013-01-01
The dipole color approach is the framework that considers the quark-antiquark pair scattering off the target. The rapidity evolution of color dipoles is given by the nonlinear Balitsky-Kovchegov (BK) equation, for which analytical solutions are not yet known. A good way to explore the asymptotic BK solutions is through the traveling wave method of QCD, that uses a correspondence between the BK evolution equation in momentum space and reaction-diffusion physics. Using the traveling wave based AGBS model for the dipole amplitude in momentum space, and within the k t -factorization formalism, we describe the LHC data on single inclusive hadron yield for p–p collisions.
Some results on excited hadrons in 2-flavor QCD
Engel, G.; Lang, C. B.; Limmer, M.; Mohler, D.; Schafer, A.
Results of hadron spectroscopy with two dynamical mass-degenerate chirally improved quarks are presented. Three ensembles with pion masses of 322(5), 470(4) and 525(7) MeV, lattices of size 16^3 \\times 32, and lattice spacings close to 0.15 fm are investigated. We discuss the possible appearance of scattering states, considering masses and eigenvectors. Partially quenched results in the scalar channel suggest the presence of a 2-particle state, however, in most channels we cannot identify them. Where available, we compare to results from quenched simulations using the same action.
Analytical theory for the nuclear level shift of hadronic atoms
International Nuclear Information System (INIS)
Kudryavtsev, A.E.; Lisin, V.I.; Popov, V.S.
1982-01-01
The spectrum problem in the Coulomb potential distorted at small distances is considered. Nuclear shifts of 3-levels in p anti p and Σ - p atoms are calculated. The probabilities of radiative transitions from p-states to the shifted s-states in hadronic atom are also given. It is shown that the reconstruction of atomic levels switches to oscillation regime when absorption increases. The limits of applicability of the perturbation theory in terms of the scattering length for different values of absorption is discussed. An exactly solvable model, Coulomb plus Yamaguchi potential, is considered
Parity violating asymmetries in polarized electron scattering
International Nuclear Information System (INIS)
Derman, E.; Marciano, W.J.
1979-01-01
We discuss parity violating asymmetries between the scattering of right and left-handed electrons on a variety of targets. Implications for gauge theories from recent SLAC results on deep-inelastic electron-deuterium and electron-proton scattering are examined. A derivation of the asymmetry for electron-electron scattering is given, its advantages are pointed out, and the feasibility of such a measurement is discussed. Other proposed or contemplated asymmetry experiments are reviewed and the necessity of including the Collins-Wilczek-Zee hadronic axial isoscalar current contribution in asymmetry predictions is noted
Hadronic photon-photon interactions at high energies
International Nuclear Information System (INIS)
Engel, R.; Siegen Univ.; Ranft, J.
1996-01-01
Photon-photon collisions are investigated in the framework of the two-component Dual Parton Model. The model contains contributions from direct, resolved soft and resolved hard interactions. All free parameters of the model are determined in fits to hadron-hadron and photon-hadron cross section data. The model is shown to agree well to hadron production data from hadron-hadron and photon-hadron collisions. The multiparticle production in hadron-hadron, photon-hadron and photon-photon collisions as predicted by the model is compared. Strong differences are only found as function of the transverse momentum variable. (author)
International Nuclear Information System (INIS)
Golovanova, N.F.; Ibraeva, E.T.; Neudatchin, V.G.
1978-01-01
Different multiplicities and their interference in hadron scattering have been investigated on the basis of a new dynamic approach to quasi-elastic knock-out of nucleon clusters by fast hadrons from light nuclei. It is shown that in the region of momentum transfer values p, where scattering multiplicities less than b are predominant, the effective numbers and form factors determined in Refs. 1) -- 3) no longer act as pure structural nuclear factors (b means the number of nucleons in the knocked-out cluster). These characteristics are significantly dependent on the process dynamics. Only in the region of values p, where the maximum hadron scattering multiplicity b is realized, the effective numbers and form factors do assume the purely structural meaning. (auth.)
Fermionic NNLO contributions to Bhabha scattering
International Nuclear Information System (INIS)
Actis, S.; Riemann, T.; Czakon, M.; Uniwersytet Slaski, Katowice; Gluza, J.
2007-10-01
We derive the two-loop corrections to Bhabha scattering from heavy fermions using dispersion relations. The double-box contributions are expressed by three kernel functions. Convoluting the perturbative kernels with fermionic threshold functions or with hadronic data allows to determine numerical results for small electron mass m e , combined with arbitrary values of the fermion mass m f in the loop, m 2 e 2 f , or with hadronic insertions. We present numerical results for m f =m μ , m τ ,m top at typical small- and large-angle kinematics ranging from 1 GeV to 500 GeV. (orig.)
Radiative corrections to deep inelastic muon scattering
International Nuclear Information System (INIS)
Akhundov, A.A.; Bardin, D.Yu.; Lohman, W.
1986-01-01
A summary is given of the most recent results for the calculaion of radiative corrections to deep inelastic muon-nucleon scattering. Contributions from leptonic electromagnetic processes up to the order a 4 , vacuum polarization by leptons and hadrons, hadronic electromagnetic processes approximately a 3 and γZ interference have been taken into account. The dependence of the individual contributions on kinematical variables is studied. Contributions, not considered in earlier calculations of radiative corrections, reach in certain kinematical regions several per cent at energies above 100 GeV
Heavy flavor at the large hadron collider in a strong coupling approach
Energy Technology Data Exchange (ETDEWEB)
He, Min [Department of Applied Physics, Nanjing University of Science and Technology, Nanjing 210094 (China); Fries, Rainer J.; Rapp, Ralf [Cyclotron Institute and Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843-3366 (United States)
2014-07-30
Employing nonperturbative transport coefficients for heavy-flavor (HF) diffusion through quark–gluon plasma (QGP), hadronization and hadronic matter, we compute D- and B-meson observables in Pb+Pb (√(s)=2.76 TeV) collisions at the LHC. Elastic heavy-quark scattering in the QGP is evaluated within a thermodynamic T-matrix approach, generating resonances close to the critical temperature which are utilized for recombination into D and B mesons, followed by hadronic diffusion using effective hadronic scattering amplitudes. The transport coefficients are implemented via Fokker–Planck Langevin dynamics within hydrodynamic simulations of the bulk medium in nuclear collisions. The hydro expansion is quantitatively constrained by transverse-momentum spectra and elliptic flow of light hadrons. Our approach thus incorporates the paradigm of a strongly coupled medium in both bulk and HF dynamics throughout the thermal evolution of the system. At low and intermediate p{sub T}, HF observables at LHC are reasonably well accounted for, while discrepancies at high p{sub T} are indicative for radiative mechanisms not included in our approach.
Supersymmetry across the Hadronic Spectrum
Directory of Open Access Journals (Sweden)
Hans Günter Dosch
2017-01-01
Full Text Available Semiclassical light-front bound-state equations for hadrons are presented and compared with experiment. The essential dynamical feature is the holographic approach; that is, the hadronic equations in four-dimensional Minkowski space are derived as holograms of classical equations in a 5-dimensional anti-de Sitter space. The form of the equations is constrained by the imposed superconformal algebra, which fixes the form of the light-front potential. If conformal symmetry is strongly broken by heavy quark masses, the combination of supersymmetry and the classical action in the 5-dimensional space still fixes the form of the potential. By heavy quark symmetry, the strength of the potential is related to the heavy quark mass. The contribution is based on several recent papers in collaboration with Stan Brodsky and Guy de Téramond.
Hadron therapy information sharing prototype
Roman, Faustin Laurentiu; Kanellopoulos, Vassiliki; Amoros, Gabriel; Davies, Jim; Dosanjh, Manjit; Jena, Raj; Kirkby, Norman; Peach, Ken; Salt, Jose
2013-01-01
The European PARTNER project developed a prototypical system for sharing hadron therapy data. This system allows doctors and patients to record and report treatment-related events during and after hadron therapy. It presents doctors and statisticians with an integrated view of adverse events across institutions, using open-source components for data federation, semantics, and analysis. There is a particular emphasis upon semantic consistency, achieved through intelligent, annotated form designs. The system as presented is ready for use in a clinical setting, and amenable to further customization. The essential contribution of the work reported here lies in the novel data integration and reporting methods, as well as the approach to software sustainability achieved through the use of community-supported open-source components.
Quantum groups in hadron phenomenology
International Nuclear Information System (INIS)
Gavrilik, A.M.
1997-01-01
We show that application of quantum unitary groups, in place of ordinary flavor SU(n f ), to such static aspects of hadron phenomenology as hadron masses and mass formulas is indeed fruitful. So-called q-deformed mass formulas are given for octet baryons 1/2 + and decuplet baryons 3/2 + , as well as for the case of vector mesons 1 - involving heavy flavors. For deformation parameter q, rigid fixation of values is used. New mass sum rules of remarkable accuracy are presented. As shown in decuplet case, the approach accounts for effects highly nonlinear in SU(3)-breaking. Topological implication (possible connection with knots) for singlet vector mesons and the relation q ↔ Θ c (Cabibbo angle) in case of baryons are considered
Hadron therapy physics and simulations
d’Ávila Nunes, Marcos
2014-01-01
This brief provides an in-depth overview of the physics of hadron therapy, ranging from the history to the latest contributions to the subject. It covers the mechanisms of protons and carbon ions at the molecular level (DNA breaks and proteins 53BP1 and RPA), the physics and mathematics of accelerators (Cyclotron and Synchrotron), microdosimetry measurements (with new results so far achieved), and Monte Carlo simulations in hadron therapy using FLUKA (CERN) and MCHIT (FIAS) software. The text also includes information about proton therapy centers and carbon ion centers (PTCOG), as well as a comparison and discussion of both techniques in treatment planning and radiation monitoring. This brief is suitable for newcomers to medical physics as well as seasoned specialists in radiation oncology.
New possibilities for exotic hadrons
International Nuclear Information System (INIS)
Lipkin, H.J.
1987-01-01
New theoretical ideas and experimental evidence for exotic hadrons are presented. A new exciting candidate is an anticharmed baryon; i.e., a bound state of a nucleon and an F (now called D 3 ). New experimental evidence for four-quark exotic mesons presented at this conference is discussed. The confusion in the E-iota region and the pseudoscalar spectrum still await further experimental clarification
Heavy leptons at hadron colliders
International Nuclear Information System (INIS)
Ohnemus, J.E.
1987-01-01
The recent advent of high energy hadron colliders capable of producing weak bosons has opened new vistas for particle physics research, including the search for a possible fourth generation heavy charged lepton, which is the primary topic of the thesis. Signals for identifying a new heavy lepton have been calculated and compared to Standard Model backgrounds. Results are presented for signals at the CERN collider, the Fermilab collider, and the proposed Superconducting Supercollider
Hadron Structure '87. Volume 14
International Nuclear Information System (INIS)
Krupa, D.
1988-01-01
Out of the 21 papers and 41 short communications presented at the conference, the proceedings contain the full texts of 12 papers and 35 short communications. All these contributions have been inputted to INIS. The topics covered include nonperturbative calculations in the field theory, in QCD in particular; particle production in hadron-nucleus and nucleus-nucleus collisions and the quark-gluon plasma; and recent experimental results in the field. (A.K.)
Hadrons, the simplest gentilionic systems
International Nuclear Information System (INIS)
Cattani, M.S.D.
1987-11-01
Basic quantum mechanical properties of systems constituted by two and three gentileons are deduced in this paper. By using Pauli's theorem and symmetry properties of the intermediate states it is shown that, in some cases, gentileons must have half-odd-integral spin. As an immediate and natural result of our theoretical analysis, we show how fundamental observed properties of composed hadrons can be predicted from first principles assuming quarks as spin 1/2 gentileons. (author) [pt
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.
Experiments at future hadron colliders
International Nuclear Information System (INIS)
Paige, F.E.
1991-01-01
This report summarizes signatures and backgrounds for processes in high-energy hadronic collisions, particularly at the SSC. It includes both signatures for new particles -- t quarks, Higgs bosons, new Ζ' bosons, supersymmetric particles, and technicolor particles -- and other experiments which might be done. It is based on the 1990 Snowmass Workshop and on work contained in the Expressions of Interest submitted to the SSC. 46 refs., 19 figs., 1 tab