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1. NA61/SHINE facility at the CERN SPS: beams and detector system

Author

Abgrall, N, Andreeva, O, Aduszkiewicz, A, Ali, Y, Anticic, T, Antoniou, N, Baatar, B, Bay, F, Blondel, A, Blumer, J, Bogomilov, M, Bogusz, M, Bravar, A, Brzychczyk, J, Bunyatov, SA, Christakoglou, P, Cirkovic, M, Czopowicz, T, Davis, N, Debieux, S, Dembinski, H, Diakonos, F, Di Luise, S, Dominik, W, Drozhzhova, T, Dumarchez, J, Dynowski, K, Engel, R, Efthymiopoulos, I, Ereditato, A, Fabich, A, Feofilov, GA, Fodor, Z, Fulop, A, Gaździcki, M, Golubeva, M, Grebieszkow, K, Grzeszczuk, A, Guber, F, Haesler, A, Hasegawa, T, Hierholzer, M, Idczak, R, Igolkin, S, Ivashkin, A, Jokovic, D, Kadija, K, Kapoyannis, A, Kaptur, E, Kielczewska, D, Kirejczyk, M, Kisiel, J, Kiss, T, Kleinfelder, S, Kobayashi, T, Kolesnikov, VI, Kolev, D, Kondratiev, VP, Korzenev, A, Koversarski, P, Kowalski, S, Krasnoperov, A, Kurepin, A, Larsen, D, Laszlo, A, Lyubushkin, VV, Maćkowiak-Pawłowska, M, Majka, Z, Maksiak, B, Malakhov, AI, Maletic, D, Manglunki, D, Manic, D, Marchionni, A, Marcinek, A, Marin, V, Marton, K, Mathes, H-J, Matulewicz, T, Matveev, V, Melkumov, GL, Messina, M, Mrówczyński, St, Murphy, S, Nakadaira, T, Nirkko, M, Nishikawa, K, Palczewski, T, Palla, G, Panagiotou, AD, Paul, T, Peryt, W, Petukhov, O, Pistillo, C, Płaneta, R, Pluta, J, Popov, BA, Posiadala, M, Puławski, S, and Puzovic, J

Subjects
Particle identification methods, Time projection chambers, Instrumentation for radioactive beams (fragmentation devices, fragment and isotope, separators incl. ISOL, isobar separators, ion and atom traps, weak-beam diagnostics, radioactive-beam ion sources), Trigger detectors, physics.ins-det, nucl-ex, 81V36, Physical Sciences, Engineering, Nuclear & Particles Physics
Abstract

NA61/SHINE (SPS Heavy Ion and Neutrino Experiment) is a multi-purpose experimental facility to study hadron production in hadron-proton, hadron-nucleus and nucleus-nucleus collisions at the CERN Super Proton Synchrotron. It recorded the first physics data with hadron beams in 2009 and with ion beams (secondary 7Be beams) in 2011. NA61/SHINE has greatly profited from the long development of the CERN proton and ion sources and the accelerator chain as well as the H2 beamline of the CERN North Area. The latter has recently been modified to also serve as a fragment separator as needed to produce the Be beams for NA61/SHINE. Numerous components of the NA61/SHINE set-up were inherited from its predecessors, in particular, the last one, the NA49 experiment. Important new detectors and upgrades of the legacy equipment were introduced by the NA61/SHINE Collaboration. This paper describes the state of the NA61/SHINE facility - the beams and the detector system - before the CERN Long Shutdown I, which started in March 2013. © CERN 2014 for the benefit of the NA61/SHINE collaboration..

Published
2014

2. Measurement of negatively charged pion spectra in inelastic p plus p interactions at p(lab)=20, 31, 40, 80 and 158 GeV/c

Author

Abgrall, N, Aduszkiewicz, A, Ali, Y, Anticic, T, Antoniou, N, Baatar, B, Bay, F, Blondel, A, Blumer, J, Bogomilov, M, Bravar, A, Brzychczyk, J, Bunyatov, SA, Busygina, O, Christakoglou, P, Czopowicz, T, Davis, N, Debieux, S, Dembinski, H, Diakonos, F, Di Luise, S, Dominik, W, Drozhzhova, T, Dumarchez, J, Dynowski, K, Engel, R, Ereditato, A, Feofilov, GA, Fodor, Z, Fulop, A, Gazdzicki, M, Golubeva, M, Grebieszkow, K, Grzeszczuk, A, Guber, F, Haesler, A, Hasegawa, T, Hierholzer, M, Idczak, R, Igolkin, S, Ivashkin, A, Jokovic, D, Kadija, K, Kapoyannis, A, Kaptur, E, Kielczewska, D, Kirejczyk, M, Kisiel, J, Kiss, T, Kleinfelder, S, Kobayashi, T, Kolesnikov, VI, Kolev, D, Kondratiev, VP, Korzenev, A, Kovesarki, P, Kowalski, S, Krasnoperov, A, Kurepin, A, Larsen, D, Laszlo, A, Lyubushkin, VV, Mackowiak-Pawlowska, M, Majka, Z, Maksiak, B, Malakhov, AI, Manic, D, Marcinek, A, Marin, V, Marton, K, Mathes, H-J, Matulewicz, T, Matveev, V, Melkumov, GL, Mrowczynski, St, Murphy, S, Nakadaira, T, Nirkko, M, Nishikawa, K, Palczewski, T, Palla, G, Panagiotou, AD, Paul, T, Pistillo, C, Peryt, W, Petukhov, O, Planeta, R, Pluta, J, Popov, BA, Posiadala, M, Pulawski, S, Puzovic, J, Rauch, W, Ravonel, M, Redij, A, Renfordt, R, Robert, A, Roehrich, D, Rondio, E, and Roth, M

Subjects
hep-ex, nucl-ex, Nuclear & Particles Physics, Quantum Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract

We present experimental results on inclusive spectra and mean multiplicitiesof negatively charged pions produced in inelastic p+p interactions at incidentprojectile momenta of 20, 31, 40, 80 and 158 GeV/c ($\sqrt{s} = $ 6.3, 7.7,8.8, 12.3 and 17.3 GeV, respectively). The measurements were performed usingthe large acceptance NA61/SHINE hadron spectrometer at the CERN Super ProtonSynchrotron. Two-dimensional spectra are determined in terms of rapidity and transversemomentum. Their properties such as the width of rapidity distributions and theinverse slope parameter of transverse mass spectra are extracted and theircollision energy dependences are presented. The results on inelastic p+pinteractions are compared with the corresponding data on central Pb+Pbcollisions measured by the NA49 experiment at the CERN SPS. The results presented in this paper are part of the NA61/SHINE ion programdevoted to the study of the properties of the onset of deconfinement and searchfor the critical point of strongly interacting matter. They are required forinterpretation of results on nucleus-nucleus and proton-nucleus collisions.

Published
2014

3. Measurement of negatively charged pion spectra in inelastic p+p interactions at plab= 20, 31, 40, 80 and 158 GeV/c

Author

Abgrall, N, Aduszkiewicz, A, Ali, Y, Anticic, T, Antoniou, N, Baatar, B, Bay, F, Blondel, A, Blumer, J, Bogomilov, M, Bravar, A, Brzychczyk, J, Bunyatov, SA, Busygina, O, Christakoglou, P, Czopowicz, T, Davis, N, Debieux, S, Dembinski, H, Diakonos, F, Luise, S Di, Dominik, W, Drozhzhova, T, Dumarchez, J, Dynowski, K, Engel, R, Ereditato, A, Feofilov, GA, Fodor, Z, Fulop, A, Gaździcki, M, Golubeva, M, Grebieszkow, K, Grzeszczuk, A, Guber, F, Haesler, A, Hasegawa, T, Hierholzer, M, Idczak, R, Igolkin, S, Ivashkin, A, Joković, D, Kadija, K, Kapoyannis, A, Kaptur, E, Kiełczewska, D, Kirejczyk, M, Kisiel, J, Kiss, T, Kleinfelder, S, Kobayashi, T, Kolesnikov, VI, Kolev, D, Kondratiev, VP, Korzenev, A, Kovesarki, P, Kowalski, S, Krasnoperov, A, Kurepin, A, Larsen, D, László, A, Lyubushkin, VV, Maćkowiak-Pawłowska, M, Majka, Z, Maksiak, B, Malakhov, AI, Manić, D, Marcinek, A, Marin, V, Marton, K, Mathes, H-J, Matulewicz, T, Matveev, V, Melkumov, GL, Mrówczyński, St, Murphy, S, Nakadaira, T, Nirkko, M, Nishikawa, K, Palczewski, T, Palla, G, Panagiotou, AD, Paul, T, Pistillo, C, Peryt, W, Petukhov, O, Płaneta, R, Pluta, J, Popov, BA, Posiadała, M, Puławski, S, Puzović, J, Rauch, W, Ravonel, M, Redij, A, Renfordt, R, Robert, A, Röhrich, D, Rondio, E, and Roth, M

Subjects
hep-ex, nucl-ex, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Quantum Physics, Nuclear & Particles Physics
Abstract

We present experimental results on inclusive spectra and mean multiplicitiesof negatively charged pions produced in inelastic p+p interactions at incidentprojectile momenta of 20, 31, 40, 80 and 158 GeV/c ($\sqrt{s} = $ 6.3, 7.7,8.8, 12.3 and 17.3 GeV, respectively). The measurements were performed usingthe large acceptance NA61/SHINE hadron spectrometer at the CERN Super ProtonSynchrotron. Two-dimensional spectra are determined in terms of rapidity and transversemomentum. Their properties such as the width of rapidity distributions and theinverse slope parameter of transverse mass spectra are extracted and theircollision energy dependences are presented. The results on inelastic p+pinteractions are compared with the corresponding data on central Pb+Pbcollisions measured by the NA49 experiment at the CERN SPS. The results presented in this paper are part of the NA61/SHINE ion programdevoted to the study of the properties of the onset of deconfinement and searchfor the critical point of strongly interacting matter. They are required forinterpretation of results on nucleus-nucleus and proton-nucleus collisions.

Published
2014

4. Measurements of production properties of K S 0 mesons and Λ hyperons in proton-carbon interactions at 31 GeV/ c

Author

Abgrall, N, Aduszkiewicz, A, Ali, Y, Anticic, T, Antoniou, N, Argyriades, J, Baatar, B, Blondel, A, Blumer, J, Bogomilov, M, Bravar, A, Brooks, W, Brzychczyk, J, Bunyatov, SA, Busygina, O, Christakoglou, P, Czopowicz, T, Davis, N, Debieux, S, Dembinski, H, Diakonos, F, Di Luise, S, Dominik, W, Drozhzhova, T, Dumarchez, J, Dynowski, K, Engel, R, Ereditato, A, Esposito, L, Feofilov, GA, Fodor, Z, Fulop, A, Gaådzicki, M, Golubeva, M, Grebieszkow, K, Grzeszczuk, A, Guber, F, Hakobyan, H, Haesler, A, Hasegawa, T, Hierholzer, M, Idczak, R, Igolkin, S, Ivanov, Y, Ivashkin, A, Jokovic, D, Kadija, K, Kapoyannis, A, Kaptur, E, Kielczewska, D, Kikola, D, Kirejczyk, M, Kisiel, J, Kiss, T, Kleinfelder, S, Kobayashi, T, Kolesnikov, VI, Kolev, D, Kondratiev, VP, Korzenev, A, Kovesarki, P, Kowalski, S, Krasnoperov, A, Kuleshov, S, Kurepin, A, Larsen, D, Laszlo, A, Lyubushkin, VV, Mackowiak-Pawlowska, M, Majka, Z, Maksiak, B, Malakhov, AI, Maletic, D, Manic, D, Marchionni, A, Marcinek, A, Marin, V, Marton, K, Mathes, HJ, Matulewicz, T, Matveev, V, Melkumov, GL, Mrówczyński, S, Murphy, S, Nakadaira, T, Nirkko, M, Nishikawa, K, Palczewski, T, Palla, G, Panagiotou, AD, Paul, T, Peryt, W, Pistillo, C, Redij, A, Petukhov, O, Planeta, R, Pluta, J, Popov, BA, Posiadała, M, and Puławski, S

Subjects
physics.acc-ph, nucl-ex, Nuclear & Particles Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract

Spectra of KS0 mesons and Λ hyperons were measured in p + C interactions at 31 GeV/c with the large acceptance NA61/SHINE spectrometer at the CERN SPS. The data were collected with an isotropic graphite target with a thickness of 4% of a nuclear interaction length. Interaction cross sections, charged pion spectra, and charged kaon spectra were previously measured using the same data set. Results on KS0 and Λ production in p + C interactions serve as a reference for the understanding of the enhancement of strangeness production in nucleus-nucleus collisions. Moreover, they provide important input for the improvement of neutrino flux predictions for the T2K long baseline neutrino oscillation experiment in Japan. Inclusive production cross sections for KS0 and Λ are presented as a function of laboratory momentum in intervals of the laboratory polar angle covering the range from 0 up to 240 mrad. The results are compared with predictions of several hadron production models. The KS0 mean multiplicity in production processes 〈nKS0〉 and the inclusive cross section for KS0 production σKS0 were measured and amount to 0.127 ± 0.005 (stat) ± 0.022 (sys) and 29.0 ± 1.6 (stat) ± 5.0 (sys) mb, respectively. © 2014 American Physical Society.

Published
2014

5. Measurements of production properties of KS0 mesons and Λ hyperons in proton-carbon interactions at 31 GeV/c

Author

Abgrall, N, Aduszkiewicz, A, Ali, Y, Anticic, T, Antoniou, N, Argyriades, J, Baatar, B, Blondel, A, Blumer, J, Bogomilov, M, Bravar, A, Brooks, W, Brzychczyk, J, Bunyatov, SA, Busygina, O, Christakoglou, P, Czopowicz, T, Davis, N, Debieux, S, Dembinski, H, Diakonos, F, Di Luise, S, Dominik, W, Drozhzhova, T, Dumarchez, J, Dynowski, K, Engel, R, Ereditato, A, Esposito, L, Feofilov, GA, Fodor, Z, Fulop, A, Gaździcki, M, Golubeva, M, Grebieszkow, K, Grzeszczuk, A, Guber, F, Hakobyan, H, Haesler, A, Hasegawa, T, Hierholzer, M, Idczak, R, Igolkin, S, Ivanov, Y, Ivashkin, A, Jokovic, D, Kadija, K, Kapoyannis, A, Kaptur, E, Kielczewska, D, Kikola, D, Kirejczyk, M, Kisiel, J, Kiss, T, Kleinfelder, S, Kobayashi, T, Kolesnikov, VI, Kolev, D, Kondratiev, VP, Korzenev, A, Kovesarki, P, Kowalski, S, Krasnoperov, A, Kuleshov, S, Kurepin, A, Larsen, D, Laszlo, A, Lyubushkin, VV, Mackowiak-Pawlowska, M, Majka, Z, Maksiak, B, Malakhov, AI, Maletic, D, Manic, D, Marchionni, A, Marcinek, A, Marin, V, Marton, K, Mathes, H-J, Matulewicz, T, Matveev, V, Melkumov, GL, Mrówczyński, St, Murphy, S, Nakadaira, T, Nirkko, M, Nishikawa, K, Palczewski, T, Palla, G, Panagiotou, AD, Paul, T, Peryt, W, Pistillo, C, Redij, A, Petukhov, O, Planeta, R, Pluta, J, Popov, BA, Posiadała, M, and Puławski, S

Subjects
physics.acc-ph, nucl-ex, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics
Abstract

Spectra of KS0 mesons and Λ hyperons were measured in p + C interactions at 31 GeV/c with the large acceptance NA61/SHINE spectrometer at the CERN SPS. The data were collected with an isotropic graphite target with a thickness of 4% of a nuclear interaction length. Interaction cross sections, charged pion spectra, and charged kaon spectra were previously measured using the same data set. Results on KS0 and Λ production in p + C interactions serve as a reference for the understanding of the enhancement of strangeness production in nucleus-nucleus collisions. Moreover, they provide important input for the improvement of neutrino flux predictions for the T2K long baseline neutrino oscillation experiment in Japan. Inclusive production cross sections for KS0 and Λ are presented as a function of laboratory momentum in intervals of the laboratory polar angle covering the range from 0 up to 240 mrad. The results are compared with predictions of several hadron production models. The KS0 mean multiplicity in production processes 〈nKS0〉 and the inclusive cross section for KS0 production σKS0 were measured and amount to 0.127 ± 0.005 (stat) ± 0.022 (sys) and 29.0 ± 1.6 (stat) ± 5.0 (sys) mb, respectively. © 2014 American Physical Society.

Published
2014

6. Hadronic expansion dynamics in central Pb+Pb collisions at 158 GeV per nucleon

Author

Appelshäuser, H, Bächler, J, Bailey, SJ, Barnby, LS, Bartke, J, Barton, RA, Białkowska, H, Billmeier, A, Blyth, CO, Bock, R, Bormann, C, Brady, FP, Brockmann, R, Brun, R, Bunčić, P, Caines, HL, Cebra, D, Cooper, GE, Cramer, JG, Csato, P, Dunn, J, Eckardt, V, Eckhardt, F, Ferguson, MI, Ferenc, D, Fischer, HG, Flierl, D, Fodor, Z, Foka, P, Freund, P, Friese, V, Fuchs, M, Gabler, F, Gal, J, Gaździcki, M, Gladysz, E, Grebieszkow, J, Günther, J, Harris, JW, Hegyi, S, Henkel, T, Hill, LA, Huang, I, Hümmler, H, Igo, G, Irmscher, D, Jacobs, P, Jones, PG, Kadija, K, Kolesnikov, VI, Kowalski, M, Lasiuk, B, Lévai, P, Malakhov, AI, Margetis, S, Markert, C, Melkumov, GL, Mock, A, Molnár, J, Nelson, JM, Oldenburg, M, Odyniec, G, Palla, G, Panagiotou, AD, Petridis, A, Piper, A, Porter, RJ, Poskanzer, AM, Poziombka, S, Prindle, DJ, Pühlhofer, F, Rauch, W, Reid, JG, Renfordt, R, Retyk, W, Ritter, HG, Röhrich, D, Roland, C, Roland, G, Rudolph, H, Rybicki, A, Sandoval, A, Sann, H, Semenov, AY, Schäfer, E, Schmischke, D, Schmitz, N, Schönfelder, S, Seyboth, P, Seyerlein, J, Sikler, F, Skrzypczak, E, Squier, GTA, Stock, R, Ströbele, H, Struck, C, Szentpetery, I, Sziklai, J, Toy, M, and Trainor, TA

Subjects
Nuclear & Particles Physics, Quantum Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract

Two-particle correlation functions of negative hadrons over wide phase space, and transverse mass spectra of negative hadrons and deuterons near mid-rapidity have been measured in central Pb+Pb collisions at 158 GeV per nucleon by the NA49 experiment at the CERN SPS. A novel Coulomb correction procedure for the negative two-particle correlations is employed making use of the measured oppositely charged particle correlation. Within an expanding source scenario these results are used to extract the dynamic characteristics of the hadronic source, resolving the ambiguities between the temperature and transverse expansion velocity of the source, that are unavoidable when single and two particle spectra are analysed separately. The source shape, the total duration of the source expansion, the duration of particle emission, the freeze-out temperature and the longitudinal and transverse expansion velocities are deduced.

Published
1998

7. Charged particle production in proton-, deuteron-, oxygen- and sulphur-nucleus collisions at 200 GeV per nucleon

Author

Alber, T, Appelshäuser, H, Bächler, J, Bartke, J, Białkowska, H, Bloomer, MA, Bock, R, Braithwaite, WJ, Brinkmann, D, Brockmann, R, Bunčić, P, Chan, P, Cramer, JG, Cramer, PB, Derado, I, Eberlein, B, Eckardt, V, Eschke, J, Favuzzi, C, Ferenc, D, Fleischmann, B, Foka, P, Freund, P, Fuchs, M, Gaździcki, M, Gładysz, E, Grebieszkow, J, Günther, J, Harris, JW, Hoffmann, M, Jacobs, P, Kabana, S, Kadija, K, Keidel, R, Kowalski, M, Kühmichel, A, Lave, F, Lee, JY, Ljubičić, A, Margetis, S, Mitchell, JT, Morse, R, Nappi, E, Odyniec, G, Paić, G, Panagiotou, AD, Petridis, A, Piper, A, Posa, F, Poskanzer, AM, Pühlhofer, F, Rauch, W, Renfordt, R, Retyk, W, Röhrich, D, Roland, G, Rothard, H, Runge, K, Sandoval, A, Schmitz, N, Schmoetten, E, Sendelbach, R, Seyboth, P, Seyerlein, J, Skrzypczak, E, Spinelli, P, Stock, R, Ströbele, H, Teitelbaum, L, Tonse, S, Trainor, TA, Vasileiadis, G, Vassiliou, M, Vesztergombi, G, Vranic, D, Wenig, S, Wosiek, B, and Zhu, X

Subjects
Nuclear & Particles Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Quantum Physics
Abstract

The transverse momentum and rapidity distributions of net protons and negatively charged hadrons have been measured for minimum bias proton-nucleus and deuteron-gold interactions, as well as central oxygen-gold and sulphur-nucleus collisions at 200 GeV per nucleon. The rapidity density of net protons at midrapidity in central nucleus-nucleus collisions increases both with target mass for sulphur projectiles and with the projectile mass for a gold target. The shape of the rapidity distributions of net protons forward of midrapidity for d+Au and central S+Au collisions is similar. The average rapidity loss is larger than 2 units of rapidity for reactions with the gold target. The transverse momentum spectra of net protons for all reactions can be described by a thermal distribution with 'temperatures' between 145±11 MeV (p+S interactions) and 244±43 MeV (central S+Au collisions). The multiplicity of negatively charged hadrons increases with the mass of the colliding system. The shape of the transverse momentum spectra of negatively charged hadrons changes from minimum bias p+p and p+S interactions to p+Au and central nucleus-nucleus collisions. The mean transverse momentum is almost constant in the vicinity of midrapidity and shows little variation with the target and projectile masses. The average number of produced negatively charged hadrons per participant baryon increases slightly from p+p, p+A to central S+S,Ag collisions.

Published
1998

8. Upper limit of D-0 production in central Pb-Pb collisions at 158A GeV

Author

Alt, C Anticic, T Baatar, B Barna, D Bartke, J and Betev, L Bialkowska, H Blume, C Boimska, B Botje, M and Bracinik, J Bramm, R Buncic, P Cerny, V Christakoglou, P and Chvala, O Cramer, JG Csato, P Dinkelaker, P Eckardt, V Flierl, D Fodor, Z Foka, P Friese, V Gal, J and Gazdzicki, M Genchev, V Georgopoulos, G Gladysz, E and Grebieszkow, K Hegyi, S Hohne, C Kadija, K Karev, A and Kliemant, M Kniege, S Kolesnikov, VI Kornas, E Korus, R and Kowalski, M Kraus, I Kreps, M van Leeuwen, M Levai, P Litov, L Lungwitz, B Makariev, M Malakhov, AI and Markert, C Mateev, M Melkumov, GL Mischke, A Mitrovski, M Molnar, J Mrowczynski, S Nicolic, V Palla, G and Panagiotou, AD Panayotov, D Petridis, A Pikna, M and Prindle, D Puhlhofer, F Renfordt, R Roland, C Roland, G and Rybczynski, M Rybicki, A Sandoval, A Schmitz, N and Schuster, T Seyboth, P Sikler, F Sitar, B Skrzypczak, E and Stefanek, G Stock, R Strobele, H Susa, T and Szentpetery, I Sziklai, J Szymanski, P Trubnikov, V and Varga, D Vassiliou, M Veres, GI Vesztergombi, G Vranic, D Wetzler, A Wlodarczyk, Z Yoo, IK Zimanyi, J NA49 Collaborat

Abstract

Results are presented from a search for the decays D-0-> K(-)pi(+) and (D) over bar (0)-> K(+)pi(-) in a sample of 3.8x10(6) central Pb-Pb events collected with a beam energy of 158A GeV by NA49 at the CERN SPS. No signal is observed. An upper limit on D-0 production is derived and compared to predictions from several models.

Published
2006

9. Energy and centrality dependence of (p)over-bar and p production and the (Lambda)over-bar/(p)over-bar ratio in Pb plus Pb collisions between 20A GeV and 158A GeV

Author

Alt, C Anticic, T Baatar, B Barna, D Bartke, J and Betev, L Bialkowska, H Blume, C Boimska, B Botje, M and Bracinik, J Bramm, R Buncic, P Cerny, V Christakoglou, P and Chvala, O Cramer, JG Csato, P Dinkelaker, P Eckardt, V Flierl, D Fodor, Z Foka, P Friese, V Gal, J and Gazdzicki, M Genchev, V Georgopoulos, G Gladysz, E and Grebieszkow, K Hegyi, S Hohne, C Kadija, K Karev, A and Kliemant, M Kniege, S Kolesnikov, VI Kornas, E Korus, R and Kowalski, M Kraus, I Kreps, M Laslo, A van Leeuwen, M Levai, P Litov, L Lungwitz, B Makariev, M and Malakhov, AI Mateev, M Melkumov, GL Mischke, A and Mitrovski, M Molnar, J Mrowczynski, S Nicolic, V Palla, G Panagiotou, AD Panayotov, D Petridis, A Pikna, M and Prindle, D Puhlhofer, F Renfordt, R Roland, C Roland, G and Rybczynski, M Rybicki, A Sandoval, A Schmitz, N and Schuster, T Seyboth, P Sikler, F Sitar, B Skrzypczak, E and Stefanek, G Stock, R Strabel, C Strobele, H Susa, T and Szentpetery, I Sziklai, J Szymanski, P Trubnikov, V and Varga, D Vassiliou, M Veres, GI Vesztergombi, G Vranic, D Wetzler, A Wlodarczyk, Z Yoo, IK Zimanyi, J NA49 Collaborat

Subjects
High Energy Physics::Experiment, Nuclear Experiment
Abstract

The transverse mass m(t) distributions for antiprotons are measured at midrapidity for minimum bias Pb+Pb collisions at 158A GeV and for central Pb+Pb collisions at 20A, 30A, 40A, and 80A GeV beam energies in the fixed target experiment NA49 at the CERN SPS. The rapidity density dn/dy, inverse slope parameter T, and mean transverse mass < m(t)> derived from the m(t) distributions are studied as a function of the incident energy and the collision centrality and compared to the relevant data on proton production. The shapes of the m(t) distributions of (p) over bar and p are very similar. The ratios of the particle yields, (p) over bar /p and (p) over bar/(Lambda) over bar, are also analyzed. The (p) over bar /p ratio exhibits an increase with decreasing centrality and a steep rise with increasing beam energy. The (Lambda) over bar/(Lambda) over bar ratio increases beyond unity with decreasing beam energy.

Published
2006

10. System-size dependence of strangeness production in nucleus-nucleus collisions at root S-NN=17.3 GeV

Author

Alt, C Anticic, T Baatar, B Barna, D Bartke, J and Betev, L Bialkowska, H Billmeier, A Blume, C Boimska, B and Botje, M Bracinik, J Bramm, R Brun, R Buncic, P and Cerny, V Christakoglou, P Chvala, O Cramer, JG Csato, P and Darmenov, N Dimitrov, A Dinkelaker, P Eckardt, V and Farantatos, G Flierl, D Fodor, Z Foka, P Freund, P and Friese, V Gal, J Gazdzicki, M Georgopoulos, G Gladysz, E and Grebieszkow, K Hegyi, S Hohne, C Kadija, K Karev, A and Kliemant, M Kniege, S Kolesnikov, VI Kollegger, T and Kornas, E Korus, R Kowalski, M Kraus, I Kreps, M van Leeuwen, M Levai, P Litov, L Lungwitz, B Makariev, M and Malakhov, AI Markert, C Mateev, M Mayes, BW Melkumov, GL and Meurer, C Mischke, A Mitrovski, M Molnar, J and Mrowczynski, S Palla, G Panagiotou, AD Panayotov, D and Petridis, A Pikna, M Pinsky, L Puhlhofer, F Reid, JG and Renfordt, R Richard, A Roland, C Roland, G Rybczynski, M and Rybicki, A Sandoval, A Sann, H Schmitz, N Seyboth, P and Sikler, F Sitar, B Skrzypczak, E Stefanek, G Stock, R Strobele, H Susa, T Szentpetery, I Sziklai, J and Trainor, TA Trubnikov, V Varga, D Vassiliou, M Veres, GI and Vesztergombi, G Vranic, D Wetzler, A Wlodarczyk, Z and Yoo, IK Zaranek, J Zimanyi, J

Subjects
Nuclear Theory, Nuclear Experiment
Abstract

Emission of pi(+/-), K+/-, phi, and Lambda was measured in near-central C + C and Si + Si collisions at 158 AGeV beam energy. Together with earlier data for p + p, S + S, and Pb + Pb, the system-size dependence of relative strangeness production in nucleus-nucleus collisions is obtained. Its fast rise and the saturation observed at about 60 participating nucleons can be understood as the onset of the formation of coherent systems of increasing size.

Published
2005

11. System size and centrality dependence of the balance function in A+A collisions at root S-NN=17.2 GeV

Author

Alt, C Anticic, T Baatar, B Barna, D Bartke, J and Betev, L Bialkowska, H Billmeier, A Blume, C Boimska, B and Botje, M Bracinik, J Bramm, R Brun, R Buncic, P and Cerny, V Christakoglou, P Chvala, O Cramer, JG Csato, P and Darmenov, N Dimitrov, A Dinkelaker, P Eckardt, V and Farantatos, G Flierl, D Fodor, Z Foka, P Freund, P and Friese, V Gal, J Gazdzicki, M Georgopoulos, G Gladysz, E and Grebieszkow, K Hegyi, S Hohne, C Kadija, K Karev, A and Kliemant, M Kniege, S Kolesnikov, VI Kollegger, T and Kornas, E Korus, R Kowalski, M Kraus, I Kreps, M van Leeuwen, M Levai, P Litov, L Lungwitz, B Makariev, M and Malakhov, AI Markert, C Mateev, M Mayes, BW Melkumov, GL and Meurer, C Mischke, A Mitrovski, M Molnar, J and Mrowczynski, S Palla, G Panagiotou, AD Panayotov, D and Petridis, A Pikna, M Pinsky, L Puhlhofer, F Reid, JG and Renfordt, R Richard, A Roland, C Roland, G Rybczynski, M and Rybicki, A Sandoval, A Sann, H Schmitz, N Seyboth, P and Sikler, F Sitar, B Skrzypczak, E Stefanek, G Stock, R Strobele, H Susa, T Szentpetery, I Sziklai, J and Trubnikov, V Varga, D Vassiliou, M Veres, GI and Vesztergombi, G Vranic, D Wetzler, A Wlodarczyk, Z Yoo, IK Zaranek, J Zimanyi, J NA49 Collaboration

Subjects
High Energy Physics::Experiment, Nuclear Experiment
Abstract

Electric charge correlations were studied for p+p, C+C, Si+Si, and centrality selected Pb+Pb collisions at root s(NN) = 17.2 GeV with the NA49 large acceptance detector at the CERN SPS. In particular, long-range pseudorapidity correlations of oppositely charged particles were measured using the balance function method. The width of the balance function decreases with increasing system size and centrality of the reactions. This decrease could be related to an increasing delay of hadronization in central Pb+Pb collisions.

Published
2005

12. Omega(-) and (Omega)over-bar(+) production in central Pb+Pb collisions at 40 and 158A GeV

Author

Alt, C Anticic, T Baatar, B Barna, D Bartke, J and Betev, L Bialkowska, H Billmeier, A Blume, C Boimska, B and Botje, M Bracinik, J Bramm, R Brun, R Buncic, P and Cerny, V Christakoglou, P Chvala, O Cramer, JG Csato, P and Darmenov, N Dimitrov, A Dinkelaker, P Eckardt, V and Farantatos, G Flierl, D Fodor, Z Foka, P Freund, P and Friese, V Gal, J Gazdzicki, M Georgopoulos, G Gladysz, E and Grebieszkow, K Hegyi, S Hohne, C Kadija, K Karev, A and Kliemant, M Kniege, S Kolesnikov, VI Kollegger, T and Kornas, E Korus, R Kowalski, M Kraus, I Kreps, M van Leeuwen, M Levai, P Litov, L Lungwitz, B Makariev, M and Malakhov, AI Markert, C Mateev, M Mayes, BW Melkumov, GL and Meurer, C Mischke, A Mitrovski, M Molnar, J and Mrowczynski, S Palla, G Panagiotou, AD Panayotov, D and Petridis, A Pikna, M Pinsky, L Puhlhofer, F Reid, JG and Renfordt, R Richard, A Roland, C Roland, G Rybczynski, M and Rybicki, A Sandoval, A Sann, H Schmitz, N Seyboth, P and Sikler, F Sitar, B Skrzypczak, E Stefanek, G Stock, R Strobele, H Susa, T Szentpetery, I Sziklai, J and Trainor, TA Varga, D Vassiliou, M Veres, GI and Vesztergombi, G Vranic, D Wetzler, A Wlodarczyk, Z Yoo, IK Zaranek, J Zimanyi, J NA49 Collaboration

Subjects
High Energy Physics::Phenomenology, High Energy Physics::Experiment, Nuclear Experiment
Abstract

Results are presented on Omega production in central Pb+Pb collisions at 40 and 158A GeV beam energy. For the first time in heavy ion reactions, rapidity distributions and total yields were measured for the sum Omega(-)+(Omega) over bar (+) at 40A GeV and for Omega(-) and (Omega) over bar (+) separately at 158A GeV. The yields are strongly underpredicted by the string-hadronic UrQMD model but agree better with predictions from hadron gas models.

Published
2005

13. Directed and elliptic flow of charged pions and protons in Pb+Pb collisions at 40 and 158A GeV

Author

Alt, C, Anticic, T, Baatar, B, Barna, D, Bartke, J, Behler, M, Betev, L, Bialkowska, H, Billmeier, A, Blume, C, Boimska, B, Borghini, Nicolas, Botje, M, Bracinik, J, Bramm, R, Brun, R, Buncic, P, Cerny, V, Chvala, O, Cooper, GE, Cramer, JG, Csato, P, Dinh, PM, Dinkelaker, P, Eckardt, V, Filip, P, Fodor, Z, Foka, P, Freund, P, Friese, V, Gal, J, Gazdzicki, M, Georgopoulos, G, Gladysz, E, Hegyi, S, Hohne, C, Jacobs, P, Kadija, K, Karev, A, Kniege, S, Kolesnikov, VI, Kollegger, T, Korus, R, Kowalski, M, Kraus, I, Kreps, M, van Leeuwen, M, Levai, P, Malakhov, AI, Markert, C, Mayes, BW, Melkumov, GL, Meurer, C, Mischke, A, Mitrovski, M, Molnar, J, Mrowczynski, S, Odyniec, G, Ollitrault, JY, Palla, G, Panagiotou, AD, Perl, K, Petridis, A, Pikna, M, Pinsky, L, Poskanzer, AM, Puhlhofer, F, Reid, JG, Renfordt, R, Retyk, W, Ritter, HG, Roland, C, Roland, G, Rybczynski, M, Rybicki, A, Sandoval, A, Sann, H, Schmitz, N, Seyboth, P, Sikler, F, Sitar, B, Skrzypczak, E, Snellings, RJ, Stefanek, G, Stock, R, Strobele, H, Susa, T, Szentpetery, I, Sziklai, J, Trainor, TA, Varga, D, Vassiliou, M, Veres, GI, Vesztergombi, G, Voloshin, SA, Vranic, D, Wetzler, A, Wlodarczyk, Z, Yoo, IK, Zaranek, J, and Zimanyi, J

Subjects
FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract

Directed and elliptic flow measurements for charged pions and protons are reported as a function of transverse momentum, rapidity, and centrality for 40 and 158A GeV Pb + Pb collisions as recorded by the NA49 detector. Both the standard method of correlating particles with an event plane, and the cumulant method of studying multiparticle correlations are used. In the standard method the directed flow is corrected for conservation of momentum. In the cumulant method elliptic flow is reconstructed from genuine 4, 6, and 8-particle correlations, showing the first unequivocal evidence for collective motion in A+A collisions at SPS energies., To be published in Phys. Rev. C, 37 pages, 29 figures, version accepted for publication, contains now a weblink to data shown in the figures: See http://na49info.cern.ch/na49/Archives/Data/FlowWebPage/

Published
2003

14. Heavy quark chemical potential as probe of the phase diagram of nuclear matter

Author

Katsas, PG Panagiotou, AD Gountras, T

Subjects
High Energy Physics::Lattice, Nuclear Theory, High Energy Physics::Phenomenology, High Energy Physics::Experiment, Nuclear Experiment
Abstract

We study the temperature dependence of the strange and charm quark chemical potentials in the phase diagram of nuclear matter, within a modified and generalized hadron gas model, in order to consider phase transitions and to describe phenomena taking place outside the hadronic phase. We employ, in a phenomenological way, the Polyakov loop and scalar quark condensate order parameters, mass/temperature-scaled partition functions and enforce flavor conservation. We propose that the resulting variation of the heavy quark chemical potentials can be directly related to the quark deconfinement and chiral phase transitions. Then, the chemical potential of the strange and charm quark can be considered as an experimentally accessible “order parameter”, probing the phase diagram of QCD.

Published
2003

15. On the metastability of the cosmic-ray Centauro quark-matter fireball

Author

Theodoratou, OP Panagiotou, AD

Subjects
Astrophysics::High Energy Astrophysical Phenomena, High Energy Physics::Phenomenology, Nuclear Theory, Nuclear Experiment
Abstract

We discuss the possible metastability of the cosmic-ray Centauro quark-matter fireball in terms of the equalization of thr quark-gluon and vacuum pressures and the radius of the fireball, as deduced from the calculated thermodynamic quantities. We obtain the bag-stability curves as a function of T, mu q and the bag radius R and we find that the Centauro fireball is situated within one standard deviation from these curves. This fact, together with the very high baryon density and binding energy and the low entropy per baryon of the state, prompt us to conjecture that the Centauro fireball may possibly be a metastable state. (C) 2000 Elsevier Science B.V. All rights reserved.

Published
2000

16. The grid-geometry time-of-flight detector used in the NA49 experiment at the CERN-SPS

Author

Palla, G Csato, P Fodor, Z Sikler, F Szentpetery, I and Sziklai, J Vesztergombi, G Panagiotou, AD

Subjects
Physics::Instrumentation and Detectors, High Energy Physics::Experiment, Nuclear Experiment
Abstract

The high time and position resolution grid geometry time-of-flight spectrometer is described. It is used for particle identification as an element of the NA49 hadron detector system at the CERN-SPS. Performance and operational experience in high particle density environment of Ph + Pb collision are discussed. (C) 2000 Elsevier Science B.V. All rights reserved.

Published
2000

17. Deuteron production in central Pb plus Pb collisions at 158A GeV

Author

Afanasiev, SV Anticic, T Bachler, J Barna, D Barnby, LS and Bartke, J Barton, RA Betev, L Bialkowska, H and Billmeier, A Blume, C Blyth, CO Boimska, B Bracinik, J and Brady, FP Brun, R Buncic, P Carr, L Cebra, D and Cooper, GE Cramer, JG Csato, P Eckardt, V Eckhardt, F and Ferenc, D Fischer, HG Fodor, Z Foka, P Freund, P and Friese, V Ftacnik, J Gal, J Ganz, R Gazdzicki, M and Gladysz, E Grebieszkow, J Harris, JW Hegyi, S Hlinka, V and Hohne, C Igo, G Ivanov, M Jacobs, P Janik, R and Jones, PG Kadija, K Kolesnikov, VI Kowalski, M Lasiuk, B and Levai, P Malakhov, AI Margetis, S Markert, C Mayes, BW Melkumov, GL Mischke, A Molnar, J Nelson, JM and Odyniec, G Oldenburg, MD Palla, G Panagiotou, AD and Petridis, A Pikna, M Pinsky, L Poskanzer, AM Prindle, DJ and Puhlhofer, F Reid, JG Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C Roland, G Rybicki, A Sammer, T Sandoval, A Sann, H Semenov, AY Schafer, E and Schmitz, N Seyboth, P Sikler, F Sitar, B Skrzypczak, E and Snellings, R Squier, GTA Stock, R Strmen, P and Strobele, H Struck, C Susa, T Szarka, I Szentpetery, I and Sziklai, J Toy, M Trainor, TA Trentalange, S and Ullrich, T Varga, D Vassiliou, M Veres, GI Vesztergombi, G Voloshin, S Vranic, D Wang, F Weerasundara, DD and Wenig, S Whitten, C Xu, N Yates, TA Yoo, IK Zimanyi, J

Abstract

Experimental results on deuteron emission from central Pb + Pb collisions (E-beam = 158A GeV, fixed target), obtained by NA49 at the CERN SPS accelerator, are presented. The transverse mass in, distribution was measured near mid-rapidity (2.0 < y < 2.5) in the range of 0 < m(t) - m(0) < 0.9 GeV/c(2) (0 < p(t) < 2.0 GeV/c) for the 4% most central collisions. An exponential fit gives an inverse slope T-d = (450 +/- 30) MeV and a yield dN(d)/dy = 0.34 +/- 0.03. The coalescence factor B-2 (m(t) = m(0))=(3.5 +/- 1.0) . 10(-4) GeV2 and its m(t)-dependence are deter-mined and discussed in terms of a model that includes the collective expansion of the source created in a collision. The derived Gaussian size parameter R-G Of the emission volume is consistent with earlier HBT results on the source of pion emission. (C) 2000 Elsevier Science B.V. All rights reserved.

Published
2000

18. Production of phi-mesons in p + p, p + Pb and central Pb + Pb collisions at E-beam=158 A GeV

Author

Afanasiev, SV Anticic, T Bachler, J Barna, D Barnby, LS and Bartke, J Barton, RA Betev, L Bialkowska, H and Billmeier, A Blume, C Blyth, CO Boimska, B Bracinik, J and Brady, FP Brun, R Buncic, P Carr, L Cebra, D and Cooper, GE Cramer, JG Csato, P Eckardt, V Eckhardt, F and Ferenc, D Fischer, HG Fodor, Z Foka, P Freund, P and Friese, V Ftacnik, J Gal, J Ganz, R Gazdzicki, M and Gladysz, E Grebieszkow, J Harris, JW Hegyi, S Hlinka, V and Hohne, C Igo, G Ivanov, M Jacobs, P Janik, R and Jones, PG Kadija, K Kolesnikov, VI Kowalski, M Lasiuk, B and Levai, P Malakhov, AI Margetis, S Markert, C Mayes, BW Melkumov, GL Mischke, A Molnar, J Nelson, JM and Odyniec, G Oldenburg, MD Palla, G Panagiotou, AD and Petridis, A Pikna, M Pinsky, L Poskanzer, AM Prindle, DJ and Puhlhofer, F Reid, JG Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C Roland, G Rybicki, A Sammer, T Sandoval, A Sann, H Semenov, AY Schafer, E and Schmitz, N Seyboth, P Sikler, F Sitar, B Skrzypczak, E and Snellings, R Squier, GTA Stock, R Strmen, P and Strobele, H Susa, T Szarka, I Szentpetery, I Sziklai, J and Toy, M Trainor, TA Trentalange, S Ullrich, T Varga, D Vassiliou, M Veres, GI Vesztergombi, G Voloshin, S and Vranic, D Wang, F Weerasundara, DD Wenig, S Whitten, C and Xu, N Yates, TA Yoo, IK Zimanyi, J NA49 Collaboration

Abstract

Yields and phase space distributions of phi -mesons emitted from p + p (minimum bias trigger), p + Pb (at various centralities) and central Pb + Pb collisions are reported (E-beam = 158 A GeV). The decay phi –> K+K- was used for identification. The phi/pi ratio is found to increase by a factor of 3.0 +/- 0.7 from inelastic p + p to central Pb + Pb. Significant enhancement in this ratio is also observed in subclasses of p + p events (characterized by high charged-particle multiplicity) as well as in the forward hemisphere of central p + Pb collisions. In Pb + Pb no shift or significant broadening of the phi -peak is seen. (C) 2000 Published by Elsevier Science B.V.

Published
2000

19. Formation and identification of Centauro and Strangelets in nucleus-nucleus collisions at the LHC

Author

Angelis, ALS Bartke, J Bogolyubsky, MY Filippov, SN and Gladysz-Dziadus, E Kharlov, YV Kurepin, AB Maevskaya, AI and Mavromanolakis, G Panagiotou, AD Sadovsky, SA Stefanski, P and Wlodarczyk, Z

Subjects
Physics::Plasma Physics, Physics::Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, Nuclear Theory, Nuclear Experiment
Abstract

We present a phenomenological model for the formation and decay of a cosmic ray Centauro fireball in the baryon-rich projectile fragmentation rapidity region in nucleus-nucleus interactions. Our model naturally incorporates the possibility of Strangelet formation, Strangelets being conjectured to be the “strongly penetrating component” observed in hadron-rich cosmic ray events. Based on this model we have performed Monte-Carlo simulations to study the Centauro and Strangelet dynamic and kinematic characteristics in central Pb+Pb collisions at LHC energies, as well as their identification by the detector system CASTOR. CASTOR is being developed for the ALICE heavy ion experiment at the LHC and will probe the very forward pseudorapidity region 5.6 less than or equal to eta less than or equal to 7.2, characterized by very high baryon density. CASTOR is optimised to search for Centauro signatures and long penetrating objects. Simulations show that CASTOR is well able to distinguish events with abnormal values of E(em)/E(had) or N(gamma)/N(ch). In addition simulations of the transition curves of Strangelets traversing the CASTOR calorimeter show long penetration and many-maxima structure such as observed in cosmic ray events.

Published
1999

20. Baryon Stopping and Charged Particle Distributions in Central Pb+Pb Collisions at 158 GeV per Nucleon

Author

Appelshauser, H Bachler, J Bailey, SJ Barnby, LS Bartke, J Barton, RA Bialkowska, H Billmeier, A Blyth, CO and Bock, R Boimska, B Bormann, C Brady, FP Brockmann, R and Brun, R Buncic, P Caines, HL Cebra, D Cooper, GE and Cramer, JG Csato, P Dunn, J Eckardt, V Eckhardt, F and Ferguson, MI Fischer, HG Flierl, D Fodor, Z Foka, P and Freund, P Friese, V Fuchs, M Gabler, F Gal, J Ganz, R Gazdzicki, M Geist, W Gladysz, E Grebieszkow, J and Gunther, J Harris, JW Hegyi, S Henkel, T Hill, LA and Huang, I Hummler, H Igo, G Irmscher, D Jacobs, P and Jones, PG Kadija, K Kolesnikov, VI Kowalski, M Lasiuk, B and Levai, P Malakhov, AI Margetis, S Markert, C and Melkumov, GL Mock, A Molnar, J Nelson, JM Oldenburg, M and Odyniec, G Palla, G Panagiotou, AD Petridis, A and Piper, A Porter, RJ Poskanzer, AM Poziombka, S Prindle, DJ Puhlhofer, F Reid, JG Renfordt, R Retyk, W and Ritter, HG Rohrich, D Roland, C Roland, G Rudolph, H and Rybicki, A Sandoval, A Sann, H Semenov, AY Schafer, E and Schmischke, D Schmitz, N Schonfelder, S Seyboth, P and Sikler, F Skrzypczak, E Squier, GTA Stock, R Strobele, H and Szentpetery, I Sziklai, J Toy, M Trainor, TA and Trentalange, S Ullrich, T Vassiliou, M Vesztergombi, G and Vranic, D Wang, F Weerasundara, DD Wenig, S Whitten, C and Wienold, T Wood, L Xu, N Yates, TA Zimanyi, J and Zhu, XZ Zybert, R NA49 Collaboration

Subjects
Nuclear Theory, Nuclear Physics - Experiment, Nuclear Experiment
Abstract

Net proton and negative hadron spectra for central Pb + Pb collisions at 158 GeV per nucleon at the CERN Super Proton Synchrotron were measured and compared to spectra from lighter systems. Net baryon distributions were derived from those of net protons. Stopping (rapidity shift with respect to the beam) and mean transverse momentum [p(T)] of net baryons increase with system size. The rapidity density of negative hadrons scales with the number of participant nucleons for nuclear collisions, whereas their [p(T)] is independent of system size. The [p(T)] dependence upon particle mass and system size is consistent with larger transverse flow velocity at midrapidity for Pb + Pb compared to S + S central collisions.

Published
1999

21. The NA49 large acceptance hadron detector

Author

Afanasiev, S Alber, T Appelshauser, H Bachler, J Barna, D Barnby, LS Bartke, J Barton, RA Betev, L and Bialkowska, H Bieser, F Billmeier, A Blyth, CO Bock, R and Bormann, C Bracinik, J Brady, FP Brockmann, R Brun, R Buncic, P Caines, HL Cebra, D Cooper, GE Cramer, JG Csato, P Cyprian, M Dunn, J Eckardt, V Eckhardt, F Empl, T Eschke, J Ferguson, MI Fessler, H Fischer, HG Flierl, D Fodor, Z Frankenfeld, U Foka, P Freund, P Friese, V Ftacnik, J Fuchs, M Gabler, F Gal, J and Ganz, R Gazdzicki, M Gladysz, E Grebieszkow, J Gunther, J Harris, JW Hegyi, S Henkel, T Hill, LA Hlinka, V and Huang, I Hummler, H Igo, G Irmscher, D Ivanov, M and Janik, R Jacobs, P Jones, PG Kadija, K Kolesnikov, VI and Kowalski, M Lasiuk, B Levai, P Liebicher, K Lynen, U and Malakhov, AI Margetis, S Markert, C Marks, C Mayes, B Melkumov, GL Mock, A Molnar, J Nelson, JM and Oldenburg, M Odyniec, G Palla, G Panagiotou, AD Pestov, Y Petridis, A Pikna, M Pimpl, W Pinsky, L Piper, A and Porter, RJ Poskanzer, AM Poziombka, S Prindle, DJ and Puhlhofer, F Rauch, W Reid, JG Renfordt, R Retyk, W and Ritter, HG Rohrich, D Roland, C Roland, G Rudolph, H and Rybicki, A Sammer, T Sandoval, A Sann, H Schafer, E and Schmidt, R Schmischke, D Schmitz, N Schonfelder, S and Semenov, AY Seyboth, J Seyboth, P Seyerlein, J Sikler, F and Sitar, B Skrzypczak, E Squier, GTA Stelzer, H Stock, R Strmen, P Strobele, H Struck, C Susa, T Szarka, I and Szentpetery, I Szymanski, P Sziklai, J Toy, M and Trainor, TA Trentalange, S Ullrich, T Vassiliou, M and Veres, G Vesztergombi, G Vranic, D Wang, FQ and Weerasundara, DD Wenig, S Whitten, C Wieman, H Wienold, T Wood, L Yates, TA Zimanyi, J Zhu, XZ Zybert, R

Subjects
Physics::Instrumentation and Detectors, High Energy Physics::Experiment, Nuclear Experiment
Abstract

The NA49 detector is a wide acceptance spectrometer for the study of hadron production in p + p, p + A, and A + A collisions at the CERN SPS. The main components are 4 large-volume TPCs for tracking and particle identification via dE/dx. TOF scintillator arrays complement particle identification Calorimeters for transverse energy determination and triggering, a detector for centrality selection in p + A collisions, and beam definition detectors complete the set-up. A description of all detector components is given with emphasis on new technical realizations. Performance and operational experience are discussed in particular with respect to the high track density environment of central Pb + Pb collisions. (C) 1999 Elsevier Science B.V. All rights reserved.

Published
1999

22. Two-proton correlations from 158 A GeV Pb+Pb central collisions

Author

Appelshauser, H Bachler, J Bailey, SJ Barna, D Barnby, LS Bartke, J Barton, RA Betev, L Bialkowska, H and Billmeier, A Blyth, CO Bock, R Boimska, B Bormann, C and Brady, FP Brockmann, R Brun, R Buncic, P Caines, HL and Carr, LD Cebra, D Cooper, GE Cramer, JG Cristinziani, M and Csata, P Dunn, J Eckardt, V Eckhardt, F Ferguson, MI and Fischer, HG Flierl, D Fodor, Z Foka, P Freund, P and Friese, V Fuchs, M Gabler, F Gal, J Ganz, R and Gazdzicki, M Geist, W Gladysz, E Grebieszkow, J Gunther, J Harris, JW Hegyi, S Henkel, T Hill, LA Hummler, H and Igo, G Irmscher, D Jacobs, P Jones, PG Kadija, K and Kolesnikov, VI Kowalski, M Lasiuk, B Lednicky, R Levai, P Malakhov, AI Margetis, S Markert, C Melkumov, GL and Mock, A Molnar, J Nelson, JM Oldenburg, M Odyniec, G and Palla, G Panagiotou, AD Petridis, A Piper, A Porter, RJ and Poskanzer, AM Prindle, DJ Puhlhofer, F Susa, T Reid, JG Renfordt, R Retyk, W Ritter, HG Rohrich, D and Roland, C Roland, G Rudolph, H Rybicki, A Sammer, T and Sandoval, A Sann, H Semenov, AY Schafer, E Schmischke, D and Schmitz, N Schonfelder, S Seyboth, P Sikler, F and Skrzypczak, E Snellings, R Squier, GTA Stock, R and Strobele, H Struck, C Szentpetery, I Sziklai, J Toy, M and Trainor, TA Trentalange, S Ullrich, T Vassiliou, M and Veres, G Vesztergombi, G Voloshin, S Vranic, D Wang, F and Weerasundara, DD Wenig, S Whitten, C Wood, L Xu, N and Yates, TA Zimanyi, J Zhu, XZ Zybert, R

Subjects
Nuclear Theory, High Energy Physics::Experiment, Nuclear Experiment
Abstract

The two-proton correlation function at midrapidity from Pb + Pb central collisions at 158 A GeV has been measured by the NA49 experiment. The results are compared to model predictions from static thermal Gaussian proton source distributions and transport models rqmd and venus. An effective proton source size is determined by minimizing chi(2)/ndf between the correlation functions of the data and those calculated for the Gaussian sources, yielding sigma(eff) = 3.85 +/- 0.15(stat.)(-0.25)(+0.60)(syst.) fm. Both the rqmd and the venus model are consistent with the data within the error in the correlation peak region. (C) 1999 Published by Elsevier Science B.V. All rights reserved.

Published
1999

23. Event-by-event fluctuations of average transverse momentum in central Pb plus Pb collisions at 158 GeV per nucleon

Author

Appelshauser, H Bachler, J Bailey, SJ Barna, D Barnby, LS Bartke, J Barton, RA Betev, L Bialkowska, H and Billmeier, A Blyth, CO Bock, R Boimska, B Bormann, C and Brady, FP Brockmann, R Brun, R Buncic, P Caines, HL and Carr, LD Cebra, D Cooper, GE Cramer, JG Cristinziani, M and Csato, P Dunn, J Eckardt, V Eckhardt, F Ferguson, MI and Fischer, HG Flierl, D Fodor, Z Foka, P Freund, P and Friese, V Fuchs, M Gabler, F Gal, J Ganz, R and Gazdzicki, M Geist, W Gladysz, E Grebieszkow, J Gunther, J Harris, JW Hegyi, S Henkel, T Hill, LA Hummler, H and Igo, G Irmscher, D Jacobs, P Jones, PG Kadija, K and Kolesnikov, VI Kowalski, M Lasiuk, B Levai, P Malakhov, AI Margetis, S Markert, C Melkumov, GL Mock, A and Molnar, J Nelson, JM Oldenburg, M Odyniec, G Palla, G and Panagiotou, AD Petridis, A Piper, A Porter, RJ and Poskanzer, AM Prindle, DJ Puhlhofer, F Reid, JG and Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C and Roland, G Rudolph, H Rybicki, A Sammer, T Sandoval, A and Sann, H Semenov, AY Schafer, E Schmischke, D and Schmitz, N Schonfelder, S Seyboth, P Seyerlein, J and Sikler, F Skrzypczak, E Snellings, R Squier, GTA Stock, R Strobele, H Struck, C Susa, T Szentpetery, I and Sziklai, J Toy, M Trainor, TA Trentalange, S Ullrich, T and Vassiliou, M Veres, G Vesztergombi, G Voloshin, S and Vranic, D Wang, F Weerasundara, DD Wenig, S Whitten, C and Wienold, T Wood, L Xu, N Yates, TA Zimanyi, J and Zhu, XZ Zybert, R NA49 Collaboration

Subjects
Nuclear Experiment
Abstract

We present first data on event-by-event fluctuations in the average transverse momentum of charged particles produced in Pb + Pb collisions at the CERN SPS. This measurement provides previously unavailable information allowing sensitive tests of microscopic and thermodynamic collision models and to search for fluctuations expected to occur in the vicinity of the predicted QCD phase transition. We find that the observed variance of the event-by-event average transverse momentum is consistent with independent particle production modified by the known two-particle correlations due to quantum statistics and final state interactions and folded with the resolution of the NA49 apparatus. For two specific models of non-statistical fluctuations in transverse momentum limits are derived in terms of fluctuation amplitude. We show that a significant part of the parameter space for a model of isospin fluctuations predicted as a consequence of chiral symmetry restoration in a non-equilibrium scenario is excluded by our measurement. (C) 1999 Published by Elsevier Science B.V. All rights reserved.

Published
1999

24. Strangeness measurements in NA49 experiment with Pb projectiles

Author

Margetis, S., Appelshauser, H., Bachler, J., Bailey, Sj, Barna, D., Barnby, Ls, Bartke, J., Baton, Ra, Bialkowska, H., Billmeier, A., Blyth, Co, Bock, R., Bormann, C., Brady, Fp, Brockmann, R., Brun, R., Buncic, P., Caines, Hl, Lincoln Carr, Cebra, D., Cooper, Ge, Cramer, Jg, Cristinziani, M., Csato, P., Dunn, J., Eckardt, V., Eckhardt, F., Ferguson, Mi, Fischer, Hg, Flierl, D., Fodor, Z., Foka, P., Freund, P., Friese, V., Fuchs, M., Gabler, F., Gal, J., Gazdzicki, M., Gladysz, E., Grebieszkow, J., Gunther, J., Harris, Jw, Hegyi, S., Henkel, T., Hill, La, Hummler, H., Igo, G., Irmscher, D., Jacobs, P., Jones, Pg, Kadija, K., Kolesnikov, Vi, Kowalski, M., Lasiuk, B., Levai, P., Malakhov, Ai, Markert, C., Melkumov, Gl, Mock, A., Molnar, J., Nelson, Jm, Oldenburg, M., Odyniec, G., Palla, G., Panagiotou, Ad, Petridis, A., Piper, A., Porter, Rj, Poskanzer, Am, Prindle, Dj, Puhlhofer, F., Rauch, W., Reid, Jg, Renfordt, R., Retyk, W., Ritter, Hg, Rohrich, D., Roland, C., Roland, G., Rudolph, H., Rybicki, A., Sandoval, A., Sann, H., Semenov, Ay, Schafer, E., Schmischke, D., Schmitz, N., Schonfelder, S., Seyboth, P., Seyerlein, J., Sikler, F., Skrzypczak, E., Snellings, R., Squier, Gta, Stock, R., Strobele, H., Struck, C., Szentpetery, I., Sziklai, J., Toy, M., Trainor, Ta, Trentalange, S., Ullrich, T., Vassiliou, M., Veres, G., Vesztergombi, G., Vranic, D., Wang, F., Weerasundara, Dd, Wenig, S., Whitten, C., Wienold, T., Wood, L., Xu, N., Yates, Ta, Zimanyi, J., Zhu, Xz, and Zybert, R.

Subjects
NA49, heavy ion, charge strange particle, neutral strange particle, Nuclear Theory, Nuclear Experiment
Abstract

Charged and neutral strange particle production was studied by the NA49 experiment at CERN. Preliminary inclusive spectra are presented for K^+/-, K^0_S, Phi, Lamda, Antilamda and ksi^+/- particles, measured in a region close to mid-rapidity, for central Pb+Pb collisions at 158 GeV per nucleon. An enhanced strange particle production relative to properly scaled nucleon-nucleon collisions is observed, but its strength is similar to lighter S + nucleus system. The enhancement is stronger for multistrange particles.

Published
1999

25. Xi and (Xi)over-bar production in 158 GeV/nucleon Pb+Pb collisions

Author

Appelhauser, H Bachler, J Bailey, SJ Barna, D Barnby, LS and Bartke, J Barton, RA Bialkowska, H Billmeier, A and Blyth, CO Bock, R Bormann, C Brady, FP Brockmann, R and Brun, R Buncic, P Caines, HL Carr, LD Cebra, D and Cooper, GE Cramer, JG Cristinziani, M Csato, P Dunn, J and Eckardt, V Eckhardt, F Ferguson, MI Fischer, HG and Flierl, D Fodor, Z Foka, P Freund, P Friese, V and Fuchs, M Gabler, F Ganz, R Geist, W Gal, J and Gazdzicki, M Gladysz, E Grebieszkow, J Gunther, J and Harris, JW Hegyi, S Henkel, T Hill, LA Hummler, H and Igo, G Irmscher, D Jacobs, P Jones, PG Kadija, K and Kolesnikov, VI Konashenok, A Kowalski, M Lasiuk, B and Levai, P Liu, F Malakhov, AI Margetis, S Markert, C and Melkumov, GL Mock, A Molnar, J Nelson, JM Oldenburg, M and Odyniec, G Palla, G Panagiotou, AD Petridis, A and Piper, A Porter, RJ Poskanzer, AM Prindle, DJ Puhlhofer, F Rauch, W Reid, JG Renfordt, R Retyk, W Ritter, HG and Rohrich, D Roland, C Roland, G Rudolph, H Rybicki, A and Sandoval, A Sann, H Semenov, AY Schafer, E and Schmischke, D Schmitz, N Schonfelder, S Seyboth, P and Seyerlein, J Sikler, F Skrzypczak, E Snellings, R and Squier, GTA Stock, R Strobele, H Struck, C Susa, T and Szentpetery, I Sziklai, J Toy, M Trainor, TA and Trentalange, S Ullrich, T Vassiliou, M Veres, G and Vesztergombi, G Vranic, D Wang, F Weerasundara, DD and Wenig, S Whitten, C Wienold, T Wood, L Xu, N Yates, TA Zimanyi, J Zhu, XZ Zybert, R NA49 Collaboration

Abstract

We report measurements of Xi(-) and (Xi)over-bar(+) hyperon absolute yields as a function of rapidity in 158 GeV/c Ph + Pb collisions. At midrapidity, dN/dy = 2.29 +/- 0 12 for Xi(-), and 0.52 +/- 0.05 for (Xi)over-bar(+), leading to the ratio of (Xi)over-bar(+)/Xi(-) = 0.23 +/- 0.03. Inverse slope parameters fitted to the measured transverse mass spectra are of the order of T approximate to 300 MeV near mid-rapidity. The estimated total yield of Xi(-) particles in Pb+ Pb central interactions amounts to 7.4 +/- 1.0 per collision. Comparison to Xi(-) production in properly scaled p + p reactions at the same energy reveals a dramatic enhancement (about one order of magnitude) of Xi(-) production in Pb + Pb central collisions over elementary hadron interactions. (C) 1998 Elsevier Science B.V. All rights reserved.

Published
1998

26. Directed and elliptic flow in 158GeV/nucleon Pb+Pb collisions

Author

Appelshauser, H Bachler, J Bailey, SJ Barnby, LS Bartke, J Barton, RA Bialkowska, H Blyth, CO Bock, R and Bormann, C Brady, FP Brockmann, R Buncic, N Buncic, P and Caines, HL Cebra, D Cooper, GE Cramer, JG Csato, P and Dunn, J Eckardt, V Eckhardt, F Ferguson, MI Fischer, HG Flierl, D Fodor, Z Foka, P Freund, P Friese, V and Fuchs, M Gabler, F Gal, J Gazdzicki, M Gladysz, E and Grebieszkow, J Gunther, J Harris, JW Hegyi, S and Henkel, T Hill, LA Huang, I Hummler, H Igo, G and Irmscher, D Jacobs, P Jones, PG Kadija, K Kolesnikov, VI and Kowalski, M Lasiuk, B Levai, P Malakhov, AI and Margetis, S Markert, C Melkumov, GL Mock, A Molnar, J and Nelson, JM Odyniec, G Palla, G Panagiotou, AD and Petridis, A Piper, A Porter, RJ Poskanzer, AM Poziombka, S Prindle, DJ Puhlhofer, F Rauch, W Reid, JG and Renfordt, R Retyk, W Ritter, HG Rohrich, D Roland, C and Roland, G Rudolph, H Rybicki, A Sandoval, A Sann, H and Semenov, AY Schafer, E Schmischke, D Schmitz, N and Schonfelder, S Seyboth, P Seyerlein, J Sikler, F and Skrzypczak, E Squier, GTA Stock, R Strobele, H and Szentpetery, I Sziklai, J Toy, M Trainor, TA and Trentalange, S Ullrich, T Vassiliou, M Vesztergombi, G and Voloshin, S Vranic, D Wang, F Weerasundara, DD Wenig, S and Whitten, C Wienold, T Wood, L Yates, TA Zimanyi, J and Zybert, R NA49 Collaboration

Subjects
Physics::Fluid Dynamics, Nuclear Theory, Nuclear Experiment
Abstract

The directed and elliptic flow of protons and charged pions has been observed from the semicentral collisions of a 158 GeV/nucleon Ph beam with a Pb target. The rapidity and transverse momentum dependence of the flow has been measured. The directed flow of the pions is opposite to that of the protons but both exhibit negative flow at low p(t). The elliptic flow of both is fairly independent of rapidity but rises with p(t).

Published
1998

27. Charged particle production in proton-, deuteron-, oxygen- and sulphur-nucleus collisions at 200 GeV per nucleon

Author

Alber, T Appelshauser, H Bachler, J Bartke, J and Bialkowska, H Bloomer, MA Bock, R Braithwaite, WJ and Brinkmann, D Brockmann, R Buncic, P Chan, P Cramer, JG and Cramer, PB Derado, I Eberlein, B Eckardt, V Eschke, J Favuzzi, C Ferenc, D Fleischmann, B Foka, P and Freund, P Fuchs, M Gazdzicki, M Gladysz, E Grebieszkow, J Gunther, J Harris, JW Hoffmann, M Jacobs, P and Kabana, S Kadija, K Keidel, R Kowalski, M Kuhmichel, A and Lave, F Lee, JY Ljubicic, A Margetis, S Mitchell, JT and Morse, R Nappi, E Odyniec, G Paic, G Panagiotou, AD and Petridis, A Piper, A Posa, F Poskanzer, AM and Puhlhofer, F Rauch, W Renfordt, R Retyk, W Rohrich, D and Roland, G Rothard, H Runge, K Sandoval, A Schmitz, N and Schmoetten, E Sendelbach, R Seyboth, P Seyerlein, J and Skrzypczak, E Spinelli, P Stock, R Strobele, H and Teitelbaum, L Tonse, S Trainor, TA Vasileiadis, G and Vassiliou, M Vesztergombi, G Vranic, D Wenig, S Wosiek, B Zhu, X NA35 Collaboration

Subjects
Nuclear Theory, Nuclear Experiment
Abstract

The transverse momentum and rapidity distributions of net protons and negatively charged hadrons have been measured for minimum bias proton-nucleus and deuteron-gold interactions, as well as central oxygen-gold and sulphur-nucleus collisions at 200 GeV per nucleon. The rapidity density of net protons at midrapidity in central nucleus-nucleus collisions increases both with target mass for sulphur projectiles and with the projectile mass for a gold target. The shape of the rapidity distributions of net protons forward of midrapidity for d+Au and central S+Au collisions is similar. The average rapidity loss is larger than 2 units of rapidity for reactions with the gold target. The transverse momentum spectra of net protons for all reactions can be described by a thermal distribution with 'temperatures' between 145±11 MeV (p+S interactions) and 244±43 MeV (central S+Au collisions). The multiplicity of negatively charged hadrons increases with the mass of the colliding system. The shape of the transverse momentum spectra of negatively charged hadrons changes from minimum bias p+p and p+S interactions to p+Au and central nucleus-nucleus collisions. The mean transverse momentum is almost constant in the vicinity of midrapidity and shows little variation with the target and projectile masses. The average number of produced negatively charged hadrons per participant baryon increases slightly from p+p, p+A to central S+S,Ag collisions.

Published
1998

28. An extension of the statistical bootstrap model to include strangeness. Implications on particle ratios

Author

Kapoyannis, AS Ktorides, CN Panagiotou, AD

Abstract

The statistical bootstrap model (SBM) is extended to describe hadronic systems which carry the quantum number of strangeness. The study is conducted in the three-dimensional space (T, mu(q), mu(s)) of temperature, up-down, and strange chemical potentials, respectively, wherein the existence of a “critical” surface is established, which sets the:limits of the hadronic phase of matter. A second surface, defined by the null expectation value of strangeness number ([S] = 0) is also determined. The approach of the latter surface to the critical one becomes the focal point of the present considerations. Two different versions of the extended SBM are examined, corresponding to the values 2 and 4 for the exponent ct, which determines the asymptotic falloff of the mass spectrum rho(m). It is found that the alpha = 4 version has decisive physical advantages. This model is subsequently adopted to discuss (strange) particle ratios pertaining to multiparticle production processes, for which a thermal equilibrium mode of description applies. [S0556-2821(98)06413-3]

Published
1998

29. Probing the boundaries of the hadronic phase through a strangeness-including statistical bootstrap model

Author

Kapoyannis, AS Ktorides, CN Panagiotou, AD

Subjects
Nuclear Experiment
Abstract

A recently constructed strangeness-including statistical bootstrap model (SSBM), which defines the limits of the hadronic phase and provides for a phase beyond, is further extended so as to include a factor gamma(s) that describes strangeness suppression. The model is then used to analyze the multiplicity data from collision experiments in which the colliding entities form isospin symmetric systems, the primary focus being on S +S interactions (NA35 Collaboration). An optimal set of thermodynamical variables is extracted through a fit to both the inclusive 4 pi and midrapidity data. The assumption that the measured particles originate from a thermally and partial-chemically equilibrated source described by the SSBM is satisfactorily established. The proximity of the thermodynamical variables extracted from the Sf S data to the limits of the hadronic phase is systematically investigated. Finally, experimental data from p+(p) over bar collisions (UA5 Collaboration) are similarly analyzed. [S0556-2813(98)05810-5].

Published
1998

30. Spectator nucleons in Pb+Pb collisions at 158 A center dot GeV

Author

Appelshauser, H Bachler, J Bailey, SJ Barnby, LS Bartke, J Barton, RA Bialkowska, H Blyth, CO Bock, R and Bormann, C Brady, FP Brockmann, R Buncic, N Buncic, P and Caines, HL Cebra, D Chan, P Cooper, GE Cramer, JG and Cramer, PB Csato, P Dunn, J Eckardt, V Eckhardt, F and Ferguson, MI Fischer, HG Flierl, D Fodor, Z Foka, P and Freund, P Friese, V Fuchs, M Gabler, F Gal, J and Gazdzicki, M Gladysz, E Gorodetsky, P Grebieszkow, J and Gunther, J Harris, JW Hegyi, S Henkel, T Hill, LA and Huang, I Hummler, H Igo, G Irmscher, D Jacobs, P and Jones, PG Kadija, K Kolesnikov, VI Kowalski, M Lasiuk, B and Levai, P Malakhov, AI Margetis, S Markert, C and Melkumov, GL Mock, A Molnar, J Nelson, JM Odyniec, G and Palla, G Panagiotou, AD Petridis, A Piper, A Porter, RJ and Poskanzer, AM Poziombka, S Prindle, DJ Puhlhofer, F and Rauch, W Reid, JG Renfordt, R Retyk, W Ritter, HG and Rohrich, D Roland, C Roland, G Rudolph, H Rybicki, A and Sakrejda, I Sandoval, A Sann, H Semenov, AY Schafer, E and Schmischke, D Schmitz, N Schonfelder, S Seyboth, P and Seyerlein, J Sikler, F Skrzypczak, E Squier, GTA Stock, R Strobele, H Szentpetery, I Sziklai, J Toy, M and Trainor, TA Trentalange, S Ullrich, T Vassiliou, M and Vesztergombi, G Vranic, D Wang, F Weerasundara, DD and Wenig, S White, S Whitten, C Wienold, T Wood, L and Yates, TA Zimanyi, J Zhu, XZ Zybert, R NA49 Collaboration

Subjects
Nuclear Theory, Nuclear Experiment
Abstract

The composition of forward-going projectile spectator matter in fixed-target Pb+Pb collisions at 158 A.GeV at the CERN SPS has been studied as a function of centrality. The data were measured with the NA49 veto calorimeter. We observe that forward-going spectator matter in central collisions consists of 9 neutrons, 7 protons, and half a deuteron on average. At large impact parameters most spectator nucleons are bound in fragments. The relative resolution of the average impact parameter derived from the measurement of spectator neutrons is roughly 19% in the range from zero to half maximum impact parameters.

Published
1998

31. CASTOR: A dedicated detector for the detection of centauros and strangelets at the LHC

Author

Angelis, ALS Panagiotou, AD

Subjects
Physics::Instrumentation and Detectors, High Energy Physics::Experiment, Nuclear Experiment
Abstract

We present a specialized detector system, CASTOR, which, as an integral part of the ALICE experiment, will search for centauros and strangelets in central Pb + Ph collisions at the LHC. CASTOR will cover the very forward, baryon-rich pseudorapidity region 4.5 less than or equal to eta less than or equal to 6.2 and will consist of a charged particle multiplicity detector, a photon multiplicity detector and a calorimeter with electromagnetic and hadronic sections. The physics motivation is presented, along with simulation results and the detector design. The influence of the background on the identification of centauro-type events is discussed.

Published
1997

32. A new Coulomb correction method for Bose-Einstein correlations, based on the pi(+)pi(-) correlation measurements

Author

Alber, T Appelshauser, H Bachler, J Bartke, J and Bialkowska, H Bloomer, MA Bock, R Braithwaite, WJ and Brinkmann, D Brockmann, R Buncic, P Chan, P Chase, SI and Cramer, PB Cramer, JG Derado, I Eberlein, B Eckardt, V Eschke, J Ferenc, D Fleischmann, B Foka, P Freund, P Fuchs, M Gazdzicki, M Gladysz, E Gunther, J and Harris, JW Hoffman, M Jacobs, P Kabana, S Kadija, K and Kosiec, J Kowalski, M Kuhmichel, A Lahanas, M Lee, JY and Ljubicic, A Margetis, S Mitchell, JT Morse, R Nappi, E Odyniec, G Paic, G Panagiotou, AD Petridis, A and Piper, A Posa, F Poskanzer, AM Pugh, HG Puhlhofer, F and Rai, G Rauch, W Renfordt, R Retyk, W Rohrich, D and Roland, G Rothard, H Runge, K Sandoval, A Schambach, J and Schmitz, N Schmoetten, E Schneider, I Sendelbach, R and Seyboth, P Seyerlein, J Skrzypczak, E Stefansky, P and Stock, R Strobele, H Teitelbaum, L Tonse, S Trainor, TA and Vasileiadis, G Vassiliou, M Vranic, D Wenig, S and Wensveen, M Wosiek, B

Subjects
Nuclear Experiment
Abstract

We present the measured correlation functions for pi(+)pi(-), pi(-)pi(-) and pi(+)pi(+) pairs in central S+Ag collisions at 200 GeV per nucleon. The Gamov function, which has been traditionally used to correct the correlation functions of charged pions for the Coulomb interaction, is found to be inconsistent with all measured correlation functions. Certain problems which have been dominating the systematic uncertainty of the correlation analysis are related to this inconsistency. It is demonstrated that a new Coulomb correction method, based exclusively on the measured correlation function for pi(+)pi(-) pairs, may solve the problem.

Published
1997

33. An extension of the statistical bootstrap model to include strangeness

Author

Kapoyannis, AS Ktorides, CN Panagiotou, AD

Abstract

We extend the statistical bootstrap model (SBM) in order to describe hadronic systems which carry strangeness. We establish that the hadronic phase can exist only in a region of the phase space (T, mu(q), mu s), which is bounded by a ‘critical’ surface. The SBM leads to a mass spectrum with the asymptotic form rho(m) = m(-alpha) exp[T/T*], where the exponent alpha can take different values. We first employ the usual version of the SBM (alpha = 2) and impose strangeness neutrality in order to obtain the relation between the temperature and the chemical potentials mu(q), mu(s). We find an unphysical behaviour of mu(s), near the critical surface.: Subsequently, we study another version of SBM where alpha = 4 and we are led to a realistic as well as acceptable behaviour. In this case we are also able to relate the parameter of the model, T-0, (the critical temperature at zero mu(q)) with the MIT bag constant B. The relation between (T, mu(q), mu(s)) can be used to predict the particle ratios on the critical surface at the limit of the hadron gas phase.

Published
1997

34. Determination of temperature and transverse flow velocity at chemical freeze-out in relativistic nuclear interactions

Author

Panagiotou, AD Mavromanolakis, G Tzoulis, J

Subjects
Nuclear Theory, High Energy Physics::Experiment, Nuclear Experiment
Abstract

We propose a parameter-free method to determine the temperature of a thermalized state in relativistic nuclear interactions, using the experimental mu(q)/T and mu(s)/T values, obtained from strange particle ratios. The hadron gas formalism and strangeness neutrality are employed to relate the quark-chemical potential

Published
1996

35. Antibaryon production in sulphur nucleus collisions at 200 GeV per nucleon

Author

Alber, T Appelshauser, H Bachler, J Bartke, J and Bialkowska, H Bloomer, MA Bock, R Braithwaite, WJ and Brinkmann, D Brockmann, R Buncic, P Chan, P Cramer, JG and Cramer, PB Derado, I Eckardt, V Eschke, J Favuzzi, C and Ferenc, D Fleischmann, B Foka, P Freund, P Fuchs, M and Gazdzicki, M Gladysz, E Grebieszkow, J Gunther, J and Harris, JW Hoffmann, M Jacobs, P Kabana, S Kadija, K and Kowalski, M Kuhmichel, A Lee, JY Ljubicic, A Margetis, S and Mitchell, JT Morse, R Nappi, E Odyniec, G Paic, G and Panagiotou, AD Petridis, A Piper, A Posa, F and Poskanzer, AM Puhlhofer, F Rauch, W Renfordt, R Retyk, W and Rohrich, D Roland, G Rothard, H Runge, K Sandoval, A and Schmitz, N Schmoetten, E Sendelbach, R Seyboth, P and Seyerlein, J Skrzypczak, E Spinelli, P Stock, R and Strobele, H Trainor, TA Vasileiadis, G Vassiliou, M and Vranic, D Wenig, S Wosiek, B Zhu, X

Subjects
Nuclear Theory, Nuclear Experiment
Abstract

Antiproton production near midrapidity has been studied in central collisions of S-32 With sulphur, silver and gold nuclei at 200 GeV per nucleon. The measured transverse mass distributions can be described by an exponential with inverse slope parameters of about 200 MeV, similar to those obtained from spectra. The rapidity density increases weakly with the target mass, ranging from 0.4 to 0.7. The ratio near midrapidity is approximately 1.4 on average, significantly larger than the corresponding ratio observed in proton-proton and proton-nucleus collisions.

Published
1996

37. TRANSVERSE ENERGY-PRODUCTION IN PB-208+PB COLLISIONS AT 158 GEV PER NUCLEON

Author

ALBER, T APPELSHAUSER, H BACHLER, J BARTKE, J and BIALKOWSKA, H BIESER, F BLOOMER, MA BLYTH, CO ROCK, R and BORMANN, C BRADY, FP BROCKMANN, R BUNCIC, P CAINES, HL CEBRA, D CHAN, P COOPER, GE CRAMER, JG CRAMER, PB and CSATO, P DERADO, I DUNN, J ECKARDT, V ECKHARDT, F and EULER, S FERGUSON, MI FISCHER, HG FODOR, Z FOKA, P and FREUND, P FUCHS, M GAL, J GAZDZICKI, M GLADYSZ, E and GREBIESZKOW, J GUNTHER, J HARRIS, JW HECK, W HEGYI, S HILL, LA HUANG, I HOWE, MA IGO, G IRMSCHER, D and JACOBS, P JONES, PG KADIJA, K KECSKEMETI, J KOWALSKI, M and KUHMICHEL, A LASIUK, B MARGETIS, S MITCHELL, JW and MOCK, A NELSON, JM ODYNIEC, G PALINKAS, J PALLA, G and PANAGIOTOU, AD PETRIDIS, A PIPER, A POSKANZER, AM and PRINDLE, DJ PUHLHOFER, F RAUCH, W RENFORDT, R RETYK, W and RITTER, HG ROHRICH, D RUDOLPH, H RUNGE, K SANDOVAL, A SANN, H SCHAFER, E SCHMITZ, N SCHONFELDER, S and SEYBOTH, P SEYERLEIN, J SIKLER, F SKRZYPCZAK, E STOCK, R and STROBELE, H SZENTPETERY, I SZIKLAI, J TOY, M and TRAINOR, TA TRENTALANGE, S VASSILIOU, M VESZTERGOMBI, G and VRANIC, D WENIG, S WHITTEN, C WIENOLD, T WOOD, L and ZIMANYI, J ZHU, XZ ZYBERT, R

Subjects
High Energy Physics::Experiment, Nuclear Experiment
Abstract

Measurements of the forward and the transverse energy in 158 GeV per nucleon Pb-208 + Pb collisions are presented. A total transverse energy of about 1 TeV is created in central collisions. An energy density of about 3 GeV/fm(3) is estimated for near head-on collisions. Only statistical fluctuations are seen in the ratio of electromagnetic to hadronic transverse energy.

Published
1995

39. A NOVEL GRID GEOMETRY OF LONG DETECTOR MODULES FOR A TIME-OF-FLIGHT SYSTEM

Author

DASKALAKIS, G PANAGIOTOU, AD IOANNIDIS, GS

Abstract

We present a novel geometry for a large area TOF system, consisting of long detector modules arranged in X-Y directions in two planes. Such a GRID geometry has many advantages, including better particle identification and fewer modules (channels) for the same number of identified particles, compared to a single plane geometry, i.e. a TILE arrangement. We also present the mathematical algorithm for the general case of an n-plane GRID geometry and discuss its applicability.

Published
1993

40. POSSIBILITY OF OBSERVING CENTAURO EVENTS AT THE BNL RELATIVISTIC HEAVY-ION COLLIDER

Author

PANAGIOTOU, AD PETRIDIS, A VASSILIOU, M

Subjects
Nuclear Theory, Nuclear Experiment
Abstract

A phenomenological model for the production of “Centauro”-type cosmic-ray events is developed, assuming a nucleus-nucleus interaction in the upper atmosphere. The model is used to estimate, in a self-consistent way, several thermodynamic and kinematical quantities, characterizing the observed Centauro events. On the basis of this model, we describe a typical “Centauro” event, possibly produced in the fragmentation rapidity of an A + A central collision at square-root s = 200 A GeV at the BNL Relativistic Heavy Ion Collider. We suggest several characteristic signatures for these events, as well as the possibility of observing “strangelets.”

Published
1992

41. MULTIPLICITY AND TRANSVERSE ENERGY FLUX IN O-16+PB AT 200 GEV PER NUCLEON

Author

BAMBERGER, A BANGERT, D BARTKE, J BIALKOWSKA, H BOCK, R and BROCKMANN, R DEMARZO, C DEPALMA, M DERADO, I and ECKARDT, V FAVUZZI, C FENT, J FERENC, D FESSLER, H and FREUND, P GAZDZICKI, M GEBAUER, HJ GEISSLER, K GUERRA, C and HARRIS, JW HECK, W HUMANIC, T KADIJA, K KEIDEL, R and KOWALSKI, M MARGETIS, S NAPPI, E ODYNIEC, G PAIC, G and PANAGIOTOU, AD PETRIDIS, A PFENNIG, J POSA, F and PRETZL, KP PUGH, HG PUHLHOFER, F RAI, G RANIERI, A and RENFORDT, R ROHRICH, D RUNGE, K SANDOVAL, A SCHALL, D and SCHMITZ, N SCHROEDER, LS SELVAGGI, G SEYBOTH, P and SEYERLEIN, J SKRZYPCZAK, E SPINELLI, P STOCK, R and STROBELE, H THOMAS, A TINCKNELL, M TEITELBAUM, L and VESZTERGOMBI, G VRANIC, D WENIG, S WENSVEEN, M

Published
1987

43. CHARGED-PARTICLE MULTIPLICITIES AND INELASTIC CROSS-SECTIONS IN HIGH-ENERGY NUCLEAR COLLISIONS

Author

BAMBERGER, A BANGERT, D BARTKE, J BIALKOWSKA, H BOCK, R and BROCKMANN, R CHASE, SI DEMARZO, C DEPALMA, M DERADO, I ECKARDT, V FAVUZZI, C FENT, J FERENC, D FESSLER, H and FREUND, P GAZDZICKI, M GEBAUER, HJ GEISSLER, K and GLADYSZ, E GUERRA, C HARRIS, JW HECK, W HUMANIC, T and KADIJA, K KARABARBOUNIS, A KEIDEL, R KOSIEC, J KOWALSKI, M MARGETIS, S NAPPI, E ODYNIEC, G PAIC, G and PANAGIOTOU, AD PETRIDIS, A PFENNIG, J POSA, F PRETZL, KP and PUGH, HG PUHLHOFER, F RAI, G RANIERI, A RAUCH, W and RENFORDT, R ROHRICH, D RUNGE, K SANDOVAL, A SCHALL, D and SCHMITZ, N SCHROEDER, LS SELVAGGI, G SEYBOTH, P and SEYERLEIN, J SKRZYPCZAK, E SPINELLI, P STOCK, R and STROBELE, H THOMAS, A TINCKNELL, M TEITELBAUM, L and VESZTERGOMBI, G VRANIC, D WENIG, S

Published
1988

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