Ερευνητικό υλικό ΕΚΠΑ

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

Αγγλικά

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.

1999

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

PHYSICS LETTERS B

ELSEVIER SCIENCE BV

459

4

679-686

https://doi.org/10.1016/S0370-2693(99)00673-5

10.1016/S0370-2693(99)00673-5

https://pergamos.lib.uoa.gr/uoa/dl/object/3052018