1999/04/13 by NA49 collaboration, H. Appelshäuser, H. Appelshauser +99 · 3 citations
Physics and Astronomy · #Amplitude #Event (particle physics) #High-Energy Particle Collisions Research #Impact parameter #Isospin #Large Hadron Collider #Momentum (technical analysis) #Nuclear physics #Nucleon #Particle (ecology) #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum mechanics #Transverse plane #hep-ex
paper · pdf · doi:10.1016/s0370-2693(99)00673-5
published as Phys.Lett.B459:679-686,1999 · 6 pages, 2 figures, submitted to Phys. Lett. B
arxiv created 1999/04/13 · openalex publication_date 1999/07/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
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.