2002/12/09 by Mark D. Baker, B. B. Back, M. D. Baker +65 · 2 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #nucl-ex
paper · pdf · doi:10.1016/s0375-9474(02)01414-8
published as Nucl.Phys.A715:65-74,2003 · QM2002 plenary talk, 10 pages, 11 figures
arxiv created 2002/12/09 · openalex publication_date 2003/03/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Particle production in Au+Au collisions has been measured in the PHOBOS experiment at RHIC for a range of collision energies. Three empirical observations have emerged from this dataset which require theoretical examination. First, there is clear evidence of limiting fragmentation. Namely, particle production in central Au+Au collisions, when expressed as dN/dη' (η' ≡ η-ybeam), becomes energy independent at high energy for a broad region of η' around η'=0. This energy-independent region grows with energy, allowing only a limited region (if any) of longitudinal boost-invariance. Second, there is a striking similarity between particle production in e+e- and Au+Au collisions (scaled by the number of participating nucleon pairs). Both the total number of produced particles and the longitudinal distribution of produced particles are approximately the same in e+e- and in scaled Au+Au. This observation was not predicted and has not been explained. Finally, particle production has been found to scale approximately with the number of participating nucleon pairs for Npart>65. This scaling occurs both for the total multiplicity and for high \pT particles (3 <\pT< 4.5 GeV/c).