2004/09/14 by T. S. Biro, Tamás S. Bíró, G. Györgyi +8
Engineering · Mathematics · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #FOS: Physical sciences #Gas Dynamics and Kinetic Theory #High Energy Physics - Phenomenology (hep-ph) #Radiative Heat Transfer Studies #hep-ph
paper · pdf · doi:10.48550/arxiv.hep-ph/0409157
20 pages in preprint format incl. 3 figures
arxiv created 2004/09/14 · openalex publication_date 2004/09/14 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We propose that transverse momentum spectra with power-law tails observed in ultrarelativistic heavy ion collisions can be interpreted as originating in a medium in thermal equilibrium. General conditions on the dynamical equations are formulated, leading in equilibrium to various energy distributions of particles. Starting with the linear Fokker-Planck equation we analyze conditions for Boltzmann-Gibbs, Tsallis, or other equilibrium distributions based upon the dependence of fluctuation and dissipation on the energy of the observed subsystem. RHIC neutral pion data definitely exclude Boltzmann-Gibbs distribution over the entire range of observed transverse momenta.