2001/05/15 by S. Kabana, Sonja Kabana, Kabana, Sonja
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.48550/arxiv.hep-ph/0105152
8 pages, 5 figures, XXXVIth Rencontres de Moriond on 'QCD and high energy hadronic interactions', 17-24 March 2001, Les Arcs 1800, France
arxiv created 2001/05/15 · openalex publication_date 2001/05/15 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The temperature at the chemical freeze-out and at zero baryochemical potential has been extracted in a global analysis of e+e-, p+p, p+ p and A+A collisions at √(s)=2-1800 GeV per N+N pair. We demonstrate that the temperature at μB=0, rises with the initial energy density εi, and saturates above εi ∼ 1 GeV/fm3. This behaviour is interpreted as mapping out the QCD phase transition universally in particle and nuclear collisions. The critical energy density is therefore identified to be εcrit ∼ 1 ± 0.3 GeV/fm3. We show that strange particles at μB=0, are not significantly enhanced in A+A collisions as compared to p+ p. The so called 'strangeness suppression factor' (λs = \frac(2 s) (u + d)) as a function of εi is following the temperature, rising and saturating universally above εcrit. This leads to a reinterpretation of strangeness enhancement as QGP signature. Within this interpretation the experimental puzzles with respect to strangeness production can be naturally explained: e.g. the recent measured maximum of K+/π+ in Pb+Pb collisions at 40 A GeV, is explained as due to μB. We discuss under which conditions 'strangeness enhancement' and 'J/Ψ suppresion' both set in at εcrit ∼ 1 GeV/fm3.