报告题目:Nucleosynthesis in heavy-ion collisions at the LHC via the Saha equation

报  告  人:Carsten Greiner,德国法兰克福大学

报告时间:2019-08-22 10:00

报告地点:物理系理科楼B315

报告摘要: The production of light (anti-)(hyper-)nuclei in heavy-ion collisions at the LHC is considered in the framework of the Saha equation, making use of the analogy between the evolution of the early universe after the Big Bang and that of "Little Bangs" created in the lab. Assuming that disintegration and regeneration reactions involving light nuclei proceed in relative chemical equilibrium after the chemical freeze-out of hadrons, their abundances are determined through the famous cosmological Saha equation of primordial nucleosynthesis and show no exponential dependence on the temperature typical for the thermal model. A quantitative analysis, performed using the hadron resonance gas model in partial chemical equilibrium, shows agreement with experimental data of the ALICE collaboration on d, 3He, 3ΛH, and 4He yields for a very broad range of temperatures at T≤155 MeV. The presented picture is supported by the observed suppression of resonance yields in central Pb-Pb collisions at the LHC.