Thermal quark production in ultra-relativistic nuclear collisions

Abstract

We calculate thermal production of u, d, s, c and b quarks in ultra-relativistic heavy ion collisions. The following processes are taken into account: thermal gluon decay (g to ibar i), gluon fusion (g g to ibar i), and quark-antiquark annihilation (jbar j to ibar i), where i and j represent quark species. We use the thermal quark masses, $m_i^2(T)\simeq m_i^2+(2g^2/9)T^2$, in all the rates. At small mass ($m_i(T)<2T$), the production is largely dominated by the thermal gluon decay channel. We obtain numerical and analytic solutions of one-dimensional hydrodynamic expansion of an initially pure glue plasma. Our results show that even in a quite optimistic scenario, all quarks are far from chemical equilibrium throughout the expansion. Thermal production of light quarks (u, d and s) is nearly independent of species. Heavy quark (c and b) production is quite independent of the transition temperature and could serve as a very good probe of the initial temperature. Thermal quark production measurements could also be used to determine the gluon damping rate, or equivalently the magnetic mass.

14 pages (latex) plus 6 figures (uuencoded postscript files); CERN-TH.7038/93

References in corpus (4)

• Parton Equilibration in Relativistic Heavy Ion Collisions
• Thermal Field Theory and Infinite Statistics
• Thermal quark production in pure glue and quark gluon plasmas
• Pre-equilibrium dileptons look thermal

Cited by in corpus (14)

• Physics and Signatures of the Quark - Gluon Plasma
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• Charmonium in the vector channel at finite temperature from QCD sum rules
• QCD phase diagram from finite energy sum rules
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• Strange hadron production in heavy ion collisions from SPS to RHIC
• Heavy-light quark pseudoscalar and vector mesons at finite temperature
• (Pseudo)Scalar Charmonium in Finite Temperature QCD
• Bottonium in QCD at finite temperature
• Effect of baryon density on parton production, chemical equilibration and thermal photon emission from quark gluon plasma
• Gluon Decay as a Mechanism for Strangeness Production in a Quark-Gluon Plasma
• QCD sum rules and thermal properties of Charmonium in the vector channel
• Heavy resonance production in high energy nuclear collisions
• Particle production in matter at extreme conditions