Thermal Equilibration in an Expanding Parton Plasma

Abstract

Thermalization in an expanding parton plasma is studied within the framework of Boltzmann equation in the absence of any mean fields. In particular, we study the time-dependence of the relaxation time to the lowest order in finite temperature QCD and how such time-dependence affects the thermalization of an expanding parton plasma. Because of Debye screening and Landau damping at finite temperature, the relaxation time (or transport rates) is free of infrared divergencies in both longitudinal and transverse interactions. The resultant relaxation time decreases with time in an expanding plasma like $1/{\tau }^{\beta }$, with $\beta <1$. We prove in this case that thermal equilibrium will eventually be established given a long life-time of the system. However, a fixed momentum cut-off in the calculation of the relaxation time gives rise to a much stronger time dependence which will slow down thermal equilibrium. It is also demonstrated that the ``memory effect'' of the initial condition affects the approach to thermal equilibrium and the final entropy production.

24 pages in LaTex with embedded psfigures using psfig.sty , to appear in Nucl. Phys. B

References in corpus (12)

• HIJING 1.0: A Monte Carlo Program for Parton and Particle Production in High Energy Hadronic and Nuclear Collisions
• Parton Equilibration in Relativistic Heavy Ion Collisions
• Damping rates for moving particles in hot QCD
• Viscosities of Quark-Gluon Plasmas
• Open Charm Production in an Equilibrating Parton Plasma
• Open Charm as a Probe of Pre-Equilibrium Dynamics in Nuclear Collisions?
• Parton Interaction Rates in the Quark-Gluon Plasma
• Gluon multiplication in high energy heavy ion collisions
• Magnetic Screening in Thermal Yang-Mills Theories
• Comment on ``Damping of energetic gluons and quarks in high-temperature QCD''
• Multiplicities for LHC Nuclear Collisions Using HERA Structure Functions
• Cancellation of Infrared Divergences in Thermal QED

Cited by in corpus (22)

• Thermalization of gluons in ultrarelativistic heavy ion collisions by including three-body interactions in a parton cascade
• Dynamics of Hot Bulk QCD Matter: from the Quark-Gluon Plasma to Hadronic Freeze-Out
• Dissipative Hydrodynamics and Heavy Ion Collisions
• Global quark polarization in non-central $A+A$ collisions
• Thermal and Chemical Equilibration in Relativistic Heavy Ion Collisions
• From colored glass condensate to gluon plasma: equilibration in high energy heavy ion collisions
• Equilibration of the Gluon-Minijet Plasma at RHIC and LHC
• Jet quenching and broadening: the transport coefficient $\hat{q}$ in an anisotropic plasma
• Stress Tensor and Bulk Viscosity in Relativistic Nuclear Collisions
• Global polarization effect and spin-orbit coupling in strong interaction
• alpha_s dependence in the equilibration in relativistic heavy ion collisions
• Dynamical Screening and Radiative Parton Energy Loss in a Quark-gluon Plasma
• A general derivation of differential cross section in quark-quark scatterings at fixed impact parameter
• Kinetic equilibration in heavy ion collisions: the role of elastic processes
• How Perfect a Gluon Plasma Can Be in Perturbative QCD?
• Global polarization of QGP in non-central heavy ion collisions at high energies
• Shear and Bulk Viscosities of a Gluon Plasma in Perturbative QCD: Comparison of Different Treatments for the gg<->ggg Process
• Closed-Time Path Integral Formalism and Medium Effects of Non-Equilibrium QCD Matter
• Screening and antiscreening in anisotropic QED and QCD plasmas
• Infrared Behaviour of The Gluon Propagator in Non-Equilibrium Situations
• Partonic Scattering Cross Sections in the QCD Medium
• A random walk with heavy flavours