Chromodynamic Weibel instabilities in relativistic nuclear collisions

Abstract

Employing a previously derived formulation, and extending the treatment from purely transverse modes to wave vectors having a longitudinal component, we discuss the prospects for the occurrence of Weibel-type color-current filamentation in high-energy nuclear collisions. Numerical solutions of the dispersion equation for a number of scenarios relevant to RHIC and LHC suggest that modes with (predominantly transverse) wave numbers of several hundred MeV may become moderately agitated during the early collision stage. The emergence of filamentation helps to speed up the equilibration of the parton plasma and it may lead to non-statistical azimuthal patterns in the hadron final state.Comment: 11 pages, RevTex, 13 (e)ps files (revised for PRC

Shear viscosity η to electrical conductivity σel ratio for an anisotropic QGP

“…In recent years the study of anisotropic plasma has received much interest due to the fact that the QGP, which has a local momentum-space anisotropy, is subject to the chromo-Weibel instability [64,66,[68][69][70][71][72][73][74][75][76][77][78][79][80][81][82][83][84][85][86]. The effects of these instabilities are not very clear, but they are very important for the QGP evolution at the RHIC or LHC.…”

SQM 2006: theory summary and perspectives

“…Recent calculations assuming a hadronizing QGP out of chemical equilibrium with subsequent hadronic rescatting have shown that rescatting via binary collisions in the hadronic phase is insufficient to drive the system toward chemical equilibrium before the expansion of the system leads to chemical freeze-out [21]. Currently the most favored approaches for explaining the rapid thermalization of the medium are either centered around turbulent color fields [22,23,24,25,26] or multi-particle collisions (which may take place either in the deconfined or dense, confined phase of the reaction) [27,28,29,30]. A smoking gun signature for either mechanism remains yet to be established.…”

Initial singularity of the little bang

“…This instability has in fact close connections with the Weibel instabilities encountered in the physics of anisotropic plasmas [12][13][14], and it is speculated that such an instability may help the system created after heavy ion collisions reach a state of local equilibrium [15][16][17][18][19][20][21]. Whether or not such instabilities can grow to sufficient magnitude as to become as large as the classical solution is the subject of current investigations.…”