Cavitation and thermal photon production in relativistic heavy ion collisions
Abstract
We investigate the thermal photon production-rates using one dimensional boost-invariant second order relativistic hydrodynamics to find proper time evolution of the energy density and the temperature. The effect of bulk-viscosity and non-ideal equation of state are taken into account in a manner consistent with recent lattice QCD estimates. It is shown that the \textit{non-ideal} gas equation of state i.e behaviour of the expanding plasma, which is important near the phase-transition point, can significantly slow down the hydrodynamic expansion and thereby increase the photon production-rates. Inclusion of the bulk viscosity may also have similar effect on the hydrodynamic evolution. However the effect of bulk viscosity is shown to be significantly lower than the \textit{non-ideal} gas equation of state. We also analyze the interesting phenomenon of bulk viscosity induced cavitation making the hydrodynamical description invalid. It is shown that ignoring the cavitiation phenomenon can lead to a very significant over estimation of the photon flux. It is argued that this feature could be relevant in studying signature of cavitation in relativistic heavy ion collisions.
Keywords
Cite
@article{arxiv.1005.2756,
title = {Cavitation and thermal photon production in relativistic heavy ion collisions},
author = {Jitesh R. Bhatt and Hiranmaya Mishra and V. Sreekanth},
journal= {arXiv preprint arXiv:1005.2756},
year = {2015}
}
Comments
9 pages, 11 figures, title changed, Talk given by Sreekanth V. at International School and Workshop, Dense QCD Phases in Heavy-Ion Collisions, August 21st - September 4th, 2010 JINR Dubna, Russia