English

Rapidity distribution of photons from an anisotropic Quark-Gluon-Plasma

High Energy Physics - Phenomenology 2014-11-20 v2 Nuclear Theory

Abstract

We calculate rapidity distribution of photons due to Compton and annihilation processes from {\em Quark Gluon Plasma} (QGP) with pre-equilibrium momentum-space anisotropy. We also include contributions from hadronic matter with late stage transverse expansion. A phenomenological model has been used for the time evolution of hard momentum scale phard(τ)p_{\rm hard}(\tau) and anisotropy parameter ξ(τ)\xi(\tau). As a result of pre-equilibrium momentum-space anisotropy, we find significant modification of photons rapidity distribution. For example, with {\em fixed initial condition} (FIC) {\em free-streaming} (δ=2\delta=2) interpolating model we observe significant enhancement of photon rapidity distribution at fixed pTp_T, where as for FIC {\em collisionally-broadened} (δ=2/3\delta=2/3) interpolating model the yield increases till y1y \sim 1. Beyond that suppression is observed. With {\em fixed final multiplicity} (FFM) {\em free-streaming} interpolating model we predict enhancement of photon yield which is less than the case of FIC. Suppression is always observed for FFM {\em collisionally-broadened} interpolating model.

Keywords

Cite

@article{arxiv.0907.3607,
  title  = {Rapidity distribution of photons from an anisotropic Quark-Gluon-Plasma},
  author = {Lusaka Bhattacharya and Pradip Roy},
  journal= {arXiv preprint arXiv:0907.3607},
  year   = {2014}
}

Comments

19 pages, 18 eps figures, Accepted for publication in Physical Review C