Effects of initial-state nucleon shadowing on the elliptic flow of thermal photons

Abstract

Recently the effect of nucleon shadowing on the Monte-Carlo Glauber initial condition was studied and its role on the centrality dependence of elliptic flow (v2) and fluctuations in initial eccentricity for different colliding nuclei were explored. It was found that the results with shadowing effects are closer to the QCD based dynamical model as well as to the experimental data. Inspired by this outcome, in this work we study the transverse momentum (pT ) spectra and elliptic flow of thermal photons for Au+Au collisions at RHIC and Pb+Pb collisions at LHC by incorporating the shadowing effects in deducing the initial energy density profile required to solve the relativistic hydrodynamical equations. We find that the thermal photon spectra remain almost unaltered, however, the elliptic flow of photon is found to be enhanced significantly due to shadowing effects.

Dilepton production and elliptic flow from an anisotropic quark-gluon plasma

“…In particular, real photons produced in heavy-ion collisions can be emitted from different sources and stages and are affected by various characteristics of the QCD matter . In recent years, phenomenological studies of photon emission using hydrodynamic modeling of heavy-ion collisions have been developing [51][52][53][54][55][56][57][58][59][60][61] towards connecting theoretical ideas to experimental data. However, simultaneous quantitative description of photon yield and flow coefficients has been challenging [6].…”

Anisotropic flow of photons in relativistic heavy ion collisions

“…Motivated by these observations, photon spectra and anisotropic flow parameters are calculated by including the shadowing effect in an event-by-event hydrodynamical model framework [132].…”

“…The main advantage of studying direct photon observables in heavy ion collisions is that their emission is quite sensitive to the initial state of the produced matter [12]. As a result, even a slight change in the initial conditions would result in significant change in the final state photon observables [13][14][15][16][17][18].…”

“…Figure33. Elliptic flow of thermal photons using shadowed Glauber model initial conditions from Au+Au collisions at RHIC[132].…”

Photon production and elliptic flow from a momentum-anisotropic quark-gluon plasma

“…In particular, real photons produced in heavyion collisions can be emitted from different sources and stages and are affected by various characteristics of the QCD matter . In recent years, phenomenological studies of photon emission using hydrodynamic modeling of heavy-ion collisions have been developing [52][53][54][55][56][57][58][59][60][61][62] toward connecting theoretical ideas to experimental data. However, a simultaneous quantitative description of photon yield and flow coefficients has been challenging [6].…”