Measuring initial temperature through photon to dilepton ratio in heavy ion collision

TL;DR

This paper proposes using the ratio of thermal photon to dilepton transverse momentum spectra in heavy ion collisions to reliably estimate the initial temperature, reducing uncertainties inherent in individual spectrum calculations.

Contribution

It introduces a ratio method for thermal photon and dilepton spectra that minimizes dependence on uncertain parameters in heavy ion collision models.

Findings

The photon to dilepton ratio is insensitive to certain model parameters.

The ratio provides a more stable estimate of initial temperature.

This approach reduces theoretical uncertainties in heavy ion collision analysis.

Abstract

Theoretical calculation of transverse momentum($p_T$) distribution of thermal photons and dileptons originating from ultra-relativistic heavy ion collisions suffer from several uncertainties since the evaluation of these spectra needs various inputs which are not yet known unambiguously. In the present work the ratio of the $p_T$ spectra of thermal photons to lepton pairs has been evaluated and it is shown that the ratio is insensitive to some of these parameters.