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arXiv · 1909.12294

Non-equilibrium photons from the bottom-up thermalization scenario

Oscar Garcia-Montero
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Abstract

In this work, I calculate the $p_\perp$ resolved spectra for the three stages of the \textit{bottom-up} scenario, which are comparable to the thermal contribution, particularly at higher values of the saturation scale $Q_S^2$. Analytical solutions are obtained by including a parametrization of scaling solutions from far-from-equilibrium classical statistical lattice simulations into a small angle kinetic rate. Furthermore, a theoretically motivated ansatz is used to account for near-collinear enhancement of the low-$p_\perp$ radiation. The system is phenomenologically constrained using the charge hadron multiplicities from LHC and RHIC as in previous parametric estimates and fair agreement with the data available for photons was found. I find that for this realistic set of parameters, the contribution from the thermalizing glasma dominates the excess photons.

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Oscar Garcia-Montero. 2019-09-26. Non-equilibrium photons from the bottom-up thermalization scenario. https://arxiv.org/abs/1909.12294

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