Joint $R_{AA}$ and $v_2$ predictions for $Pb+Pb$ collisions at the LHC within DREENA-C framework

TL;DR

This paper introduces the DREENA-C framework for joint predictions of nuclear modification factor and elliptic flow in Pb+Pb collisions at the LHC, achieving qualitative agreement with experimental data despite certain limitations.

Contribution

The paper presents the first joint $R_{AA}$ and $v_2$ predictions using the DREENA-C framework based on dynamical energy loss formalism, without medium evolution.

Findings

Qualitative agreement with experimental $v_2$ data

Predictions are above experimental $R_{AA}$ data

Framework shows promise for understanding QCD medium

Abstract

In this paper, we presented our recently developed DREENA-C framework, which is a fully optimized computational suppression procedure based on our state-of-the-art dynamical energy loss formalism in constant temperature finite size QCD medium. With this framework, we for the first time, generated joint $R_{AA}$ and $v_2$ predictions within our dynamical energy loss formalism. The predictions are generated for both light and heavy flavor probes, and different centrality regions in $Pb+Pb$ collisions at the LHC, and compared with the available experimental data. Despite the fact that DREENA-C does not contain medium evolution (to which $v_2$ is largely sensitive) and the fact that other approaches faced difficulties in explaining $v_2$ data, we find that DREENA-C leads to qualitatively good agreement with this data, though quantitatively, the predictions are visibly above the experimental data. Intuitive explanation behind such results is presented, supporting the validity of our model, and it is expected that introduction of evolution in the ongoing improvement of DREENA framework, will lead to better joint agreement with $R_{AA}$ and $v_2$ data, and allow better understanding of the underlying QCD medium.