DREENA-C framework: joint RAA and v2 predictions and implications to QGP tomography

Abstract

In this paper, we presented our recently developed Dynamical Radiative and Elastic ENergy loss Approach (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 have generated, for the first time, joint RAA and v2 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. While RAA predictions agree with experimental data, v2 predictions qualitatively agree with, but are quantitatively visibly above, the experimental data (in disagreement with other models, which underestimate v2). Consistently with numerical predictions, through simple analytic analysis, we show that RAA is insensitive to medium evolution (though highly sensitive to energy loss mechanisms), while v2 is highly sensitive to the evolution. As a major consequence for precision quark-gluon plasma (QGP) tomography, this then leaves a possibility to calibrate energy loss models on RAA data, while using v2 to constrain QGP parameters that are in agreement with both high and low p⊥ data.