Enhancement of jet quenching around phase transition: Result from the dynamical holographic model

Abstract

The phase transition and jet quenching parameter $\stackrel{^}{q}$ are investigated in the framework of the dynamical holographic QCD model. We find that both the trace anomaly and the ratio of the jet quenching parameter over cubic temperature $\stackrel{^}{q}/{T}^{3}$ show a peak around the critical temperature ${T}_{c}$, and the ratio of the jet quenching parameter over entropy density $\stackrel{^}{q}/s$ sharply rises at ${T}_{c}$. This indicates that the jet quenching parameter can characterize the phase transition. The effect of the jet quenching parameter enhancement around the phase transition on the nuclear modification factor ${R}_{AA}$ and elliptic flow ${v}_{2}$ are also analyzed, and we find that the temperature-dependent jet quenching parameter from the dynamical holographic QCD model can considerably improve the description of jet quenching azimuthal anisotropy as compared with the conformal case.