Dynamical Holographic Model Research Articles

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

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.

Dynamical holographic QCD model

We develop a dynamical holographic QCD model, which resembles the renormalization group from ultraviolet (UV) to infrared (IR). The dynamical holographic model is constructed in the graviton-dilaton-scalar framework with the dilaton background field $\Phi$ and scalar field $X$ responsible for the gluodynamics and chiral dynamics, respectively. We summarize our results on hadron spectra, QCD phase transition and transport properties including the jet quenching parameter and the shear/bulk viscosity in the framework of the dynamical holographic QCD model.