Quasiparticle anisotropic hydrodynamics

TL;DR

This paper compares quasiparticle anisotropic hydrodynamics with standard methods in modeling quark-gluon plasma, highlighting their agreement at low viscosity and differences at high viscosity, especially in particle spectra predictions.

Contribution

It introduces a quasiparticle anisotropic hydrodynamics framework and compares its predictions with standard anisotropic and viscous hydrodynamics methods.

Findings

All methods agree at low shear viscosity to entropy density ratio.

Differences emerge at high shear viscosity, affecting particle spectra.

Standard anisotropic hydrodynamics shows suppressed low-$p_T$ production.

Abstract

We study an azimuthally-symmetric boost-invariant quark-gluon plasma using quasiparticle anisotropic hydrodynamics including the effects of both shear and bulk viscosities. We compare results obtained using the quasiparticle method with the standard anisotropic hydrodynamics and viscous hydrodynamics. We consider the predictions of the three methods for the differential particle spectra and mean transverse momentum. We find that the three methods agree for small shear viscosity to entropy density ratio, $\eta/s$, but show differences at large $\eta/s$. Additionally, we find that the standard anisotropic hydrodynamics method shows suppressed production at low transverse-momentum compared to the other two methods, and the bulk-viscous correction can drive the primordial particle spectra negative at large $p_T$ in viscous hydrodynamics.