Viscous hydrodynamics description of $\phi$ meson production in Au+Au and Cu+Cu collisions

TL;DR

This paper uses viscous hydrodynamics to simulate $$ meson production in heavy-ion collisions, successfully matching experimental data and exploring the effects of viscosity and initial conditions.

Contribution

It applies Israel-Stewart second-order viscous hydrodynamics to describe $$ production in Au+Au and Cu+Cu collisions, providing insights into viscosity effects.

Findings

Viscosity over entropy ratio $/s=0.25$ explains experimental data.

Hydrodynamic model reproduces $$ multiplicity and flow observables.

Initial energy densities are estimated for different collision systems.

Abstract

In the Israel-Stewart's theory of 2nd order dissipative hydrodynamics, we have simulated $\phi$ production in Au+Au and Cu+Cu collisions at $\sqrt{s}_{NN}$=200 GeV. Evolution of QGP fluid with viscosity over the entropy ratio $\eta/s$=0.25, thermalised at $\tau_i$=0.2 fm, with initial energy density $\epsilon_i$=5.1 $GeV/fm^3$ explains the experimental data on $\phi$ multiplicity, integrated $v_2$, mean $p_T$, $p_T$ spectra and elliptic flow in central and mid-central Au+Au collisions. $\eta/s$=0.25 is also consistent with centrality dependence of $\phi$ $p_T$ spectra in Cu+Cu collisions. The central energy density in Cu+Cu collisions is $\epsilon_i$=3.48 $GeV/fm^3$.