Related papers: Viscosity coefficients for hadron and quark-gluon …
In the hadronic phase, the dominant configuration of QCD with two flavors of massless quarks is a gas of massless pions. We calculate the bulk viscosity (zeta) using the Boltzmann equation with the kinetic theory generalized to incorporate…
The ratio of bulk to shear viscosity is expected to exhibit a different behaviour in weakly and in strongly coupled systems. This can be expressed by its dependence on the squared sound velocity. In the high temperature QCD plasma at small…
We use the excluded volume Hadron Resonance Gas (HRG) model with the most up-to-date hadron list to calculate $\eta T/w$ at low temperatures and at finite baryon densities $\rho_B$. This $\eta T/w$ is then matched to a QCD-based shear…
In the Beam Energy Scan phase II (BES-II) experiments at RHIC STAR, the quark-gluon plasma (QGP) produced with changing collision energies may probe different regions of the QCD phase diagram. Correspondingly, studying the transport…
We study the shear and bulk viscosities of partonic and hadronic matter as functions of temperature T within the parton-hadron-string dynamics (PHSD) off-shell transport approach. Dynamical hadronic and partonic systems in equilibrium are…
Shear viscosity (eta) of QCD in the hadronic phase is computed by the coupled Boltzmann equations of pions and nucleons in low temperatures and low baryon number densities. The eta to entropy density ratio eta/s maps out the nuclear…
The bulk and shear viscosities ($\eta$ and $\zeta$) have been studied for quark-gluon-plasma produced in relativistic heavy ion collisions within semi-classical transport theory, in a recently proposed quasi-particle model of (2+1)-flavor…
We derive an expression relating the transport parameter $\hat{q}$ and the shear viscosity $\eta$ of a weakly coupled quark-gluon plasma. A deviation from this relation can be regarded as a quantitative measure of ``strong coupling'' of the…
We present calculations for the shear viscosity of the hot and dense quark-gluon plasma (QGP) using the partonic scattering cross sections as a function of temperature $T$ and baryon chemical potential $\mu_B$ from the dynamical…
The shear $\eta$ and bulk $\zeta$ viscous coefficients have been calculated in a hot and chirally asymmetric quark matter quantified in terms of a chiral chemical potential (CCP) using the two-flavor Nambu-Jona--Lasinio (NJL) model. This is…
Numerical results for the transport coefficients of quark gluon plasma are calculated by lattice simulation of SU(3) pure gauge model. The bulk viscosity is consistent with zero. The shear viscosity is finite and increases with temperature…
One of the most remarkable features of the Quark Gluon Plasma is its nearly perfect fluidity behavior indicated by the small shear viscosity to entropy density ratio obtained from fitting relativistic viscous hydrodynamics flow harmonics to…
In this study, we analyze the transport properties of the Quark-Gluon Plasma, focusing on bulk ($\zeta$) and shear ($\eta$) viscosities at vanishing chemical potential. To describe the QGP, we employ a quasiparticle model for quarks along…
We concentrate on calculation of the shear and bulk viscosities of the hadron gas. They define its dissipative dynamics and influence its experimentally measurable elliptic flow. Due to difficulty of this calculation the relaxation time…
Based on the kinetic theory with relaxation time approximation, we investigate the bulk viscosity ($\zeta$) and its ratio to shear viscosity ($\zeta/\eta$) of quark matter at finite temperature and chemical potential with the in-medium…
Employing new precision data of the equation of state of the SU(3) Yang-Mills theory (gluon plasma) the dilaton potential of a gravity-dual model is adjusted in the temperature range $(1 - 10) T_c$ within a bottom-up approach. The ratio of…
Due to their weak final state interactions, the $\phi$ meson and $\Omega$ baryon provide unique probes of the properties of the quark-gluon plasma (QGP) formed in relativistic heavy-ion collisions. Using the quark recombination model with…
Among the key features of hot and dense QCD matter produced in ultra-relativistic heavy-ion collisions at RHIC is its very low shear viscosity, indicative of the properties of a near-ideal fluid, and a large opacity demonstrated by jet…
The new state of matter produced at Relativistic Heavy Ion Collider reveals a strongly coupled quark-gluon plasma with an extremely small shear viscosity to entropy density ratio eta/s. We calculate the eta/s of an equilibrated hadron…
The shear viscosity of quark gluon plasma is customarily estimated in the literature using kinetic theory, which, however, is well known to break down for dense interacting systems. Here we propose an alternative theoretical approach based…