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Related papers: Suppression of the Shear Viscosity in a "semi" Qua…

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Through model-to-data comparisons from heavy-ion collisions, it has been shown that the Quark Gluon Plasma has an extremely small shear viscosity at vanishing densities. At large baryon densities, significantly less is known about the…

High Energy Physics - Phenomenology · Physics 2025-06-12 Isabella Danhoni , Jordi Salinas San Martin , Jacquelyn Noronha-Hostler

We investigate the influence of a temperature-dependent shear viscosity over entropy density ratio eta/s on the transverse momentum spectra and elliptic flow of hadrons in ultrarelativistic heavy-ion collisions. We find that the elliptic…

Nuclear Theory · Physics 2011-06-27 Harri Niemi , Gabriel S. Denicol , Pasi Huovinen , Etele Molnar , Dirk H. Rischke

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…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Majumder , B. Müller , X. -N. Wang

Current experiments at the Relativistic Heavy Ion Collider (RHIC) are probing finite baryon densities where the shear viscosity to enthalpy ratio $\eta T/w$ of the Quark Gluon Plasma remains unknown. We use the Hadron Resonance Gas (HRG)…

We investigate the shear viscosity of leptons in a strongly coupled quark gluon plasma (QGP). We find that the shear viscosity due to the lepton-quark scattering is inversely proportional to the ratio of electric conductivity of the QGP to…

High Energy Physics - Theory · Physics 2015-06-17 Berndt Müller , Di-Lun Yang

We study the effect of shear and bulk viscosities on the heavy quark transport coefficient within the matrix model of semi QGP. Dissipative effects are incorporated through the first-order viscous correction in the quark/antiquark and gluon…

High Energy Physics - Phenomenology · Physics 2020-03-25 Balbeer Singh , Hiranmaya Mishra

A synthesis of Polyakov loop models of the deconfinement transition and quasiparticle models of gluon plasma thermodynamics leads to a class of models in which gluon quasiparticles move in a non-trivial Polyakov loop background. These…

High Energy Physics - Phenomenology · Physics 2009-11-10 Peter N. Meisinger , Michael C. Ogilvie , Travis R. Miller

We investigate the temperature dependence of the shear viscosity ($\eta$) and bulk viscosity ($\zeta$) of the gluon plasma using lattice QCD over the range 0.76--2.25$\,T_c$, extending from below the transition temperature $T_c$ across the…

High Energy Physics - Lattice · Physics 2026-04-08 Heng-Tong Ding , Hai-Tao Shu , Cheng Zhang

The viscosity of the Quark-Gluon Plasma (QGP) is usually described holographically by the entropy-normalized dynamic viscosity $\eta/s$. However, other measures of viscosity, such as the kinematic viscosity $\nu$ and the Reynolds number…

High Energy Physics - Theory · Physics 2017-06-07 Brett McInnes

The transport properties of the quark gluon plasma (QGP) are studied in a QCD medium at finite temperature and chemical potential. We calculate the shear viscosity $\eta(T,\mu_q)$ and the electric conductivity $\sigma_e(T,\mu_q)$ for a…

High Energy Physics - Phenomenology · Physics 2015-06-11 Hamza Berrehrah , Elena Bratkovskaya , Wolfgang Cassing , Rudy Marty

We compute the collisional energy loss for a heavy quark above the critical temperature in Quantum ChromoDynamics (QCD). We work in the semi Quark-Gluon Plasma, which assumes that this region is dominated by the non-trivial holonomy of the…

High Energy Physics - Phenomenology · Physics 2015-06-18 Shu Lin , Robert D. Pisarski , Vladimir V. Skokov

In recent years, there has been a significant effort to extract the temperature-dependent shear ($\eta/s$) and bulk ($\zeta/s$) viscosity over entropy ratios of the quark-gluon plasma from a global comparison of heavy-ion data with results…

Nuclear Theory · Physics 2023-02-28 Fernando G. Gardim , Jean-Yves Ollitrault

We compute the shear viscosity of two-flavor QCD plasma in an external magnetic field in perturbative QCD at leading log order, assuming that the magnetic field is weak or soft: $eB\sim g^4\log(1/g)T^2$. We show that the shear viscosity…

High Energy Physics - Phenomenology · Physics 2018-04-04 Shiyong Li , Ho-Ung Yee

We calculate the shear viscosity $\eta$ to entropy density $s$ ratio $\eta /s$ of a gluon plasma in kinetic theory including the gg->gg and gg<->ggg processes. Due to the suppressed contribution to $\eta$ in the gg->gg forward scattering,…

Nuclear Theory · Physics 2010-03-02 Jiunn-Wei Chen , Hui Dong , Kazuaki Ohnishi , Qun Wang

We propose a theoretical model of quark-gluon plasma (QGP) produced at the Brookhaven National Laboratory (BNL) Relativistic Heavy Ion Collider (RHIC). In this model, we hypothesize that the gas of quarks and gluons are confined within the…

General Physics · Physics 2024-01-31 Yusuke Kimura

We study the Hall viscosity of the quark gluon plasma (QGP) created in non-central heavy-ion collisions. In the presence of a strong magnetic field or vorticity, rotational symmetry is broken from O(3) to O(2), allowing for two independent…

Nuclear Theory · Physics 2026-04-01 Sukrut Mondkar , Giorgio Torrieri , Matthias Kaminski , René Meyer

Ultrarelativistic heavy-ion collisions at the Relativistic Heavy-Ion Collider (RHIC) are thought to have produced a state of matter called the Quark-Gluon-Plasma, characterized by a very small shear viscosity to entropy density ratio…

Nuclear Theory · Physics 2010-04-21 Nasser Demir , Steffen A. Bass

We study the viscosity and thermodynamic properties of QGP at RHIC by employing the recently extracted equilibrium distribution functions from two hot QCD equations of state of $O(g^5)$ and $O(g^6\ln(1/g))$ respectively. After obtaining the…

Nuclear Theory · Physics 2011-07-19 Vinod Chandra , V. Ravishankar

We propose a method for extracting the shear viscosity over entropy density ratio (eta/s) of the quark-gluon plasma from experimental data. We argue that uncertainty due to poor knowledge of the earliest stages of a heavy-ion collision is…

Nuclear Theory · Physics 2013-05-14 Matthew Luzum , Jean-Yves Ollitrault

We consider the thermal production of dileptons and photons at temperatures above the critical temperature in QCD. We use a model where color excitations are suppressed by a small value of the Polyakov loop, the semi Quark-Gluon Plasma…

High Energy Physics - Phenomenology · Physics 2015-03-05 C. Gale , Y. Hidaka , S. Jeon , S. Lin , J. -F. Paquet , R. D. Pisarski , D. Satow , V. V. Skokov , G. Vujanovic