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Related papers: The "minimal" viscosity and elliptic flow at RHIC

200 papers

We present the directed flow measurement ($v_1$) from Au+Au collisions at $\sqrtsNN = 62$ GeV. Over the pseudorapidity range we have studied, which covers $\eta$ from -1.2 to 1.2 and $2.4 < |\eta| < 4$, the magnitude of $v_1$ for charged…

Nuclear Experiment · Physics 2009-11-10 Aihong Tang

The eddy viscosity for a turbulent compressible fluid with a relativistic equation of state is derived. Compressibility allows for sound modes, but the eddy viscosity in the shear mode is found to be the same as for incompressible fluids.…

Nuclear Theory · Physics 2009-01-14 Paul Romatschke

We report on recent results from VISH2+1, a code that solves the relativistic Israel-Stewart equations for causal viscous hydrodynamics for heavy-ion collisions with longitudinal boost invariance. We find that even ``minimal'' shear…

Nuclear Theory · Physics 2008-11-26 Ulrich W Heinz , Huichao Song

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 show that the centrality and system-size dependence of elliptic flow measured at RHIC are fully described by a simple model based on eccentricity scaling and incomplete thermalization. We argue that the elliptic flow is at least 25%…

Nuclear Theory · Physics 2008-11-26 Hans-Joachim Drescher , Adrian Dumitru , Clement Gombeaud , Jean-Yves Ollitrault

The transport coefficients of strongly interacting matter are currently subject of intense theoretical and phenomenological studies due to their relevance for the characterization of the quark-gluon plasma produced in ultra relativistic…

High Energy Physics - Phenomenology · Physics 2015-05-05 A. Puglisi , S. Plumari , V. Greco

Recent hexadecapole (v4) and elliptic (v2) flow measurements are used to constrain estimates for the degree of local equilibrium, mean free path $\lambda$, and the viscosity to entropy density ratio (eta/s) of the plasma produced in Au+Au…

Nuclear Experiment · Physics 2009-05-29 Roy A. Lacey , Arkadij Taranenko , Rui Wei

The correlation between the elliptic flow $v_2$ scaled by the impact parameter $b$ and the shear viscosity $\eta$ as well as the specific viscosity $\eta/s$, defined as the ratio of the shear viscosity to the entropy density $s$, is…

Nuclear Theory · Physics 2014-11-21 C. L. Zhou , Y. G. Ma , D. Q. Fang , G. Q. Zhang , J. Xu , X. G. Cao , W. Q. Shen

We explore the influence of a temperature-dependent shear viscosity over entropy density ratio $\eta/s$ on the azimuthal anisotropies v_2 and v_4 of hadrons at various rapidities. We find that in Au+Au collisions at full RHIC energy,…

Nuclear Theory · Physics 2014-11-13 Etele Molnar , Hannu Holopainen , Pasi Huovinen , Harri Niemi

One of the most striking results from the Relativistic Heavy Ion Collider is the strong elliptic flow. This review summarizes what is observed and how these results are combined with reasonable theoretical assumptions to estimate the shear…

Nuclear Theory · Physics 2016-12-21 Derek A. Teaney

We study the elliptic flow coefficient v_2(eta,b) in Au+Au collisions at sqrt(s)=200 A GeV as a function of pseudorapidity eta and impact parameter b. Using a hybrid approach which combines early ideal fluid dynamical evolution with late…

Nuclear Theory · Physics 2008-11-26 Tetsufumi Hirano , Ulrich W. Heinz , Dmitri Kharzeev , Roy Lacey , Yasushi Nara

The elliptic flow ($v_{2}$) at $\sqrt{s_{\rm NN}} = $ 11.5, 39, and 200 GeV and triangular flow ($v_{3}$) at $\sqrt{s_{\rm NN}} = $ 200 GeV of identified particles ($\pi^{\pm}, K^{\pm}, K^{0}_{S}, p, \bar{p}, \phi, \Lambda$ and…

Nuclear Experiment · Physics 2015-09-28 Xu Sun , Jianli Liu , Alexander Schmah , Shusu Shi , Jingbo Zhang , Lei Huo , Hanzhi Jiang

We report recent progress on causal viscous hydrodynamics for relativistic heavy ion collisions. For fixed specific shear viscosity eta/s, uncertainties in the elliptic flow arising from initial conditions, equation of state, bulk viscosity…

Nuclear Theory · Physics 2010-01-15 Huichao Song , Ulrich W. Heinz

Effects of the bulk viscosity on the elliptic flow are studied. To introduce a realistic equation of state and transport coefficients, we apply the results of the lattice QCD and hadron resonance gas calculations for these quantities. We…

High Energy Physics - Phenomenology · Physics 2009-12-14 G. S. Denicol , T. Kodama , T. Koide , Ph. Mota

In minimum bias (0-80%) Au+Au collisions at $\sqrt{s_{NN}}$=200 GeV, the elliptic flow ($v_{2}$) measurements for di-electrons from the low to intermediate mass region are presented. The differential elliptic flow as a function of…

Nuclear Experiment · Physics 2019-08-21 Xiangli Cui

The specific shear viscosity (eta/s)_QGP of a Quark-Gluon-Plasma (QGP) at temperatures T_c < T < 2T_c is extracted from the centrality dependence of the eccentricity-scaled elliptic flow measured in ultra-relativistic heavy-ion collisions.…

Nuclear Theory · Physics 2011-05-23 Huichao Song , Steffen A. Bass , Ulrich W. Heinz , Tetsufumi Hirano , Chun Shen

In the Israel-Stewart's theory of dissipative hydrodynamics, we study the scaling properties elliptic flow in Au+Au collisions. Initial energy density of the fluid was fixed to reproduce STAR data on $\phi$ meson multiplicity in 0-5% Au+Au…

Nuclear Theory · Physics 2010-04-22 A. K. Chaudhuri

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

A new set of equations for relativistic viscous hydrodynamics that captures both weak-coupling and strong-coupling physics to second order in gradients has been developed recently. We apply this framework to bulk physics at RHIC, both for…

Nuclear Theory · Physics 2014-11-18 Matthew Luzum , Paul Romatschke

The large elliptic flow observed at RHIC is considered to be evidence for almost perfect liquid behavior of the strongly coupled quark-gluon plasma produced in the collisions. In these proceedings we present a two parameter fit for the…

Nuclear Experiment · Physics 2009-11-18 H. Masui , J-Y. Ollitrault , R. Snellings , A. Tang