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Related papers: Shear Viscosity to Entropy within a Parton Cascade

200 papers

Shear viscosity is a crucial property of QCD matter which determines the collective behavior of the the quark-gluon plasma (QGP) in ultrarelativistic heavy-ion collisions. Extending the near-equilibrium, high-precision investigations in…

High Energy Physics - Phenomenology · Physics 2021-02-03 Michael F. Wondrak , Matthias Kaminski , Marcus Bleicher

Event anisotropy measurements at RHIC suggest the strongly interacting matter created in heavy ion collisions flows with very little shear viscosity. Precise determination of "shear viscosity-to-entropy" ratio is currently a subject of…

Nuclear Experiment · Physics 2019-08-13 Monika Sharma

We consider QCD at temperatures T near Tc, where the theory deconfines. We distinguish between a "complete" Quark Gluon Plasma (QGP), where the vacuum expectation value of the renormalized Polyakov loop is near unity, essentially constant…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yoshimasa Hidaka , Robert D. Pisarski

The recent experimental CMS and E-by-E ATLAS data on the elliptic anisotropy of particles in \PbPb collisions are used to extract parton medium cross-section and the quark-gluon plasma viscosity-to-entropy ratio within the incomplete…

High Energy Physics - Phenomenology · Physics 2015-10-28 V. L. Korotkikh , E. E. Zabrodin

We use the Chapman-Enskog method to investigate the shear viscosity of the quark-gluon plasma with a focus on its relation to parton cross sections. We use the recently obtained analytical expression for the shear viscosity $\eta$ of a…

Nuclear Theory · Physics 2026-04-29 Okey Ohanaka , Zi-Wei Lin

We study the shear mode in the gauge/gravity correspondence at finite temperature. First, we confirm the general formula for the shear viscosity in an arbitrary background metric which includes a black hole in the fifth dimension. We then…

High Energy Physics - Theory · Physics 2008-11-26 J. I. Kapusta , T. Springer

In liquid helium 4, many features associated to Bose statistics have been masked by the strongly interacting nature of the liquid. As an example of these features, we examine the shear viscosity of liquid helium 4 above the lambda point.…

Superconductivity · Physics 2007-12-27 Shun-ichiro Koh

We have evaluated the shear viscosity of pion gas taking into account its scattering with the low mass resonances, $\sigma$ and $\rho$ during propagation in the medium. The thermal width (or collisional rate) of the pions is calculated from…

Nuclear Theory · Physics 2014-04-08 Sabyasachi Ghosh , Gastão Krein , Sourav Sarkar

We discuss recent applications of the partonic pQCD based cascade model BAMPS with focus on heavy-ion phenomeneology in hard and soft momentum range. The nuclear modification factor as well as elliptic flow are calculated in BAMPS for RHIC…

High Energy Physics - Phenomenology · Physics 2015-06-05 Ioannis Bouras , Andrej El , Oliver Fochler , Felix Reining , Florian Senzel , Jan Uphoff , Christian Wesp , Zhe Xu , Carsten Greiner

Using Grad's method, we calculate the entropy production and derive a formula for the second-order shear viscosity coefficient in a one-dimensionally expanding particle system, which can also be considered out of chemical equilibrium. For a…

High Energy Physics - Phenomenology · Physics 2010-04-21 Andrej El , Zhe Xu , Carsten Greiner , Azwinndini Muronga

In the dynamics of the QCD critical point, the net-baryon fluid, linked to the slow component of the order parameter, relaxes to a 3d Ising system in equilibrium. An analytical study of shear and bulk viscosity, with constraints imposed by…

Nuclear Theory · Physics 2017-11-29 N. G. Antoniou , F. K. Diakonos , A. S. Kapoyannis

Within a Boltzmann transport model, we demonstrate correlation between stopping observables and shear viscosity in central nuclear collisions at intermediate energies (on the order of 10 to 1000 MeV/nucleon). The correlation allows us to…

Nuclear Theory · Physics 2019-03-27 Brent Barker , Pawel Danielewicz

I give a physical explanation of what shear viscosity is, and what physics determines its value. Then I explain why determining the shear viscosity of the Quark-Gluon Plasma is interesting. I outline the leading-order calculation of the QGP…

High Energy Physics - Phenomenology · Physics 2017-08-23 Guy D. Moore

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…

High Energy Physics - Phenomenology · Physics 2016-01-01 O. Moroz

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

I review the recent progress made in calculating shear and bulk viscosity on the lattice, and discuss ways to improve the calculation.

High Energy Physics - Lattice · Physics 2009-01-14 Harvey B. Meyer

We determine the shear viscosity of the ultracold Fermi gas at unitarity in the normal phase using hydrodynamic expansion data. The analysis is based on a generalized fluid dynamic framework which ensures a smooth transition between the…

Quantum Gases · Physics 2017-08-16 Marcus Bluhm , Jiaxun Hou , Thomas Schaefer

The phonon contribution to the shear viscosity $\eta$ in superfluid neutron stars is calculated by assuming neutron pairing in a $^1S_0$ channel. The shear viscosity is obtained by means of variational methods for the solution of the…

High Energy Astrophysical Phenomena · Physics 2012-06-19 Laura Tolos , Cristina Manuel

We calculate the ratio of shear viscosity to entropy density for charged black branes in third order Lovelock theory. For chargeless black branes, the result turns out to be consistent with the prediction made in $\rm arXiv:0808.3498[\rm…

High Energy Physics - Theory · Physics 2009-11-17 Xian-Hui Ge , Sang-Jin Sin , Shao-Feng Wu , Guo-Hong Yang

We interpret as shear viscosity the anisotropic pressure that emerges in inhomogeneous spherically symmetric spacetimes described by the Lemaitre-Tolman-Bondi (LTB) metric in a comoving frame. By assuming that local isotropic pressure and…

General Relativity and Quantum Cosmology · Physics 2008-12-24 Roberto A Sussman