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arXiv · 1403.7558

Thermal photon anisotropic flow serves as a quark-gluon plasma viscometer

Chun Shen·Ulrich Heinz·Jean-Francois Paquet·Charles Gale
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Abstract

Photons are a penetrating probe of the hot and dense medium created in heavy-ion collisions. We present state-of-the-art calculations of viscous photon emission from nuclear collisions at RHIC and LHC. Thermal photons anisotropic flow coefficients v_n are computed, both with and without accounting for viscous corrections to the standard thermal emission rates. These corrections are found to have a larger effect on the v_n coefficients than the viscous suppression of hydrodynamic flow anisotropies. For thermal photons, the ratio v_2{SP}/v_3{SP} shows stronger sensitivity to the quark-gluon plasma (QGP) shear viscosity than for hadrons, and it can thus serve as a sensitive QGP viscometer.

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Chun Shen, Ulrich Heinz, Jean-Francois Paquet, Charles Gale. 2014-03-28. Thermal photon anisotropic flow serves as a quark-gluon plasma viscometer. https://doi.org/10.1016/j.nuclphysa.2014.07.042

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