Anisotropic flow of thermal photons as a quark-gluon plasma viscometer

作者:Shen Chun*; Heinz Ulrich; Paquet Jean Francois; Kozlov Igor; Gale Charles
来源:Physical Review C, 2015, 91(2): 024908.
DOI:10.1103/PhysRevC.91.024908

摘要

We present state-of-the-art calculations of viscous photon emission from nuclear collisions at the BNL Relativistic Heavy Ion Collider (RHIC) and the CERN Large Hadron Collider (LHC). Fluctuating initial density profiles are evolved with event-by-event viscous hydrodynamics. Momentum spectra of thermal photons radiated by these explosively expanding fireballs and their p(T)-differential anisotropic flow coefficients v(n)(p(T)) are computed, both with and without accounting for viscous corrections to the standard thermal emission rates. Viscous corrections to the rates are found to have a larger effect on the v(n) coefficients than the viscous suppression of hydrodynamic flow anisotropies. The benefits of taking the ratio of elliptic to triangular flow, v(2)/v(3), are discussed, and the space-time regions that contribute dominantly to the photon flow harmonics are identified. The directed flow v(1) of thermal photons is predicted for the energies currently available at the RHIC and the LHC.

  • 出版日期2015-2-19
  • 单位McGill