Speaker
Piotr Bozek
(Institute of Nuclear Physics PAN, Krakow and Rzeszow University, Poland)
Description
Reduction of the elliptic flow of charged particles
has been proposed as a measure of the shear viscosity coefficient
in the Quark Gluon Plasma. We complete these studies by introducing
independent shear and bulk viscosities in the hadronic phase of the
hydrodynamic expansion. We show that most of the effect of the reduction of
elliptic flow due to dissipation comes from the hadronic phase. Only a
combination of the charged particle elliptic flow results with the
predictions on HBT radii, spectra and identified transverse momentum elliptic
flow of identified particles (pions, protons, strange particles) indicates a
non-zero viscosity coefficient eta/s=0.16 in the QGP phase.
Quantitative estimates of QGP shear viscosity should take into account
late dissipative effects using viscous hydrodynamics in the hadronic phase
or a hadronic cascade model.
Primary author
Piotr Bozek
(Institute of Nuclear Physics PAN, Krakow and Rzeszow University, Poland)
