Relativistic shock waves in viscous gluon matter.
We solve the relativistic Riemann problem in viscous gluon matter employing a microscopic parton cascade. We demonstrate the transition from ideal to viscous shock waves by varying the shear viscosity to entropy density ratio eta/s from zero to infinity. We show that an eta/s ratio larger than 0.2 prevents the development of well-defined shock waves on time scales typical for ultrarelativistic heavy-ion collisions. Comparisons with viscous hydrodynamic calculations confirm our findings.
Bouras
I
I
Institut für Theoretische Physik, Johann Wolfgang Goethe-Universität, Max-von-Laue-Strasse 1, D-60438 Frankfurt am Main, Germany.
Molnár
E
E
Niemi
H
H
Xu
Z
Z
El
A
A
Fochler
O
O
Greiner
C
C
Rischke
D H
DH