Self-diffusion in granular gases
The coefficient of self-diffusion for a homogeneously cooling granular gas changes significantly if the impact-velocity dependence of the restitution coefficient epsilon is taken into account. For the case of a constant epsilon the particles spread logarithmically slowly with time, whereas a velocity-dependent coefficient yields a power law time dependence. The impact of the difference in these time dependences on the properties of a freely cooling granular gas is discussed.
Brilliantov
NV
Physics Department, Moscow State University, Moscow 119899, Russia and Humboldt-Universitat, Institut fur Physik, Invalidenstrasse 110, D-10115 Berlin, Germany.
Poschel
T