Thermalization in mixtures of ultracold gases
  Starting from a set of coupled Boltzmann equations, we investigate the thermalization of a two-species cold atomic gas confined either in a box or in an isotropic harmonic trap. We show that the thermalization times, by contrast to the collision rate, depend on the interferences between scattering partial waves. The dynamics of thermalization in a harmonic trap is also strongly dependent upon the ratio between the collision rate and the trap frequencies. 
Marco Anderlini (NIST), David Guery-Odelin (LKB - Lhomond)