Exact determination of the phase structure of a multi-species asymmetric exclusion process

We consider a multi-species generalization of the Asymmetric Simple Exclusi on Process on un open chain, in which particles hop with thier characterist ic hopping rates and fast particles can overtake slow ones. The number of s pecies is arbitrary and the hopping rates can be selected from a discrete o r continuous distribution. We determine exactly the phase structure of this model and show how the phase diagram of the 1-species ASEP is modified. De pending on the distribution uf hopping rates, the system can exist in a thr ee-phase regime or a high-phase regime. In the three-phase regime the phase structure is almost the same as iii the one species case, that is, there a re the low density, the high density and the maximal current phases, while in the two-phase regime there is no high-density phase.