Two-Particle Scattering Theory for Anyons

We consider potential scattering theory of a nonrelativistic quantum mechanical 2-particle system in R² with anyon statistics. Sufficient conditions are given which guarantee the existence of Møller operators and the unitarity of the S-matrix. As examples the rotationally invariant potential well and the delta-function potential are discussed in detail. In case of a general rotationally invariant potential the angular momentum decomposition leads to a theory of Jost functions. The anyon statistics parameter gives rise to an interpolation for angular momenta analogous to the Regge trajectories for complex angular momenta. Levinson's theorem is adapted to the present context. In particular we find that in case of a zero energy resonance the statistics parameter can be determined from the scattering phase