Abstract
We calculate the pole shift of the pion up to second order in the density, considering the low-temperature expansion of the axial two-point function. To this order both absorptive and dispersive properties of pions are completely determined by two- and three-particle S-matrix elements. In particular, we show how the pole shift can be expressed in terms of these scattering amplitudes and discuss the size of corrections from three-particle collisions.

This publication has 15 references indexed in Scilit: