Analytic regularization and infra-red divergences

Abstract

For the infra-red cancellation mechanism to work in the context of analytic regularization it is necessary to replace the virtual photon propagator (k2)-1 by - Gamma (z)(-k2)-z and the photon phase-space by the continuous mass distribution 2 pi integral d4k theta (ko) theta (k2)/ Gamma (1-z)(k2)z. The cancellation for charged-particle scattering in a weak external field is shown.