Stationary Scattering in the Semi-classical Limit for a Schrِdinger Operator in a Gauge Field

We study the classical limit of the stationary scattering theory for a Schrِdinger operator in a compactly supported gauge field. We show that, under suitable hypotheses on the associated classical flow, the scattering amplitude has a complete asymptotic expansion in the semi-classical parameter, and we determine the main term of this expansion.