Off‐shell scattering by Coulomb‐like potentials

We derive closed expressions for and interrelationships between off‐shell and on‐shell scattering quantities for Coulomb plus short‐range potentials. In particular we introduce off‐shell Jost states and show how the transition matrices are obtained from these states. We discuss some formulas connecting the coordinate and momentum representatives of certain quantities. For the pure Coulomb case we derive analytic expressions for the Jost state and the off‐shell Jost state for l=0 in the momentum representation.