Causality bounds in charged-particle scattering
Sebastian König (Bonn)
In quantum systems with short-range interactions, causality imposes nontrivial contraints on low-energy scattering parameters. Most prominently, there exists an upper bound on the effective range parameter that was first derived for the S-wave case by Wigner and has recently been generalized to arbitrary angular momenta and an arbitrary number of spatial dimensions. In this work, we discuss the causality constraints for the situation where a Coulomb potential is present in addition to the short-range interaction and derive an upper bound for the Coulomb-modified effective range parameter in the scattering of charged particles.