Dirac Hamiltonian with Coulomb potential and spherically symmetric shell contact interactiona)

Abstract

Spherically symmetric Hamiltonians describing a Dirac particle in Coulomb potential combined with contact interaction on a sphere (typically, a δ-shell interaction) are constructed. The point spectrum is studied numerically for the case of scalar and vector δ shells. A comparison of two possible definitions of δ-shell coupling constants is also given.