Self-adjoint extensions of the Hamiltonian for a charged spin- 1/2 particle in the Aharonov-Bohm field

Recently we studied self-adjoint extensions (SAEs) of the Aharonov-Bohm Hamiltonian for a charged Schrodinger particle of spin 0. In this paper we discuss the relation between the SAEs for a spinless particle and those for a spin- 1/2 particle in the same environment. We also consider SAEs when a Coulomb potential is added. We furthermore clarify a few confusing issues which have been discussed in some recent papers regarding the relativistic Dirac particle in the Aharonov-Bohm field.