Helicity and the Aharonov-Bohm effect

Abstract
Conservation of helicity is applied to the scattering of relativistic electrons by an infinitely long solenoid of arbitrarily small radius (Aharonov-Bohm scattering). It is also shown that the Born approximation, which fails when applied to Aharonov-Bohm scattering in the Schrödinger equation formalism, gives correct results in the case of the Dirac equation.