Radiational self-polarization of electron-positron beams in an axially symmetric focusing electric field

Radiational self-polarization of an electron (positron) beam with spontaneous emission in an axially symmetric focusing electric field with a potential of the form (r)=Ur^µ is considered. The analysis is based on the solutions of the Dirac equations found in the approximation of small oscillations in the vicinity of the equilibrium radius of rotation. It is shown that the existence of self-polarization depends significantly on the structure of the field; in particular, the probability of electron transitions with spin reversal is zero when =–1.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 88–92, April, 1989.