Vn. Rodionov, NUCLEAR BETA-DECAY AND PHOTOPRODUCTION OF E(-) PAIRS IN INTENSE ELECTROMAGNETIC-FIELDS WITH A COMPLEX CONFIGURATION()E(), Journal of experimental and theoretical physics, 86(1), 1998, pp. 11-23
The effect of an intense electromagnetic field formed by the superposi
tion of a constant magnetic field and a laser-type field on nuclear be
ta-decay and on pair production by two gamma-rays with different polar
izations is studied. Time integral representations are obtained for th
e total probabilities of these processes without restrictions on the s
trengths of the fields making up the configuration. Despite the differ
ent nature of these reactions, in the nonrelativistic limit these expr
essions contain similar dependences on the field characteristics and t
he differences reduce to different power-law singularities in the beha
vior of the integrands at zero. At low fields, complete asymptotic exp
ansions of the probabilities of these processes, including perturbatio
n theory terms and oscillatory field contributions, are obtained in te
rms of parameters characterizing the fields. It is shown that the osci
llatory corrections can be enhanced owing to the effect of a combinati
on external field. The analysis of the probabilities of the various pr
ocesses given here in terms of nonlinear functions of the field is ill
ustrated by numerical calculations and graphs. (C) 1998 American Insti
tute of Physics.