THE EFFECT OF INTENSE ELECTROMAGNETIC-FIELDS WITH COMPLEX CONFIGURATION ON NUCLEAR BETADECAY

This paper discusses how an electromagnetic held consisting of a super position of a constant magnetic field and a field of laser type can af fect nuclear beta decay. In general it is not assumed that the intensi ties of the two types of fields are small compared to the characterist ic field H-cr=beta(1)H(cr), where H-cr=m(2)c(3)/e (h) over bar and th e quantity beta(1) depends on the energy liberated in the decay and th e configuration of the electromagnetic field. For nonrelativistic deca ys the quantity beta(1) is found to be of the same order as the maximu m kinetic energy of an electron referenced to its rest energy beta(1) similar to I much less than 1. It is assumed that the frequency of the wave field satisfies (h) over bar omega/mc(2) less than or equal to 1 . The behavior of the probability for the process is studied over a wi de range of the fundamental parameters that characterize the fields. C orresponding asymptotic expressions are derived in the ''weak''- and ' 'strong''-field regimes. Also discussed are so-called interference cor rections to the unperturbed decay probability, which cannot in princip le be studied by the methods of perturbation theory. It is shown that the times and distances that are important in generating these contrib utions exceed the parameters of tile unperturbed processes, just as in the case of a plane-wave field previously investigated in detail by N ikishov and Ritus. However, in contrast to the case of a pure wave fie ld, when a system is simultaneously subjected to a constant magnetic f ield and a wave field, the degree to which these characteristic region s are enlarged can depend not only on the intensities of the electroma gnetic fields but also on their rates of change, even in the limit in which the wave field is slowly varying. (C) 1997 American Institute of Physics.