Possible evidence for a time variation of the weak-interaction constant from double-beta-decay experiments

Abstract

The probabilities of the two-neutrino double-beta decay of 82Se and 96Zr in direct (counter) and geochemical experiments are compared. Relevant experimental data on 130Te are also analyzed. It is shown that the probability is systematically lower in geochemical experiments, which characterize the probability of ββ(2ν) decay about 109 yr ago. It is assumed that this can be due to a change in the weak-interaction constant with time. A series of new, precise measurements with the aid of counters and geochemical experiments is proposed.