Double Beta Decay Appears To Confirm Existing Theory

A long and careful search for double beta decay (simultaneous emission of two electrons) appears to confirm that leptons are conserved. C. S. Wu, R. K. Bardin, P. J. Gollon and J. D. Ullman of Columbia have found 69 events that may be the kind expected if leptons are conserved—that is, events in which two electrons are emitted with two neutrinos. Meanwhile, in 1100 hours of observation, they found only one event that might be a double beta decay without neutrinos.