ABSTRACT: TBN
The 2013 Tom W. Bonner Prize was awarded for the first direct observation of two-neutrino double beta (bb) decay – a celebrated milestone on the path to today’s quest for the zero-neutrino mode. The cited result occurred in 1987 here on the UCI campus, in Rowland Hall. The drama that played out in that basement laboratory over the preceding 15 years remained largely out of sight. I will shine a light on that discovery process, its stumbles and its victories, influenced by interactions both positive and negative with a number of well-known contemporaries.
The power of the bb decay process to elucidate fundamental neutrino properties was recognized in the 1930’s, but the decay is exceedingly rare and difficult to detect. Unsuccessful laboratory searches had been going on for 25 years when the UCI group began is first experiment with a cloud chamber in 1972.
After some background for the non-expert, and a snapshot of the theoretical and experimental milieu at the time, the talk will begin with the reasons for choosing a cloud chamber, and the exploitation of this primitive device. The talk will end with the first definitive detection in a far-more-friendly time-projection chamber, of 2n bb decay in selenium-82.