Double-beta decay and the quest for Neutrino Masses
Giorgio Gratta
Stanford University
With the definite evidence for neutrino oscillations collected in the last decade,
we now believe that neutrino masses are non-zero. Oscillation measurements,
however, only measure mass differences and give us little information about the
absolute values of neutrino masses.
The rare phenomenon of neutrino-less double-beta decay represents our best option
to attempt measuring very small neutrino masses. This process, if observed, would
also imply that neutrinos, unlike all other spin-1/2 particles, have only two component
wave functions and that lepton number is not a conserved quantity. Following the
well known principle that there is no free lunch in life, interesting half-lives for
neutrino-less double-beta decay exceed 1025 years (or 1015 times the age of the
Universe) making experiments rather challenging. I will describe how deep mines
and techniques borrowed from nuclear and particle physics, AMO and material science
all contribute to this quest.
Friday, March 6 at 4:00 PM
Room L211, Technological Institute
Refreshments are served at 3:30 PM
