[Triumf-seminars] TRIUMF Seminar today at 14:00

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Date/Time: Thu 2009-10-22 at 14:00

Location:  Auditorium          

Speaker:   Giorgio Gratta (Stanford University)

Title:     How much does a neutrino weigh? Double-beta decay and the quest for Neutrino Masses

Abstract: 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 10^25 years (or 10^15 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.

Stimulants available 15 minutes before the talk.

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