SPECIAL PARTICLE PHYSICS SEMINAR: Double Beta Decay, Neutrino Mass and the MAJORANA Project"

 

 

ABSTRACT:  

 

At least one neutrino has a mass of about 50 meV or larger. However, the absolute mass scale for the neutrino is unknown. Furthermore, the critical question: Is the neutrino its own antiparticle? remains unanswered. Studies of double beta decay offer hope for determining the absolute mass scale. In particular, zero-neutrino double beta decay (0nbb) can address the issues of lepton number conservation, the particle-antiparticle nature of the neutrino, and its mass.  The 0nbb half-life of a nucleus is directly related to the neutrino mass. But, due to the smallness of the neutrino mass, the half-life is very long; at least greater than 10²⁵ years. Hence any search for 0nbb must minimize the background of other processes that may take place in a detector and mask the sought-for signal. The Majorana Demonstrator will search for 0nbb in ⁷⁶Ge and is presently under construction at the Sanford Underground Research Facility in Lead, SD. This experiment will have a half-life reach beyond 10²⁶ years and is a first step toward a large experiment sensitive to neutrino masses below 50 meV.

This presentation will introduce the science of double beta decay with an emphasis on the status of the Majorana Demonstrator. 

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