Calendar Details

For more information about item submission and attendance, see About the Technical Calendar.

Tuesday, February 26

Double Beta Decay, Neutrino Mass, and
the Majorana Project

Steven R. Elliott, Los Alamos National Laboratory, Los Alamos, N.M.
Physics Division Seminar
3:00 PM — 4:00 PM, Building 6008, Conference Room
Contact: Alfredo Galindo-Uribarri (, 865.574.6124


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 (0νßß) can address the issues of lepton number conservation, the particle-antiparticle nature of the neutrino, and its mass. The 0νßß 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 0νßß 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 0νßß in Ge 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.