The Majorana Demonstrator: Progress Towards Showing The Feasibility Of A Tonne-Scale Ge-76 Neutrinoless Double-Beta Decay Experiment

The MAJORANA DEMONSTRATOR will search for the neutrinoless double-beta decay (0 nu beta beta) of the Ge-76 isotope with a mixed array of enriched and natural germanium detectors. The observation of this rare decay would indicate the neutrino is its own anti-particle, demonstrate that lepton number is not conserved, and provide information on the absolute mass-scale of the neutrino. The DEMONSTRATOR is being assembled at the 4850 foot level of the Sanford Underground Research Facility in Lead, South Dakota. The array will be contained in a low-background environment and surrounded by passive and active shielding. The goals for the DEMONSTRATOR are: demonstrating a background rate less than 3 t(-1) y(-1) in the 4 keV region of interest (ROT) surrounding the 2039 keV Ge-76 endpoint energy; establishing the technology required to build a tonne-scale germanium based double-beta decay experiment; testing the recent claim of observation of 0 nu beta beta [I]; and performing a direct search for light WIMPs (3-10 GeV/c(2)).