A status update on the {\sc Majorana Demonstrator}

ORAL

Abstract

The {\sc Majorana} Collaboration is seeking neutrinoless double-beta decay ($0\nu\beta\beta$), a lepton number violating process that would indicate that the neutrino is a Majorana fermion, in $^{76}$Ge. An array of P-type point contact (PPC) high-purity germanium (HPGe) detectors isotopically enriched in $^{76}$Ge will be used to perform this search. For inverted hierarchy neutrinos, a tonne-scale array with backgrounds of $<1$ ct/ROI-t-y in the 4 keV region of interest (ROI) around the 2039 keV Q-value for double-beta decay in $^{76}$Ge will be sensitive to $0\nu\beta\beta$ decay. In order to demonstrate the feasibility of such an experiment, the {\sc Majorana Demonstrator} is being constructed at the 4850' level of the Sanford Underground Research Facility (SURF). The {\sc Demonstrator} will consist of an array of 40 kg of PPC HPGe detectors, 30 kg of which will be enriched to $87\%$ in $^{76}$Ge, housed in two separate modular cryostats inside of a compact shield. The background goal for the {\sc Demonstrator} is $<3$ cts/ROI-t-y, which is expected to scale down to $<1$ ct/ROI-t-y for a tonne-scale experiment. This presentation will contain a status update on the {\sc Majorana Demonstrator}.

Authors

  • Ian Guinn

    Univ of Washington