Speaker
Ian Guinn
(University of Washington)
Description
The MAJORANA Collaboration is seeking neutrinoless double-beta decay ($0\nu\beta\beta$) using an array of P-type point contact (PPC) high-purity germanium (HPGe) detectors isotopically enriched in $^{76}$Ge. 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 MAJORANA DEMONSTRATOR is being constructed at the 4850' level of the Sanford Underground Research Facility (SURF). The 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.The background goal for the DEMONSTRATOR is $<3$ cts/ROI-t-y, which is expected to scale down to $<1$ ct/ROI-t-y for a tonne-scale experiment. A variety of strategies are employed in order to acheive such a low background, including the development of low background materials and components, clean handling of components, a compact shield, and an extensive background estimation and verification campaign. This poster will describe several examples of the use of these strategies for the MAJORANA DEMONSTRATOR.
Author
Ian Guinn
(University of Washington)
