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The MAJORANA DEMONSTRATOR is sensitive to rare events near its energy threshold, including bosonic dark matter, solar axions, and lightly ionizing particles. In this analysis, a novel training set of low energy small-angle Compton scatter events is used to determine the efficiency of pulse shape analysis cuts, and we present updated bosonic dark matter and solar axion results from an 11.17 kg-y dataset using a 5 keV analysis threshold., Comment: 4 pages, 4 figures. Proceedings of the 16th International Conference on Topics in Astroparticle and Underground Physics (TAUP 2019), September 9-13, 2019, Toyama, Japan

The Majorana Demonstrator is an ultra-low background physics experiment searching for the neutrinoless double beta decay of $^{76}$Ge. The Majorana Parts Tracking Database is used to record the history of components used in the construction of the Demonstrator. The tracking implementation takes a novel approach based on the schema-free database technology CouchDB. Transportation, storage, and processes undergone by parts such as machining or cleaning are linked to part records. Tracking parts provides a great logistics benefit and an important quality assurance reference during construction. In addition, the location history of parts provides an estimate of their exposure to cosmic radiation. A web application for data entry and a radiation exposure calculator have been developed as tools for achieving the extreme radio-purity required for this rare decay search.

The Majorana project is a next-generation neutrinoless double-beta decay (Oνββ) experiment that will endeavor to provide evidence as to the Majorana or Dirac nature of the electron neutrino. If the neutrino is a Majorana particle, Oνββ measurements will also provide direct limits on the effective Majorana mass (mββ) of the electron neutrino. We present an overview of current plans to build a 'demonstrator module' with an active mass of ≈ 60 kg (30 kg of this will be natural germanium, and 30 kg will be enriched to 86% in 76Ge). This mass corresponds to a sensitivity to mββ ≈ 200 meV, assuming light Majorana neutrino exchange dominates as the mechanism for Oνββ. This phase of the Majorana experiment will demonstrate the background levels and experimental techniques necessary to scale up to an detector fielding an active mass of 1000 kg of 76Ge (corresponding to mββ sensitivity of ≈ 30 meV). Detector fabrication is a critical issue for performance, cost, and schedule of a 1000-kg detector array, and the collaboration is examining alternative detector technologies including both point-contact p-type and highly-segmented n-type diodes during the demonstrator phase of the experiment. We will highlight recent Majorana technical and R&D achievements and outline a path forward for construction of the demonstrator module.