Recent Results from the Majorana Demonstrator

Abstract

The MAJORANA Collaboration has completed construction and is now operating an array of high purity Ge detectors searching for neutrinoless double-beta decay ($0\nu \beta \beta$) in ${}^{76}$Ge. The array, known as the MAJORANA DEMONSTRATOR, is comprised of 44 kg of Ge detectors (30 kg enriched to 88% in ${}^{76}$Ge) installed in an ultra-low background compact shield at the Sanford Underground Research Facility in Lead, South Dakota. The primary goal of the DEMONSTRATOR is to establish a low-background design that can be scaled to a next-generation tonne-scale experiment. This work reports initial background levels in the $0\nu \beta \beta$ region of interest. Also presented are recent physics results leveraging P-type point-contact detectors with sub-keV energy thresholds to search for physics beyond the Standard Model; first results from searches for bosonic dark matter, solar axions, Pauli exclusion principle violation, and electron decay have been published. Finally, this work discusses the proposed tonne-scale ${}^{76}$Ge $0\nu \beta \beta$ LEGEND experiment.

arXiv comment6 pages, 1 figure, PANIC 2017: 21st Particles and Nuclei International Conference

References in corpus (16)

• Status and Future of Nuclear Matrix Elements for Neutrinoless Double-Beta Decay: A Review
• Theory of neutrinoless double beta decay
• Background free search for neutrinoless double beta decay with GERDA Phase II
• The Large Enriched Germanium Experiment for Neutrinoless Double Beta Decay (LEGEND)
• The Majorana Demonstrator Radioassay Program
• New limits on Bosonic Dark Matter, Solar Axions, Pauli Exclusion Principle Violation, and Electron Decay from the Majorana Demonstrator
• First Limit on the Direct Detection of Lightly Ionizing Particles for Electric Charge as Low as $e$/1000 with the \textsc{Majorana Demonstrator}
• The Sanford Underground Research Facility at Homestake
• The Processing of Enriched Germanium for the MAJORANA DEMONSTRATOR and R&D for a Possible Future Ton-Scale Ge-76 Double-Beta Decay Experiment
• Initial Results from the MAJORANA DEMONSTRATOR
• The Majorana Demonstrator calibration system
• Background model for the MAJORANA DEMONSTRATOR
• Delayed charge recovery discrimination of passivated surface alpha events in P-type point-contact detectors
• The Status and Initial Results of the MAJORANA DEMONSTRATOR Experiment
• Spectral analysis for the Majorana Demonstrator experiment
• Design improvements to cables and connectors in the Majorana Demonstrator

Cited by in corpus (3)

• Viable low-scale model with Universal and Inverse Seesaw Mechanisms
• Benchmark neutrinoless double-beta decay matrix elements in a light nucleus
• Low scale type I seesaw model for lepton masses and mixings