Neutrinoless Double-Beta Decay and Axion Searches

University Of South Dakota Main Campus, Vermillion SD

Investigators

Abstract

Neutrinoless Double-Beta Decay (NLDBD) is the only experimentally viable way to probe the particle-antiparticle nature of neutrinos. If neutrinos are their own antiparticles, the empirical conservation of total lepton number will be immediately violated, which will shed light on the fundamental question of matter over anti-matter excess in the Universe. Further, NLDBD is the key to understanding the beyond Standard Model non-zero neutrino mass. A next generation NLDBD experiment will have a significant potential to observe this long-sought decay, with far reaching implications that can revolutionize our understanding of the Universe. The PI's involvement in NLDBD experiments is aligned with the state's goal of economic development and allows the state to benefit in the exciting research occurring at the Sanford Underground Research Facility (SURF). Using the USD High Performance Computing (HPC) platform to solve cutting-edge physics problems will train USD students in computation skills that are in great demand in a modern society. The planned activities will engage local communities and will leverage existing NSF infrastructure investments at USD to foster a diverse STEM workforce. This award will support research activities contributing to the operation of the Majorana Demonstrator (MJD) NLDBD experiment. It will also support R&D efforts that address critical questions for the Large Enriched Germanium Experiment for Neutrinoless Double Beta Decay (LEGEND) project, one of the proposed next generation NLDBD experiments. Research activities will include (1) support for onsite operation at SURF and offsite monitoring, and (2) search for solar axions using correlated signals from multiple detectors. The R&D efforts for the LEGEND experiment focus on developing and performing simulation studies to gain a quantitative and comprehensive understanding of muon-induced backgrounds for LEGEND. The low background in the MJD experiment also allows the search for solar axions. Axions were postulated to solve the strong charge parity problem in the nuclear force. The search for axions could deepen our understanding of the nuclear force. This award will allow competitive searches of solar axions at MJD using a method correlating signals from multiple High-Purity Ge (HPGe) detectors developed at USD. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.