Speaker
Description
The MAJORANA DEMONSTRATOR is an ultra-low background experiment operating on the 4850’
ulevel of the Sandford Underground Research Facility in South Dakota, which operates an
array of p-type point contact (PPC) high-purity germanium (HPGe) detectors made of both
natural materials as well as materials enriched in $^{76}$Ge. The surface exposure time of MAJORANA
enriched detectors was minimized to reduce cosmogenic activation and backgrounds at low
energy. The experiment has been collecting data since 2015 and the analysis energy threshold
has been established on the order of a keV, which allows a wide range of rare event searches,
such as bosonic dark matter, solar axions and lightly ionizing particles, to probe new physics
beyond the Standard Model. Recent efforts to filter the electronic noise and to understand
the observed backgrounds at those energies, along with accumulated larger datasets, have
made it possible to set tighter limits on several of these rare event searches. To improve those
limits, new methods to assess the efficiency of selecting physics events have also been
developed. In this talk, I will present the current status, new analysis methods, and the latest
results of the MAJORANA low energy program.
