“Searches for Lepton Number Violation via Neutrinoless Double Beta Decay in Germanium-based experiments” by Wenqin Xu (University Of South Dakota)

Date: 
Monday, December 11, 2017 - 3:00pm to 4:00pm
Series: 
HEAP Seminar

The large difference between neutrino and charged-fermion masses can be explained in the seesaw model, which requires neutrinos to be Majorana particles, i.e. fermions that are their own antiparticles. Neutrinoless double beta decay (NLDBD) is a hypothetical lepton-number-violating process that is possible only if neutrinos are Majorana particles. The discovery of this decay would unambiguously establish the Majorana nature of neutrinos and explicitly demonstrate that the total lepton number is violated. A measurement of the NLDBD rate may yield information regarding the absolute neutrino mass.

Deploying 44 kg of high-purity Ge (HPGe) detectors at the 4850' level of the Sanford Underground Research Facility in South Dakota, the MAJORANA DEMONSTRATOR (MJD) experiment is an ultra-low background experiment searching for NLDBD in Ge-76. The construction and commissioning of the experiment has completed and the data-taking has started. At the meantime, more than 200 researchers around the world, including many from the Majorana collaboration, have formed a collaboration for the Large Enriched Germanium Experiment for Neutrinoless Double Beta Decay (LEGEND). LEGEND is a discovery-capable tonne-scale experiment that will cover the inverted neutrino mass ordering region.

In this talk, I will discuss initial results from the MAJORANA DEMONSTRATOR experiment, including the lower limit on the NLDBD half-life, the observed ultra-low backgrounds and their implications for LEGEND. I will also discuss the status and ongoing R&D efforts of the LEGEND project.

Event Attachments: 
Location: 
Knudsen 4-134