Jason Detwiler, University of Washington
Monday, November 7, 2016 - 4:00pm to 5:00pm
PAA A-102
Among the known elementary matter fields, the neutrino alone can be Majorana in nature, a property implying that the two particles that we currently refer to as "neutrino" and "antineutrino" are in fact one in the same. This subtle refactoring of the universe's second-most ubiquitous particle would have far reaching implications. For one, Majorana neutrinos emerge in models of leptogenesis, one of the leading theories to explain why all of the matter in the universe wasn't annihilated by the antimatter produced along with it in the Big Bang, a cosmic asymmetry to which we owe our very existence.
Lepton-number violating Majorana neutrinos are also a generic prediction of many Grand Unification Theories that merge the strong nuclear and electroweak forces, and may provide our first glimpse of what lies beyond the Standard Model of particle physics.
The best known way to probe the nature of the neutrino is to search for neutrinoless double-beta decay, a rare nuclear process that is possible for just a handful of nuclear species. A broad international campaign is underway to hunt for this process in different nuclear systems using different experimental techniques, with strong opportunity for discovery in current- and next-generation experiments.
I will present preliminary data from the MAJORANA DEMONSTRATOR, one such effort using an array of enriched HPGe detectors at the Sanford Underground Research Facility in Lead, SD. I will give the current status and future prospects for this experimental technique, and will also touch on some of the theoretical challenges in understanding the nuclear transitions involved and some attempts to address them.
Watch a video of the colloquium here.