• Physics and Astronomy Colloquium

August 21, 2026 3:30 PM - August 21, 2026 4:30 PM
PAIS 1100

Host:

Michael Gold

Presenter:

Jason Detwiler (Univ Washington)

The Large Enriched Germanium Experiment for Neutrinoless Double-beta decay (LEGEND) aims to be the first to observe the creation of matter without matter in the form of neutrinoless double-beta decay, an L- and (B-L)-violating ultra-rare nuclear process generically predicted by standard model extensions incorporating neutrino mass, leptogenesis, and/or other LNV physics.

I'll report recent limits on this process in 76Ge from LEGEND-200, which deploys an array of Ge crystal diodes into a liquid argon scintillation detector, reaching record half-life sensitivity for this process when combined with previous-generation HPGe searches.

LEGEND-200 continues to run at the Gran Sasso laboratory in Italy and is poised to break new ground in the coming years.

I'll also give an update on progress toward the future phase of the experiment, LEGEND-1000, which will deploy 1 ton of Ge detectors in underground-sourced liquid argon.

For most phenomenological nuclear matrix element calculations, LEGEND-1000 will have discovery sensitivity covering the entire parameter space for light neutrino exchange with inverted-ordered masses.