The LEGEND experiment searches for neutrinoless double beta decay in 76Ge-enriched highpurity germanium detectors operating in liquid argon, whose scintillation acts as an active veto against external background events. Using specialized detector geometries, pulse shape discrimination is performed to further veto background events. LEGEND-200 has completed about one year of stable physics data-taking at Laboratori Nazionali del Gran Sasso (LNGS) in Italy, with the first data recently unblinded. With a planned ultimate exposure of 1 ton·yr and a target background index of 2×10^−4 cts/(keV·kg·yr) at Q_ββ = 2039 keV, LEGEND-200 is expected to reach a 3σ discovery sensitivity of 10^27 years half-life. The next generation experiment, LEGEND-1000, will operate 1000 kg of detectors and reach an expected discovery sensitivity of 10^28 years half-life, covering the inverted neutrino mass hierarchy.
Biography:
Louis Varriano is a postdoc at CENPA at the University of Washington in Jason Detwiler's group working on LEGEND. His graduate work at the University of Chicago and Argonne National Laboratory focused on measurements of 8B and 8Li beta-decay angular correlations with ion traps to search for a tensor contribution to the weak interaction.