The KamLAND-Zen experiment is one of the most sensitive experiments investigating the Majorana nature of neutrinos through neutrinoless double-beta decay. The KamLAND-Zen collaboration recently reported the most stringent limits on the neutrinoless double-beta decay half-life in Xe-136 with almost one tonne-year of exposure. Interpreting this half-life in the standard light neutrino mechanism and using a range of commonly adopted nuclear matrix elements, results in an upper limit on the effective Majorana neutrino mass of 36-156 meV, where the lower boundary enters the so-called Inverted Mass Ordering of neutrinos. The high sensitivity of the experiment required new insights into backgrounds, especially from cosmic muon spallation of xenon, and novel background rejection techniques. I will describe the upgraded KamLAND-Zen detector, the data analysis and our new results.
https://arxiv.org/abs/2203.02139
Join from PC, Mac, Linux, iOS or Android: https://stanford.zoom.us/j/98973156241?pwd=cEU5RFdlVXoyc0JTeTlDMkozKzQ5UT09
Federico Bianchini, Sander Breur
(fbianc@slac, sanderb@slac)
