Abstract
The KamLAND-Zen experiment has provided stringent constraints on the neutrinoless double-beta () decay half-life in using a xenon-loaded liquid scintillator. We report an improved search using an upgraded detector with almost double the amount of xenon and an ultralow radioactivity container, corresponding to an exposure of 970 kg yr of . These new data provide valuable insight into backgrounds, especially from cosmic muon spallation of xenon, and have required the use of novel background rejection techniques. We obtain a lower limit for the decay half-life of at 90% C.L., corresponding to upper limits on the effective Majorana neutrino mass of 36–156 meV using commonly adopted nuclear matrix element calculations.
- Received 4 March 2022
- Revised 10 April 2022
- Accepted 29 November 2022
DOI:https://doi.org/10.1103/PhysRevLett.130.051801
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.
Published by the American Physical Society
Physics Subject Headings (PhySH)
Viewpoint
Probing Majorana Neutrinos
Published 30 January 2023
Detecting neutrinoless double-beta decay would confirm that the neutrino is its own antiparticle. Data from the KamLAND-Zen experiment contain no strong evidence of such events, constraining neutrino properties.
See more in Physics