Final Results of the Majorana Demonstrator’s Search for Double-Beta Decay of ⁷⁶Ge to Excited States of ⁷⁶Se

Author(s)

• I. J. Arnquist
• Frank Avignone III, University of South CarolinaFollow
• A. S. Barabash
• E. Blalock
• B. Bos
• M. Busch
• Y. -D. Chan
• J. R. Chapman
• C. D. Chrisofferson
• et. al.
• Majorana Collaboration

Document Type

Article

Abstract

⁷⁶Ge can ββ decay into three possible excited states of ⁷⁶Se, with the emission of two or, if the neutrino is Majorana, zero neutrinos. None of these six transitions have yet been observed. The Majorana Demonstrator was designed to study ββ decay of ⁷⁶Ge using a low background array of high purity germanium detectors. With 98.2 kg·y of isotopic exposure, the demonstrator sets the strongest half-life limits to date for all six transition modes. For 2νββ to the 0₁⁺ state of ⁷⁶Se, this search has begun to probe for the first time half-life values predicted using modern many-body nuclear theory techniques, setting a limit of T_1/2 > 1.5 × 10²⁴ y (90% CL).

Digital Object Identifier (DOI)

https://doi.org/10.1103/PhysRevLett.134.242501

Publication Info

Published in Physical Review Letters, Volume 134, 2025.

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 Internationallicense. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

APA Citation

Arnquist, I. J., Avignone, F. T., Barabash, A. S., Blalock, E., Bos, B., Busch, M., Chan, Y.-D., Chapman, J. R., Christofferson, C. D., Chu, P.-H., Cuesta, C., Detwiler, J. A., Efremenko, Yu., Ejiri, H., Elliott, S. R., Fuad, N., Giovanetti, G. K., Green, M. P., Gruszko, J., … Majorana Collaboration. (2025b). Final results of the majorana demonstrator’s search for double-beta decay of GE 76 to excited states of SE 76. Physical Review Letters, 134(24), Article 242501. https://doi.org/10.1103/PhysRevLett.134.242501