An improved limit on the neutrinoless double-electron capture of 36 Ar with GERDA
Research output: Contribution to journal › Research article › Contributed › peer-review
Contributors
- Chair of Nuclear Physics
- University College London
- University of Zurich
- Moscow Engineering Physics Institute
- University of Padua
- Technical University of Munich
- University of L'Aquila
- University of Tübingen
- Duke University
- Moscow Institute of Physics and Technology
Abstract
The GERmanium Detector Array (Gerda) experiment operated enriched high-purity germanium detectors in a liquid argon cryostat, which contains 0.33% of 36 Ar, a candidate isotope for the two-neutrino double-electron capture (2 ν ECEC) and therefore for the neutrinoless double-electron capture (0 ν ECEC). If detected, this process would give evidence of lepton number violation and the Majorana nature of neutrinos. In the radiative 0 ν ECEC of 36 Ar, a monochromatic photon is emitted with an energy of 429.88 keV, which may be detected by the Gerda germanium detectors. We searched for the 36 Ar 0 ν ECEC with Gerda data, with a total live time of 4.34 year (3.08 year accumulated during Gerda Phase II and 1.26 year during Gerda Phase I). No signal was found and a 90% CL lower limit on the half-life of this process was established T1 / 2> 1.5 · 10 22 year.
Details
Original language | English |
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Article number | 34 |
Journal | European Physical Journal C |
Volume | 84 |
Issue number | 1 |
Publication status | Published - Jan 2024 |
Peer-reviewed | Yes |