Direct evidence for two-neutrino double-beta decay in 82Se
Abstract
The two-neutrino mode of double-beta decay in 82Se has been observed in a time-projection chamber at a half-life of (1.1+0.8-0.3)×1020 yr (68% confidence level). This result from direct counting confirms the earlier geochemical measurements and helps provide a standard by which to test the double-beta-decay matrix elements of nuclear theory. It is the rarest natural decay process ever observed directly in the laboratory.
- Publication:
-
Physical Review Letters
- Pub Date:
- November 1987
- DOI:
- 10.1103/PhysRevLett.59.2020
- Bibcode:
- 1987PhRvL..59.2020E
- Keywords:
-
- Electron Decay Rate;
- Half Life;
- Kinetic Energy;
- Neutrinos;
- Cosmic Rays;
- Energy Spectra;
- Nuclear and High-Energy Physics;
- 23.40.Bw;
- Weak-interaction and lepton aspects