Abstract
From data accumulated over 6140 h with 172 g of enriched molybdenum (1.18 mol yr of ) with the NEMO 2 detector in the Fréjus Underground Laboratory, a clear ββ2ν signal (1433 events) is observed, leading to a half-life =0.95±0.04(stat)±0.09(syst) yr. The experimental two-electron energy spectrum and the two-electron angular distribution are in agreement with the expected ones. Limits for ββ0ν decays to the ground state, excited states ( and ), and also with Majoron emission are given.
- Received 29 June 1994
DOI:https://doi.org/10.1103/PhysRevD.51.2090
©1995 American Physical Society