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Title: Search for the double-beta decay of $^{82}$Se to the excited states of $^{82}$Kr with NEMO-3
The double-beta decay of 82Se to the 0+1excited state of 82Kr has been studied with the NEMO-3 detector using 0.93kg of enriched 82Se measured for 4.75y, corresponding to an exposure of 4.42kg·y. Adedicated analysis to reconstruct the γ-rays has been performed to search for events in the 2e2γchannel. No evidence of a 2νββdecay to the 0+1state has been observed and a limit of T2ν1/2(82Se, 0+gs→0+1) >1.3 ×1021yat 90%CL has been set. Concerning the 0νββdecay to the 0+1state, alimit for this decay has been obtained with T0ν1/2(82Se, 0+gs→0+1) >2.3 ×1022yat 90%CL, independently from the 2νββdecay process. These results are obtained for the first time with a tracko-calo detector, reconstructing every particle in the final state.  more » « less
Award ID(s):
1811901
PAR ID:
10308972
Author(s) / Creator(s):
Date Published:
Journal Name:
Nuclear physics
Volume:
996
ISSN:
0375-9474
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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