Search for beta+EC and ECEC processes in 112Sn and beta beta decay of 124Sn to the excited states of 124Te

A. S. Barabash (1) , Ph. Hubert (2) , A. Nachab (2) , S. I. Konovalov (1) , I. A. Vanyushin (1) , V. I. Umatov (1)

1 ITEP - Institute of Theoretical and Experimental Physics [Moscow]
2 CENBG - Centre d'Etudes Nucléaires de Bordeaux Gradignan

Limits on beta+EC and ECEC processes in 112Sn and on beta beta decay of 124Sn to the excited states of 124Te have been obtained using a 380 cm3 HPGe detector and an external source consisting of natural tin. A limit with 90% C.L. on the 112Sn half-life of 0.92times 10 20 y for the ECEC(0nu) transition to the 0+_3 excited state in 112Cd (1871.0 keV) has been established. This transition is discussed in the context of a possible enhancement of the decay rate by several orders of magnitude given that the ECEC(0\nu) process is nearly degenerate with an excited state in the daughter nuclide. Prospects for investigating such a process in future experiments are discussed. The beta-beta decay limits for 124Sn to the excited states of 124Te were obtained on the level of (0.8-1.2)\times 10 21 y at the 90% C.L.

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

A. S. Barabash, Ph. Hubert, A. Nachab, S. I. Konovalov, I. A. Vanyushin, et al.. Search for beta+EC and ECEC processes in 112Sn and beta beta decay of 124Sn to the excited states of 124Te. Nuclear Physics A, 2008, 807, pp.269-281. ⟨10.1016/j.nuclphysa.2008.04.009⟩. ⟨in2p3-00395490⟩