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arXiv · 0804.1198

A search for double beta decays of tin isotopes with enhanced sensitivity

Abstract

A search for the various double beta decay modes of 124Sn and 112Sn has been performed on 75 kg.days of data. New half-life limits for excited states in 124Sn have been obtained including a lower limit for the decay into the first excited 2+ state of 124Te of T_half > 0.87e20 yrs (90% CL) and into the first excited 0+ state of T_half > 1.08e20 yrs (90% CL). Ground state and excited state transitions of 112Sn have also been experimentally explored. A limit for the 2 neutrino double electron capture of T_half > 1.8e19 yrs (90% CL) is obtained. The non-observation of de-excitation gammas from the 0+ at 1888.5keV results in a lower half-life limit on the 0 neutrino double electron capture decay of 112Sn of T_half > 0.8e19 yrs (90% CL), despite a possible resonant enhancement of the decay rate due to degenerated states.

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J. Dawson, D. Degering, M. Köhler, R. Ramaswamy, C. Reeve, J. R. Wilson, K. Zuber. 2008-07-29. A search for double beta decays of tin isotopes with enhanced sensitivity. https://doi.org/10.1103/physrevc.78.035503

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