A search for various double beta decay modes of tin isotopes

Abstract

For the first time an extensive search for various double beta decay modes of 124Sn and 112Sn has been performed. A total exposure of 43.29 kg.days has been accumulated. New half-life limits of 124Sn into excited states of 124Te have been obtained; the lower half-life limit for the first excited 2+ state at 602.7keV is T_1/2 > 3.1 *10^{18}yrs (90 % CL) and for the first excited 0+ state T_1/2 > 7.7 *10^{18}yrs (90 % CL). For the very first time, ground state and excited state transitions of 112Sn have been experimentally explored. The obtained half-life limits for ECEC and beta+/EC into the first excited 2+ state of 112Cd are both T_1/2 >1.4 *10^{18}yrs (90 % CL). A resonance enhancement in the decay rate for 0nuECEC might be expected for the 0+-state at 1870.9keV due to degeneracy with the 112Sn ground state. No signal was found resulting in a lower half-life limit of T_1/2 > 1.6 *10^{18} yrs (90 % CL) for this decay. As all the excited state searches are based on gamma-lines, all half-life limits apply for both neutrino and neutrino-less modes. Neutrinoless ground state transitions were searched for in the ECEC and beta+/EC mode and a limit of T_1/2 > 1.5 *10^{18} yrs (90 % CL) was obtained for ECEC decays of 112Sn, whilst the beta+/EC mode results are inconclusive.

19 pages, 11 figures

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Cited by in corpus (13)

• Neutrinoless Double-Beta Decay: a Probe of Physics Beyond the Standard Model
• Shell model predictions for ${}^{124}$Sn double-beta decay
• Search for double beta decay processes in 106Cd with the help of 106CdWO4 crystal scintillator
• Search for ${\beta }^{+}$EC and ECEC processes in ${}^{112}$Sn and ${\beta }^{-}{\beta }^{-}$ decay of ${}^{124}$Sn to the excited states of ${}^{124}$Te
• Neutrinoless Double-Electron Capture
• Double beta decay experiments
• Double beta decay: present status
• First search for double beta decay of platinum by ultra-low background HP Ge gamma spectrometry
• A search for double beta decays of tin isotopes with enhanced sensitivity
• Uncertainties in nuclear transition matrix elements for ${\beta }^{+}{\beta }^{+}$ and $\epsilon {\beta }^{+}$ modes of neutrinoless positron double-$\beta$ decay within PHFB model
• Preliminary study of feasibility of an experiment looking for excited state double beta transitions in tin
• Required sensitivity to search the neutrinoless double beta decay in ${}^{124}Sn$
• Two-neutrino $\beta \beta$ decay to excited states at next-to-leading order