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تسجيل مستخدم جديدRejection of randomly coinciding events in Li$_2$$^{100}$MoO$_4$ scintillating bolometers using light detectors based on the Neganov-Luke effect
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Random coincidences of nuclear events can be one of the main background sources in low-temperature calorimetric experiments looking for neutrinoless double-beta decay, especially in those searches based on scintillating bolometers embedding the promising double-beta candidate $^{100}$Mo, because of the relatively short half-life of the two-neutrino double-beta decay of this nucleus. We show in this work that randomly coinciding events of the two-neutrino double decay of $^{100}$Mo in enriched Li$_2$$^{100}$MoO$_4$ detectors can be effectively discriminated by pulse-shape analysis in the light channel if the scintillating bolometer is provided with a Neganov-Luke light detector, which can improve the signal-to-noise ratio by a large factor, assumed here at the level of $sim 750$ on the basis of preliminary experimental results obtained with these devices. The achieved pile-up rejection efficiency results in a very low contribution, of the order of $sim 6times10^{-5}$ counts/(keV$cdot$kg$cdot$y), to the background counting rate in the region of interest for a large volume ($sim 90$ cm$^3$) Li$_2$$^{100}$MoO$_4$ detector. This background level is very encouraging in view of a possible use of the Li$_2$$^{100}$MoO$_4$ solution for a bolometric tonne-scale next-generation experiment as that proposed in the CUPID project.
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