Sensitivity of the CUPID experiment to $0\hat{I}½{\hat{I}}^2{\hat{I}}^2$ decay of ${}^{100}$Mo

Abstract

CUPID is a next-generation bolometric experiment to search for neutrinoless double-beta decay ($0\hat{I}½{\hat{I}}^2{\hat{I}}^2$) of ${}^{100}$Mo using Li${}_2$MoO${}_4$ scintillating crystals. It will operate 1596 crystals at $\sim$10 mK in the CUORE cryostat at the Laboratori Nazionali del Gran Sasso in Italy. Each crystal will be facing two Ge-based bolometric light detectors for $\hat{I}\pm$ rejection. We compute the discovery and the exclusion sensitivity of CUPID to $0\hat{I}½{\hat{I}}^2{\hat{I}}^2$ in a Frequentist and a Bayesian framework. This computation is done numerically based on pseudo-experiments. For the CUPID baseline scenario, with a background and an energy resolution of $1.0\times 10^{-4}$ counts/keV/kg/yr and 5 keV FWHM at the Q-value, respectively, this results in a Bayesian exclusion sensitivity (90% c.i.) of ${\hat{T}}_{1/2}>1.6\times 10^{27}\mathrm{yr}$, corresponding to the effective Majorana neutrino mass of ${\hat{m}}_{{\hat{I}}^2{\hat{I}}^2}<9.6$ -- $28\mathrm{meV}$. The Frequentist discovery sensitivity (3$\ddot{I}ƒ$) is ${\hat{T}}_{1/2}=1.0\times 10^{27}\mathrm{yr}$, corresponding to ${\hat{m}}_{{\hat{I}}^2{\hat{I}}^2}=12$ -- $36\mathrm{meV}$.

Accepted for publication in European Physical Journal C