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RESEARCH PRODUCT

Latest results from CUPID-0

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International audience; CUPID-0 is a pilot experiment in scintillating cryogenic calorimetry for the search of neutrino-less double beta decay. 26 ZnSe crystals were operated continuously in the first project phase (March 2017 - December 2018), demonstrating unprecedented low levels of background in the region of interest at the Q-value of $^{82}\rm{Se}$. From this successful experience comes a demonstration of full alpha to beta/gamma background separation, the most stringent limits on the $^{82}\rm{Se}$ neutrino-less double beta decay, as well as the most precise measurement of the $^{82}$Se half-life. After a detector upgrade, CUPID-0 began its second and last phase (June 2019 - February 2020). We present the latest results on the neutrino-less double beta decay of $^{82}\rm{Se}$ with the full isotope exposure of $8.82~\rm{kg}\times\rm{yr}$. We set a lower bound to the ground state half life $\rm{T}_{1/2}( ^{82}\rm{Se})>4.6\times10^{24}$ yr (90 % C.I.). We review the most recent results from a Bayesian search for spectral distortions to the $^{82}\rm{Se}$ double-beta decay spectrum due to exotic decay modes.