New measurement of double-β decays of 100Mo to excited states of 100Ru with the CUPID-Mo experiment

The CUPID-Mo experiment, located at the Laboratoire Souterrain de Modane (France), was a demonstrator experiment for CUPID. It consisted of an array of 20Li2100MoO4 (LMO) calorimeters, each equipped with a Ge light detector for particle identification. In this work, we present the result of a search for two-neutrino and neutrinoless double-β decays of 100Mo to the first 0+ and 2+ excited states of 100Ru using the full CUPID-Mo exposure (2.71kgyr of LMO). We measure the half-life of 2νββ decay to the 0+1 state as T2ν→0+11/2=(7.5±0.8(stat.)+0.4−0.3(syst.))×1020yr. The bolometric technique enables measurement of the electron energies as well as the γ rays from nuclear deexcitation and this all…