Search for neutrinoless β+EC decay of Te120 with CUORE-0

We have performed a search for neutrinoless β+EC decay of Te120 using the final CUORE-0 data release. We describe a new analysis method for the simultaneous fit of signatures with different event topology, and of data subsets with different signal efficiency, obtaining a limit on the half-life of the decay of T1/2>1.6×1021 yr at 90% credibility interval (CI). Combining this with results from Cuoricino, a predecessor experiment, we obtain the strongest limit to date, corresponding to T1/2>2.7×1021 yr at 90% CI.