Open Access Publications from the University of California

## Background model and a measurement of the 2nbb decay rate in 130Te with CUORE-0

• Author(s): Zhu, Xiaoyu
CUORE is a ton-scale cryogenic bolometer experiment designed to search for neutrinoless double beta decay ($0\nu\beta\beta$) in $^{130}$Te. CUORE-0 was a single array experiment consisting of 11 kg of $^{130}$Te and was designed to test the detector construction and analysis techniques for CUORE. CUORE-0 operated from 2013 to 2015 in the Laboratori Nazionali del Gran Sasso in Italy and collected a data sample of 9.8 kg$\cdot$yr of $^{130}$Te.
This dissertation will focus on a method for reconstructing the background spectrum and extracting the two neutrino double beta decay ($2\nu\beta\beta$) signal of $^{130}$Te in CUORE-0. Identifying and reducing the most significant background contributions are keys to improving the sensitivity of future $0\nu\beta\beta$ experiments. The background spectrum of CUORE-0 was fit using the spectra of radioactive contaminants generated by Monte Carlo simulations and the $2\nu\beta\beta$ half-life was measured to be $T^{2\nu}_{1/2} = (8.27^{+1.38}_{-0.99} \text{(stat+syst)})\times10^{20} \text{ yr}$