Half-Life and Precision Shape Measurement of the 2νββ Decay of Te130

Pagliarone, C.; Adams, D.  q.; Alduino, C.; Alfonso, K.; Armatol, A.; Avignone, F.  t.; Azzolini, O.; Bari, G.; Bellini, F.; Benato, G.; Beretta, M.; Biassoni, M.; Branca, A.; Brofferio, C.; Bucci, C.; Camilleri, J.; Caminata, A.; Campani, A.; Cao, J.; Capelli, C.; Capelli, S.; Cappelli, L.; Cardani, L.; Carniti, P.; Casali, N.; Celi, E.; Chiesa, D.; Clemenza, M.; Copello, S.; Cremonesi, O.; Creswick, R.  j.; D'Addabbo, A.; Dafinei, I.; Dell'Oro, S.; Di Domizio, S.; Di Lorenzo, S.; Dixon, T.; Fang, D.  q.; Faverzani, M.; Ferri, E.; Ferroni, F.; Fiorini, E.; Franceschi, M.  a.; Freedman, S.  j.; S.  h., Fu; Fujikawa, B.  k.; Ghislandi, S.; Giachero, A.; Girola, M.; Gironi, L.; Giuliani, A.; Gorla, P.; Gotti, C.; Guillaumon, P.  v.; Gutierrez, T.  d.; Han, K.; Hansen, E.  v.; Heeger, K.  m.; Helis, D.  l.; Huang, H.  z.; Hurst, M.  t.; Keppel, G.; Kolomensky, Yu.  g.; Kowalski, R.; Liu, R.; Ma, L.; Y.  g., Ma; Marini, L.; Maruyama, R.  h.; Mayer, D.; Mei, Y.; Moore, M.  n.; Napolitano, T.; Nastasi, M.; Nones, C.; Norman, E.  b.; Nucciotti, A.; Nutini, I.; O'Donnell, T.; Olmi, M.; Oregui, B.  t.; Pagan, S.; Pagnanini, L.; Pallavicini, M.; Pattavina, L.; Pavan, M.; Pessina, G.; Pettinacci, V.; Pira, C.; Pirro, S.; Pottebaum, E.  g.; Pozzi, S.; Previtali, E.; Puiu, A.; Quitadamo, S.; Ressa, A.; Rosenfeld, C.; Schmidt, B.; Serino, R.; Shaikina, A.; Sharma, V.; Singh, V.; Sisti, M.; Speller, D.; Surukuchi, P.  t.; Taffarello, L.; Tomei, C.; Torres, A.; Torres, J.  a.; Vetter, K.  j.; Vignati, M.; Wagaarachchi, S.  l.; Welliver, B.; Wilson, J.; Wilson, K.; Winslow, L.  a.; Xie, F.; Zhu, T.; Zimmermann, S.; Zucchelli, S.; Castillo, D.; Kotila, J.; Menéndez, J.; Niţescu, O.; Šimkovic, F.; Null, Null

doi:10.1103/jdhf-hn4l

We present a new measurement of the 2νββ half-life of Te130 (T1/22ν) using the first complete model of the CUORE data, based on 1038 kg yr of collected exposure. Thanks to optimized data selection, we achieve a factor of two improvement in precision, obtaining T1/22ν=(9.32 -0.04+0.05stat -0.07+0.07syst)×1020 yr. The signal-to-background ratio is increased by 70% compared to our previous results, enabling the first application of the improved 2νββ formalism to Te130. Within this framework, we determine a credibility interval for the effective axial coupling in the nuclear medium as a function of nuclear matrix elements. We also extract values for the higher-order nuclear matrix element ratios: second-to-first and third-to-first. The second-to-first ratio agrees with nuclear model predictions, while the third-to-first ratio deviates from theoretical expectations. These findings provide essential tests of nuclear models and key inputs for future 0νββ searches.