- Collaboration, CUORE;
- Adams, DQ;
- Alduino, C;
- Alfonso, K;
- III, FT Avignone;
- Azzolini, O;
- Bari, G;
- Bellini, F;
- Benato, G;
- Branca, M Biassoni A;
- Brofferio, C;
- Bucci, C;
- Camilleri, J;
- Caminata, A;
- Campani, A;
- Canonica, L;
- Cao, XG;
- Capelli, S;
- Cappelli, L;
- Cardani, L;
- Casali, P Carniti N;
- Celi, E;
- Copello, D Chiesa M Clemenza S;
- Cosmelli, C;
- Cremonesi, O;
- Creswick, RJ;
- D'Addabbo, A;
- Dafinei, I;
- Davis, CJ;
- Domizio, S Dell'Oro S Di;
- Dompè, V;
- Fang, DQ;
- Fantini, G;
- Ferri, M Faverzani E;
- Ferroni, F;
- Fiorini, E;
- Franceschi, MA;
- Freedman, SJ;
- Fu, SH;
- Fujikawa, BK;
- Giachero, A;
- Gironi, L;
- Giuliani, A;
- Gorla, P;
- Gotti, C;
- Gutierrez, TD;
- Han, K;
- Heeger, KM;
- Huang, RG;
- Huang, HZ;
- Johnston, J;
- Keppel, G;
- Kolomensky, Yu G;
- Ligi, C;
- Ma, L;
- Ma, YG;
- Marini, L;
- Maruyama, RH;
- Mayer, D;
- Mei, Y;
- Moggi, N;
- Morganti, S;
- Napolitano, T;
- Nastasi, M;
- Nikkel, J;
- Nones, C;
- Norman, EB;
- Nucciotti, A;
- Nutini, I;
- O'Donnell, T;
- Ouellet, JL;
- Pagan, S;
- Pagliarone, CE;
- Pagnanini, L;
- Pallavicini, M;
- Pattavina, L;
- Pavan, M;
- Pessina, G;
- Pettinacci, V;
- Pira, C;
- Pirro, S;
- Pozzi, S;
- Previtali, E;
- Puiu, A;
- Rosenfeld, C;
- Rusconi, C;
- Sakai, M;
- Sangiorgio, S;
- Schmidt, B;
- Scielzo, ND;
- Sharma, V;
- Singh, V;
- Sisti, M;
- Speller, D;
- Surukuchi, PT;
- Taffarello, L;
- Terranova, F;
- Tomei, C;
- Vetter, KJ;
- Vignati, M;
- Wagaarachchi, SL;
- Wang, BS;
- Welliver, B;
- Wilson, J;
- Wilson, K;
- Winslow, LA;
- Zimmermann, S;
- Zucchelli, S
The CUORE experiment is a large bolometric array searching for the lepton
number violating neutrino-less double beta decay ($0
u\beta\beta$) in the
isotope $\mathrm{^{130}Te}$. In this work we present the latest results on two
searches for the double beta decay (DBD) of $\mathrm{^{130}Te}$ to the first
$0^{+}_2$ excited state of $\mathrm{^{130}Xe}$: the $0
u\beta\beta$ decay and
the Standard Model-allowed two-neutrinos double beta decay ($2
u\beta\beta$).
Both searches are based on a 372.5 kg$\times$yr TeO$_2$ exposure. The
de-excitation gamma rays emitted by the excited Xe nucleus in the final state
yield a unique signature, which can be searched for with low background by
studying coincident events in two or more bolometers. The closely packed
arrangement of the CUORE crystals constitutes a significant advantage in this
regard. The median limit setting sensitivities at 90\% Credible Interval (C.I.)
of the given searches were estimated as $\mathrm{S^{0
u}_{1/2} = 5.6 \times
10^{24} \: \mathrm{yr}}$ for the ${0
u\beta\beta}$ decay and
$\mathrm{S^{2
u}_{1/2} = 2.1 \times 10^{24} \: \mathrm{yr}}$ for the
${2
u\beta\beta}$ decay. No significant evidence for either of the decay modes
was observed and a Bayesian lower bound at $90\%$ C.I. on the decay half lives
is obtained as: $\mathrm{(T_{1/2})^{0
u}_{0^+_2} > 5.9 \times 10^{24} \:
\mathrm{yr}}$ for the $0
u\beta\beta$ mode and
$\mathrm{(T_{1/2})^{2
u}_{0^+_2} > 1.3 \times 10^{24} \: \mathrm{yr}}$ for the
$2
u\beta\beta$ mode. These represent the most stringent limits on the DBD of
$^{130}$Te to excited states and improve by a factor $\sim5$ the previous
results on this process.