Search of the neutrino-less double beta decay of$^{82}$ Se into the excited states of$^{82}$ Kr with CUPID-0
Résumé
The CUPID-0 experiment searches for double beta decay using cryogenic calorimeters with double (heat and light) read-out. The detector, consisting of 24 ZnSe crystals 95 $\%$ enriched in$^{82}$ Se and two natural ZnSe crystals, started data-taking in 2017 at Laboratori Nazionali del Gran Sasso. We present the search for the neutrino-less double beta decay of$^{82}$ Se into the 0$_1^+$ , 2$_1^+$ and 2$_2^+$ excited states of$^{82}$ Kr with an exposure of 5.74 kg $\cdot $ yr (2.24 $\times $ 10$^{25}$ emitters $\cdot $ yr). We found no evidence of the decays and set the most stringent limits on the widths of these processes: $\varGamma $ ($^{82}$ Se $\rightarrow ^{82}$ Kr$_{0_1^+}$ )8.55 $\times $ 10$^{-24}$ yr$^{-1}$ , $\varGamma $ ($^{82}$ Se $\rightarrow ^{82}$ Kr$_{2_1^+}$ ) $\,{<}\,6.25 \,{\times }\,10^{-24}$ yr$^{-1}$ , $\varGamma $ ($^{82}$ Se $\rightarrow ^{82}$ Kr$_{2_2^+}$ )8.25 $\times $ 10$^{-24}$ yr$^{-1}$ (90 $\%$ credible interval).
Mots clés
S076H0N
Double beta decay
bolometers
scintillation detector
isotope enrichment
calorimeter: cryogenics
double-beta decay: (0neutrino)
excited state: energy
experimental results
Gran Sasso
selenium: semileptonic decay
electron: spectrum
nucleus: many-body problem
energy: transition
scintillation counter: crystal
detector: energy resolution