Resolution enhancement with light/heat decorrelation in CUPID-0 bolometric detector

Abstract

The CUPID-0 experiment searches for neutrinoless double beta decay ($0\nu\beta\beta$) using the first array of enriched Zn$^{82}$Se scintillating bolometers with double (heat and light) read-out. To further enhance the CUPID-0 detector performances, the heat-light correlation has been exploited to improve the energy resolution. Different decorrelation algorithms have been studied and the best result is the average reduction of the full width at half maximum (FWHM) energy resolution to $(90.5\pm0.6)~\%$ of its original value , corresponding to a change from $\text{FWHM}=(20.7\pm0.5)~\text{keV}$ to $\text{FWHM}=(18.7\pm0.5)~\text{keV}$ at the 2615 keV $\gamma$ line.