학술논문

Optimization of the first CUPID detector module
Document Type
article
Source
Subject
physics.ins-det
nucl-ex
Language
Abstract
CUPID will be a next generation experiment searching for the neutrinolessdouble $\beta$ decay, whose discovery would establish the Majorana nature ofthe neutrino. Based on the experience achieved with the CUORE experiment,presently taking data at LNGS, CUPID aims to reach a background freeenvironment by means of scintillating Li$_{2}$$^{100}$MoO$_4$ crystals coupledto light detectors. Indeed, the simultaneous heat and light detection allows usto reject the dominant background of $\alpha$ particles, as proven by theCUPID-0 and CUPID-Mo demonstrators. In this work we present the results of thefirst test of the CUPID baseline module. In particular, we propose a newoptimized detector structure and light sensors design to enhance theengineering and the light collection, respectively. We characterized the heatdetectors, achieving an energy resolution of (5.9 $\pm$ 0.2) keV FWHM at the$Q$-value of $^{100}$Mo (about 3034 keV). We studied the light collection ofthe baseline CUPID design with respect to an alternative configuration whichfeatures gravity-assisted light detectors' mounting. In both cases we obtainedan improvement in the light collection with respect to past measures and wevalidated the particle identification capability of the detector, which ensuresan $\alpha$ particle rejection higher than 99.9%, fully satisfying therequirements for CUPID.