First test of an enriched $^{116}$CdWO$_4$ scintillating bolometer for neutrinoless double-beta-decay searches

TL;DR

This paper reports the successful testing of an enriched $^{116}$CdWO$_4$ scintillating bolometer, demonstrating high energy resolution, particle identification, and radiopurity, indicating its potential for neutrinoless double-beta decay searches.

Contribution

First successful test of an enriched $^{116}$CdWO$_4$ scintillating bolometer, showing promising performance for neutrinoless double-beta decay experiments.

Findings

High energy resolution (2-7 keV FWHM) achieved

Effective particle identification demonstrated

High internal radiopurity confirmed

Abstract

For the first time, a cadmium tungstate crystal scintillator enriched in $^{116}$Cd has been succesfully tested as a scintillating bolometer. The measurement was performed above ground at a temperature of 18 mK. The crystal mass was 34.5 g and the enrichment level ~82 %. Despite a substantial pile-up effect due to above-ground operation, the detector demonstrated a high energy resolution (2-7 keV FWHM in 0.2-2.6 MeV $\gamma$ energy range), a powerful particle identification capability and a high level of internal radiopurity. These results prove that cadmium tungstate is an extremely promising detector material for a next-generation neutrinoless double-beta decay bolometric experiment, like that proposed in the CUPID project (CUORE Upgrade with Particle IDentification).