Performances of a large mass ZnMoO4 scintillating bolometer for a next generation neutrinoless double beta decay experiment

TL;DR

This paper evaluates a 330 g ZnMoO4 scintillating bolometer's performance, demonstrating its potential for next-generation neutrinoless double beta decay experiments through excellent energy resolution and effective background discrimination.

Contribution

It provides detailed performance metrics of a large ZnMoO4 bolometer, highlighting its suitability for future neutrinoless double beta decay searches with improved resolution and background rejection.

Findings

Energy resolution of 6.3 keV at 2615 keV

Low internal radioactive contamination levels

Effective alpha vs beta/gamma discrimination

Abstract

We present the performances of a 330 g zinc molybdate (ZnMoO4) crystal working as scintillating bolometer as a possible candidate for a next generation experiment to search for neutrinoless double beta decay of 100Mo. The energy resolution, evaluated at the 2615 keV gamma-line of 208Tl, is 6.3 keV FWHM. The internal radioactive contaminations of the ZnMoO4 were evaluated as <6 microBq/kg (228Th) and 27\pm6 microBq/kg (226Ra). We also present the results of the alpha vs beta/gamma discrimination, obtained through the scintillation light as well as through the study of the shape of the thermal signal alone.