Optimizing the energy threshold of light detectors coupled to luminescent bolometers

TL;DR

This paper presents a software algorithm that significantly lowers the energy threshold of bolometric light detectors, enhancing particle discrimination in neutrinoless double beta decay experiments.

Contribution

The work introduces a novel algorithm to improve the sensitivity of bolometric light detectors at cryogenic temperatures, enabling better background discrimination.

Findings

Threshold lowered substantially in tested detectors

Improved discrimination between beta/gamma and alpha interactions

Enhanced sensitivity in low-light emission scenarios

Abstract

Bolometers have proven to be good detectors for the search of neutrinoless double beta decay. By operating at cryogenic temperatures, they feature excellent energy resolution and low background. The detection of the possible light emitted when particles interact in the bolometer is a promising method to lower the background of the experiments. The different amount of light emitted in beta/gamma and alpha interactions, whether due to scintillation or Cerenkov emission, allows to discriminate the two interaction types. Because of the cryogenic environment, light detectors are often bolometers. In this work we present a software algorithm to lower the energy threshold of bolometric light detectors coupled to luminescent bolometers. The application to data from Ge light detectors coupled to ZnMoO4 and TeO2 bolometers shows that the energy threshold can be lowered substantially, increasing the discrimination power when the amount of emitted light is small.