Speaker
Description
The TINY (Two Isotopes for Neutrinoless double beta decaY search) project aims to develop bolometric detectors incorporating Zr-96 and Nd-150 isotopes for neutrinoless double beta decay (0νββ) searches. These isotopes possess some of the highest Qββ values among candidate nuclei, positioning the region of interest above most natural gamma and beta backgrounds. Additionally, the large phase-space factor enhances sensitivity to the effective Majorana neutrino mass.
With the advantage of “source=detector” technology, a 20 g Cs₂ZrCl₆ (CZC) scintillating crystal was measured for the first time as a bolometer. The study presents the first experimental results from a CZC crystal operated as a cryogenic calorimeter with simultaneous heat and light readout, using NTDs (Neutron transmutation doped) thermistors. The crystal was operated at ~15 mK temperature in a dedicated facility at CEA (Saclay). First tests demonstrate a promising performance in terms of sensitivity and energy resolution. Moreover, thanks to the high scintillation yield, the dual readout provides efficient discrimination between β/γ interactions and α events.
These findings confirm the possibility of building a bolometric Zr-based 0n2b experiment. TINY experiment will work on R&D towards reproducible ~100g scale detectors with high performance and radiopurity. Sensitivity evaluation for small-scale underground experiment demonstrates the potential of this technology for future 0n2b studies, as well as possibility of presice measurement of 2n2b spectrum and investigation of single beta decay of Zr-96 which was not yet observed.