Development of MMC-based lithium molybdate cryogenic calorimeters for AMoRE-II

A Agrawal, VV Alenkov, P Aryal, H Bae, J Beyer… - arXiv preprint arXiv …, 2024 - arxiv.org
A Agrawal, VV Alenkov, P Aryal, H Bae, J Beyer, B Bhandari, RS Boiko, K Boonin
arXiv preprint arXiv:2407.12227, 2024arxiv.org
The AMoRE collaboration searches for neutrinoless double beta decay of $^{100} $ Mo
using molybdate scintillating crystals via low temperature thermal calorimetric detection. The
early phases of the experiment, AMoRE-pilot and AMoRE-I, have demonstrated competitive
discovery potential. Presently, the AMoRE-II experiment, featuring a large detector array with
about 90 kg of $^{100} $ Mo isotope, is under construction. This paper discusses the
baseline design and characterization of the lithium molybdate cryogenic calorimeters to be …
The AMoRE collaboration searches for neutrinoless double beta decay of Mo using molybdate scintillating crystals via low temperature thermal calorimetric detection. The early phases of the experiment, AMoRE-pilot and AMoRE-I, have demonstrated competitive discovery potential. Presently, the AMoRE-II experiment, featuring a large detector array with about 90 kg of Mo isotope, is under construction.This paper discusses the baseline design and characterization of the lithium molybdate cryogenic calorimeters to be used in the AMoRE-II detector modules. The results from prototype setups that incorporate new housing structures and two different crystal masses (316 g and 517 - 521 g), operated at 10 mK temperature, show energy resolutions (FWHM) of 7.55 - 8.82 keV at the 2.615 MeV Tl line, and effective light detection of 0.79 - 0.96 keV/MeV. The simultaneous heat and light detection enables clear separation of alpha particles with a discrimination power of 12.37 - 19.50 at the energy region around Li(n, )H with Q-value = 4.785 MeV. Promising detector performances were demonstrated at temperatures as high as 30 mK, which relaxes the temperature constraints for operating the large AMoRE-II array.
arxiv.org