Applications of Low Temperature Bolometers to Reactor Neutrinos and Neutrinoless Double Beta Decay

Abstract

Low temperature bolometers are a powerful tool for precise energy measurements. This thesis describes the application of bolometers to the detection of Coherent Elastic Neutrino-Nucleus Scattering (CEvNS) and Neutrinoless Double Beta Decay (0νββ).

First, design, development, and feasibility studies of the Ricochet CEvNS experiment are presented. In addition, results are shown demonstrating that upcoming CEvNS experiments are a powerful tool to search for new physics, including a neutrino magnetic moment and non-standard interactions between neutrinos and quarks. In particular, combining multiple detector materials and measuring CEvNS at a reactor places leading bounds on beyond the Standard Model neutrino-nucleon interactions. Limiting such interactions is crucial for upcoming beam experiments such as DUNE. In addition, results are presented showing the capability of next generation experiments to measure low energy neutrinos for the first time.

Next, design, development, and analysis of the CUPID and CUPID-Mo experiments are presented. Characterization of bolometric crystals grown by a US-based crystal provider is shown, demonstrating progress towards the CUPID design goal. Next, improvements to the CUPID-Mo analysis are presented, including cuts and time corrections, followed by an initial 0νββ measurement with a simplified background model. Finally, a CUPID-Mo background model is described culminating in characterization of backgrounds required for a future precise 0νββ measurement, and a preliminary measurement of 2νββ in molybdenum. These CUPID-Mo results demonstrate the feasibility of the next-generation CUPID experiment.