Speaker
Description
The AMoRE-II searches for neutrinoless double-beta decay of 100Mo using molybdate-based crystal detectors that simultaneously measure heat and scintillation signals at millikelvin temperatures. The experiment is located at the Yemilab underground laboratory in South Korea. Achieving the required ultra-low-background environment with a 10 mK sample space necessitated the development of a custom large-scale dilution refrigerator featuring a 1-m-diameter mixing-chamber plate.
A 3-tonne PbCu low-temperature radiation shield has been installed below the mixing-chamber plate. The shield is suspended by individual supports consisting of stainless-steel rods and Kevlar strings, combined with soft thermal links to minimize vibration transfer while maintaining adequate thermalization.
In this presentation, we discuss the design and performance of the AMoRE-II cryostat, including mechanical support structures and vibration-mitigation considerations. We also report the refrigerator performance after installation of the experimental wiring configuration and the low-temperature shield.