Center for Underground Physics

Meeting ID: 882 8271 0155

Password: 723373

 

The nature of dark matter remains one of the mysteries in modern physics. While traditional searches have focused on the weak-scale mass range, a growing body of theoretical and experimental work is now exploring the possibility of low-mass dark matter, with mass spanning from MeV down to sub-eV scales. This shift in focus has sparked a wave of technological innovation and a generation of new experiments aimed at detecting feeble interactions between light dark matter and ordinary matter. To address this new direction, a new experimental setup for low-mass dark matter searches is currently being commissioned at the Kamioka Underground Laboratory. A dilution refrigerator has been installed underground, and gamma and neutron shielding is under construction. Ambient gamma and neutron levels have been measured and a Geant4 simulation model has been constructed to predict experimental background rates with this setup. Multiple experiments are under preparation for g-yr level dark matter searches starting in late 2025, including superconducting targets with optical TES sensor readout and a test underground run of a superfluid helium payload.