Speaker
Description
This poster presents the demonstrated and potential physics capabilities for liquid argon light collection detectors able to resolve both scintillation and Cherenkov signals. This work builds on the first event-by-event observation of Cherenkov radiation from sub-MeV electrons in a high-yield scintillator (liquid argon) detector (PRL 135 (2025) 17, 171804, PRD 112 (2025) 7, 072010), representing a milestone in low-energy particle detector development and one of the major goals of 2021 Snowmass Process. These results utilize the Coherent CAPTAIN-Mills (CCM) experiment, a 10-ton liquid argon light collection detector located at the Los Alamos National Laboratory pion decay-at-rest source. The detector is instrumented with 200 8-inch PMTs, 80% of which are coated in a wavelength shifter and 20% are uncoated. Using gamma-rays from a sodium-22 radioactive source, we have isolated prompt Cherenkov light with >5 sigma confidence, made possible by the unique combination of coated and uncoated PMTs. This poster additionally presents an axion-like-particle study from the CCM experiment, demonstrating the physics potentials of hybrid liquid argon light collection detectors, and discuss future capabilities of ultra-large liquid argon light collection detectors.