Speaker
Description
We are commissioning a liquid argon (LAr) cryostat at Queen’s to
study the properties of noble liquids and photo detectors. It will enable
local experimental research on xenon-doped liquid argon, a promising tar-
get medium for next-generation dark matter detectors such as DarkSide-
LowMass and the Scintillating Bubble Chamber (SBC), which aim to
probe weakly interacting massive particles (WIMPs) at sub-GeV mass
scales, and it will allow the characterization of sophisticated silicon pho-
tomultipliers.
In pure liquid argon, scintillation light is emitted at 128 nm with a long-
lived triplet component that enables pulse-shape discrimination. Xenon
doping shifts the emission to 178 nm on much faster timescales, increasing
light yield by up to ∼25% and enabling lower detection thresholds, but
at the cost of reduced pulse-shape discrimination, motivating dedicated
R&D to understand and optimize this trade-off.
The first and essential step toward these studies is the commissioning
of the cryostat and its supporting infrastructure, including the gas han-
dling, purification, and SiPM-based data acquisition systems. Following
commissioning, the facility will support studies of radon mitigation using
zeolite-based adsorption. While activated charcoal is the current industry
standard, recent results indicate that silver-zeolites have superior adsorp-
tion coefficient at ambient temperatures. This facility will investigate
their effectiveness at cryogenic temperatures, compatibility with xenon-
doped argon, and achievable radiopurity. Furthermore a custom designed
double-phase Time Projection Chamber (TPC) will allow for the very
first characterization of ionization signal from xenon-doped argon, as well
as of triethylamine, trimethylamine and trimethylglycine doped argon at
kev and sub-kev scale. In addition, the facility will enable the cryogenic
characterization in both pure and xenon-doped liquid argon of digitally
controlled silicon photomultipliers (3D-dSiPMs) developed at the Univer-
sit´e de Sherbrooke. Overall, this program aims to provide critical R&D
input for noble-liquid dark matter detectors and associated photosensor technologies
aimed at extending sensitivity to sub-GeV mass scales.
| Keyword-1 | Noble-liquid WIMPs detectors |
|---|---|
| Keyword-2 | Digital SiPMs |