Cosmogenic muons are a major background source in rare event search experiments. To mitigate this background, neutrinoless double beta decay ($0\nu\beta\beta$) and direct detection dark matter experiments prefer to operate in deep underground laboratories, where they can receive adequate shielding from cosmic rays. However, high energy muons can still reach underground and create backgrounds...
Gaseous xenon time projection chambers (GXeTPC) are an excellent detector technology for reducing radiogenic backgrounds in $0\nu\beta\beta$ decay searches due to the extended beta tracks. The signal consists of two emitted beta electrons with 2.45 MeV of energy, and their track lengths scale inversely with the gas pressure, reaching ~2 m in size for 1 bar of gas pressure or ~20 cm at 10 bar....
Target mass is a key consideration in optimizing the design of a future neutrinoless double beta decay detector with xenon. This short talk makes the case that in the current context, to achieve our scientific goals, a target mass larger than 5 tonnes needs to be considered seriously.
To reach the Normal Hierarchy and thus definitively address the question of lepton number conservation, current background levels must be reduced by a factor of ~1000 and some of this must come from improved energy resolution. I suggest this might be achieved in liquid xenon by a series of fundamental changes in design to include (a) the use of low IP additives such as TEA to allow much higher...
