Pushing noble liquids to new limits: dark matter detection technology in LXe and superfluid 4He

by Scott Hertel (MIT)

Wednesday 20 May 2015, 10:00 → 11:00 US/Pacific

Kavli Auditorium (SLAC)

Dark matter represents known particles beyond the standard model; our job is now to create detectors that can measure these particles' properties and then fit them into a new more inclusive and fundamental model for particle physics. The benefits of noble liquids as a dark matter target material for these searches include high radio-purity, high background rejection, and `easy' scalability to large (ton-scale) masses. I will give an overview of two LXe-based efforts, LUX and its successor LZ, emphasizing personal efforts to improve calibration sources dissolved within the LXe itself. At the other end of noble-element mass scale, I will discuss a complementary strategy for probing light dark matter using superfluid 4He as the target mass. The superfluid nature enables several unique excitations within the medium, and the mK-scale temperature enables readout of those excitations using ultra-sensitive calorimetry. A recent laboratory demonstration of some of these principles will be shown.