Speaker
Description
Dark matter direct detection experiments have historically focused on searches for GeV-TeV/c$^2$ mass WIMP dark matter, undergoing spin-independent scattering interactions with a target. However, there are well motivated models at lower masses including those with spin-dependent interactions. This parameter space remains significantly less constrained due to the challenge of achieving lower energy thresholds and the limited number of target nuclei with non-zero nuclear spin for spin-dependent interactions.
The QUEST-DMC experiment addresses these challenges using a gram scale superfluid helium-3 bolometer, with $10^{-7}$ eV superfluid gap, instrumented with nanowire resonators. Low noise quantum sensor readout enables low threshold detection, probing new parameter space. Recent work on development of this readout scheme to optimise energy threshold will be presented, along with first data and comparison to simulations.
A subsequent experimental run is now underway, reaching new lowest temperatures of 130 $\mu K$. Initial measurements and energy calibration techniques will be shown, with developments underway to establish complementary measurements of the energy scale. The dark matter search has potential to reach unprobed parameter space and further plans to extend the reach of this globally unique experiment will be discussed.