Spin dependent dark matter searches in liquid noble detectors

The nature of dark matter is one of the fundamental questions about the universe today, at the forefront of physics research. Direct detection experiments seek to observe interactions of dark matter particles with atomic nuclei. The parameter space of viable DM candidates and their properties is very large, and a diverse range of techniques are being pursued to access a broader ensemble of DM scenarios.

The lowest dark matter masses are accessible using low threshold experiments. The QUEST-DMC project combines a macroscopic quantum system, superfluid helium-3, with state-of-the art quantum technologies to give an ultra low threshold dark matter search. At higher dark matter masses large scale liquid noble time projection chambers lead searches for dark matter interactions down to very low cross sections.

The DarkSide-20k experiment is a 50-tonne liquid argon detector under construction in the LNGS laboratory.

This project will use these complimentary projects to probe spin dependent dark matter interactions across a broad range of dark matter masses. The student will participate in the first dark matter search limit with the QUEST-DMC experiment - contributing to the background measurements, modelling and statistical analysis. They will characterise a sodium iodide detector and carry out measurements of the dominant gamma ray background, a new measurement in ultra-low temperature cryostats in the UK.

They will simulate the propagation of gammas through the detector using Monte Carlo techniques. The determined background spectrum will be a key input to spin dependent low mass dark matter limit setting. They will also be involved in commissioning of the DarkSide experiment and preparation for a complimentary spin dependent dark matter search at higher dark matter masses.

This will be one of the first spin dependent dark matter analyses in argon, utilising the high target mass in DarkSide-20k to allow sensitivity to subdominant interactions.