# DELight: a Direct search Experiment for Light dark matter with superfluid helium

### Submission summary

 As Contributors: Belina von Krosigk Arxiv Link: https://arxiv.org/abs/2209.10950v1 (pdf) Date submitted: 2022-09-23 10:03 Submitted by: von Krosigk, Belina Submitted to: SciPost Physics Proceedings Proceedings issue: 14th International Conference on Identification of Dark Matter Academic field: Physics Specialties: Gravitation, Cosmology and Astroparticle Physics High-Energy Physics - Experiment Approach: Experimental

### Abstract

To reach ultra-low detection thresholds necessary to probe unprecedentedly low Dark Matter masses, target material alternatives and novel detector designs are essential. One such target material is superfluid $^4$He which has the potential to probe so far uncharted light Dark Matter parameter space at sub-GeV masses. The new "Direct search Experiment for Light dark matter", DELight, will be using superfluid helium as active target, instrumented with magnetic micro-calorimeters. It is being designed to reach sensitivity to masses well below 100 MeV in Dark Matter-nucleus scattering interactions.

###### Current status:
Editor-in-charge assigned

### Submission & Refereeing History

Submission 2209.10950v1 on 23 September 2022

## Reports on this Submission

### Report

In this proceeding authors raising a very important issue - how to reach a super-low threshold to probe ultra low Dark Matter masses. They suggest to use superfluid 4He as a target material in a new experiment called DELight. The proceeding describes how the goal (sensitivity to masses well below 100MeV) can be reached. One can find detailed description of detector concept and calculated projections on spin-independent DM-nucleon scattering limits.
The manuscript is clearly written and well organised.
It is also suitably formatted for publication.
I recommend the manuscript for publication in its present form and wish author success with DELight.

• validity: high
• significance: top
• originality: high
• clarity: high
• formatting: perfect
• grammar: excellent