Snowmass 2021 Underground Facilities for the Cosmic Frontier Topical Report

TL;DR

This report discusses the future underground facilities needed for next-generation dark matter detection experiments, focusing on larger detectors, new technologies for low-mass dark matter, and capabilities for studying time-dependent signals.

Contribution

It provides a comprehensive overview of the infrastructure requirements for advanced underground dark matter experiments using various detection technologies.

Findings

Next-generation detectors will require larger target masses and lower thresholds.

Facilities must support directional detection and long-term exposure experiments.

Technologies for low-mass dark matter detection are being developed for underground use.

Abstract

Detecting dark matter directly using sensitive underground detectors is one of the most promising ways to address the question of what is dark matter. The next generation underground experiments will search for dark matter in two directions. One is to use larger target mass detectors to further probe smaller cross sections in the WIMP parameter space and the other is to probe lower mass dark matter which requires new technologies with extremely low threshold. Once dark matter is detected, experiments with directional sensitivities and experiments with longer exposure and larger target masses are needed for the time-dependent signatures, such as annual modulations, to verify their cosmic origin and to further study their properties. This report covers the underground facilities need for the next generation dark matter search experiments with noble liquids, cryogenic bolometers and other technologies.