Dark Matter Direct Detection on the Moon

TL;DR

This paper explores the potential of lunar-based dark matter detectors, highlighting that the Moon's lack of atmosphere results in reduced neutrino backgrounds, which could enhance dark matter detection sensitivity.

Contribution

It provides the first estimate of lunar neutrino flux and demonstrates that lunar detectors could outperform Earth-based ones in dark matter searches due to lower neutrino backgrounds.

Findings

Lunar neutrino flux is significantly different from Earth's.

Lunar detectors could have higher sensitivity to dark matter.

Reduced neutrino background improves detection prospects.

Abstract

Direct searches for dark matter with large-scale noble liquid detectors have become sensitive enough to detect the coherent scattering of local neutrinos. This will become a very challenging background to dark matter discovery in planned future detectors. For dark matter with mass above 10 GeV, the dominant neutrino backgrounds on the Earth are atmospheric neutrinos created by cosmic ray collisions with the atmosphere. In contrast, the Moon has almost no atmosphere and nearly all cosmic rays incident on the Moon first collide with the lunar surface, producing a very different neutrino spectrum. In this work we estimate the total flux and spectrum of neutrinos near the surface of the Moon. We then use this to show that a large-scale liquid xenon or argon detector located on the Moon could potentially have significantly greater sensitivity to dark matter compared to an equivalent detector on the Earth due to effectively reduced neutrino backgrounds.