Extracting Dark-Matter Mass from Angular Scanning

TL;DR

This paper introduces a new method to estimate dark matter mass using directional detection data, leveraging angular flux curvature, demonstrated with a graphene-based detector model.

Contribution

The paper presents a novel approach to determine dark matter mass from angular spectra in directional detectors, validated with numerical simulations.

Findings

Angular dependence of event rates encodes dark matter mass information.

Curvature of the angular spectrum is a key observable for mass determination.

Numerical analysis confirms the theoretical predictions with a graphene-based detector model.

Abstract

We propose a novel method to determine the mass scale of ambient dark matter, applicable to (at least effectively) two-dimensional direct detection experiments that allow for directionality observables. Due to the motion of the solar system and Earth relative to the Galactic Center and the Sun, the dark-matter flux exhibits a directional preference. We first demonstrate that dark-matter event rates depend non-trivially on the angle between the detection plane and the overall dark-matter flow, with the curvature of this angular spectrum encoding mass information. As proof of principle, we take the recently proposed Graphene-Josephson-Junction-based superlight dark-matter detector as a concrete example and validate these theoretical expectations through numerical analyses.