Towards A Direct Detection of the Spin of Dark Matter

TL;DR

This paper explores how higher spin particles as dark matter candidates can be detected and distinguished using directional direct detection experiments, focusing on spin-dependent scattering signatures and recoil energy patterns.

Contribution

It introduces a method to identify the spin of dark matter particles through angular and energy dependence in scattering signals, including a novel supersymmetric higher spin dark sector model.

Findings

Angular dependence distinguishes integer vs. half-integer spins.

Recoil energy patterns determine the spin magnitude.

A characteristic 'SUSY Rilles' signal is proposed for supersymmetric higher spin dark matter.

Abstract

We investigate the contribution of higher spin particles in the signal of direct detection experiments searching for dark matter. We consider a bosonic or fermionic higher spin dark matter (HSDM) candidate which interacts with the Standard Model via a dark U(1) mediator. For a particular subclass of interactions, spin-polarized targets may be used for spin determination: The angular dependence of scatterings can distinguish integer (spin-$s$) vs. half-integer (spin-$s + 1/2$), while the recoil energy dependence of the signal determines $s$. We consider also the signal of a supersymmetric higher spin dark sector, which suggests a characteristic signal (''SUSY Rilles'') for directional direct detection.