Spin-Dependent Scattering of Scalar and Vector Dark Matter and an Electron

TL;DR

This paper investigates spin-dependent scattering effects of scalar and vector dark matter on electrons, deriving constraints from experiments and highlighting the potential for SD interactions to surpass SI interactions in strength.

Contribution

It provides a comprehensive analysis of spin-dependent dark matter-electron scattering for scalar and vector candidates, including form factors and experimental limits.

Findings

SD scattering can be three orders of magnitude stronger than SI scattering

Derived exclusion limits on SD cross sections from XENON experiments

Identified the significance of p-wave scattering in SD interactions

Abstract

The property of dark matter is unknown so far. However, a model-independent classification of dark matter candidates can be achieved by using various symmetries, as done in the Standard Model. Fermionic dark matter has been researched extremely, one favored candidate is the neutralino in the Minimal Supersymmetric Standard Model, which are required by fermion-boson symmetry and preservation of R-parity. Bosonic dark matter has not been studied sufficiently, especially the scenario of dark matter with mass of sub-GeV. In this paper, we consider the effect of spin-dependent (SD) on scalar and vector dark matter, which are mediated by pseudo-scalar and axial-vector, and evaluate effect on the dark matter-electron scattering cross section. We list all the interaction and form factor of dark matter-electron SD scattering, and use XENON10/100/1T experiment data to derive the exclude limit of SD cross section. We find that the SD scattering of scalar and vector dark matter can be three orders of magnitude stronger than spin-independent (SI) scattering, due to the $p$-wave scattering.