Long-range self-interacting dark matter in the Sun

TL;DR

This paper explores how long-range self-interactions of dark matter, mediated by a light scalar, affect its capture and annihilation in the Sun, providing new calculations and constraints based on quantum mechanics and observational data.

Contribution

It introduces a non-perturbative calculation of the self-capture rate for SIDM with a Yukawa potential, bridging the gap between perturbative and classical approaches, and analyzes the impact on solar dark matter detection.

Findings

Self-capture rate can be significantly enhanced by long-range interactions.

Sommerfeld enhancement affects both s- and p-wave annihilation processes.

Constraints on dark matter properties are derived from Super-Kamiokande data and relic density observations.

Abstract

We investigate the implications of the long-rang self-interaction on both the self-capture and the annihilation of the self-interacting dark matter (SIDM) trapped in the Sun. Our discussion is based on a specific SIDM model in which DM particles self-interact via a light scalar mediator, or Yukawa potential, in the context of quantum mechanics. Within this framework, we calculate the self-capture rate across a broad region of parameter space. While the self-capture rate can be obtained separately in the Born regime with perturbative method, and the classical limits with the Rutherford formula, our calculation covers the gap between in a non-perturbative fashion. Besides, the phenomelogy of both the Sommerfeld-enhanced s- and p-wave annihilation of the solar SIDM is also involved in our discussion. Moreover, by combining the analysis of the Super-Kamiokande (SK) data and the observed DM relic density, we constrain the nuclear capture rate of the DM particles in the presence of the dark Yukawa potential. The consequence of the long-range dark force on probing the solar SIDM turns out to be significant if the force-carrier is much lighter than the DM particle, and a quantitative analysis is provided.