Velocity Dependence from Resonant Self-Interacting Dark Matter

TL;DR

This paper demonstrates that resonant self-interacting dark matter can naturally produce velocity-dependent cross sections without requiring a light mediator, aligning with astrophysical observations across different scales.

Contribution

It introduces a model-independent explanation for velocity-dependent dark matter interactions via resonance, challenging the common assumption of light mediators.

Findings

Resonant self-interactions can explain velocity dependence in dark matter cross sections.

Explicit models of RSIDM are constructed and analyzed.

Astrophysical constraints on RSIDM are discussed.

Abstract

The dark matter density distribution in small-scale astrophysical objects may indicate that dark matter is self-interacting, while observations from clusters of galaxies suggest that the corresponding cross section depends on the velocity. Using a model-independent approach, we show that resonant self-interacting dark matter (RSIDM) can naturally explain such a behavior. In contrast to what is often assumed, this does not require a light mediator. We present explicit realizations of this mechanism and discuss the corresponding astrophysical constraints.