Direct detection of cosmic ray-boosted puffy dark matter

TL;DR

This paper investigates how the size and mediator effects influence the direct detection limits of cosmic ray-boosted puffy dark matter, finding that these effects lead to stronger constraints than for point-like dark matter.

Contribution

It introduces the consideration of the puffy dark matter radius effect in direct detection analysis, extending previous point-like DM models.

Findings

Limits for puffy DM are stronger than for point-like DM.

Momentum-transfer dependence is affected by both mediator and DM size.

Re-derivation of detection limits for point-like DM for comparison.

Abstract

For the light relativistic dark matter (DM) boosted by high energy cosmic ray, its scattering cross section with the nucleon is sensitively dependent on the momentum-transfer and such an dependence is caused by the mediator in the scattering. For puffy DM particle with a size, the momentum-transfer dependence can also arise from the DM radius effect. All these momentum-transfer dependences should be considered. In this note we study the direct detection limits on the cosmic ray-boosted puffy DM for a simplified model with a light mediator. For comparison, we first re-derive the direct detection limits on the cosmic ray-boosted point-like DM. We display the limits on various planes of parameters and find that the limits for the cosmic ray-boosted puffy DM are stronger than for the point-like DM.