The Continuum Dark Matter Zoo

TL;DR

This paper extends continuum dark matter models to include spin-1/2 and spin-1 particles, analyzing their experimental constraints and viability within certain energy gaps, highlighting unique suppression of direct detection signals.

Contribution

It introduces simple continuum analogs of WIMP-like dark matter particles with detailed phenomenological analysis and explores their experimental constraints and future detection prospects.

Findings

Models are viable for gap scales of 60-200 GeV (spin-1/2) and 35-90 GeV (spin-1).

Strong kinematic suppression reduces direct detection bounds.

Existing constraints mainly from indirect detection and CMB decay limits.

Abstract

We generalize the recently proposed continuum dark matter model to the case where the dark matter consists of a spin-$1/2$ or spin-$1$ gapped continuum. We construct simple continuum analogs of weakly interacting massive particles annihilating through the $Z$ portal. We discuss all existing experimental constraints, with the strongest bounds arising from indirect detection and limits on continuum decays from the cosmic microwave background. Our models are phenomenologically viable for gap scales of $60$-$200$ GeV (spin-$1/2$) and $35$-$90$ GeV (spin-$1$), owing to the strong kinematic suppression of direct detection bounds which is unique to continuum states. We comment on future prospects for detection and suggest directions for further continuum model building.