Breit-Wigner Enhancement of Dark Matter Annihilation

TL;DR

This paper proposes that dark matter annihilation rates in the galactic halo can be significantly enhanced by a Breit-Wigner resonance effect, potentially explaining cosmic-ray excesses observed in recent experiments.

Contribution

It introduces a novel mechanism involving a Breit-Wigner tail near a resonance pole to account for increased dark matter annihilation signals.

Findings

Enhanced annihilation in galactic halo due to Breit-Wigner tail

Potential explanation for cosmic-ray excesses

Provides a new theoretical framework for dark matter signals

Abstract

We point out that annihilation of dark matter in the galactic halo can be enhanced relative to that in the early universe due to a Breit-Wigner tail, if the dark matter annihilates through a pole just below the threshold. This provides a new explanation to the "boost factor" which is suggested by the recent data of the PAMELA, ATIC and PPB-BETS cosmic-ray experiments.