Leptonic Indirect Detection Signals from Strongly Interacting Asymmetric Dark Matter

TL;DR

This paper proposes a strongly-interacting, TeV-scale asymmetric dark matter model that explains cosmic electron-positron excesses through late-time annihilations into leptons, linking dark matter relic abundance to baryon asymmetry.

Contribution

It introduces a novel strongly-coupled dark matter model with lepton number transfer and oscillations, connecting dark matter properties to matter-antimatter asymmetry.

Findings

Dark matter annihilates into leptons via dark sector decay channels.

The model naturally reproduces the observed dark matter abundance.

Late-time oscillations enable current annihilations consistent with cosmic ray excesses.

Abstract

Particles with TeV mass and strong self-interactions generically have the right annihilation cross section to explain an observed excess of cosmic electrons and positrons if the end-product of the annihilation is charged leptons. We present an explicit model of strongly-coupled TeV-scale dark matter whose relic abundance related to the matter-antimatter asymmetry of the observed universe. The B - L asymmetry of the standard model is transfered to the dark sector by an operator carrying standard model lepton number. Lepton number violation naturally induces dark matter particle-antiparticle oscillations at late times, allowing dark matter-antimatter annihilations today. The dark matter annihilates into lighter strongly-interacting particles in the dark sector that decay to leptons via the transfer operator. The strong dynamics in the dark sector is at the weak scale due to supersymmetry breaking. The correct dark matter abundance is automatically obtained for natural values of dimensionless parameters, analogous to the situation for conventional WIMPs.