VERITAS Limits on Dark Matter Annihilation from Dwarf Galaxies

TL;DR

This paper reports on VERITAS gamma-ray observations of dwarf spheroidal galaxies, setting limits on dark matter annihilation models, especially focusing on the Segue 1 galaxy, to constrain properties of WIMP candidates.

Contribution

It provides new observational limits on dark matter annihilation from dwarf galaxies using VERITAS, including deep exposure data on Segue 1.

Findings

No significant gamma-ray excess detected.

Constraints placed on WIMP annihilation cross-sections.

Limits improve previous bounds on dark matter models.

Abstract

Current cosmological models and data suggest the existence of a Cold Dark Matter (DM) component, however the nature of DM particles remains unknown. A favored candidate for DM is a Weakly Interacting Massive Particle (WIMP) in the mass range from 50 GeV to greater than 10 TeV. Nearby dwarf spheroidal galaxies (dSph) are expected to contain a high density of Dark Matter with a low gamma-ray background, and are thus promising targets for the detection of secondary gamma rays at very high energies (VHE, E > 0.1 TeV) through the annihilation of WIMPS into SM particles. Presented here are recent VERITAS observations of dSph, including a deep exposure on Segue 1. Limits are derived for various annihilating and decaying dark matter particle models.