Dark Matter Annihilation Limits from Dwarf Galaxies using VERITAS

TL;DR

This paper reports on VERITAS telescope observations of dwarf galaxies to set limits on dark matter annihilation, introducing new statistical methods to improve constraints on WIMP dark matter models.

Contribution

It presents new observational data and statistical techniques for constraining WIMP dark matter properties using gamma-ray observations of dwarf galaxies.

Findings

No significant gamma-ray excess detected from dwarf galaxies.

Stronger limits on WIMP annihilation cross-section established.

Enhanced statistical analysis improves sensitivity of dark matter searches.

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 of 50 GeV to greater than 10 TeV. Nearby dwarf spheroidal galaxies (dSphs) are expected to contain a high density of DM 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 Standard Model (SM) particles. The VERITAS array of Imaging Atmospheric Cherenkov Telescopes (IACTs), sensitive to gamma rays in the 100GeV to 50 TeV range, carries out an extensive observation program of dSphs. Presented here are results of the observations and new statistical techniques for constraining properties of WIMP DM models.