Constraining WIMP Dark Matter with Dwarf Spheroidal Galaxies

With a large piece of our cosmos missing, the hunt is on for a viable dark matter candidate. The simplest approach is that of a weakly-interacting massive particle, where a single field is added to the Standard Model such that its mass and relic density from thermal freeze-out completes the dark matter puzzle in one fell swoop. The particle candidates considered in this model are electroweak multiplets, of which the triplet (the wino) at a mass of 2.8 TeV and the quintuplet at a mass of 13.6 TeV are studied in this work. Because the wino and quintuplet experience Standard Model gauge interactions, their annihilations create nearly monochromatic gamma-ray photons, making them excellent indirect detection targets. We report limits on the wino and quintuplet annihilation rates, each with their own range of masses using 638 hours of observation time on 17 dwarf spheroidal galaxies by the VERITAS imaging atmospheric Cherenkov telescope array.