Ten-Year Search Finds No Signs of Dark Matter Annihilation

Dark matter constitutes roughly 85% of the matter in the Universe and yet stubbornly refuses to reveal its true identity. One leading candidate for dark matter is a hypothetical particle known as the weakly interacting massive particle (WIMP). When two WIMPs collide, they may annihilate and release other particles, including gamma-ray photons. Now, researchers from the High Energy Stereoscopic System (H.E.S.S.) Collaboration report that their ten-year search for WIMP gamma rays coming from the center of our Galaxy has come up empty. The team does, however, place the best constraints to date on the cross sections for WIMP annihilation, which should help researchers ferret out plausible candidates from a sea of possibilities.