Direct Detection Constraints on Dark Matter Event Rates in Neutrino Telescopes, and Collider Implications

Abstract

Neutrino telescopes are looking to detect neutrinos produced by the annihilation of weakly interacting massive particle (WIMP) dark matter in the sun. The event rate depends on the dark matter density in the sun, which in turn is dictated by the cross section of WIMPs with nucleons. This however is bounded by direct detection experiments. We use the constraints from these experiments to place model-independent upper bounds on the event rates in neutrino telescopes that apply to any elastic dark matter model. Since the spin-independent WIMP-nucleon cross section is much more tightly constrained than the corresponding spin-dependent cross section, the bounds are much stronger in the former case and are competitive with the current limits from IceCube. If the number of events observed in neutrino telescopes exceeds the upper bound corresponding to spin-independent interactions, the implication is that the cross section of dark matter with nucleons is dominated by spin-dependent interactions. In such a scenario the natural dark matter candidates are Majorana fermions and real vector bosons, so that dark matter particles are their own anti-particles. We show that any such theory that leads to observable event rates at current generation neutrino telescopes will in general contain new particles charged under the Standard Model gauge groups that naturally lie in a mass range that is kinematically accessible to the Large Hadron Collider (LHC).