The Highest-Energy Neutrino Event Constrains Dark Matter–Neutrino Interactions
What it is about
KM3NeT detected a neutrino of about 100 PeV, by some margin the most energetic ever observed. It crossed a great deal of dark matter on its way to us, and if the two interact it should have been scattered or absorbed en route, so its arrival is itself informative. We work out what it implies, and the resulting constraint is competitive with far more elaborate searches.
