The search for a new type of neutrino turns up empty

The IceCube experiment, a particle detector at the South Pole that uses the ice itself to measure neutrinos, has shown that (hints of an elusive fourth type of neutrino) were probably just a mirage. After a years of analysis, researchers haven’t found anything. “We don’t see this—unfortunately, actually,” says principal investigator Francis Halzen. “I wish we had.”