For many, the thrill comes from trying to narrow it down. Maybe the neutrino masses are the interplay of the Higgs boson and this new source of mass. Maybe there’s another source of mass that we do not know about. Physicists have proposed hundreds of theories for how neutrinos might get their mass, and everyone has their favorite. But neutrinos don’t seem to follow that trend. All other fermions, such as leptons and quarks, gain their mass through their interactions with the Higgs boson. Neutrinos are a type of fundamental particle known as a fermion. This feat is only possible because they have non-zero mass. And they don’t stick to just one of those flavors they oscillate from flavor to flavor as they move through space. We’ve got many experiments that detect their interactions, but we know relatively little about them.” “Because they’re so weakly interacting, we don’t know as much about neutrinos as other Standard Model particles,” says Jessica Turner, a postdoc studying neutrino phenomenology at the US Department of Energy’s Fermi National Accelerator Laboratory. Trillions of neutrinos pass harmlessly through your body each second, and in fact, rarely interact with any matter at all. So now we know: Neutrinos aren’t massless, they’re just incredibly light-a million times lighter than the next lightest particle, the electron. That means that there’s some ingredient missing.” “This was the first observed phenomenon that we didn’t know how to explain,” says André de Gouvêa, a theoretical physicist and professor at Northwestern University. In experiments, neutrinos appeared to move at the speed of light, something only a massless particle can accomplish.īut then, physicists at the Super-Kamiokande Observatory in Japan collected the first evidence that neutrinos had a mass that was tiny but not zero. The Standard Model, the theoretical framework that should explain ordinary matter and its interactions, predicted that particles called neutrinos had no mass. In 1998, researchers made a discovery that challenged their understanding of particle physics and vaulted an unassuming particle into the spotlight for decades to come.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |