This is exactly how physicists from the KATRIN collaboration put new constraints on the neutrino mass. As a result, their mass is usually measured indirectly by studying the velocity distribution of other particles participating in certain interaction or decay processes.
![electron neutrino mass electron neutrino mass](http://www7b.biglobe.ne.jp/~kcy05t/zu/neut/neu11.gif)
Neutrinos are difficult to study because their interactions with other particles are very weak - a single neutrino moving at nearly the speed of light will need a one hundred light year–thick layer of water to get scattered (and therefore detected).
![electron neutrino mass electron neutrino mass](https://i.pinimg.com/originals/87/98/3d/87983d1ef455a6ef1034f9ec8fbe6be6.gif)
Gaining a more precise measurement of the neutrino mass could therefore help shed light on the origin of particle masses. A neutrino’s mass is at least six orders of magnitude smaller than the mass of any other particle we have discovered, and such a huge gap hints that a different mass creation mechanism may be at play. In the Standard Model of particle physics, neutrinos are considered massless, but this non-zero mass challenges our current understanding and hints at a concept called “new physics” - physics beyond the Standard Model that could help clarify some of its discrepancies.Īll massive fundamental particles that we know of - from electrons with mass of half of a megaelectron volt (MeV) to 170 GeV t-quarks - obtain their masses through interactions with the Higgs boson.
![electron neutrino mass electron neutrino mass](https://www.symmetrymagazine.org/sites/default/files/styles/2015_hero/public/images/standard/60seconds_neutrinoMasses.png)
Neutrinos are abundant in the universe and, despite their small size, play an important role in the evolution of large-scale structures in it, such as galaxy formation.Ī direct laboratory measurement of the neutrino mass would have far-reaching implications in both elementary particle physics and cosmology. Physicists participating in the international Karlsruhe Tritium Neutrino (KATRIN) experiment have just measured the mass of a neutrino with a record-breaking accuracy.Īmong all known subatomic particles with non-zero masses, neutrinos are the lightest with a mass around ten million times less than that of an electron.