neutrino (redirected from Electron-neutrino)

neu·tri·no  (n-trn, ny-)

n. pl. neu·tri·nos

Any of three electrically neutral subatomic particles in the lepton family. See Table at subatomic particle.

---

[Italian, from neutro, neuter, from Latin neuter, neutr-; see neuter.]

---

neutrino [njuːˈtriːnəʊ]

n pl -nos

(Physics / General Physics) Physics a stable leptonic neutral elementary particle with very small or possibly zero rest mass and spin ½ that travels at the speed of light. Three types exist, associated with the electron, the muon, and the tau particle

[from Italian, diminutive of neutrone neutron]

---

neutrino  (n-trn)

Any of three electrically neutral subatomic particles with extremely low mass. These include the electron-neutrino, the muon-neutrino, and the tau-neutrino. The study of neutrinos that come to the earth as cosmic rays suggests that neutrinos can transform into each other in a process called neutrino oscillation. For this phenomenon to be theoretically possible, the three neutrinos must have distinct masses; for this reason, many scientists believe that they have mass. See Table at subatomic particle.

A Closer Look Neutrinos were not observed until 1955, roughly a quarter of a century after the physicist Wolfgang Pauli first hypothesized their existence on theoretical grounds. Pauli was studying certain radioactive decay processes called beta decay, processes now known to involve the decay of a neutron into a proton and an electron. A certain amount of energy that was lost in these processes could not be accounted for. Pauli suggested that the energy was carried away by a very small, electrically neutral particle that was not being detected. (He originally wanted to name the particle a neutron but didn't publish the suggestion, and a few years later the particle we now know as the neutron was discovered and named in print. The Italian physicist Enrico Fermi then coined the term neutrino, which means "little neutron" in Italian.) Neutrinos are hard to detect because their mass, if they indeed have any, is extremely low, and they possess no electric charge; a chunk of iron a few light-years thick would absorb only about half of the neutrinos that struck it. Nevertheless, neutrinos can be detected, and three different types have been distinguished, each of which is associated with a particular lepton (the electron, the muon, and the taon) with which it is often paired in interactions involving the weak force. Recent analysis of neutrinos emanated by the Sun has suggested that each type of neutrino can spontaneously turn into one of the others in a process of neutrino oscillation, and for theoretical reasons this in turn would require that neutrinos have mass. If so, then despite their light weight, their abundance may in fact mean that neutrinos contribute significantly to the overall mass of the universe.

Thesaurus

Noun

1.

neutrino - an elementary particle with zero charge and zero mass lepton - an elementary particle that participates in weak interactions; has a baryon number of 0

Translations

neutrino

n → Neutrino nt

neutrino [njuːˈtriːnəʊ] n → neutrino