Composition | Elementary particle |
---|---|
Statistics | Fermionic |
Generation | First |
Interactions | Weak, Gravity |
Symbol | ν e |
Antiparticle | Electron antineutrino ( ν e) |
Theorized | Wolfgang Pauli (1930) |
Discovered | Clyde Cowan, Frederick Reines (1956) |
Mass | Small but non-zero. See neutrino mass. |
Electric charge | 0 e |
Color charge | No |
Spin | 1/2 |
Weak isospin | 1/2 |
Weak hypercharge | −1 |
Chirality | left-handed (for right-handed neutrinos, see sterile neutrino) |
The electron neutrino (
ν
e) is a subatomic lepton elementary particle which has no net electric charge. Together with the electron it forms the first generation of leptons, hence the name electron neutrino. It was first hypothesized by Wolfgang Pauli in 1930, to account for missing momentum and missing energy in beta decay, and was discovered in 1956 by a team led by Clyde Cowan and Frederick Reines (see Cowan–Reines neutrino experiment).
In the early 1900s, theories predicted that the electrons resulting from beta decay should have been emitted at a specific energy. However, in 1914, James Chadwick showed that electrons were instead emitted in a continuous spectrum.
In 1930, Wolfgang Pauli theorized that an undetected particle was carrying away the observed difference between the energy, momentum, and angular momentum of the initial and final particles.
On 4 December 1930, Pauli wrote a letter to the Physical Institute of the Federal Institute of Technology, Zürich, in which he proposed the electron neutrino as a potential solution to solve the problem of the continuous beta decay spectrum. An excerpt of the letter reads: