Neutrino

Contrary to what the name might suggest, the neutrino (denoted by the Greek letter ν) is not a kind of mini-neutron, but a particle that is closely related to the electron. Like the neutron, the neutrino has no charge, but its mass is about a billion times smaller than that of the neutron.

The neutrino hardly interacts with matter. The half-value thickness of water for 1 MeV neutrinos is 10¹⁹ m, which is the unimaginably far distance light travels in 1000 years.

History

The neutrino was postulated in 1930 by the Austrian physicist Wolfgang Ernst Pauli (1900 – 1958). Its existence was first demonstrated in 1956 by the American physicists Clyde Lorraine Cowan (1919 – 1974) and Frederick Reines (1918 – 1998).

The name is the Italian equivalent of "little neutral one" and was jokingly coined in order to distinguish this light neutral particle from the heavy neutron.

Related concepts

• activity
• atom
• decay constant
• electromagnetic radiation
• electron
• half-life
• molecule
• neutron
• nuclear decay
• positron
• proton
• X-radiation