Neutrons are components of the nucleus of atoms.

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Neutrons and its components

The neutron is a component of the nucleus of atoms and is made up of two down quarks and one up quark.

The up quark has +2/3 electrical charge. The down quarks each have a -1/3 electric charge. Therefore, neutrons have a resultant electric charge 0. (0 Coulomb)

Each neutron consists of a cluster of these three gluon-bound quarks (particles in which the strong nuclear interaction resides).

The neutron consists of 3 quarks. Credit: CPAN website,

Other characteristics of neutrons

The mass of the neutron is somewhat greater than that of the proton: 1,675×10-27 Kg.

Currently it is preferred to use the gigalectronvolt as the unit of mass; and the mass of the proton is said to be 0.0009383 GeV. The mass of the neutron is 0.0009396 GeV.

Outside the atomic nucleus, the neutron is unstable and has a half-life of about 15 minutes. As it disintegrates, it emits an electron and an antineutrino, after which it is converted into a proton.

The neutron interacts with the protons through the strong nuclear force, but without electromagnetic repulsion, since its electrical charge is zero.

The neutron is present in almost all atomic nuclei. The only exception is hydrogen, which does not have any neutrons in its nucleus.

neutrons Irène Curie
Marie Curie and Irène Joliot. Credit: web

The neutron was discovered in the 1930s, in Germany, France and England, thanks to the works of Walther Bothe and H. Becker, Irène Joliot-Curie and Frédéric Joliot, James Chadwick.

This particles have not electric charge

With the results obtained in their experiments, they deduced that it was necessary to accept that some of the particles detected in some of the radiation obtained had a mass very similar to that of the proton, but without an electric charge.

They thought that the neutron was the result of the union of a proton and an electron and that both formed a kind of electric dipole.

neutrons. Bothe
Walter Bothe, German sage. Credit: web

Other experiments carried out later, caused that the idea of ​​the dipole was discarded and established the nature of the neutrons, as it is accepted at the moment.

Neutrons are essential in nuclear reactions: when a neutron hits a fissile atom, a greater number of neutrons are produced, which in turn cause other chain fissions.

If this reaction occurs in a controlled way through the use of a moderator in the nuclear reactor, it is possible to take advantage of the developed nuclear energy.

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