neutron

Also known as N, n, neutrons

A neutron is a subatomic particle, symbol or , that has no electric charge, and a mass slightly greater than that of a proton. The neutron was discovered by James Chadwick in 1932, leading to the discovery of nuclear fission in 1938, the first self-sustaining nuclear reactor (Chicago Pile-1, 1942), and the first nuclear weapon (Trinity, 1945).

AI overview

A neutron is a tiny particle with no electric charge that is slightly heavier than a proton and makes up part of an atom's nucleus. Neutrons matter because their discovery in 1932 led to major developments including nuclear fission, the first nuclear reactor, and nuclear weapons.

AI-generated from the Wikipedia summary — may contain errors.

Key facts

Particle.classification: Baryon
Particle.name: Neutron
Particle.image: 250px
Particle.caption: The quark content of a neutron. The color assignment of individual quarks is arbitrary, but all three colors must be present. Forces between quarks are mediated by gluons.
Particle.group: Hadron
Particle.composition: 1 up quark, 2 down quarks
Particle.statistics: Fermionic
Particle.interaction: Gravity, weak, strong, electromagnetic
Particle.antiparticle: Antineutron
Particle.theorized: Ernest Rutherford (1920)
Particle.discovered: James Chadwick (1932)
Particle.symbol: , ,
Particle.mean_lifetime: (free)
Particle.electric_charge: (experimental limits)
Particle.electric_dipole_moment: < (experimental upper limit)
Particle.magnetic_moment: Neutron magnetic moment| J·T−1
Particle.spin:  ħ
Particle.isospin: −

via Wikipedia infobox

Research

44,330 papers

Neutron brachytherapy in the modern era: Indications and evidence.Cancer radiotherapie : journal de la Societe francaise de radiotherapie oncologique · 2023Loap P, Barcellini A, de Marzi L et al.DOI: 10.1016/j.canrad.2022.08.010
Neutron dose and its measurement in proton therapy-current State of Knowledge.ReviewThe British journal of radiology · 2020Hälg RA, Schneider UDOI: 10.1259/bjr.20190412
An investigation into neutron-induced bystander effects: How low can you go?ReviewEnvironmental research · 2019Lad J, Rusin A, Seymour C et al.DOI: 10.1016/j.envres.2019.04.033
Neutron radiotherapy for malignant gliomas.ReviewAmerican journal of clinical oncology · 1989Griffin BR, Berger MS, Laramore GE et al.DOI: 10.1097/00000421-198908000-00007
Neutron dose from a 6-MV X-ray beam in radiotherapy.Radiological physics and technology · 2023Matsubara HDOI: 10.1007/s12194-023-00705-6
Neutron relative biological effectiveness in Hiroshima and Nagasaki atomic bomb survivors: a critical review.ReviewJournal of radiation research · 2016Sasaki MS, Endo S, Hoshi M et al.DOI: 10.1093/jrr/rrw079
Neutron microscopy. The low-damage imaging of specialized organic materials.ReviewCell biophysics · 1985Steinbach ADOI: 10.1007/BF02788636
Neutron dosimetry in low-earth orbit using passive detectors.ReviewRadiation measurements · 2001Benton ER, Benton EV, Frank AL et al.DOI: 10.1016/s1350-4487(01)00047-6

via PubMed

Wikidata facts

Mass: 1.008966491595
Image: Neutron quark structure.svg

Show 18 more facts

Monte Carlo Particle Number: 2112
parity quantum number: 1
Commons category: Neutrons
spin quantum number: 0.5
isospin quantum number: 0.5
g-factor: -3.8260845
gyromagnetic ratio: 183247172
atomic number: 0
neutron number: 1
mean lifetime: 878.4
half-life: 10.183
magnetic moment: -1.9130427
electric charge: -0.0000000000000000000002
mass excess: 8071.31713
binding energy: 0
time of discovery or invention: 1932-00-00
electric dipole moment: 0.000000000000000000000000018
Stack Exchange tag: astronomy.stackexchange.com/tags/neutrons

Sources (7)

via Wikidata · CC0

~43 min read

Article

31 sections

Contents

Discovery
Occurrence
Atomic nucleus
Free neutron
Dineutrons and tetraneutrons
Neutron stars and neutron matter
Composition
Beta decay
Properties
Mass
Spin
Magnetic moment
Electric charge
Electric dipole moment
Antineutron
Detection
Neutron detection by neutron capture
Neutron detection by elastic scattering
Sources and production
Neutron beams and modification of beams after production
Applications
Nuclear energy
Other uses
Medical therapies
Health risks
Neutron temperature
See also
Neutron sources
Processes involving neutrons
References
Further reading

Neutrons are found, together with a similar number of protons in the nuclei of atoms. Atoms of a chemical element that differ only in neutron number are called isotopes. Free neutrons are produced copiously in nuclear fission and fusion. They are a primary contributor to the nucleosynthesis of chemical elements within stars through fission, fusion, and neutron capture processes. Neutron stars, formed from massive collapsing stars, consist of neutrons at the density of atomic nuclei but a total mass more than the Sun.