Editing Neutron diffraction (section)

=== Discovery of the neutron ===
{{main|Neutron#Discovery}}

In 1921, American chemist and physicist [[William Draper Harkins|William D. Harkins]] introduced the term "[[neutron]]" while studying [[atomic structure]] and [[Nuclear reaction|nuclear reactions]]. He proposed the existence of a neutral particle within the [[atomic nucleus]], though there was no experimental evidence for it at the time.<ref>{{Cite journal |last=Harkins |first=William D. |date=1917 |title=The evolution of the elements and the stability of complex atoms. A new periodic system which shows a relation between the abundance of the elements and structure of the nuclei of atoms. |url=https://pubs.acs.org/doi/abs/10.1021/ja02250a002 |journal=Journal of the American Chemical Society |language=en |volume=39 |issue=5 |pages=856–879 |doi=10.1021/ja02250a002 |issn=0002-7863|url-access=subscription }}</ref> In 1932, British physicist [[James Chadwick]] provided experimental proof of the neutron's existence. His discovery confirmed the presence of this neutral [[subatomic particle]], earning him the [[Nobel Prize in Physics]] in 1935. Chadwick's research was influenced by earlier work from [[Irène Joliot-Curie|Irène]] and [[Frédéric Joliot-Curie]], who had detected unexplained neutral [[radiation]] but had not recognized it as a distinct particle.<ref>{{Cite journal |date=1932 |title=The existence of a neutron |url=https://royalsocietypublishing.org/doi/10.1098/rspa.1932.0112 |journal=Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character |language=en |volume=136 |issue=830 |pages=692–708 |doi=10.1098/rspa.1932.0112 |bibcode=1932RSPSA.136..692C |issn=0950-1207 |last1=Chadwick |first1=J. |doi-access=free }}</ref> Neutrons are subatomic particles that exist in the nucleus of the atom, it has higher mass than protons but no electrical charge.

In the 1930s [[Enrico Fermi]] and colleagues gave theoretical contributions establishing the foundation of [[neutron scattering]]. Fermi developed a framework to understand how neutrons interact with atomic nuclei.<ref>{{Cite journal |last1=Amaldi |first1=E. |last2=Fermi |first2=E. |date=1936-11-15 |title=On the Absorption and the Diffusion of Slow Neutrons |url=https://link.aps.org/doi/10.1103/PhysRev.50.899 |journal=Physical Review |language=en |volume=50 |issue=10 |pages=899–928 |doi=10.1103/PhysRev.50.899 |bibcode=1936PhRv...50..899A |issn=0031-899X|url-access=subscription }}</ref>