Femtometre

From Infogalactic: the planetary knowledge core
Jump to: navigation, search

<templatestyles src="Module:Hatnote/styles.css"></templatestyles>

The femtometre (American spelling femtometer, symbol fm[1][2][3]) (Danish: femten, "fifteen"; Ancient Greek: μέτρον, metrοn, "unit of measurement") is an SI unit of length equal to 10−15 metres. This distance can also be called fermi and was so named in honour of physicist Enrico Fermi, as it is a typical length-scale of nuclear physics.

Definition and equivalents

1000 attometres = 1 femtometre = 1 fermi = 0.001 picometre = 1.0 × 10−15 metres

1,000,000 femtometres = 10 Ångström = 1 nanometre.

For example, the charge radius of a proton is approximately 0.84–0.87 femtometres[4] while the radius of a gold nucleus is approximately 8.45 femtometres.[citation needed]

1 barn = 100 fm2

History

The femtometre was adopted by the 11th Conférence Générale des Poids et Mesures, and added to SI in 1964.

The fermi is named after the Italian physicist Enrico Fermi (1901–1954), one of the founders of nuclear physics. The term was coined by Robert Hofstadter in a 1956 paper published in Reviews of Modern Physics entitled "Electron Scattering and Nuclear Structure".[5] The term is widely used by nuclear and particle physicists. When Hofstadter was awarded the 1961 Nobel Prize in Physics, it subsequently appears in the text of his 1961 Nobel Lecture, "The electron-scattering method and its application to the structure of nuclei and nucleons" (December 11, 1961).[6]

References

  1. REDIRECT Template:Metric units of length


  • This is a redirect from a page that has been moved (renamed). This page was kept as a redirect to avoid breaking links, both internal and external, that may have been made to the old page name. For more information follow the bold category link.de:Meter#Dezimale Vielfache

ru:Фемтометр