Radiation

Radiation

Radiation, as in physics, is energy in the form of waves or moving subatomic particles emitted by an atom or other body as it changes from a higher energy state to a lower energy state. Radiation can be classified as "ionizing" or "non-ionizing radiation", depending on its effect on atomic matter. The most common use of the word "radiation" refers to ionizing radiation. Ionizing radiation has enough energy to ionize atoms or molecules while non-ionizing radiation does not. "Radioactive material" is a physical material that emits ionizing radiation.

Types of Radiation

There are three principal types of ionizing radiation: alpha, beta and gamma radiation. They are all emitted from the nucleus of an unstable atom. Less commonly encountered are spontaneous nuclear fission, positron emission, and neutron emission. Electron capture results in the spontaneous emission of an X-ray. Certain isotopes of radium have a decay mode where they emit an entire 12C6 nucleus.

Discovery

Wilhelm Röntgen is credited with the discovery of X-Rays. When experimenting with various isotopes of tritium, he noticed a drastic change in photonic emissions when measuring electrical charges in a vacuum. When he took pictures of the tritium, he found that the state of one solid piece would deteriorate quickly. Henri Becquerel found that uranium salts caused fogging of an unexposed photographic plate, and Marie Curie discovered that only certain elements gave off these rays of energy. She named this behaviour radioactivity.

In December of 1899, Marie Curie and Pierre Curie discovered radium in pitchblende. This new element was two million times more radioactive than uranium, as described by Marie.

See also


* Ionizing radiation
* Non-ionizing radiation
* Background radiation, which actually refers to the background ionizing radiation
* Black hole
* Cosmic microwave background radiation, 3K blackbody radiation that fills the Universe
* Electromagnetic spectrum
* Radiant energy, radiation by a source into the surrounding environment.
* Radiation damage - adverse effects on materials and devices
* Radiation hormesis - dosage threshold damage theory
* Radiation poisoning - adverse effects on life forms
* Radiation hardening - making devices resistant to failure in high radiation environments
* Radioactive contamination
* Radioactive decay
* Hawking radiation
* Cherenkov radiation
* Cyclotron radiation
* Solar radiation
* Synchrotron radiation
* Radiation reaction
* National Council on Radiation Protection and Measurements

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  • radiation — 1. (ra di a sion) s. f. Terme didactique. Émission de rayons lumineux. L humidité de air, la radiation solaire, les phénomènes météoriques... , FLAMMARION, Feuilleton du Siècle (11 juin 1867).    Il se dit aussi de l émission du calorique. La… …   Dictionnaire de la Langue Française d'Émile Littré

  • Radiation — Saltar a navegación, búsqueda Radiation es el sexto album de la banda conocida como Marillion con el vocalista Steve Hogarth, El album fue tibiamente recibido por los fans debido a su sonido mas acústico y con muchas influencias de blues que han… …   Wikipedia Español

  • Radiation — Ra di*a tion (r[=a] d[i^]*[=a] sh[u^]n), n. [L. radiatio: cf. F. radiation.] 1. The act of radiating, or the state of being radiated; emission and diffusion of rays of light; beamy brightness. [1913 Webster] 2. The shooting forth of anything from …   The Collaborative International Dictionary of English

  • radiation — Radiation. s. f. Terme de Finances. Raye que l on passe sur quelque article d un compte pour le rendre nul. Cet article est sujet à radiation. radiation de compte. on a fait plusieurs radiations sur ses comptes …   Dictionnaire de l'Académie française

  • radiation — (n.) 1550s, from L. radiationem (nom. radiatio) a shining, radiation, noun of action from radiare to beam, shine, from radius beam of light (see RADIUS (Cf. radius)) …   Etymology dictionary

  • radiation — [rā΄dē ā′shən] n. [L radiatio] 1. the act or process of radiating; specif., the process in which energy in the form of rays of light, heat, etc. is sent out through space from atoms and molecules as they undergo internal change 2. the rays sent… …   English World dictionary

  • radiation — radiation. См. радиация. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • Radiation — (lat.), Strahlung, in der Astronomie und Meteorologie gewöhnlich für die Strahlung der Sonne gebraucht; Weiteres s. Sonne und Insolation. Durchstreichung eines Rechnungspostens mit sich kreuzenden Strichen …   Meyers Großes Konversations-Lexikon

  • Radiation — Radiation, vgl. Geothermik …   Lexikon der gesamten Technik

  • Radiation — Radiatiōn (lat.), Strahlung, insbes. Sonnenstrahlung (s.d.); auch Durchstreichung mit sich kreuzenden Strichen …   Kleines Konversations-Lexikon

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