#Calcium hollow cathode lamp free
Crookes tubes created free electrons by ionization of the residual air in the tube by a high DC voltage of anywhere between a few kilovolts and 100 kV. Many of the early Crookes tubes (invented around 1875) undoubtedly radiated X-rays, because early researchers noticed effects that were attributable to them, as detailed below. They were noticed by scientists investigating cathode rays produced by such tubes, which are energetic electron beams that were first observed in 1869. History Pre-Röntgen observations and research Example of a Crookes tube, a type of discharge tube that emitted X-raysīefore their discovery in 1895, X-rays were just a type of unidentified radiation emanating from experimental discharge tubes. X-rays are also used in ways such as checking for broken bones, detecting certain kinds of diseases, identification of some metals, and ascertaining the locations of weak points in steel. Spellings of X-ray(s) in English include the variants x-ray(s), xray(s), and X ray(s). He named it X-radiation to signify an unknown type of radiation. In many languages, X-radiation is referred to as Röntgen radiation, after the German scientist Wilhelm Conrad Röntgen, who discovered it on November 8, 1895. X-ray wavelengths are shorter than those of UV rays and typically longer than those of gamma rays. Most X-rays have a wavelength ranging from 10 nanometers to 10 picometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz ( 3 ×10 16 Hz to 3 ×10 19 Hz) and energies in the range 124 keV to 145 eV, respectively. X-ray radiation, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. William Coolidge explains medical imaging and X-rays. Note the edges of hollow cylinders as compared to the solid candle. Natural color X-ray photogram of a wine scene. Not to be confused with X-wave or X-band. For other uses, see X-ray (disambiguation). For the medical specialty, see Radiology. For the method of imaging, see Radiography. Sauf mention contraire ci-dessus, le contenu de cette notice bibliographique peut être utilisé dans le cadre d’une licence CC BY 4.0 Inist-CNRS / Unless otherwise stated above, the content of this bibliographic record may be used under a CC BY 4.0 licence by Inist-CNRS / A menos que se haya señalado antes, el contenido de este registro bibliográfico puede ser utilizado al amparo de una licencia CC BY 4.This article is about the nature, production, and uses of the radiation. 2009, Vol 42, Num 16ġ65001.1-165001.5 ref : 23 ref CODEN JPAPEH ISSN 0953-4075 Scientific domain Atomic molecular physics Publisher Institute of Physics, Bristol Publication country United Kingdom Document type Article Language English Keyword (fr) Calcium Modulateur acoustooptique Piégeage atome Piégeage optique Refroidissement par laser Spectrométrie absorption Transition niveau énergie 3230 3280P 3710 Saphir:Ti Keyword (en) Calcium Acoustooptical modulator Atom trapping Optical trapping Laser cooling Absorption spectroscopy Energy-level transitions Keyword (es) Modulador acústico-óptico Classification Pascal 001 Exact sciences and technology / 001B Physics / 001B30 Atomic and molecular physics / 001B30B Atomic properties and interactions with photons / 001B30B30 Atomic spectra Pascal 001 Exact sciences and technology / 001B Physics / 001B30 Atomic and molecular physics / 001B30B Atomic properties and interactions with photons / 001B30B80 Photon interactions with atoms / 001B30B80P Optical cooling of atoms trapping Pascal 001 Exact sciences and technology / 001B Physics / 001B30 Atomic and molecular physics / 001B30G Mechanical control of atoms, molecules and ions / 001B30G10 Atom, molecule and ion trapping and colling methods Discipline Atomic and molecular physics Origin Inist-CNRS Database PASCAL INIST identifier 21901619 Atomic, molecular and optical physics (Print). SUPA, Department of Physics, University of Strathclyde, John Anderson Building, 107 Rottenrow East, Glasgow G4 ONG, United Kingdom Source CopyPermanent link Copy Saturated absorption spectroscopy of calcium in a hollow-cathode lamp Author DAMMALAPATI, U 1 NORRIS, I 1 RIIS, E 1
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