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synchrotron radiation

(Encyclopedia)synchrotron radiation, in physics, electromagnetic radiation emitted by high-speed electrons spiraling along the lines of force of a magnetic field (see magnetism). Depending on the electron's energy ...

Cerenkov radiation

(Encyclopedia)Cerenkov radiation: see Cherenkov radiation. ...

Van Allen radiation belts

(Encyclopedia)CE5 Van Allen radiation belts: The solar wind, a stream of protons, electrons, and ions coming from the sun, gives the belts their asymmetrical shape. Van Allen radiation belts, belts of radiation...

actinometer

(Encyclopedia)actinometer ăkˌtənŏmˈətər [key], instrument used to measure the heating power of radiation. Actinometers are used chiefly in meteorology to measure solar radiation as transmitted directly by th...

bolometer

(Encyclopedia)bolometer bōlŏmˈətər, bə– [key], instrument for detecting and measuring radiation, e.g., visible light, infrared radiation, and ultraviolet radiation, in amounts as small as one millionth of a...

blackbody

(Encyclopedia)blackbody, in physics, an ideal black substance that absorbs all and reflects none of the radiant energy falling on it. Lampblack, or powdered carbon, which reflects less than 2% of the radiation fall...

Peters, Vera

(Encyclopedia)Peters, Vera (Mildred Vera Peters), 1911–93, Canadian radiation oncologist and clinical investigator, b. Rexdale, Ont., M.D. Univ. of Toronto, 1934. Beginning in 1935, she studied the treatment of H...

radiology

(Encyclopedia)radiology, branch of medicine specializing in the use of X rays, gamma rays, radioactive isotopes, and other forms of radiation in the diagnosis and treatment of disease. X ray machines and fluoroscop...

Tamm, Igor Yevgenyevich

(Encyclopedia)Tamm, Igor Yevgenyevich, 1895–1971, Soviet physicist, Ph.D. Moscow State Univ., 1933. He was a researcher at the P. N. Lebedev Physical Institute in Moscow from 1934 until his death in 1971. Tamm an...

ionization chamber

(Encyclopedia)ionization chamber, device for the detection and measurement of ionizing radiation. It consists basically of a sealed chamber containing a gas and two electrodes between which a voltage is maintained ...