Standard Free-Air Chamber for the Measurement of Low Energy X-rays (20 to 100 Kilovolts-Constant-PotentiaIY
نویسنده
چکیده
A description of the new N a t ional Bureau of Standards " low" en ergy free-air chamber is given. The standard chamber is designed to mea sure t l1e expos ure dose II: roe ntgens for X-ray beams generated at pote ntials fr ol11. 20 to 100 kIi ovolts-co nstant-poten tJaI (kvcp) '':Ith filtration s ranging from 2 millimet e rs of bery lli um to 2 mIi lune ters of b ery l hum plus 41m 11Ime ters of aluminum. The chamber has been compared wIth the N a tIOnal Bureau of Standards " medium" energy standard a t 60, 75, and 100 kvcp with filtration s of 8 , 3, and 4 millime ters of a luminum, respectively . The t \\·o standa rd chambers agreed to \\"lth ln 0.3 p ercent.
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