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The velocity and number of the photo-electrons ejected by x-rays as a function of the angle of emission

Watson, E. C. (1927) The velocity and number of the photo-electrons ejected by x-rays as a function of the angle of emission. Physical Review, 30 (4). pp. 479-487. ISSN 0031-899X. doi:10.1103/PhysRev.30.479.

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Magnetic spectra of the electrons ejected by x-rays from thin metallic films at angles ranging from 0° to 180° with the direction of the x-ray beam have been obtained by the method of Robinson, de Broglie, and Whiddington. To the degree of accuracy of the measurements (one-half of one percent) the maximum velocity of ejection is exactly the same in all directions. With thin foils of the heavier elements the number of electrons leaving the foil with this maximum velocity in the various directions (determined by the intensity of the edges) is approximately the same. With radiators of small density, or with sputtered films so thin that Wentzel's criterion for "single" scattering holds, the number of electrons leaving the foil is greatest in a direction a little forward of perpendicular to the direction of the x-ray beam. Rutherford's theory of nuclear scattering applied to electrons gives an explanation of these results if the assumption is made that all the electrons start out from the atom in the same direction.

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Additional Information:©1927 The American Physical Society. Received 14 June 1927. Finally the writer desires to express his thanks to Dr. I.S. Bowen for his kind assistance many times in maintaining constant conditions during the long and tedious exposures necessary in this work; to Dr. R.M. Badger for sputtering the gold films used; to Mr. J.A. Van den Akker for his care in making the reproductions which accompany this article; and to Professor R.A. Millikan for his enthusiastic interest and constant encouragement during the course of the work. The investigation has been carried out with the aid of funds provided by the Carnegie Corporation of New York.
Issue or Number:4
Record Number:CaltechAUTHORS:WATpr27
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:7230
Deposited By: Tony Diaz
Deposited On:23 Jan 2007
Last Modified:08 Nov 2021 20:40

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