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500 Kilovolt Cathode Rays

Vollrath, R. E. (1931) 500 Kilovolt Cathode Rays. Physical Review, 38 (2). pp. 212-216. ISSN 0031-899X. doi:10.1103/physrev.38.212.

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The high potential x-ray tube at the California Institute has been modified so as to permit either x-rays or cathode rays to be produced. Electron currents up to 35 microamperes have been obtained through an aluminum window. A typical magnetic velocity spectrum of the high speed electrons passing out of an aluminum window is presented. The high velocity limit corresponds to about 500 kilovolts when the transformer voltage is 600 kilovolts peak. The velocity spectrum appears to be continuous and no absorption anomalies due to aluminum and lead foil are evident. The time required to obtain a velocity spectrum was reduced to a few minutes by allowing the electrons after being magnetically deflected, to pass through a copper foil into the air. The outside of the foil is coated with calcium tungstate and the photographic plate is placed in contact with the tungstate. It is noted that part of the photographic action of the high speed electrons is due to fluorescence of the glass backing of the photographic plates.

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Additional Information:© 1931 American Physical Society. Received 2 June 1931. National Research Fellow. The writer wishes to thank Professor Millikan for placing the facilities of the laboratory at his disposal.
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National Research CouncilUNSPECIFIED
Issue or Number:2
Record Number:CaltechAUTHORS:20200323-145949222
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:102061
Deposited By: Tony Diaz
Deposited On:23 Mar 2020 23:04
Last Modified:16 Nov 2021 18:08

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