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A Velocity Filter for Electrons and Ions

Smythe, William R. (1926) A Velocity Filter for Electrons and Ions. Physical Review, 28 (6). pp. 1275-1286. ISSN 0031-899X. doi:10.1103/PhysRev.28.1275.

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If a charged particle, moving along the x-axis with a velocity v, encounters successively two identical alternating electric fields of frequency ν, which are everywhere perpendicular to the x-axis, it will emerge from the last field undisplaced and traveling in the original direction under the following conditions: (1) Each field has two similar halves whose distance between centers is a; (2) The distance between the fields, center to center, is D=sa/n, where s and n are odd integers; (3) The velocity of the particle is v_0=2aν/n. The distribution about the velocity v_0 is computed when particles enter and leave the system through slits of width y_0 on the x-axis. The results show that the emergent beam can be confined to a very narrow velocity range.

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Additional Information:© 1926 The American Physical Society. Received 16 July 1926; published in the issue dated December 1926. The author wishes to thank Dr. Bowen for valuable suggestions and Professor Epstein for checking some of the equations.
Issue or Number:6
Record Number:CaltechAUTHORS:20140107-134454414
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:43249
Deposited On:07 Jan 2014 22:09
Last Modified:18 Jan 2023 20:18

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