File:Cyclotron diagram.png

Original file(1,004 × 498 pixels, file size: 73 KB, MIME type: image/png)


English: Diagram of a cyclotron, a particle accelerator invented by Earnest O. Lawrence in 1932 and widely used from the 1930s to the 1950s. It consists of a pair of "D" shaped sheet metal electrodes called "Dees" placed face to face inside a vacuum chamber, between the poles of an electromagnet. An oscillating radio frequency voltage of several thousand volts is applied to the dees. Atomic particles to be accelerated, such as protons are released in the center. The magnetic field causes them to travel in a spiral path from the center to the rim of the dees, being accelerated each time they pass from one electrode to the other. When the particles reach the rim they pass out of the dees through a small gap and strike a target. In this diagram the electromagnet pole pieces are not shown full size; they must be at least as big as the dees to create a uniform field.

Caption: How the cyclotron works. Size of the magnets has been kept down to show the path of the electron
Source Retrieved November 3, 2014 from Radio-Craft, Radcraft Publications, Springfield, Massachusetts, Vol. 18, No. 9, June 1947 p. 23 on American Radio History archive
Author Unknown
(Reusing this file)
This 1947 issue of Radio-Craft magazine would have the copyright renewed in 1975. Online page scans of the Catalog of Copyright Entries, published by the US Copyright Office can be found here. [1] Search of the Renewals for Periodicals for 1974, 1975, and 1976 show no renewal entries for "Radio-Craft". Therefore the magazine's copyright was not renewed and it is in the public domain.


Public domain
This work is in the public domain because it was published in the United States between 1925 and 1963 and although there may or may not have been a copyright notice, the copyright was not renewed. Unless its author has been dead for the required period, it is copyrighted in the countries or areas that do not apply the rule of the shorter term for US works, such as Canada (50 pma), Mainland China (50 pma, not Hong Kong or Macao), Germany (70 pma), Mexico (100 pma), Switzerland (70 pma), and other countries with individual treaties. See Commons:Hirtle chart for further explanation.

Deutsch | English | español | français | galego | italiano | 日本語 | 한국어 | македонски | português | português do Brasil | русский | sicilianu | українська | 中文(台灣)‎ | +/−

Flag of the United States

File history

Click on a date/time to view the file as it appeared at that time.

current12:51, 27 November 2014Thumbnail for version as of 12:51, 27 November 20141,004 × 498 (73 KB)ChetvornoUser created page with UploadWizard
The following pages on the English Wikipedia use this file (pages on other projects are not listed):

Global file usage

The following other wikis use this file: