Betatron

One of the first betatrons built by Donald Kerst (visible right) at University of Illinois, 1940. Its 4-ton magnet could accelerate electrons to 24 MeV.
A German 6 MeV betatron (1942)
A 35 MeV betatron used for photonuclear physics at the University of Melbourne.

A betatron is a type of cyclic particle accelerator for electrons. It consists of a torus-shaped vacuum chamber with an electron source. Circling the torus is an iron transformer core with a wire winding around it. The device functions similarly to a transformer, with the electrons in the torus-shaped vacuum chamber as its secondary coil. An alternating current in the primary coils accelerates electrons in the vacuum around a circular path. The betatron was the first machine capable of producing electron beams at energies higher than could be achieved with a simple electron gun, and the first circular accelerator in which particles orbited at a constant radius.[1]

The concept of the betatron had been proposed as early as 1922 by Joseph Slepian.[2] Through the 1920s and 30s a number of theoretical problems related to the device were considered by scientists including Rolf Wideroe,[3][4] Ernest Walton, and Max Steenbeck.[5] The first working betatron was constructed by Donald Kerst at the University of Illinois Urbana-Champaign in 1940.[6][7][8]

  1. ^ "Betatron | particle accelerator". Encyclopedia Britannica. Retrieved 2019-01-24.
  2. ^ Kerst, Donald W. (January 1946). "Historical Development of the Betatron". Nature. 157 (3978): 90–95. Bibcode:1946Natur.157...90K. doi:10.1038/157090a0. PMID 21015096. S2CID 42153256.
  3. ^ Wideröe, R. (17 Dec 1928). "Über ein neues Prinzip zur Herstellung hoher Spannungen". Archiv für Elektrotechnik (in German). 21 (4): 387–406. doi:10.1007/BF01656341. S2CID 109942448.
  4. ^ Dahl, F. (2002). From nuclear transmutation to nuclear fission, 1932-1939. CRC Press. ISBN 978-0-7503-0865-6.
  5. ^ Steenbeck, Max (1943). "Beschleunigung von Electronen durch elektrische Wirbelfelder". Die Naturwissenschaften. 31 (S): 234–235. Bibcode:1943NW.....31..234S. doi:10.1007/BF01482241. S2CID 6832156.
  6. ^ Kerst, D. W. (1940). "Acceleration of Electrons by Magnetic Induction". Physical Review. 58 (9): 841. Bibcode:1940PhRv...58..841K. doi:10.1103/PhysRev.58.841. S2CID 120616002.
  7. ^ Kerst, D. W. (1941). "The Acceleration of Electrons by Magnetic Induction" (PDF). Physical Review. 60 (1): 47–53. Bibcode:1941PhRv...60...47K. doi:10.1103/PhysRev.60.47.
  8. ^ Kerst, D. W.; Serber, R. (Jul 1941). "Electronic Orbits in the Induction Accelerator". Physical Review. 60 (1): 53–58. Bibcode:1941PhRv...60...53K. doi:10.1103/PhysRev.60.53.