CERN Accelerating science

Article
Title	Characteristics of Electron Beam Produced by Magnetron Diode with a Secondary-Emission Cathode
Author(s)	Reshetnyak, Nikolay ; Aizatsky, Nikolay ; Dovbnya, Anatoly N ; Dovbnya, Natalya ; Mytrochenko, Viktor ; Zakutin, Valeriy
Affiliation	(NSC/KIPT, Kharkov)
Publication	2005
In:	21st IEEE Particle Accelerator Conference, Knoxville, TN, USA, 16 - 20 May 2005, pp.3197
Subject category	Accelerators and Storage Rings
Abstract	The beam parameters were investigated using an azimuth-sectionalized 8-channel Faraday cup and a 12-channel computer-aided measuring system. The magnetron diode had a cathode (40 mm in diameter) and a 15 mm anode-cathode gap. At a cathode voltage amplitude of 50 kV and a cathode magnetic field of  1200 Oe, the diode generates a tubular electron beam with an outer diameter of 50 mm, an inner diameter of 44 mm, a beam current of  50 A. The short time instability of the total beam current, and of the current from each of eight segments of the Faraday cup was estimated to be  2 … 3%, and long time instability (3 hours) was 5 7 %. Azimuthal distribution of beam current was investigated versus the amplitude, distribution and direction of the magnetic field. At a cathode magnetic field of 1200 Oe, that falls off inhomogeneity in the vicinity of the Faraday cup down to  800 Oe, the azimuthal beam current distribution has a ± (3 … 5)%. As the magnetic field strength increases up to  1700 Oe in the region of beam emergence from the gun and the Faraday cup, the azimuthal inhomogeneity of the beam current increases up to ± (100 … 150)%.