High perveance electron gun for the electron cooling system

The cooling time in the electron cooling system is inversely proportional t o the beam current. To obtain high current of the electron beam the control electrode of the gun is provided with a positive potential and an electros tatic trap for secondary electrons appears inside the electron gun. This le ads to a decrease in the gun perveance. To avoid this problem, the adiabati c high perveance electron gun with the clearing control electrode is design ed in JINR (J. Bosser, Y. Korotaev, I. Meshkov, E. Syresin et al., Nucl. In str. and Meth. A 391 (1996) 103. Yu. Korotaev, I. Meshkov, A. Sidorin, A. S mirnov, E. Syresin, The generation of electron beams with perveance of 3-6 mu A/V-3/2, Proceedings of SCHEF'99). The clearing control electrode has a transverse electric field, which clears secondary electrons. Computer simul ations of the potential map were made with RELAX3D computer code (C.J. Kost , F.W. Jones, RELAX3D User's Guide and References Manual). (C) 2000 Elsevie r Science B.V. All rights reserved.