Main parameters of a coaxial electrostatic lens

Coaxial electrostatic lenses are used in combination with a magnetic field in plasma-optical and manometric devices A. I. Morozov and S. V. Lebedev, in Reviews of Plasma Physics, Vol. 8, M. A. Leontovich (ed.), Consultants Bureau, New York (1980); V. P. Afanas’ev, A. A. Vydrik, L. P. Ovsyannikova, and E. V. Shpak, Sov. Phys. Tech. Phys. 25, 1049 (1980)]. Their employment in systems for transporting beams of high-energy charged particles is also known P. Krejcik, B. V. King, and I. C. Kelly, Optik (Stuttgart) 55, 385 (1980)], since, along with quadrupole lenses, they have a large optical strength. Expressions for the trajectories of charged low-energy particles were obtained by L. P. Ovsyannikova and S. V. Pasovets Sov. Phys. Tech. Phys. 32, 1422 (1987)] in the approximation of a rectangular field model with consideration of the variation of the energy at the entrance and exit from the field. The possibility, in principle, of focusing a parallel beam in a ring is demonstrated. Zh. Tekh. Fiz. 67, 81–82 (December 1997)