Investigation of Mechanisms Leading to Precision

of Intense Electron Beams

Mueller, Georg^a; Engelko, Vladimir^b; An, Wladimir^a; Bluhm, Hansjoachim^a;

Kuznetsov, Vladimir^b; Kovalev, Vladimir^b; Vyazmenova, Galya^b,

a- Forschungszentrum Karlsruhe, Institut für Hochleistungsimpuls- und Mikrowellentechnik,

Postfach 3640, D-76021 Karlsruhe, Germany

b- Efremov Institute of Electrophysical Apparatus, 196641, St. Petersburg, Russia

In previous work [1] it was shown that transportation of intense electron beams in vacuum by applied magnetic field leads to precision of the beam along the axis of the transport channel. The beam precision was investigated by different diagnostics (Faraday cups, small metal plates, x-ray detectors). It was found that frequency, amplitude and onset time of the beam precision strongly depends on magnitude and distribution of the applied magnetic field and on the target material. The mechanism of beam precision is quit complicated. The most probable cause of this beam rotation is the presence of radial electric field that must result in an azimuth beam drift. In this paper we present results of further experimental investigations devoted to clarify the reasons for appearance of beam precision. Experimental results are presented to estimate the relevance of ions spreading from the target into the beam.

This work was supported by ISTC (project No 975.2)

1. Mueller G.,Engelko V., Bluhm H., An V., Kuznetsov V., Viazmenova G. Proc. of the 14^th International Conference on Powerful Beams of Particles. Albuquerque, USA. 2002, pp. 337-340