V-PXB ELECTRON LINEAR-ACCELERATOR WITH TE-WAVE ASSISTED BY PLASMA FORBEAM STABILIZATION

The V-p x B acceleration scheme with the use of a transverse electroma gnetic wave is demonstrated experimentally, in which a pre-ionized pla sma is supplemented for obtaining a stable electron beam. The slow wav e structure employed here is a dielectric loaded waveguide, and an ele ctron beam in the accelerator induces surface charges on the dielectri c. The electron beam on account of acceleration also produces a dilute plasma to neutralize the surface charges. An initial energy gain of 2 .5 keV for the electron beam is observed from an incident energy of 60 keV without any external vertical magnetic field. When an external ve rtical magnetic field of 1.5 G is applied under the same conditions fo r performing the V-p x B scheme, an additional 1.5 keV energy gain is observed. (C) 1998 Elsevier Science B.V. All rights reserved.