Linear accelerator provided with self-focusing cavities having high electron capture efficiency in respect of moderate injection voltages

摘要

Good bunching and high electron capture efficiency of a first resonant cavity of an accelerator are combined with the self-focusing properties of said cavity associated with a following second cavity by modifying the law of the modulus of the electric field set up within said cavity, the amplitude of said field being greater within a first portion of the cavity than within a second portion. It is shown that the electrons are thus naturally bunched within the first portion of the cavity. In the second portion of the cavity, they are than subjected to acceleration and then to uniform focusing which includes entry into the following cavity. The result thereby achieved is to increase the capture efficiency and electron density of the beam which is accelerated from a low-voltage electron gun.