A Sloan-Lawrence Accelerator with Self-Focusing Accelerating Structure

It has been shown in the preceding paper tnat focusing in a linear accelerator with drift tubes can be achieved if the shape of the extremities of the drift tubes is suitably chosen(l). We have set out to build a low energy prototype of an ion accelerator in which the results obtained theoritically are exploited . With the focusing system described above, a current gain of about ten times to the unfocused machine was obtained. Without any preliminary bunching device, the output to input current ratio is as high as 10% in good agreement with theory.