Astron Mechanical Engineering Effort

The two major components of the Astron machine, namely, the accelerator and main chamber, have been modified. In two successive steps the accelerator has been increased in energy from 4 MeV to 5 MeV and then from 5 MeV to 6 MeV with a final beam current of approximately 800 amps. This increased energy required a major modification to the radiation shielding. Additional hardware and refined diagnostics have been added to the accelerator to improve its performance. Among these is a unique on-line energy analyzer, a 60 MHz R. F. modulator, a new method for measuring current and beam position, and the use of titanium to minimize sparking in the electron gun. Optimization of the beam transport included redesign of the solenoid magnets and the installation of a sixty-five ft long continuous solenoid. Main chamber changes include the repair and installation of both cantilevers with the addition of a device to bridge between the cantilevers. New geometric arrangements have been made to the static resistors, which are part of the E-layer trapping mechanism. A method for quickly and accurately measuring the magnitude and configuration of the magnetic field for the main chamber solenoid will also be described.