Variable-Frequency Radially-Stable Micrometeoroid Accelerator

Abstract

A linear accelerator for micrometeoroids, employing a Wideröe-Sloan-Lawrence configuration, is described. The accelerator is operated in the radially-stable mode, and the frequency of the accelerating voltage is automatically adjusted to accept charged microspheres with q/m∼1−300 C/kg. The waveform applied is a ``drooping square wave'' which allows focusing adjustments to be made independent of frequency and phase. The change in phase over 93 gaps can be kept sufficiently small by proper selection of droop and other parameters so that acceleration occurs at all gaps. Injection is at 1.6 MV from a modified Van de Graaff. The linac adds an additional 9.3 MV. Speeds up to 70 km/sec should be reached with 0.1 μ diam microspheres.