BASIC PROCESSES OF ION BEAM TERMINATION
Abstract
Theoretical and empirical information necessary for the design of an electrical propulsion test facility collector system complex is compiled. Design considerations which include sputtering, beam accommodation, secondary emission, and less serious secondary effects, are considered in some detail. A theoretical model is presented which accounts for the energy dependence of the sputtering phenomena first at low ion energies and secondly in the region where the Bohr screening parameter is of the order of unity. Based on these functions obtained from the theoretical model in the two regions, an asymptotic empirical relation for the sputtering ratio as a function of ion energy is found to give a satisfactory account of available data. In addition, equations are developed to evaluate the effects of sputtered particles upon vacuum chamber pressure, the amount of flux leaving the target that returns to the engine, and the time required for the target to become saturated with beam particles. Two different collectors, the solid metallic type and a liquid metal system, are evaluated. The advantages and limitations of each are discussed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1964
- Accession Number
- AD0603905
Entities
People
- A. E. Lennert
- J. D. Trolinger
- J. I. Shipp
Organizations
- Arnold Engineering Development Complex