Comparison of Alkali Ion Emitters
Abstract
Lithium, Potassium, and Cesium ion sources have been studied using devices based on thermal emission from a Beta Eucryptite structure as possible ion sources for use in satellite charge control. The experiments evaluated the power requirements of the different ion emitters to produce approximately 10 (microamps) of current and tested the effects of using an Osmium Ruthenium coating to increase the work function of the emitter surface. Lifetime tests of the different ion emitters were also performed. Analysis of the experimental findings showed that lithium ion sources with a lifetime of 93 hours and Potassium ion sources with a lifetime of 44 hours produced acceptable current levels for use in spacecraft charge control devices. Potassium sources produced the necessary current, (10 microamps), at 140 (C) lower temperature than the Lithium sources. All of the coated sources produced wildly fluctuating currents at the 10 (microamp) level and were not acceptable for the purpose intended.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1991
- Accession Number
- ADA243105
Entities
People
- Dean A. Gant
Organizations
- Naval Postgraduate School