Secondary Electron Generation, Emission and Transport: Effects on Spacecraft Charging and NASCAP Models
Abstract
Secondary electron phenomena play an important role in many aspects of spacecraft charging. This paper discusses three distinct cases that show: 1)A good formulation for the secondary electron yield as a function of incident electron energy is needed in order to determine whether a given particle spectrum will cause strong negative charging for a given spacecraft material; 2) Suppression of secondary electron emission by electric fields plays a dominant role in sunlight charging; and 3) Surface conductivity associated with the presence of a secondary electron layer plays a key role in enhancing the current collection by small, positively biased pinholes or interconnects. The treatments of these various aspects of secondary electron phenomena in the NASCAP and NASCAP/LEO codes provide good quantitative results for secondary electron effects. Errors are probably due to uncertainties in the input parameters to the codes and to uncertainties in experimental measurements than to inadequacies in the code formulations.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1987
- Accession Number
- ADP005703
Entities
People
- Carolyn Purvis
- Ira Katz
- James C. Roche
- Myron Mandell