DECAY OF ELECTRON DENSITY IN THE WAKES OF HYPERVELOCITY SPHERES
Abstract
The electron line density in the wakes of hypervelocity aluminum and copper spheres traveling 18,000 to 21,000 feet per second was measured as a function of time, by means of a transmission resonant cavity. The ambient pressure was varied over the range of 10 to 160 torrs to determine its influence on the electron density decay. Typical results are given for measurements of the electron density in air and in nitrogen. A significant electron density was found to persist in nitrogen trails for long times, because the electron-ion recombination reaction is the only important electron removal process. In air, electron attachment becomes the predominant process for electron decay, after an initial period when electron-ion recombination controls the decay. Results on the effect of ablated aluminum and sabot material on the electron density decay are given. Electron decay data which can be repeated from shot to shot, without large discrepancies, are shown to be obtainable under carefully controlled experimental conditions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 23, 1964
- Accession Number
- AD0612152
Entities
People
- W. M. Kornegay
Organizations
- Massachusetts Institute of Technology