Electron Precipitation Patterns in the Vicinity of a VLF Transmitter.
Abstract
Using high resolution pitch angle measurements made by a magnetic focusing electron spectrometer on the S3-3 satellite, angular distributions of 235 keV electrons precipitated by a ground-based VLF transmitter are compared with the pitch angle distributions that would be produced by various patterns of longitudinal interaction regions. The observed electrons are in the drift loss cone, necessitating the use of a trace-back-to-longitude-of-origin technique coupled with a two-dimensional convolution program describing the response of the electron spectrometer. The data are well-fit with both theoretical calculations of ionospheric field intensity patterns above a transmitter and with a similar pattern of received field intensities measured along a traverse in the conjugate region. The agreement between the data and field patterns implies a linear or quasi-linear wave-particle interaction. The energy-frequency relationship between the electrons and the waves implies an interaction region low on the magnetic field line, perhaps near or at the unperturbed mirror point. Keywords include: Electron precipitation; Magnetospheric electrons; VLF precipitation; and Wave-particle interactions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 15, 1985
- Accession Number
- ADA163716
Entities
People
- Alfred L. Vampola
Organizations
- The Aerospace Corporation