Analysis of Satellite Data on Precipitating Particles in Coordination with ELF Propagation Anomalies.
Abstract
An investigation has been made of the effects of energetic particle precipitation into the atmosphere on the transmission of ELF signals based on coordinated data acquired during the Greenland Sea exercise in 1977, and at other times. In the Greenland Sea exercise significant fluxes of precipitating electrons were measured on many of the satellite passes and unusually high intensities were observed on several occasions, two of which were selected for special study. A search was made for possible correlation between electron precipitation and ELF signal strength, but no evidence was found for a consistent variation between the two parameters. This finding may partly reflect the uncontrolled and variable receiving conditions during the Greenland Sea exercise. For two of the major electron precipitation events observed in the April-May 1977 Greenland Sea exercise, detailed analyses were performed of the electron energy spectra and intensities, and of the resulting energy deposition profiles. For each of the electron density profiles, calculations of the ELF signal strengths were performed with the waveguide-mode computer program developed at the Naval Ocean Systems Center. From these calculations taken together with computations for other events it became clear that the received signal may either increase or decrease, depending upon the spatial extent and location of ionization. The predicted effects of a single relativistic electron precipitation event are not severe, but due to their frequent occurrence they may provide the opportunity to verify experimentally the predicted effects of more severe and rarely occurring phenomena such as solar particle events.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 30, 1978
- Accession Number
- ADA075281
Entities
People
- Edward E. Gaines
- Joseph B. Reagan
- Robert C. Gunton
- Trygve R. Larsen
- William L. Imhof
Organizations
- Lockheed Martin Missiles and Space