FARADAY ROTATION MEASUREMENTS OF ELECTRON CONTENT NEAR THE MAGNETIC EQUATOR, USING THE TRANSIT IV-A SATELLITE.
Abstract
At the Electronics Laboratory of the Military Research and Development Center, Bangkok, Thailand, Faraday rotation observations of the 54-MHz signal from the Transit IV-A (1961 Omicron I) satellite were made during ten monthsof a sunspot minimum period (1964). In this report, two methods of analysis-involving rotation rate and total number of rotations--are applied to the Bangkok observations. The rotation-rate method is used to determine the electron content when the angle between the ray path and the geomagnetic field is 90 deg (transverse position). The total-rotations method is used to determine latitudinal variations of the electron content of the equatorial ionosphere for five selected satellite passes from a joint analysis of observations at three stations, Singapore, Bangkok, and Hong Kong. The diurnal variation of the local electron content shows low early-morning values and high afternoon values, resulting in a large maximum-to-minimum ratio. Mean scale height is developed from the equivalent slab thickness and compared with results from other sources. The equatorial variation of electron content shows clearly the equatorial trough anomaly. A Chapman model ionosphere is used to compare a calculated electron content with the measurements and to illustrate the F-layer critical frequency variation as a continuous function of latitude. From the joint analysis, data were obtained for latitudes extending continuously from Indonesia well up into China for longitudes near 105 F. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1966
- Accession Number
- AD0486729
Entities
People
- Clifford L. Ruffenach
- Robert E. Leo
- Vichai T. Nimit
Organizations
- SRI International