The Spatial and Temporal Variations in High Latitude Cosmic Noise Absorption and Their Relation to Luminous Aurora
Abstract
The spatial and temporal variations in cosmic radio noise absorption were investigated at College, Alaska, during 1962-1963 by means of riometers using one narrow beam antenna and two relatively broad beam antennas which were pointed at different directions along the magnetic meridian. The narrow beam antenna had a 12 deg beamwidth and was periodically swung in the magnetic meridian from 12 deg north of zenith to 12 deg south of zenith. Each of the broad beam antennas had a 26 deg beamwidth and was directed to 40 deg from zenith, one to the south and the other to the north. In order to explore the relation of the spatial variations in absorption with the differences in auroral luminosity existing in different directions at a given time, two lambda 5577A photometers were operated in the two switching directions of the narrow beam antenna i.e. 12 deg N and 12 deg S. The information about the auroral coverage of the various antenna beams was obtained from all-sky photographs. A simultaneous study of radio-wave absorption in relation to luminous aurora resulted in the conclusion that the nighttime radio-wave absorption observed at College, Alaska falls into the following two main categories. The absorption belonging to Category I is observed at any time between 2000-0200 hrs, correlates well with the intensity fluctuations of lambda 5577A, and is limited to luminous regions of the sky only. Included in the above category is the absorption associated with the quiet as well as bright and active phases of the display.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1963
- Accession Number
- ADA484068
Entities
People
- H. Leinbach
- R. Parthasarathy
- Z. A. Ansari
Organizations
- University of Alaska Fairbanks