RADIO-STAR SCINTILLATIONS FROM IONOSPHERIC WAVES,

Abstract

A swept-frequency interferometer operating in the frequency range from 7.6 to 41 megacycles per second records positions and durations of Cassiopeia A scintillations. Besides demonstrating the broad bandwidth characteristic of scintillations in this frequency range, the interferometer ofter reveals systematic trends in the duration and the position of the radio star as functions of frequency. On several occasions, the effects can be interpreted simply and directly in terms of wavelike irregularity structure at about 200 kilometers elevation. In one instance studied in detail, the wavelength was 17 kilometers from crest to crest and the phase velocity of the order of 60 meters per second. From a statistical argument the conclusion is drawn that most of the irregularities producing scintillations recorded by us are in motion towards the south. The absence of duration and angle-of-arrival effects from many other broadband scintillations implies the existence of a finer structure, superposed on the basic long-wavelength pattern. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 08, 1963
Accession Number
AD0450465

Entities

People

  • James W. Warwick

Organizations

  • High Altitude Observatory

Tags

DTIC Thesaurus Topics

  • Angle Of Arrival
  • Bandwidth
  • Broadband
  • Elevation
  • Frequency
  • Frequency Bands
  • Interferometers
  • Long Wavelengths
  • Phase Velocity
  • Scintillation

Fields of Study

  • Physics

Readers

  • Astronomy and Astrophysics.
  • Space/Atmospheric Physics.
  • Theoretical Analysis.