Accession Number : AD0450465

Title :   RADIO-STAR SCINTILLATIONS FROM IONOSPHERIC WAVES,

Corporate Author : HIGH ALTITUDE OBSERVATORY BOULDER CO

Personal Author(s) : Warwick, James W.

Report Date : 08 AUG 1963

Pagination or Media Count : 11

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)

Descriptors :   (*STARS, RADIO ASTRONOMY), (*ELECTRON DENSITY, IONOSPHERE), BROADBAND, WAVE PROPAGATION, EXTRATERRESTRIAL RADIO WAVES, ASTROPHYSICS, PROPAGATION, INTERFEROMETERS, MEASUREMENT, RADIOFREQUENCY, REFRACTION.

Distribution Statement : APPROVED FOR PUBLIC RELEASE