Accession Number : AD0654974

Title :   IPDP EVENTS AND THEIR GENERATION IN THE MAGNETOSPHERE,

Corporate Author : BOEING SCIENTIFIC RESEARCH LABS SEATTLE WASH GEO-ASTRO PHYSICS LAB

Personal Author(s) : Knaflich,H. B. ; Kenney,J. F.

Report Date : MAY 1967

Pagination or Media Count : 22

Abstract : Irregular pulsations of decreasing period are characterized by a broad band of ULF noise that rises in frequency over the duration of the event. IPDP events frequently have structured elements in the noise that have been detected simultaneously at conjugate stations by Gendrin and Troitskaya. Under the assumption that these structured elements have been generated at the equator in the magnetosphere by an impulsive source, the later arrival of the higher frequencies may be interpreted as the results of propagation in a dispersive medium. Methods that have been applied to pc 1 events are applied to the structured elements of IPDP events to locate their origin in the magnetosphere. The dispersion analysis of the structured IPDP elements observed during 1965 and 1966 shows that they are generated in a narrow range of solar magnetospheric longitude centered around 20 hours local time at L values between 6 and 13 earth radii. The broad-band unstructured noise seems to originate in a zone of magnetic turbulence just outside the normal trapping region, so that the structured elements could be the dispersed signal resulting from a broad-band impulse. This could also be evidence for particle injection into the magnetosphere during times of elevated magnetic activity. (Author)

Descriptors :   (*MAGNETOSPHERE, *NOISE(RADIO)), ULTRALOW FREQUENCY, BROADBAND, MAGNETIC FIELDS, RADIO TRANSMISSION, EXTRATERRESTRIAL RADIO WAVES, TURBULENCE, PERIODIC VARIATIONS, GEOMAGNETISM

Subject Categories : Atmospheric Physics
      Geomagnetism
      Radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE