Accession Number : AD0659479

Title :   OBSERVATIONS OF VLF HISS AT VERY LOW L VALUES.

Descriptive Note : Progress rept.,

Corporate Author : IOWA UNIV IOWA CITY DEPT OF PHYSICS AND ASTRONOMY

Personal Author(s) : Gurnett,Donald A.

Report Date : AUG 1967

Pagination or Media Count : 28

Abstract : Observations of intense bursts of very-low-frequency (VLF) radio noise at low altitudes near the magnetic equator are reported using data from the Injun 3 satellite. The spectral characteristics of these radio noise events typically consist of hiss extending from about 1 kHz to above 8.8 kHz (the highest frequency measured). These equatorial VLF hiss events are very similar to VLF hiss commonly found near the auroral zone. During the ten month lifetime of Injun 3, a total of ten VLF hiss events occurred below 35 degrees magnetic latitude with noise spectral densities exceeding 3 x 10 to the 10th power gamma squared/Hz. All of these events occurred below 350 km altitude and at L values less than 1.2. Nine of the events occurred below 20 degrees magnetic latitude. These equatorial VLF hiss events are noteworthy because of their unusual region of occurrence. Whereas auroral zone VLF hiss may be attributable to the precipitation of energetic (E = or < 10 keV) charged particles, no comparable flux of charged particles is known to exist in the region where the equatorial VLF hiss occurs. (Author)

Descriptors :   (*NOISE(RADIO), *IONOSPHERIC DISTURBANCES), SCIENTIFIC SATELLITES, ULTRALOW FREQUENCY, VERY LOW FREQUENCY, CHARGED PARTICLES, AURORAE, GEOMAGNETISM, WHISTLERS, STABILITY

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE