Observations of narrow microburst trains in the geomagnetic storm of August 4-6, 1972

Journal Article · Sun Apr 01 04:00:00 EST 1973 · J. Geophys. Res., v. 78, no. 10, pp. 1727-1729

DOI:https://doi.org/10.1029/JA078i010p01727· OSTI ID:4432418

Brown, R R

In the intense geomagnetic disturbances of early August 1972, auroral zone microburst trains were observed at balloon altitude and found to be significantly narrower in burst width and spacing than microbursts found previously at the same site. These observations suggest that the spacing of microburst peaks, as well as their width, is related to variations in the power spectrum of a magnetospheric acceleration process rather than the bounce motions of electrons in the geomagnetic field or the modulation of electron precipitation by drift waves in magnetospheric plasma. In the geomagnetic activity that followed the solar flares in early August 1972, intense fluxes of auroral x rays were encountered during balloon flights launched from College, Alaska. Although much of the time variations of the x-ray fluxes observed during these flights represented known features of electron precipitation at auroral latitudes, one new and distinct feature was evident. In particular, it was found that the widths and spacings of auroral zone microbursts (Anderson and Milton, 1964) on this occasion were significantly smaller than those observed previously on many balloon flights from the same site. Thus, instead of microburst trains with widths at half-intensity points of ~0.2 sec and spacings of ~0.6 sec, the majority of the microbursts encountered on two flights from College had widths of ~0.1 sec and spacings of ~0.4 sec. (auth)

• Research Organization: Department of Physics, University of California, Berkeley, California, 94720
• Sponsoring Organization: USDOE
• NSA Number: NSA-29-001310
• OSTI ID: 4432418
• Journal Information: J. Geophys. Res., v. 78, no. 10, pp. 1727-1729, Journal Name: J. Geophys. Res., v. 78, no. 10, pp. 1727-1729; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

*AURORAE-- ELECTRON PRECIPITATION
*MAGNETIC STORMS-- X RADIATION
GEOMAGNETIC FIELD
N58100* --Physics (Atmospheric)--Auroral & Ionospheric Phenomena
SOLAR FLARES