The relationship between pi2's observed at midlatitudes and at geosynchronous orbit. Final report, 15 December 1979-30 November 1980

Technical Report · Wed Jan 07 04:00:00 EST 1981

OSTI ID:5866746

Hughes, W J; Singer, H J

We have completed a study of substorm associated pi2 magnetic pulsations using data from the AFGL magnetometer network. A global study, using 40 ground stations and three spacecraft, of a few selected events demonstrates the global nature of the pi2 signature and suggests that day and nightside wave activity is sometimes closely related. Propagation delay times of the signal over many hours of local time were found to be immeasurably small (< 30s) at midlatitudes (L about 3). A correlation of a month's data from two geostationary spacecraft (GOES 2 and GOES3) with the AFGL magnetometer data shows that pi2 signals are more localized azimuthally in space at geostationary orbit, than they are on the ground at midlatitudes, where they usually extend further than the 4 hours local time span of the AFGL network. We also found that during quiet times (low K sub p) pi2's occur less often at geostationary orbit than on the ground. This is probably the result of the spacecraft being further from the plasma-sheet, the probable pi2 source region, at quiet times. We conclude that pi2's are a promising tool with which to globally monitor substorm activity using a few midlatitude stations.

• Research Organization: Boston Univ., MA (USA). Dept. of Astronomy
• OSTI ID: 5866746
• Report Number(s): AD-A-098938/4
• Country of Publication: United States
• Language: English

Related Subjects

640203* -- Atmospheric Physics-- Magnetospheric Phenomena-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
EARTH ATMOSPHERE
MAGNETIC STORMS
MAGNETOMETERS
MAGNETOSPHERE
MEASURING INSTRUMENTS
MONITORING
PULSATIONS