PROPAGATION OF HYDROMAGNETIC WAVES IN THE LOWER EXOSPHERE AND THE ORIGIN OF SHORT PERIOD GEOMAGNETIC PULSATIONS

Journal Article · Mon Jan 01 04:00:00 EST 1962 · J. Atmospheric Terrest. Phys.

DOI:https://doi.org/10.1016/0021-9169(62)90207-6· OSTI ID:4008966

Jacobs, J A; Watanabe, T

The exospheric region below an altitude of about 2000 km, where the Aifven velocity has a very steep upward gradient, amplifies hydromagnetic waves coming from outer space with certain special periods. The longest characteristic period, corresponding to the fundamental mode, is of the order of from 1 to several seconds, which is comparable to the period of that particular group of geomagnetic micropulsations called pearls. The fundamental period has a frequency-width of the order of 0.02 to 0.08 sec/sup -1/, which is of the right order of the time-scale of fluctuations of the envelope of the pearls. The amplifying ratio also gives the correct order of magnitude of the intensity of pearls as observed at the earth's surface. (auth)

• Research Organization: Univ. of British Columbia, Vancouver, Can.
• NSA Number: NSA-18-021076
• OSTI ID: 4008966
• Journal Information: J. Atmospheric Terrest. Phys., Journal Name: J. Atmospheric Terrest. Phys. Vol. Vol: 24
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

DETECTION
EARTH
EFFICIENCY
FREQUENCY
IONOSPHERE
LEVELS
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
MOTION
OSCILLATIONS
PEARS
PHYSICS
PULSES
SURFACES
VELOCITY