THEORY OF IRREGULAR MAGNETIC MICROPULSATIONS ASSOCIATED WITH A MAGNETIC BAY

Journal Article · Sun Mar 01 04:00:00 EST 1964 · Journal of Geophysical Research (U.S.)

DOI:https://doi.org/10.1029/JZ069i005p00947· OSTI ID:4074468

Nishida, A

A burst of irregular pulsations (period, approximately 0.2 to 200 sec) in the auroral zone, which appears at the onset of a sharp negative bay accompanied by various phenomena testifying the intrusion of a high-speed electron beam from above, is explained by the hydromagnetic instability. It is shown that the presence of a passing electron beam modifies the character of a hydromagnetic wave in the magnetosphere in such a way that the instability is able to take place. With adequately chosen parameters of the beam and the ambient plasma, the range of the period of growing waves generated in the magnetosphere is estimated, and a close agreement is found with that of a pulsation burst. Irregular pulsations in the lower latitudes, which are observed in coincidence with the pulsation burst in the auroral zone, may be due to the oblique propagation of these growing waves and the leakage of the screening current, which flows in the auroral zone when the pulsation burst is taking place. (auth)

• Research Organization: Univ. of Chicago
• Sponsoring Organization: USDOE
• NSA Number: NSA-18-015023
• OSTI ID: 4074468
• Journal Information: Journal of Geophysical Research (U.S.), Journal Name: Journal of Geophysical Research (U.S.) Vol. Vol: 69; ISSN JGREA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

AURORAE
COSMIC RADIATION
CURRENTS
EARTH
ELECTRON BEAMS
IONOSPHERE
LOSSES
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
MOTION
OSCILLATIONS
PHYSICS
PLASMA
PULSES
STABILITY