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Geomagnetic micropulsation measurements for magnetosphere and solar wind diagnostics
Geomagnetic micropulsations mechanism, discussing hydromagnetic waves transmission generated by interface instability between solar wind and magnetosphere, noting transmission path role
Geomagnetic micropulsation theory, discussing mechanisms responsible for amplitude spectrum at earth surface and power spectral density
Source mechanisms responsible for generating geomagnetic micropulsations
Steady geomagnetic micropulsations and solar corpuscular streams
Geographical distributions of geomagnetic micropulsations continuously recorded on frequency modulated magnetic tape
Energetic electron precipitation and geomagnetic micropulsations related to auroral substorms from balloon X ray and ground based data
Energetic electron precipitation and 5 to 40 second geomagnetic micropulsations relation to auroral substorms
The observed close correlation between the plasmapause and micropulsations is explained on the basis of a universal instability model. Both theoretical and experimental studies of a nonhomogeneous magnetoplasma indicate that a steep plasma density gradient at the plasmapause is likely the origin of the universal instability in the magnetosphere. Drift waves excited at the plasmapause may be unstable in the direction of the electron drift and propagate eastward nearly perpendicularly to the magnetic field. The drift waves, however, tend to convert very quickly to ion sound or Alfven waves with a much larger phase velocity parallel to the magnetic field. This may be a possible source mechanism for rather regular geomagnetic micropulsations, and specific mechanisms are identified for the long- and short-period cases.
Geomagnetic micropulsation nature related to distribution of Alfven velocity in magnetosphere
Auroral substorm magnetospheric effects, noting energetic electron precipitation and geomagnetic micropulsations
Temporal characteristics of geomagnetic micropulsations and related energetic auroral zone electron precipitation as function of local time
Using a set of 112 magnetopause locations selected from those obtained in recent years with the aid of Imp satellites on the dayside of the magnetosphere over 0600-1800 LT, extended results are presented on the problem of geomagnetic micropulsation periods in relation to magnetospheric parameters. These results include the finding that the two groups represented by micropulsation period ranges from 20 to 40 sec and from 40 to 80 sec, respectively, have a completely different dependence on the radial distance of the magnetopause from satellite experiments.
Forbush decreases and development of geomagnetic storm fields
It is shown that the observed local time variation of dayside geomagnetic micropulsations is consistent with the Kelvin-Helmholtz generation mechanism operating at the magnetopause. The variation of the angle between the interplanetary magnetic field and the magnetopause around the magnetosphere causes variations in the magnetosheath magnetic field, which in turn lead to local time variations in micropulsation amplitudes. Morning sector pulsations are expected to be larger than afternoon sector pulsations. Furthermore, large-amplitude pulsations are expected to be more frequently observed when the angle between the interplanetary magnetic field and the solar wind velocity in front of the bow shock is small.
Concept of auroral magnetospheric substorm and relation to electron precipitation and micropulsations
Characteristics of pearl micropulsations in auroral zone and relation to electron precipitation
Satellite drag analysis of atmospheric temperatures noting effects of UV, solar radiation and geomagnetic fluctuations