Recent studies in micropulsation theory

  title={Recent studies in micropulsation theory},
  author={David J. Southwood},
  journal={Space Science Reviews},
  • D. Southwood
  • Published 1 September 1974
  • Physics
  • Space Science Reviews
Three recent studies in the theory of micropulsations are described. Attention is given to the behaviour of the signal below the magnetosphere in the ionosphere and atmosphere, to the field line resonance problem and to hot plasma effects on magnetospheric hydromagnetic waves. In each case recent relevant observations are discussed. 

Comments on Field Line Resonances and Micropulsations

Summary Features and limitations of a simple plasma model exhibiting hydro-magnetic transverse mode field line resonances are discussed in relation to geomagnetic micropulsations.

Dispersion relation for magnetosonic waves within the upper atmospheric plasma

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Problems of the physics of geoelectromagnetic waves (a review)

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Effect of atmosphere and ionosphere on magnetospheric micropulsation signals

THE large-scale structure of low frequency hydromagnetic waves in the magnetospheric plasma can be understood from observations of micropulsations at the Earth's surface. Signals have to penetrate

The Effect of Two Periodic Conductivity Anomalies on Geomagnetic Micropulsation Measurements

Summary The effect of induced magnetic fields on the Earth based measurement of micropulsations is examined by means of two simple two-dimensional models, one with six and the other four variable

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The amplitude and phase changes of the magnetic-field component normal to the strike of a geoelectric inhomogeneity are computed. The effects of the geoelectric inhomogeneity on the polarization

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A new theory of the mirror instability is developed which includes the effects of ∇B and ∇n, finite Larmor radius, and a coexisting cold plasma. It is shown that the instability becomes overstable

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The behaviour of continuous pulsations pc 2–5 observed on the ground has been known for some time, and almost circularly polarised waves are predicted confirming an earlier heuristic suggestion.

Resonant vibration of the magnetosphere observed from Explorer 26

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A theory of long period magnetic pulsations 1

A theory of long-period (Pc 3 to Pc 5) magnetic pulsations is presented based on the idea of a steady state oscillation of a resonant local field line that is excited by a monochromatic surface wave

Latitude‐dependent characteristics of long‐period geomagnetic micropulsations

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Transverse, low-frequency oscillations in the magnetic field have been recorded in the equatorial plane at 6.6 RE (earth radii) with the UCLA magnetometer on board ATS 1. The oscillations have