Masahisa Sugiura

TL;DR: Auroral electrojet index and universal time variations, discussing polar disturbance statistics are discussed in this paper, where the authors also discuss the effect of time variations on polar disturbances and their correlation.

TL;DR: In this paper, the existence of a sharp break in the power spectrum of AE at about 5 hours is demonstrated and several possible explanations of the nonlinear response of AE to the IMF Bs driver are briefly discussed, including variable ionospheric conductivity (increasing with Bs) and several AE saturation mechanisms for the low frequency regime.

TL;DR: In this paper, a model for sudden commencements of magnetic storms observed during the IGY is presented, where the impact of the solar gas stream upon the geomagnetic field creates a shock wave, which propagates to the earth as a longitudinal hydromagnetic wave in low latitudes.

TL;DR: In this paper, a detailed study of simultaneous density and electric field fluctuation spectra over a large-scale length range seen in association with large structured convective plasma flows, field-aligned currents, and particle precipitation at high latitudes is presented.

TL;DR: In this article, the symmetry relations in the magnetic perturbation at a pair of conjugate points due to oscillation of the lines of force of the geomagnetic field are studied.