Dependence of the flare stream velocity on magnetic field orientation

Abstract

The main parameters of a flare stream -its velocity, magnetic field intensity, plasma density, and temperature -are shown to depend on the mutual orientation of magnetic fields in the main body of the stream and within its compressed solar wind region. In particular, the plasma velocity and frozen-in magnetic-field intensity within the main body of the stream, as well as the plasma density and temperature, and the magnetic field intensity within the compressed solar wind region, are maximum when the magnetic fields in the two regions are antiparallel to each other, and minimum when the fields are parallel.The mutual orientation also affects the characteristics of the flares and, in particular, the probability of solar type IV radio emission.The results obtained are explained within the framework of a model that takes into account magnetic field reconnection at the front surface of the stream body.

Analysis of supersubstorm events with reference to polar cap potential and polar cap index

“…They are disturbance associated with auroral activations [Akasofu, 1964;Rostoker, 1971]. The depth knowledge [Bonnevier et al, 1970] of the magnetospheric disturbance [Pudovkin et al, 1985;Kawasaki et al, 1971;Kamide et al, 1999] DP2 is crucial in exploring the substorm phenomena, which is measured by polar cap (PC) index due to ionospheric and field-aligned currents [Tsurutani and Gonzalez, 1987;Tsurutani et al, 2004].…”