Author:
Yago K.,Shiokawa K.,Yumoto K.,Baishev D. G.,Solovyev S. I.,Rich F. J.
Abstract
Abstract
Auroral particles, field-aligned currents, and plasma convections in the vicinity of the brightening arc at substorm onset are still not well understood, since it is very rare to have conjugate satellite measurements above the brightening arc. In this paper, we investigate the characteristics of auroral particles and fields associated with the brightening arc at a pseudo-onset of substorm on October 31, 2000, using ground all-sky TV images, IMAGE FUV auroral images, and particle, magnetic field, and plasma flow data obtained by the DMSP F12 satellite. The arc brightening at Tixie (66.0°MLAT), Russia, occurred at 1004 UT (18.75 MLT) coincident with a coherent Pi 2 pulsation at midlatitudes and with the DMSP crossing above the arc. The brightening arc did not develop on a global scale, indicating that this event is a pseudo auroral breakup, which occurred ≈16 min before the major substorm expansion onset. IMAGE auroral images indicate that the longitude of the brightening center was ≈2.5 h nightside of Tixie. The DMSP data show that the precipitating particles associated with the brightening arc correspond to an electron inverted-V structure at the equatorward edge of the electron precipitation region. The arc was located in the energetic (>1 keV) ion precipitation region, near the equatorward boundary of the upward region 1 field-aligned current, and at the peak of the sunward convection velocity. These facts indicate that the brightening arc at duskside of the onset local time was located in the inner plasma sheet at the inner edge of the region 1 current source in the sunward convection region.
Publisher
Springer Science and Business Media LLC
Subject
Space and Planetary Science,Geology
Cited by
6 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献