Satellite and ground-based measurements of the SAP-arc phenomena

Citation
Vv. Afonin et al., Satellite and ground-based measurements of the SAP-arc phenomena, PHYS CH P C, 25(1-2), 2000, pp. 63-66
Citations number
20
Categorie Soggetti
Earth Sciences
Journal title
PHYSICS AND CHEMISTRY OF THE EARTH PART C-SOLAR-TERRESTIAL AND PLANETARY SCIENCE
ISSN journal
14641917 → ACNP
Volume
25
Issue
1-2
Year of publication
2000
Pages
63 - 66
Database
ISI
SICI code
1464-1917(2000)25:1-2<63:SAGMOT>2.0.ZU;2-E
Abstract
Data of the Intercosmos 24 (IC 24) satellite and the ground-based complex o ptical and ionospheric measurements in the region of the stable auroral red (SAR)-arc are presented. Photometric observations were carried out at the Maimaga station (invariant latitude Lambda =56.5 degrees, geomagnetic longi tude lambda(m)=200 degrees) and vertical incidence ionospheric soundings we re made at Yakutsk (Lambda =55.6 degrees, lambda(m)=200 degrees) and Zhigan sk (Lambda=60.4 degrees: lambda(m)=195 degrees) stations. It is shown that when SAR-arc arises for the interval similar to 15 min, the local minimum o f the F-region electron density is formed, and in the ionograms typical sig natures of the polarization jet or SAID are observed. Simultaneously, the h eight of the regular F2 layer increases. This evidences that strong electri c field (E similar to 100 mV/m) exists at the F2 layer heights. In this cas e, in addition to the SAR-arc energy sources, the effect of the ion-frictio nal heating is turned out to be important. Simultaneous measurements aboard the IC-24 satellite at the altitudes similar to 500 km above the SAR-arc a lso show 3 divided by 5 times decreased electron density. The electron temp erature elevates up to similar to 4500 K. At altitudes of 2400 km the ion d ensity increases by 30 - 40 % and T-e rises up to 6300 K. (C) 1999 Elsevier Science Ltd. All rights reserved.