The large-scale magnetospheric electric field observed by Double Star TC-1

• Published in: Annales geophysicae (1988) 2010-09, Vol.28 (9), p.1625-1631
• Main Authors: HE, Z. H, LIU, Z. X, CHEN, T, SHEN, C, LI, X, CARR, C, REME, H
• Format: Article
• Language: English
• Subjects: Astronomy; Earth, ocean, space; Electric fields; Exact sciences and technology; External geophysics; Physics of the ionosphere; Physics of the magnetosphere
• ISSN: 0992-7689; 1432-0576; 1432-0576
• DOI: 10.5194/angeo-28-1625-2010

The relationship between the average structure of the inner magnetospheric large-scale electric field and geomagnetic activity levels has been investigated by Double Star TC-1 data for radial distances ρ between 4.5 RE and 12.5 RE and MLT between 18:00 h and 06:00 h from July to October in 2004 and 2005. The sunward component of the electric field decreases monotonically as ρ increases and approaches zero as the distance off the Earth is greater than 10 RE. The dawn-dusk component is always duskward. It decreases at about 6 RE where the ring current is typically observed to be the strongest and shows strong asymmetry with respect to the magnetic local time. Surprisingly, the average electric field obtained from TC-1 for low activity is almost comparable to that observed during moderate activity, which is always duskward at the magnetotail (8 RE~12 RE).