On transpolar arc formation correlated with solar wind entry at high latitude magnetosphere

Monday, 15 December 2014
Bagrat G Mailyan1,2, Quanqi Shi3, Romain Maggiolo4, Qiugang Zong5, Suiyan Fu5, Yongliang Zhang6, Zhonghua Yao7 and WeiJie Sun5, (1)Shandong University at Weihai, Weihai, Shandong, China, (2)Alikhanian National Laboratory, Yerevan, Armenia, (3)Shandong University at Weihai, Weihai, China, (4)Belgian Institute for Space Aeronomy, Brussels, Belgium, (5)Peking University, Beijing, China, (6)The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, United States, (7)University College London, London, United Kingdom
Recently, Cluster observations revealed the existence of new regions of solar wind plasma entry at the high latitudes of the Earth’s magnetosphere, at the lobes tailward of the cusp region, mostly during periods of northward IMF. Such periods of northward IMF are associated with the presence of transpolar arcs. Observations from Global Ultraviolet Imager (GUVI) instrument onboard TIMED spacecraft are used to investigate a possible link between solar wind entry in the high latitude magnetosphere and the formation of transpolar arcs. Data from IMAGE and DMSP spacecraft are also used to investigate the time evolution and particle characteristics of the transpolar arc.
We present a case study of a theta aurora correlated with the solar wind entry. The observations show a simultaneous occurrence of aurora activity at the magnetotail and high latitudes, suggesting two-part structure of the apparent continuous band of the transpolar arc.