Articles | Volume 33, issue 1
Ann. Geophys., 33, 63–74, 2015
Ann. Geophys., 33, 63–74, 2015

Regular paper 15 Jan 2015

Regular paper | 15 Jan 2015

Dipolarization fronts in the near-Earth space and substorm dynamics

I. I. Vogiatzis1,2, A. Isavnin3, Q.-G. Zong2, E. T. Sarris1, S. W. Lu2, and A. M. Tian4 I. I. Vogiatzis et al.
  • 1Department of Electrical and Computer Engineering, Democritus University of Thrace, Xanthi, Greece
  • 2Institute of Space Physics and Applied Technology, Peking University, Beijing, China
  • 3Department of Physics, University of Helsinki, P.O. Box 64, 00014, Finland
  • 4School of Space Science and Physics, Shandong University, Weihai, China

Abstract. During magnetospheric substorms and plasma transport in the Earth's magnetotail various magnetic structures can be detected. Dipolarization fronts and flux ropes are the most prominent structures characteristic for substorm dynamics. However, they are treated as separate magnetotail features independent of each other. In this paper, we analyze a number of dipolarization fronts observed by the THEMIS (Time History of Events and Macroscale Interactions during Substorms) spacecraft at different geocentric distances by applying the magnetohydrostatic Grad–Shafranov (GS) reconstruction technique. Our analysis shows that there is a possibility of dipolarization fronts to originate from highly dissipated flux ropes which are in the late stage of their evolution, subjected to a continuous magnetic deterioration due to the reconnection process. These results may improve our understanding of magnetoplasma processes in Earth's magnetotail.

Short summary
Magnetospheric substorms are one of the most important phenomena occurring in planetary magnetotails, dynamically reconfiguring the near- planet space environment. They encompass various fundamental processes of plasma acceleration and transport in the magnetosphere/ionosphere. The key features of the paper are a new magnetospheric substorm model, a new explanation about the origin of dipolarization fronts (DFs), and a new explanation for energetic ion acceleration/injection in front of DFs.