A statistical study of electron acceleration behind the dipolarization fronts in the magnetotail

摘要

[1] We investigate the electron acceleration behind dipolarization fronts (DFs) in the magnetotail from -25 RE to -10 RE through the examination of the energetic electron energy flux (>30 keV) with the observations from Time History of Events and Macroscale Interactions during Substorms (THEMIS). Statistical results of 133 DF events are presented based on the data set from January to April of the years 2008 and 2009. As the DFs propagate earthward, the acceleration of energetic electrons behind the DFs is found to take place over several RE along the tail. The increase in energetic electron energy flux can reach 2–4 orders of magnitude. The dominant accelerationmechanisms are different in the midtail (XGSM ≤-15 RE) and the near-Earth region (-15