Articles | Volume 33, issue 9
Ann. Geophys., 33, 1173–1181, 2015

Special issue: Dynamic processes in geospace

Ann. Geophys., 33, 1173–1181, 2015

Regular paper 25 Sep 2015

Regular paper | 25 Sep 2015

Combined effects of concurrent Pc5 and chorus waves on relativistic electron dynamics

C. Katsavrias1,2, I. A. Daglis1, W. Li3, S. Dimitrakoudis4, M. Georgiou1, D. L. Turner5, and C. Papadimitriou1 C. Katsavrias et al.
  • 1Department of Physics, National and Kapodistrian University of Athens, Athens, Greece
  • 2Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
  • 3Department of Atmospheric and Oceanic Sciences, UCLA, California, USA
  • 4Institute for Astronomy, Astrophysics, Space Applications & Remote Sensing, National Observatory of Athens, Penteli, Greece
  • 5The Aerospace Corporation, El Segundo, California, USA

Abstract. We present electron phase space density (PSD) calculations as well as concurrent Pc5 and chorus wave activity observations during two intense geomagnetic storms caused by interplanetary coronal mass ejections (ICMEs) resulting in contradicting net effect. We show that, during the 17 March 2013 storm, the coincident observation of chorus and relativistic electron enhancements suggests that the prolonged chorus wave activity seems to be responsible for the enhancement of the electron population in the outer radiation belt even in the presence of pronounced outward diffusion. On the other hand, the significant depletion of electrons, during the 12 September 2014 storm, coincides with long-lasting outward diffusion driven by the continuous enhanced Pc5 activity since chorus wave activity was limited both in space and time.