Average Observed Properties of Halo CMEs During Solar Cycle 23

E. Mitsakou, X. Moussas

Department of Astrophysics, Astronomy and Mechanics, Faculty of Physics, National University of Athens, Panepistimiopolis, GR15784, Zografos, Athens, Greece

We use a superposed epoch approach, in order to study the average characteristics and behaviour of halo Coronal Mass Ejections during solar cycle 23. We identify the interplanetary signatures of CMEs, during the ascending and descending phase of the solar cycle, using Omniweb solar wind data. We categorize CMEs into groups and find similarities and differences between them, using superposed epoch analyses of the observed interplanetary parameters during 1996-2007, considering as epoch zero time the start time of the CME-driven shock.