Analysis of Large Deflections of Prominence–CME Events during the Rising Phase of Solar Cycle 24

Maria Valeria Sieyra - UTN-FRM, CONICET; Mariana Cécere - IATE, CONICET-UNC, Argentina; Hebe Cremades - UTN-FRM, CONICET, Argentina; Francisco Iglesias - UTN-FRM, CONICET, Argentina; Abril Sahade - IATE, CONICET-UNC, Argentina; Marilena Mierla - STCE-SIDC, ROB, Belgium; Andrea Costa - IATE, CONICET-UNC, Argentina; Matthew West - STCE-SIDC, ROB, Belgium; Elke D'Huys - STCE-SIDC, ROB, Belgium

Session: The solar sources of space weather

Abstract

The analysis of the deflection of coronal mass ejections (CMEs) plays an important role in the improvement of forecasting their geo-effectiveness. Focusing on the governing conditions that drive deflections during the early stages, we performed an extensive analysis of 13 CME events that exhibited large deflections in the low corona. The study was carried out using solar corona imaging observations at different heights and wavelengths, namely the Project for Onboard Autonomy 2 (PROBA2), Solar Dynamics Observatory (SDO), Solar TErrestrial Relations Observatory (STEREO), Solar and Heliospheric Observatory (SOHO) spacecraft, and the National Solar Observatory (NSO). The selected events were observed between October 2010 and September 2011, taking advantage of the quadrature location of the STEREO spacecraft and Earth. We determined the 3D trajectory of the front envelope of the CMEs and their associated prominences by means of a forward-modeling and tie-pointing tool, respectively. Using a potential-field source-surface model, we estimated the magnetic-energy distribution of the ambient medium to investigate its role in the non-radial propagation of both structures and in their kinematic properties. The ambient magnetic environment during the early stages is found to be crucial in determining the trajectory of the CME events, in agreement with previous reports.