Authors: Amaal Mohamed (Solar Lab., Solar and Space Dept., “NRIAG”, Helwan, Cairo, Egypt, 11421.)

The interaction dynamics between coronal holes (CHs) and coronal mass ejections (CMEs) significantly impact space weather and plasma physics. Depending on their relative positions, CHs can either deflect a CME away from or towards the Sun-Earth line (Gopalswamy et al., 2009). This interaction is quantified by the coronal-hole influence parameter (CHIP), which considers factors such as CH area, distance from the eruption site, and photospheric magnetic field strength within the CH.
This study presents the first direct observation of CME deflection during the February 15, 2011 event associated with an X2.2 flare (S21W21) at 01:44 UT, observed by STEREO/COR1 and COR2. The computed CHIP for this event is 0.73 G, resulting in a deflection angle of 62◦. CH identification was conducted using Solar Dynamics Observatory (SDO) AIA 193  ̊A images, with SDO/HMI used to measure magnetic field strength within the largest CH (centroid at S59W15), located near the CME eruption site (S21W21). STEREO/COR2 images confirmed a deflection angle of 38◦, consistent with CH observations.
Additionally, the study investigates the existence of a Flux Rope (FR) by analyzing its topology in the corona through Non-linear Force Free Field (NLFFF) extrapolation. Application of the NLFFF model to active region 11158 on February 15, 2011 confirmed the presence of a flux rope.