Insights from the March 13, 2012, event with 110° longitudinal separation: Propagation and flux rope orientation

A very fast, broad, and inclined Coronal Mass Ejection (CME) occurred on March 13, 2012, and it was surrounded by three coronal holes. The particular configuration of the event induced that two days later, the interplanetary counterpart of the CME was captured by Earth-surrounding spacecraft and STEREO-A, which at that moment were separated 110° in longitude. In this proceeding, the propagation and magnetic topology of the CME is analysed by utilising the OSPREI propagation model and Hidalgo’s analytical flux rope (FR) model respectively. This research complements previous findings provided in Carcaboso et al. (2024). The study reveals that the complexity of this event is such that, with the current version of the OSPREI model, we cannot fully explain the CME’s dynamics. Magnetic topology analysis with Hidalgo’s model indicates the CME had a FR orientation of approximately 30 degrees with respect to the ecliptic plane at 1 au, with Earth encountering a quasi-frontal FR and STEREO-A a flank crossing. The findings underscore the complexity of CME propagation and the importance of advanced modelling techniques in understanding CME propagation and topology.