The Interaction of Three Coronal Mass Ejections Observed on 2012 March 5 from Multiple Viewpoints
Abstract
We examined three CMEs that were observed together on 2012 March 5 in the corona at heights less than 20 Rsun. We analyzed observations from three viewpoints: Earth, STEREO-A and STEREO-B to reconstruct their three-dimensional (3D) geometry and kinematics and determine their interaction. The observations combined with our analysis show an initial slow raising CME (CME-1) that originated from a prominence eruption near the center of the solar disk as viewed from Earth. A second CME (CME-2) then erupts from an active region (AR) near the NE limb. These two CMEs are present in the corona not interacting when a third CME (CME-3) erupts from the same AR as CME-2. CME-3 is extremely impulsive and drives a shock that is observed as a halo from the all viewpoints. We find that the shock driven by CME-3 passed through CME-1 with no observable change in the geometry, trajectory, or velocity of CME-1. A possible signature of CME-1 in situ indicates that the plasma inside the flux rope was heated by the passage of the shock. CME-2 is accelerated by CME-3 to more than twice its initial velocity yet remains a separate structure ahead of the CME-3 front. CME-2 is deflect by CME-3 24 deg northward for a total deflection of 40 deg north of its SR. CME-3 interacts with both CME-1 and CME-2 with very different results due to the locations of their magnetic structures. CME-CME interactions such as these could have profound effects on the Earth-impact of such CMEs.
- Publication:
-
Solar Heliospheric and INterplanetary Environment (SHINE 2015)
- Pub Date:
- July 2015
- Bibcode:
- 2015shin.confE.162C