Probing 3D Kinematics of CMEs using multi-viewpoint observations
Date & Time :
Zoom meeting space
Coronal mass ejections (CMEs) are enormous eruptions of magnetized plasma from the Sun into interplanetary space with a wide range of kinematic properties. CMEs are generally observed in white-light images by space-based coronagraphs. A single vantage point observation of these features provides us with a two-dimensional representation of the three-dimensional CME structure projected in the plane of the sky. Consequently, the measured quantities such as angular width, height, etc., are also projected on this plane and, therefore, represent lower limits of the true, unprojected CME properties. Hence, a stereoscopy study is essential to derive the true parameters. Thus, in this study, we investigate the true nature of CMEs to understand the differences in the projected and unprojected parameters with significant statistics of multi-viewpoint observations from coronagraphs onboard STEREO and SoHO space observatories. This study focuses on how the kinematics of CMEs in STEREO/COR1 and STEREO/COR2 fields of view vary when observed from inner to outer corona. CMEs are segregated based on their source regions to study their Speed-Width relationships. Speed and width distributions of CMEs obtained from single and multi-viewpoints are compared to understand the true propagation of CMEs in the corona. We have found an empirical relationship between true speed and projected speed of the CME, which can be used as a quick tool in the upcoming Aditya-L1 mission to find the true speed once the projected speed is known.
About Speaker :
Harshita Gandhi was a project student under Prof. Dipankar Banerjee