Numerical and observational study of stealth and consecutive coronal mass ejections

When (times in MT)
Wed, Dec 7 2022, 11am - 1 hour
Event Type
Dana Talpeanu
Royal Observatory of Belgium
Building & Room

Photospheric shearing motions play an important role in the initiation of coronal mass ejections (CMEs). Even so, there are events for which the source signatures are difficult to locate, while the CMEs can be clearly observed in coronagraph data. These events are therefore called ‘stealth’ CMEs. In this work, we numerically simulated consecutive CMEs by imposing shearing motions onto the inner boundary, in two different background solar winds. One of the resulting events is a blob-like stealth CME occurring in the trailing current sheet of its predecessor. We compared some of these scenarios with an observed event, starting from the Sun and during their propagation to Earth. The geomagnetic impact of all the simulated CMEs was also analyzed, as well as the effect of following eruptions onto the structure and dynamics of the preceding  CMEs with which they interact. The final part of this research involved the analysis of the forces contributing to the evolution of these consecutive eruptions. This provided a deeper  understanding of the mechanisms involved in the ‘CME-CME’ and ‘CME-background solar wind’

About the Speaker

Dana Talpeanu received her Ph.D in Mathematics from KU Leuven in June 2022. During her thesis project, she studied the factors contributing to the initiation and propagation of stealth coronal mass ejections by means of numerical simulations, but also through observations from different spacecraft. She analyzed the influence of previous eruptions during sympathetic events and the contribution of the background solar wind on the resulting geoeffectiveness. In parallel, ever since her
master thesis she has been fascinated by coronal fans and would wish to study how they fit in the complete picture of the solar corona. She is currently working on a variety of topics as an instrument scientist at the Royal Observatory of Belgium, including detector testing and calibration, data analysis and spacecraft operations