Digital Engineering Center's director, associate professor Tatiana Podladchikova (invited member) and PhD student and employee Galina Chikunova (early-career scientist) took part in the workshop of the International Space Sciences Institute (ISSI) on “Coronal dimmings and their relevance to the physics of solar and stellar coronal mass ejections” in Bern, Switzerland.

The team of ISSI workshop, supported by European Space Agency and Swiss Space Agency, includes also representatives of top international universities and companies from Europe, UK, USA, and China.
 
Coronal mass ejections (CMEs) are giant billion-ton magnetic plasma clouds expelled from the Sun that cause severe geomagnetic storms and spectacular polar auroras. However, the early evolution of CMEs, in particular Earth-directed ones, is difficult to trace with traditional coronagraphs and the estimation of CME properties is also challenging due to projections errors. The most distinct phenomena associated with CMEs are coronal dimmings - dark spots observed in the extreme-ultraviolet and soft X-rays that are associated with the loss of substance in the solar corona during the ejection of plasma.
 
The ISSI workshop team performs detailed multi-disciplinary studies on how the unique potential of coronal dimmings could be used for detection and characterization of solar and stellar CMEs. Skoltech team presented new-wave methods of using dimmings as an early indicator of the CME propagation direction, studies on dimming lifetime, how and when does the solar corona recover after a CME eruption, and how long are CMEs/flux ropes still connected to the Sun. The results include also contributions of PhD student and center employee Shantanu Jain and Erasmus student visiting Skoltech Giulia Maria Ronca and are developments of earlier joint studies between Skoltech and University of Graz (Austria) published in the Astrophysical Journal

1. https://doi.org/10.3847/1538-4357/ab9105 
2. https://doi.org/10.3847/1538-4357/ab0962 
3. https://doi.org/10.3847/1538-4357/aad3c6 
4. https://doi.org/10.3847/1538-4357/aaadb5 
 
The team is currently preparing for the second ISSI workshop to be held in 2023, working jointly on the first an up-to-date and detailed review article on coronal dimmings and their relevance in better understanding and characterizing solar and stellar CMEs. This will be the first review on coronal dimmings, 45 years after their detection.

Coronal dimmings and associated coronal mass ejecitons on 7 March 2012, SDO/AIA/SOHO/LASCO C2/C3.