Blue-wing enhancement of the chromospheric Mg II h and k lines in a solar flare

0499723 - ASÚ 2019 RIV JP eng J - Journal Article
Tei, A. - Sakaue, T. - Okamoto, T. J. - Kawate, T. - Heinzel, Petr - Ueno, S. - Asai, A. - Ichimoto, K. - Shibata, K.
Blue-wing enhancement of the chromospheric Mg II h and k lines in a solar flare.
Publications of the Astronomical Society of Japan. Roč. 70, č. 6 (2018), č. článku 100. ISSN 0004-6264. E-ISSN 2053-051X
R&D Projects: GA ČR(CZ) GA16-18495S
Institutional support: RVO:67985815
Keywords : Sun * activity * chromosphere
OECD category: Astronomy (including astrophysics,space science)
Impact factor: 2.750, year: 2018

We performed coordinated observations of AR 12205, which showed a C-class flare on 2014 November 11, with the Interface Region Imaging Spectrograph (IRIS) and the Domeless Solar Telescope (DST) at Hida Observatory. Cloud modeling of the Mg II h line suggests that the blue-wing enhancement with such a peak difference could have been caused by a chromospheric-temperature (cool) upflow. We discuss a scenario in which an upflow of cool plasma is lifted up by expanding hot plasma owing to the deep penetration of non-thermal electrons into the chromosphere. Furthermore, we found that the blueshift persisted without any subsequent redshift in the leading edge of the flare kernel during its decaying phase. The cause of such a long-lasting blueshift is also discussed.
Permanent Link: http://hdl.handle.net/11104/0292057