Science Media

Data-driven model of temporal evolution of the solar Mg II h and k profiles over the solar cycle | Július Koza

44 views

ESPOS videos

03.04.2024

Co-author

Stanislav Gunár (The Czech Academy of Sciences, Czech Republic), Pavol Schwartz (Slovak Academy of Sciences, Slovakia), Petr Heinzel (The Czech Academy of Sciences, Czech Republic; University of Wrocław, Poland), Wenjuan Liu (The Czech Academy of Sciences, Czech Republic)

Affiliation

Astronomical Institute, Slovak Academy of Sciences, Slovakia

Main category

Natural Sciences (Astrophysics and Astrononmy)

Caption

The solar radiation in the cores of the Mg II h & k spectral lines strongly correlates with solar magnetic activity and global variations of magnetic fields with the solar cycle. This work provides a data-driven model of temporal evolution of the solar full-disk Mg II h & k profiles over the solar cycle. Based on selected 76 IRIS near-UV full-Sun mosaics covering almost the full solar cycle 24, we find the parameters of double-Gaussian fits of the disk-averaged Mg II h & k profiles and a model of their temporal evolution parameterized by the Bremen composite Mg II index. Read more at https://espos.stream/2024/03/21/Koza/.

Further information

Errata: The first slide, illustrating irradiation of spicule-like jet by disk radiation, suggests that the incident radiation from the solar disk is formally designated as \bar{J}. However, this is not correct notation because \bar{J} has a different meaning. It is the profile-weighted mean radiation intensity, integrated over the spectral line. See Eq. (2.52) in Rutten (2003). \bar{J} appears in the equations of statistical equilibrium. In fact, the incident radiation from the solar disk defines the boundary conditions in the radiative transfer equation. It is represented in the non-LTE codes as a specific intensity of irradiation or as a mean intensity of irradiation.