[P-EM11] Frontiers in solar physics

[PEM11-P05] Testing a coronal heating model of the young Sun through Model-Observation Comparisons

*Bumpei Sakamoto¹, Munehito Shoda¹, Shinsuke Imada¹ (1.Department of Earth and Planetary Science, School of Science, The University of Tokyo)

Keywords:Solar corona

The stellar corona is the primary source of stellar XUV (X-ray and extreme ultraviolet) emissions, which significantly influence planetary atmospheric evolution. Understanding the long-term history of the solar corona is essential for reconstructing the history of the solar system. A major challenge in estimating the young Sun’s high-energy emission is the difficulty of directly observing XUV radiation. Because of this, numerical modeling is essential for determining the emission rate.The purpose of this study is to examine whether a model, capable of reproducing the solar XUV emission, is applicable to young solar-type stars. To achieve this, we modeled the coronal emissions of solar-type stars with varying surface magnetic fluxes, where the surface magnetic flux serves as a proxy for stellar age. For each run, we computed the fluxes of emission lines over various formation temperatures. The emission line flux and surface magnetic flux follow a power-law relationship, with the index dependent on the line formation temperature. We observe that the power-law indices vary with formation temperature, following the same trend as in observations, where higher temperatures correspond to larger indices. Compared to previous studies, our findings demonstrate that the model can explain observations even in the wavelength range longer than 912 Å. Our results indicate that the current solar coronal heating model is applicable to young Sun, although further observational validations are necessary for a more comprehensive model assessment.