What physical mechanisms heat the outer solar or stellar atmosphere to million-kelvin temperatures is a fundamental but long-standing open question. In particular, the solar corona in active-region cores contains an even hotter component reaching 10 MK, manifesting as persistent coronal loops in extreme ultraviolet and soft X-ray images, which imposes a stringent energy budget. Here, we present a self-consistent coronal heating model using a state-of-the-art three-dimensional radiative magnetohydrodynamics simulation. We find that the continuous emergence of magnetic flux in active regions keeps driving magnetic reconnections that release energy impulsively but are persistent over time on average. As a result, numerous substructures are heated to 10 MK and then evolve independently. These collectively form the long-lived and stable coronal loops that have been observed. This process provides a heating model that explains the origin of the super-hot coronal plasma and the persistence of hot coronal loops in emerging active regions.
https://www.nature.com/articles/s41550-024-02244-5
BIO
Zekun Lu is a PhD candidate at School of Astronomy and Space Science of Nanjing University. He completed his Bachelor's degree in Astronomy at Nanjing University in 2018. Then, he worked with Prof. Dmitri Pogosyan at University of Alberta and received his Master's degree in Physics in 2020. Currently, he is working with Prof. Mingde Ding and Prof. Feng Chen at Nanjing University Solar Physics group. His research focuses on studying coronal heating, cooling, and related energy-release activities in solar active regions.
