학술논문
Fleeting Small-scale Surface Magnetic Fields Build the Quiet-Sun Corona
Document Type
Working Paper
Author
Chitta, L. P.; Solanki, S. K.; Iniesta, J. C. del Toro; Woch, J.; Calchetti, D.; Gandorfer, A.; Hirzberger, J.; Kahil, F.; Valori, G.; Suárez, D. Orozco; Strecker, H.; Appourchaux, T.; Volkmer, R.; Peter, H.; Mandal, S.; Cuadrado, R. Aznar; Teriaca, L.; Schühle, U.; Berghmans, D.; Verbeeck, C.; Zhukov, A. N.; Priest, E. R.
Source
ApJL 956, L1 (2023)
Subject
Language
Abstract
Arch-like loop structures filled with million Kelvin hot plasma form the building blocks of the quiet-Sun corona. Both high-resolution observations and magnetoconvection simulations show the ubiquitous presence of magnetic fields on the solar surface on small spatial scales of $\sim$100\,km. However, the question of how exactly these quiet-Sun coronal loops originate from the photosphere and how the magnetic energy from the surface is channeled to heat the overlying atmosphere is a long-standing puzzle. Here we report high-resolution photospheric magnetic field and coronal data acquired during the second science perihelion of Solar Orbiter that reveal a highly dynamic magnetic landscape underlying the observed quiet-Sun corona. We found that coronal loops often connect to surface regions that harbor fleeting weaker, mixed-polarity magnetic field patches structured on small spatial scales, and that coronal disturbances could emerge from these areas. We suggest that weaker magnetic fields with fluxes as low as $10^{15}$\,Mx and/or those that evolve on timescales less than 5\,minutes, are crucial to understand the coronal structuring and dynamics.
Comment: Published in The Astrophysical Journal Letters
Comment: Published in The Astrophysical Journal Letters