TY - JOUR
T1 - Deciphering solar coronal heating
T2 - energizing small-scale loops through surface convection
AU - Nóbrega-Siverio, D.
AU - Moreno-Insertis, F.
AU - Galsgaard, K.
AU - Krikova, K.
AU - Rouppe van der Voort, L.
AU - Joshi, R.
AU - Madjarska, M. S.
N1 - Funding: This research has been supported by the European Research Council through the Synergy grant No. 810218 ("The Whole Sun," ERC-2018-SyG); by the Spanish Ministry of Science, Innovation and Universities through project PGC2018-095832-B-I00; and by the Research Council of Norway (RCN) through its Centres of Excellence scheme, project number 262622. The authors acknowledge the computer resources at the MareNostrum supercomputing installation and the technical support provided by the Barcelona Supercomputing Center (BSC, RES-AECT-2021-1-0023, RES-AECT-2022-2-0002). The use of UCAR's VAPOR software (Li et al. 2019; Pearse et al. 2023) is gratefully acknowledged. This work also benefited from discussions at the International Space Science Institute (ISSI) in Bern, through ISSI International Team project #535 Unraveling surges: a joint perspective from numerical models, observations, and machine learning. L.R.v.d.V. is supported by RCN project number 325491. M.M. acknowledges financial support by DFG grant WI 3211/8-1. The Swedish 1-m Solar Telescope is operated on the island of La Palma by the Institute for Solar Physics of Stockholm University in the Spanish Observatorio del Roque de Los Muchachos of the Instituto de Astrofísica de Canarias. The Institute for Solar Physics is supported by a grant for research infrastructures of national importance from the Swedish Research Council (registration number 2017-00625). SDO observations are courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.
PY - 2023/12/1
Y1 - 2023/12/1
N2 - The solar atmosphere is filled with clusters of hot small-scale loops commonly known as coronal bright points (CBPs). These ubiquitous structures stand out in the Sun by their strong X-ray and/or extreme-ultraviolet (EUV) emission for hours to days, which makes them a crucial piece when solving the solar coronal heating puzzle. In addition, they can be the source of coronal jets and small-scale filament eruptions. Here we present a novel 3D numerical model using the Bifrost code that explains the sustained CBP heating for several hours. We find that stochastic photospheric convective motions alone significantly stress the CBP magnetic field topology, leading to important Joule and viscous heating concentrated around the CBP's inner spine at a few megameters above the solar surface. We also detect continuous upflows with faint EUV signals resembling observational dark coronal jets and small-scale eruptions when Hα fibrils interact with the reconnection site. We validate our model by comparing simultaneous CBP observations from the Solar Dynamics Observatory (SDO) and the Swedish 1‐m Solar Telescope (SST) with observable diagnostics calculated from the numerical results for EUV wavelengths as well as for the Hα line using the Multi3D synthesis code. Additionally, we provide synthetic observables to be compared with Hinode, Solar Orbiter, and the Interface Region Imaging Spectrograph (IRIS). Our results constitute a step forward in the understanding of the many different facets of the solar coronal heating problem.
AB - The solar atmosphere is filled with clusters of hot small-scale loops commonly known as coronal bright points (CBPs). These ubiquitous structures stand out in the Sun by their strong X-ray and/or extreme-ultraviolet (EUV) emission for hours to days, which makes them a crucial piece when solving the solar coronal heating puzzle. In addition, they can be the source of coronal jets and small-scale filament eruptions. Here we present a novel 3D numerical model using the Bifrost code that explains the sustained CBP heating for several hours. We find that stochastic photospheric convective motions alone significantly stress the CBP magnetic field topology, leading to important Joule and viscous heating concentrated around the CBP's inner spine at a few megameters above the solar surface. We also detect continuous upflows with faint EUV signals resembling observational dark coronal jets and small-scale eruptions when Hα fibrils interact with the reconnection site. We validate our model by comparing simultaneous CBP observations from the Solar Dynamics Observatory (SDO) and the Swedish 1‐m Solar Telescope (SST) with observable diagnostics calculated from the numerical results for EUV wavelengths as well as for the Hα line using the Multi3D synthesis code. Additionally, we provide synthetic observables to be compared with Hinode, Solar Orbiter, and the Interface Region Imaging Spectrograph (IRIS). Our results constitute a step forward in the understanding of the many different facets of the solar coronal heating problem.
U2 - 10.3847/2041-8213/ad0df0
DO - 10.3847/2041-8213/ad0df0
M3 - Letter
AN - SCOPUS:85180100817
SN - 2041-8205
VL - 958
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
IS - 2
M1 - L38
ER -