Related papers: Modelling the Global Solar Corona II: Coronal Evol…
The evolution of a coronal loop is studied by means of numerical simulations of the fully compressible three-dimensional magnetohydrodynamic equations using the HYPERION code. The footpoints of the loop magnetic field are advected by random…
We review recent insights into the dynamics of the solar convection zone obtained from global numerical simulations, focusing on two recent developments in particular. The first is quasi-cyclic magnetic activity in a long-duration dynamo…
The calling card of solar magnetism is the sunspot cycle, during which sunspots regularly reverse their polarity sense every 11 years. However, a number of more complicated time-dependent behaviors have also been identified. In particular,…
Solar coronal loops are commonly subject to oscillations. Observations of coronal oscillations are used to infer physical properties of the coronal plasma using coronal seismology. Excitation and evolution of oscillations in coronal loops…
Understanding the three-dimensional evolution of coronal magnetic fields during solar flares remains challenging due to the lack of direct coronal field measurements. Here we combine data-driven MHD simulations of NOAA AR 11158 (Fan et al.,…
The solar active region photospheric magnetic field evolves rapidly during major eruptive events, suggesting appreciable feedback from the corona. Previous studies of these "magnetic imprints" are mostly based on line-of-sight only or…
Solar filaments show the position of large scale polarity inversion lines and are used for the reconstruction of large-scale solar magnetic field structure on the basis of H{\alpha} synoptic charts for the periods when magnetographic…
Filaments which form either between or around active regions (ARs) are called intermediate filaments. In spite of various theoretical studies, the origin of the chirality of filaments is still uncovered. We investigated how intermediate…
To understand the magnetic fields of the polar crown filaments (PCFs) at high latitudes near polar regions of the Sun, we perform magnetofrictional numerical simulations on the long-term magnetic evolution of bipolar fields with roughly…
In this Letter, we investigate the long-duration quasi-static evolution of 12 pre-eruptive filaments (4 active region and 8 quiescent filaments), mainly focusing on the evolution of the filament height in three dimension (3D) and the decay…
We study the magnetic field evolution in the active region (AR) 12673 that produced the largest solar flare in the past decade on 2017 September 6. Fast flux emergence is one of the most prominent features of this AR. We calculate the…
Photospheric magnetic field not only plays important roles in building up free energy and triggering solar eruptions, but also has been observed to change rapidly and permanently responding to the coronal magnetic field restructuring due to…
Using a 3D non-linear mean-field solar dynamo model, we investigate the magnetic helicity flux and magnetic twist, and tilt parameters of bipolar magnetic regions (BMRs) emerging from the solar convection zone due to the magnetic buoyancy…
The magnetic cycle on the Sun consists of two consecutive 11-yr sunspot cycles and exhibits a polarity reversal around sunspot maximum. Although solar dynamo theories have progressively become more sophisticated, the details as to how the…
The Sun's magnetic field is a key driver in coronal heating and consequently solar wind acceleration. Remote measurement of the photosphere provides the magnetic surface boundary condition necessary for data-constrained 3D global coronal…
Coronal jets are observed above minority polarity intrusions throughout the solar corona. Some of the most energetic occur on the periphery of active regions where the magnetic field is strongly inclined. These jets exhibit a non-radial…
Magnetic reconnection, the rearrangement of magnetic field topology, is a fundamental physical process in magnetized plasma systems all over the universe1,2. Its process is difficult to be directly observed. Coronal structures, such as…
When we examine the chirality or observed handedness of the chromospheric and coronal structures involved in the long-term build-up to eruptive events, we find that they evolve in very specific ways to form two and only two sets of…
We develop a two-scale formalism to determine global magnetic helicity spectra in systems where the local magnetic helicity has opposite signs on both sides of the equator, giving rise to cancelation with conventional methods. We verify…
Magnetic helicity quantifies how globally sheared and/or twisted is the magnetic field in a volume. This quantity is believed to play a key role in solar activity due to its conservation property. Helicity is continuously injected into the…