Related papers: Data-driven model of the solar corona above an act…
Solar eruptions arise from instabilities or loss of equilibria in the solar atmosphere, but routinely inferring the precise magnetic and plasma properties that lead to eruptions is not currently practical using synoptic solar observations.…
The corona of the Sun is dominated by emission from loop-like structures. When observed in X-ray or extreme ultraviolet emission, these million K hot coronal loops show a more or less constant cross section. In this study we show how the…
A forward model is described in which we synthesize spectra from an ab-initio 3D MHD simulation of an outer stellar atmosphere, where the coronal heating is based on braiding of magnetic flux due to photospheric footpoint motions. We…
The nature and detailed properties of the heating of the million-degree solar corona are important issues that are still largely unresolved. Nanoflare heating might be dominant in active regions and quiet Sun, although direct signatures of…
The outer solar atmosphere, the corona, contains plasma at temperatures of more than a million K, more than 100 times hotter that solar surface. How this gas is heated is a fundamental question tightly interwoven with the structure of the…
The solar atmosphere may be heated by Alfven waves that propagate up from the convection zone and dissipate their energy in the chromosphere and corona. To further test this theory, we consider wave heating in an active region observed on…
A major goal in solar physics has during the last five decades been to find how energy flux generated in the solar convection zone is transported and dissipated in the outer solar layers. Progress in this field has been slow and…
Many studies of the solar corona have shown that the observed X-ray luminosity is well correlated with the total unsigned magnetic flux. In this paper we present results from the extensive numerical modeling of active regions observed with…
Coronal extreme-ultraviolet (EUV) waves are large-scale disturbances propagating in the corona, whose physical nature and origin have been discussed for decades. We report the first three dimensional (3D) radiative magneto-hydrodynamic…
Context. The structure and heating of coronal loops are investigated since decades. Established scaling laws relate fundamental quantities like the loop apex temperature, pressure, length, and the coronal heating. Aims. We test such scaling…
Although the mechanisms responsible for heating the Sun's corona and accelerating the solar wind are still being actively investigated, it is largely accepted that photospheric motions provide the energy source and that the magnetic field…
2.5-dimensional magnetohydrodynamic (MHD) simulations are performed with high spatial resolution in order to distinguish between competing models of the coronal heating problem. A single coronal loop powered by Alfv\'{e}n waves excited in…
We present first results of the hybrid data-driven magnetofrictional (MF) and data-constrained magnetohydrodynamic (MHD) simulations of solar active region NOAA 11158, which produced an X-class flare and coronal mass ejection on 2011…
A 3D model intermediate between cellular automata (CA) models and the reduced magnetohydrodynamic (RMHD) equations is presented to simulate solar impulsive events generated along a coronal magnetic loop. The model consists of a set of…
We present a method of conducting data-driven simulations of solar active regions and flux emergence with the MURaM radiative magnetohydrodynamics (MHD) code. The horizontal electric field derived from the full velocity and magnetic…
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…
Solar energetic events are caused by the release of magnetic energy accumulated in the solar atmosphere. To understand their initiating physical mechanisms, the dynamics of the coronal magnetic fields must be studied. Unfortunately, the…
Magnetohydrodynamic (MHD) waves and/or the braiding of magnetic field lines are largely thought to be responsible for heating the solar corona, both being mechanisms which are driven by the Sun's photospheric magnetic field. Recent…
In this paper, we report the observed temporal correlation between extreme-violet (EUV) emission and magneto-acoustic oscillations in a EUV moss region, which is the footpoint region only connected by magnetic loops with million-degree…
The "middle corona" is a critical transition between the highly disparate physical regimes of the lower and outer solar corona. Nonetheless, it remains poorly understood due to the difficulty of observing this faint region (1.5-3 solar…