Related papers: Electric Current Equilibrium in the Corona
We review and discuss insights on ideal magnetohydrodynamic (MHD) instabilities that can play a role in destabilizing solar coronal flux rope structures. For single flux ropes, failed or actual eruptions may result from internal or external…
A close association between eruptive prominences and CMEs, both slow and fast CMEs, was reported in many studies. Sometimes it is possible to follow the material motion starting from the prominence (filament) activation to the CME in the…
The formation of the observed core-halo feature in the solar wind electron velocity distribution function is a long-time puzzle. In this letter based on the current knowledge of nanoflares we show that the nanoflare-accelerated electron…
Non-thermal particle acceleration in the solar corona is evident from both remote hard X-ray (HXR) sources in the chromosphere and direct in-situ detection in the heliosphere. Correlation of spectral indices between remote and in-situ…
Coronal rain is ubiquitous in flare loops, forming shortly after the onset of the solar flare. Rain is thought to be caused by a thermal instability, a localized runaway cooling of material in the corona. The models that demonstrate this…
There has been a long-lasting debate on the question of whether or not electric currents in solar active regions are neutralized. That is, whether or not the main (or direct) coronal currents connecting the active region polarities are…
Coronal loops act as resonant cavities for low frequency fluctuations that are transmitted from the deeper layers of the solar atmosphere and are amplified in the corona, triggering nonlinear interactions. However trapping is not perfect,…
Observations have shown a clear association of filament/prominence eruptions with the emergence of magnetic flux in or near filament channels. Magnetohydrodynamic (MHD) simulations have been employed to systematically study the conditions…
We report a new, plasmoid-fed scenario for the formation of an eruptive prominence (PF$^2$), involving reconnection and condensation. We use grid-adaptive resistive two-and-a-half-dimensional magnetohydrodynamic (MHD) simulations in a…
A large number of energetic electrons are generated during solar flares. They carry a substantial part of the flare released energy but how these electrons are created is not fully understood yet. This paper suggests that plasma motion in…
Recent Solar Dynamic Observatory observations reveal that coronal mass ejections (CMEs) consist of a multi-temperature structure: a hot flux rope and a cool leading front (LF). The flux rope first appears as a twisted hot channel in the…
Current sheets are essential for energy dissipation in the solar corona, in particular by enabling magnetic reconnection. Unfortunately, sufficiently thin current sheets cannot be resolved observationally and the theory of their formation…
The dynamic properties of flare ribbons and the often associated filament eruptions can provide crucial information on the flaring coronal magnetic field. This Letter analyzes the GOES-class X1.0 flare on 2014 March 29…
Coronae exist in most astrophysical objects: stars, accretion disks, and individual galaxies and clusters of galaxies. Coronae in these varied systems have some common properties: 1) hydrostatic equilibrium in background gravity is a good…
Coronal magnetic flux ropes are generally considered to be the core structure of large-scale solar eruptions. Recent observations found that solar eruptions could be initiated by a sequence of "flux feeding," during which chromospheric…
Solar atmospheric elemental abundances are now known to vary both in space and time. Dynamic modeling of these changes is therefore necessary to improve the accuracy of radiative hydrodynamic simulations. Recent studies have shown that…
Erupting flux ropes play crucial role in powering a wide range of solar transients, including flares, jets, and coronal mass ejections. These events are driven by the release of stored magnetic energy, facilitated by the shear in the…
We study the modes and stability of non - isothermal coronal loop models with different intensity values of the equilibrium magnetic field. We use an energy principle obtained via non - equilibrium thermodynamic arguments. The principle is…
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…
Elemental abundances in the solar corona are known to be different from those observed in the solar photosphere. The ratio of coronal to photospheric abundance shows a dependence on the first ionisation potential (FIP) of the element. We…