Related papers: A Non-radial Eruption in a Quadrupolar Magnetic Co…
Solar flares abruptly release the free energy stored as a non-potential magnetic field in the corona and may be accompanied by eruptions of the coronal plasma. Formation of a non-potential magnetic field and the mechanisms for triggering…
We analyse multiwavelength observations of a western limb flare (C3.9) occurred in AR NOAA 111465 on 30 April 2012. The high resolution images recorded by SDO/AIA 304, 1600 \AA\ and Hinode/SOT H$\alpha$ show the activation of a…
On 10 March 2001 the active region NOAA 9368 produced an unusually impulsive solar flare in close proximity to the solar limb. This flare has previously been studied in great detail, with observations classifying it as a type 1 white-light…
We re-analyse spectropolarimetric data of AB Dor taken in 1996 December using a surface imaging code that can model the magnetic field of the star as a non-potential current-carrying magnetic field. We find that a non-potential field needs…
Erupting magnetic flux ropes (MFRs) play a crucial role in producing solar flares. However, the formation of erupting MFRs in complex coronal magnetic configurations and their subsequent evolution in the flaring events are not fully…
Low-temperature plasma ejected in solar eruptions can screen active regions as well as quiet solar areas. Absorption phenomena can be observed in microwaves as 'negative bursts' and in different spectral domains. We analyze two very…
The interaction between emerging magnetic flux and the pre-existing ambient field has become a "hot" topic for both numerical simulations and high-resolution observations of the solar atmosphere. The appearance of brightenings and surges…
We present AIA observations of a structure we interpret as a current sheet associated with an X4.9 flare and coronal mass ejection that occurred on 2014~February~25 in NOAA Active Region 11990. We characterize the properties of the current…
It has been found that photospheric magnetic fields can change in accordance with the three-dimensional magnetic field restructuring following solar eruptions. Previous studies mainly use vector magnetic field data taken for events near the…
Solar active regions (ARs) that produce strong flares and coronal mass ejections (CMEs) are known to have a relatively high non-potentiality and are characterized by delta-sunspots and sheared magnetic structures. In this study, we conduct…
We have observed formation of penumbrae on a pore in the active region NOAA10838 using Dunn Solar Telescope at NSO,Sunpot,USA. Simultaneous observations using different instruments (DLSP,UBF,Gband and CaK) provide us with vector magnetic…
Solar flares occur due to the sudden release of energy stored in active-region magnetic fields. To date, the pre-cursors to flaring are still not fully understood, although there is evidence that flaring is related to changes in the…
Current magnetohydrodynamic (MHD) simulations of the initiation of solar eruptions are still commonly carried out with idealized magnetic field models, whereas the realistic coronal field prior to eruptions can possibly be reconstructed…
We perform a data-constrained simulation with the zero-$\beta$ assumption to study the mechanisms of strong rotation and failed eruption of a filament in active region 11474 on 2012 May 5 observed by Solar Dynamics Observatory and Solar…
On 27 October, 2003, two GOES M-class flares occurred in the lapse of three hours in active region NOAA 10486. The two flares were confined and their associated brightenings appeared at the same location, displaying a very similar shape…
The magnetic breakout model has been widely used to explain solar eruptive activities. Here, we apply it to explain successive filament eruptions occurred in a quadrupolar magnetic source region. Based on the high temporal and spatial…
We have analyzed multi-wavelength observations and magnetic-field data for the solar flare of May 10, 2012 (04:18 UT) and have detected a sign inversion of the signal in the line-of-sight magnetic measurements in the umbra of a small spot.…
The magnetic fields in the solar corona are generally neither force-free nor axisymmetric and have complex dynamics that are difficult to characterize. Here we simulate the topological evolution of solar coronal magnetic field lines (MFLs)…
To better understand the structures of active-region filaments and the eruption process, we study an active-region filament eruption in active region NOAA 11082 in detail on June 22, 2010. Before the filament eruption, the opposite…
Solar eruptive behavior is often modeled with magnetohydrodynamic simulations of magnetic flux emergence. The usual geometry considered is that of a horizontal cylindrical magnetic flux tube. An alternative is the toroidal tube geometry…