Related papers: Flux emergence and coronal eruption
Both observations and simulations suggest that the solar filament eruption is closely related to magnetic flux emergence. It is thought that the eruption is triggered by magnetic reconnection between the filament and the emerging flux.…
Context. Data-constrained models incorporate observed photospheric magnetic fields. However, due to the lack of magnetic field information in the rest of the solar atmosphere, models rely on extrapolations that, in most cases, neglect the…
Magnetic flux emergence into the outer layers of the Sun is a fundamental mechanism for releasing energy into the chromosphere and the corona. In this paper, we study the emergence of granular-sized flux concentrations and the structuring…
Twisted magnetic fields should be ubiquitous in flare-producing active regions where the magnetic fields are strongly non-potential. It has been shown that reconnection in helical magnetic coronal loops results in plasma heating and…
The latitudinal distribution of starspots deviates from the solar pattern with increasing rotation rate. Numerical simulations of magnetic flux emergence and transport can help model the observed stellar activity patterns and the associated…
The eruption of the filament with the kink fashion is often regarded as a signature of the kink instability. However, the kink instability threshold for the filament magnetic structure has been not widely understood. Using the H-alpha…
Small-scale magnetic flux emergence in the quiet Sun is crucial for maintaining solar magnetic activity. On the smallest scales studied so far, namely within individual granules, two mechanisms have been identified: emergence in tiny…
Magnetic flux ropes are the centerpiece of solar eruptions. Direct measurements for the magnetic field of flux ropes are crucial for understanding the triggering and energy release processes, yet they remain heretofore elusive. Here we…
The buoyant transport of magnetic fields from the solar interior towards the surface plays an important role in the emergence of active regions, the formation of sunspots and the overall solar dynamo. Observations suggest that toroidal flux…
We analyse the evolution of a sigmoidal (S shaped) active region toward eruption, which includes a coronal mass ejection (CME) but leaves part of the filament in place. The X-ray sigmoid is found to trace out three different magnetic…
Sunspot proper motions and flares of a super active region NOAA 5395, which was the biggest and the most flare-active region in the 22nd sunspot cycle, were analyzed in details. We measured sunspot proper motions by using the H-alpha - 5.0…
Continuous observations were obtained of active region 10953 with the Solar Optical Telescope (SOT) on board the \emph{Hinode} satellite during 2007 April 28 to May 9. A prominence was located over the polarity inversion line (PIL) in the…
The magnetic network extending from the photosphere (solar radius $\simeq R_\odot$) to lower corona ($R_\odot + 10$ Mm) plays an important role in the heating mechanisms of the solar atmosphere. Here we further develop the models with…
A plethora of solar dynamic events, such as the formation of active regions, the emission of jets and the occurrence of eruptions is often associated to the emergence of magnetic flux from the interior of the Sun to the surface and above.…
Recent Sunrise/IMaX observations have revealed the existence of supersonic magnetic flows. Our aim is to determine the origin of such flows by using realistic MHD simulations. We simulate cancellation and emergence of magnetic flux through…
Observations of rapidly rotating solar-like stars show a significant mixture of opposite-polarity magnetic fields within their polar regions. To explain these observations, models describing the surface transport of magnetic flux demand the…
Force-freeness of a solar magnetic field is a key to reconstructing invisible coronal magnetic structure of an emerging flux region on the Sun where active phenomena such as flares and coronal mass ejections frequently occur. We have…
Context. Space weather and its potential negative consequences for life on Earth has received increasing attention in recent decades. Particularly predicting CME onset has become important from a security perspective. To predict CMEs, one…
Previous studies have found that coronal loops have a nearly uniform thickness, which seems to disagree with the characteristic expansion of active region magnetic fields. This is one of the most intriguing enigmas in solar physics. We here…
We investigated the dynamic evolution of a 3-dimensional (3D) flux rope eruption and magnetic reconnection process in a solar flare, by simply extending 2-dimensional (2D) resistive magnetohydrodynamic simulation model of solar flares with…