scholarly journals A Three-dimensional Study of Reconnection, Current Sheets, and Jets Resulting from Magnetic Flux Emergence in the Sun

2004 ◽  
Vol 618 (2) ◽  
pp. L153-L156 ◽  
Author(s):  
K. Galsgaard ◽  
F. Moreno-Insertis ◽  
V. Archontis ◽  
A. Hood
Keyword(s):  
Magnetic Flux ◽  
Three Dimensional ◽  
The Sun ◽  
Flux Emergence ◽  
Current Sheets

scholarly journals Energetics of magnetic transients in a solar active region plage

2019 ◽  
Vol 623 ◽  
pp. A176 ◽  
Author(s):  
L. P. Chitta ◽  
A. R. C. Sukarmadji ◽  
L. Rouppe van der Voort ◽  
H. Peter
Keyword(s):  
Magnetic Field ◽  
Active Region ◽  
Magnetic Flux ◽  
Numerical Simulations ◽  
Extreme Ultraviolet ◽  
Spatial Scales ◽  
Coronal Loops ◽  
The Sun ◽  
Flux Emergence ◽  
Transient Events

Context. Densely packed coronal loops are rooted in photospheric plages in the vicinity of active regions on the Sun. The photospheric magnetic features underlying these plage areas are patches of mostly unidirectional magnetic field extending several arcsec on the solar surface. Aims. We aim to explore the transient nature of the magnetic field, its mixed-polarity characteristics, and the associated energetics in the active region plage using high spatial resolution observations and numerical simulations. Methods. We used photospheric Fe I 6173 Å spectropolarimetric observations of a decaying active region obtained from the Swedish 1-m Solar Telescope (SST). These data were inverted to retrieve the photospheric magnetic field underlying the plage as identified in the extreme-ultraviolet emission maps obtained from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO). To obtain better insight into the evolution of extended unidirectional magnetic field patches on the Sun, we performed 3D radiation magnetohydrodynamic simulations of magnetoconvection using the MURaM code. Results. The observations show transient magnetic flux emergence and cancellation events within the extended predominantly unipolar patch on timescales of a few 100 s and on spatial scales comparable to granules. These transient events occur at the footpoints of active region plage loops. In one case the coronal response at the footpoints of these loops is clearly associated with the underlying transient. The numerical simulations also reveal similar magnetic flux emergence and cancellation events that extend to even smaller spatial and temporal scales. Individual simulated transient events transfer an energy flux in excess of 1 MW m−2 through the photosphere. Conclusions. We suggest that the magnetic transients could play an important role in the energetics of active region plage. Both in observations and simulations, the opposite-polarity magnetic field brought up by transient flux emergence cancels with the surrounding plage field. Magnetic reconnection associated with such transient events likely conduits magnetic energy to power the overlying chromosphere and coronal loops.

Magnetic Flux Emergence into the Solar Corona. II. Global Magnetic Fields with Current Sheets

2002 ◽  
Vol 576 (2) ◽  
pp. 1005-1017 ◽  
Author(s):  
M. Zhang ◽  
B. C. Low
Keyword(s):  
Magnetic Fields ◽  
Magnetic Flux ◽  
Solar Corona ◽  
Flux Emergence ◽  
Current Sheets

Magnetic Flux Emergence, Activity, Eruptions and Magnetic Clouds: Following Magnetic Field from the Sun to the Heliosphere

2008 ◽  
Vol 144 (1-4) ◽  
pp. 351-381 ◽  
Author(s):  
L. van Driel-Gesztelyi ◽  
J. L. Culhane
Keyword(s):  
Magnetic Field ◽  
Magnetic Flux ◽  
Magnetic Clouds ◽  
The Sun ◽  
Flux Emergence

scholarly journals Relationships Between Sequential Chromospheric Brightening and the Corona

2016 ◽  
Vol 12 (S327) ◽  
pp. 117-127
Author(s):  
M. S. Kirk ◽  
K. S. Balasubramaniam ◽  
J. Jackiewicz ◽  
H. R. Gilbert
Keyword(s):  
Magnetic Flux ◽  
Coronal Mass Ejection ◽  
Fast Moving ◽  
Atmospheric Environment ◽  
The Sun ◽  
Flux Emergence ◽  
Complex Region ◽  
Magnetic Features ◽  
Mass Ejection ◽  
Early Indication

AbstractThe chromosphere is a complex region that acts as an intermediary between the magnetic flux emergence in the photosphere and the magnetic features seen in the corona. Large eruptions in the chromosphere of flares and filaments are often accompanied by ejections of coronal mass off the sun. Several studies have observed fast-moving progressive trains of compact bright points (called Sequential Chromospheric Brightenings or SCBs) streaming away from chromospheric flares that also produce a coronal mass ejection (CME). In this work, we review studies of SCBs and search for commonalties between them. We place these findings into a larger context with contemporary chromospheric and coronal observations. SCBs are fleeting indicators of the solar atmospheric environment as it existed before their associated eruption. Since they appear at the very outset of a flare eruption, SCBs are good early indication of a CME measured in the chromosphere.

scholarly journals The emergence of magnetic flux and its role on the onset of solar dynamic events

2019 ◽  
Vol 377 (2148) ◽  
pp. 20180387 ◽  
Author(s):  
V. Archontis ◽  
P. Syntelis
Keyword(s):  
Magnetic Flux ◽  
Large Scale ◽  
Spatial Scales ◽  
Active Regions ◽  
Short Review ◽  
The Sun ◽  
Flux Emergence ◽  
Dynamic Events ◽  
Solar Eruptions ◽  
Solar Dynamics

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 with the emergence of magnetic flux from the interior of the Sun to the surface and above. Here, we present a short review on the onset, driving and/or triggering of such events by magnetic flux emergence. We briefly describe some key observational examples, theoretical aspects and numerical simulations, towards revealing the mechanisms that govern solar dynamics and activity related to flux emergence. We show that the combination of important physical processes like shearing and reconnection of magnetic fieldlines in emerging flux regions or at their vicinity can power some of the most dynamic phenomena in the Sun on various temporal and spatial scales. Based on previous and recent observational and numerical studies, we highlight that, in most cases, none of these processes alone can drive and also trigger explosive phenomena releasing considerable amount of energy towards the outer solar atmosphere and space, such as flares, jets and large-scale eruptions (e.g. coronal mass ejections). In addition, one has to take into account the physical properties of the emerging field (e.g. strength, amount of flux, relative orientation to neighbouring and pre-existing magnetic fields, etc.) in order to better understand the exact role of magnetic flux emergence on the onset of solar dynamic events. This article is part of the theme issue ‘Solar eruptions and their space weather impact’.

scholarly journals Magnetic flux emergence and associated dynamic phenomena in the Sun

2012 ◽  
Vol 370 (1970) ◽  
pp. 3088-3113 ◽  
Author(s):  
Vasilis Archontis
Keyword(s):  
Magnetic Fields ◽  
Magnetic Flux ◽  
Numerical Experiments ◽  
Solar Interior ◽  
The Sun ◽  
Flux Emergence ◽  
Dynamic Events ◽  
Comprehensive Picture ◽  
Potential Applications ◽  
Dynamic Phenomena

We present a review of the process of magnetic flux emergence in the Sun. We focus on observations and numerical experiments that explore the dynamical rise of magnetic fields from the solar interior to the corona. We describe the response of the highly stratified solar atmosphere on flux emergence and, consequently, we present a comprehensive picture of the coupling between solar dynamic events and flux emergence. We discuss potential applications of this process in other astrophysical environments.

scholarly journals Three-dimensional magnetohydrodynamic simulation of the solar magnetic flux emergence

2013 ◽  
Vol 553 ◽  
pp. A55 ◽  
Author(s):  
S. Toriumi ◽  
T. Yokoyama
Keyword(s):  
Magnetic Flux ◽  
Three Dimensional ◽  
Flux Emergence ◽  
Magnetohydrodynamic Simulation

scholarly journals Flux Separation in Photospheric Magnetoconvection

2001 ◽  
Vol 203 ◽  
pp. 219-221 ◽  
Author(s):  
N. O. Weiss ◽  
M. R. E. Proctor
Keyword(s):  
Magnetic Field ◽  
Magnetic Flux ◽  
Numerical Experiments ◽  
Large Scale ◽  
Initial Conditions ◽  
Three Dimensional ◽  
Small Scale ◽  
The Sun ◽  
Intermediate Regime ◽  
Magnetic Features

Numerical experiments on three-dimensional magnetoconvection in a stratified compressible layer reveal a range of different patterns, depending on the strength of the imposed magnetic field. As the field is decreased there is a transition from small-scale plumes, in the magnetically dominated regime, to large-scale vigorous plumes when the field is dominated by the motion. In the intermediate regime magnetic flux separates from the motion, so that there are almost field-free regions, with clusters of vigorous plumes, surrounded by regions where the Lorentz force is strong enough to control the dynamics. There is a range of field strengths where either small-scale plumes or flux-separated solutions can persist, depending on initial conditions for the computation. These results can be related to magnetic features at the surface of the Sun.

scholarly journals RECURRENT EXPLOSIVE ERUPTIONS AND THE “SIGMOID-TO-ARCADE” TRANSFORMATION IN THE SUN DRIVEN BY DYNAMICAL MAGNETIC FLUX EMERGENCE

2014 ◽  
Vol 786 (2) ◽  
pp. L21 ◽  
Author(s):  
V. Archontis ◽  
A. W. Hood ◽  
K. Tsinganos
Keyword(s):  
Magnetic Flux ◽  
Explosive Eruptions ◽  
The Sun ◽  
Flux Emergence
Sign in / Sign up

Export Citation Format

Share Document