Results 21 to 30 of about 27,444 (310)
Expulsion of Counter Evershed Flows from Sunspot Penumbrae
The Astrophysical Journal, 2023 In addition to the Evershed flow directed from the umbra toward the outer boundary of a sunspot, under special circumstances a counter Evershed flow (CEF) in the opposite direction also occurs.
J. S. Castellanos Durán +2 more
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Rapid Decay of a Penumbral Sector Associated with a Strong Light Bridge in Active Region NOAA 12680
The Astrophysical Journal, 2023 We present observations of the rapid decay of a penumbral sector associated with a strong light bridge (LB) in the active region NOAA 12680 by analyzing the scattered light-corrected Solar Dynamics Observatory/Helioseismic and Magnetic Imager data.
Qiaoling Li +5 more
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Magnetic Fields of Solar Active Regions [PDF]
Proceedings of the International Astronomical Union, 2004 After briefly summarizing the outstanding achievements and new tendencies witnessed in recent years in the studies of magnetic fields of solar active regions (ARs), we focus on the current understanding on flux appearance and disappearance. On flux appearance, the moving magnetic features (MMFs) stand still as a mystery in solar physics, although the ...
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The Astrophysical Journal, 2023 We analyze the forces that control the dynamic evolution of a flux rope eruption in a three-dimensional radiative magnetohydrodynamic simulation. The confined eruption of the flux rope gives rise to a C8.5 flare. The flux rope rises slowly with an almost
Can Wang +3 more
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PROBING THE SHALLOW CONVECTION ZONE: RISING MOTION OF SUBSURFACE MAGNETIC FIELDS IN THE SOLAR ACTIVE REGION [PDF]
, 2013 In this Letter, we present a seismological detection of a rising motion of magnetic flux in the shallow convection zone of the Sun, and show estimates of the emerging speed and its decelerating nature.
S. Toriumi +3 more
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MODELING MAGNETIC FIELD STRUCTURE OF A SOLAR ACTIVE REGION CORONA USING NONLINEAR FORCE-FREE FIELDS IN SPHERICAL GEOMETRY [PDF]
, 2012 We test a nonlinear force-free field (NLFFF) optimization code in spherical geometry using an analytical solution from Low and Lou. Several tests are run, ranging from idealized cases where exact vector field data are provided on all boundaries, to cases
Y. Guo +5 more
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Magnetic fields in the solar convection zone
Living Reviews in Solar Physics, 2021 It has been a prevailing picture that active regions on the solar surface originate from a strong toroidal magnetic field stored in the overshoot region at the base of the solar convection zone, generated by a deep seated solar dynamo mechanism.
Yuhong Fan
semanticscholar +1 more source
The Astrophysical Journal, 2023 The nonassociation of coronal mass ejections with high energetic flares is sparse. For this reason, the magnetic conditions required for the confinedness of major flares is a topic of active research.
N. Vasantharaju +3 more
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Magnetic Field Topology in Solar Active Regions [PDF]
International Astronomical Union Colloquium, 1993 AbstractIn solar active regions, over extended periods of time the plasma-magnetic field configuration evolves quasistatically through a sequence of nearly force-free equilibrium states. This evolution may be understood as the continual distortion of an existing equilibrium by wavelike disturbances propagating upward from the photosphere and subsequent
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Solar Flare Prediction and Magnetic Field Evolution in Solar Active Region [PDF]
Highlights of Astronomy, 2002 AbstractThe authors propose a number of empirical criteria for prediction of solar flares based on many years of observations at Huairou Solar Observing Station of Beijing Astronomical Observatory.
H.N. Wang +3 more
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