Results 21 to 30 of about 11,108,449 (286)
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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Chromospheric Magnetic Field of Solar Active Regions
The Astrophysical Journal, 2001 The three-dimensional magnetic field structure of 137 solar active regions is studied by comparing the observed and computed chromospheric magnetograms. The model chromospheric field is obtained by extrapolating the observed photospheric field into the chromosphere with a potential (current-free) magnetic-field model in Cartesian geometry.
Debi Prasad Choudhary +2 more
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The Sun's global photospheric and coronal magnetic fields : observations and models [PDF]
, 2012 2012LRSP....9....6M Funding: STFC, the Leverhulme Trust and European Commission’s Seventh Framework Programme (FP7/2007-2013) under the grant agreement SWIFF (project no.
Anthony Yeates +6 more
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Development and application of a global magnetic field evolution model for the solar corona [PDF]
, 2009 Magnetic fields are fundamental to the structure and dynamics of the Sun’s corona. Observations show them to be locally complex, with highly sheared and twisted fields visible in solar filaments/prominences.
Yeates, Anthony Robinson
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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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The Sources of Magnetic Field Twist in Solar Active Regions [PDF]
The Astrophysical Journal, 2002 Observations have revealed that a hemispheric preference of magnetic chirality (handedness) exists throughout the solar atmosphere. For example, the current helicity of active regions is predominantly negative (left-handed twist) in the northern hemisphere and positive (right-handed twist) in the southern.
S. D. Bao, T. Sakurai, Y. Suematsu
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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
openaire +1 more source
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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The Initiation and Back-reaction of the X5.4 Flare on 2012 March 7
The Astrophysical Journal, 2023 In this paper, we study the evolution of the X5.4 flare (SOL2012-03-07T00:02) in NOAA Active Region 11429, focusing on its initiation mechanisms and back-reaction effects.
Nian Liu +4 more
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Solar flux emergence : a three-dimensional numerical study [PDF]
, 2008 Flux is continually emerging on the Sun, making its way from the solar interior up into the atmosphere. Emergence occurs on small-scales in the quiet Sun where magnetic fragments emerge, interact and cancel and on large-scales in active regions where ...
Murray, Michelle J.
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