Results 11 to 20 of about 10,569,280 (283)
The evolution of a spot–spot-type solar active region which produced a major solar eruption
Frontiers in Astronomy and Space Sciences, 2023 Solar active regions are the main sources of large solar flares and coronal mass ejections. It is found that the active regions producing large eruptions usually show compact, highly sheared polarity inversion lines.
Lijuan Liu, Lijuan Liu, Lijuan Liu
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Magnetic Fields in the Solar Convection Zone
Living Reviews in Solar Physics, 2009 Active regions on the solar surface are generally thought to originate from a strong toroidal magnetic field generated by a deep seated solar dynamo mechanism operating at the base of the solar convection zone.
Yuhong Fan
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Magnetic Fields in the Solar Convection Zone
Living Reviews in Solar Physics, 2004 Recent studies of the dynamic evolution of magnetic flux tubes in the solar convection zone are reviewed with focus on emerging flux tubes responsible for the formation of solar active regions. The current prevailing picture is that active regions on the
Fan Yuhong
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Coronal Currents, Magnetic Fields, and Heating in a Solar Active Region
Astrophysical Journal, 1998 We compare microwave images of a solar active region with state-of-the-art fully nonlinear force-free extrapolations of the photospheric fields in order to study the link between coronal currents and heating of the corona. This extrapolation fully takes into account the nonuniform distribution of electric currents observed in the photosphere and its ...
Zoran Mikić +2 more
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Large Photospheric Doppler Shift in Solar Active Region 12673. I. Field-aligned Flows
The Astrophysical Journal, 2023 Delta ( δ ) sunspots sometimes host fast photospheric flows along the central magnetic polarity inversion line (PIL). Here we study the strong Doppler shift signature in the central penumbral light bridge of solar active region NOAA 12673.
Jiayi Liu +5 more
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Magnetic field variations and seismicity of solar active regions [PDF]
Monthly Notices of the Royal Astronomical Society: Letters, 2009 Abstract Dynamical changes in the solar corona have proven to be very important in inducing seismic waves into the photosphere. Different mechanisms for their generation have been proposed. In this work, we explore the magnetic field forces as plausible mechanisms to generate sunquakes as proposed by Hudson, Fisher & Welsch.
Martinez-Oliveros, J. C., Donea, A. -C.
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On the Origin of the Photospheric Magnetic Field
The Astrophysical Journal, 2022 This article presents results that challenge the paradigms that (1) the convection zone is the source of the radial magnetic field in the photosphere and (2) that coronal currents are neutralized from the perspective of the photosphere.
Peter W. Schuck +3 more
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Characterizing 3D Magnetic Structures in Sunspot Light Bridges
The Astrophysical Journal, 2023 Light bridges (LBs) are narrow structures dividing sunspot umbra, and their role in active region evolution is yet to be explored. We investigated the magnetic structure of the two LBs: a narrow LB (with width ∼810 km) and a considerably wider LB (2475 ...
Ju Jing +5 more
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The solar active region magnetic field and energetics [PDF]
Proceedings of the International Astronomical Union, 2010 AbstractMotivated by increasingly more advanced solar observations, we recently develop a method of coronal magnetic field extrapolation, especially for an active region (sunspot region). Based on a more complex variational principle, the principle of minimum (energy) dissipation rate (MDR), we adopt and solve a more complex equation governing the ...
Qiang Hu +4 more
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The Astrophysical Journal Supplement Series, 2023 It is well accepted that the physical properties obtained from the solar magnetic field observations of active regions (ARs) are related to solar eruptions.
Jingjing Wang +3 more
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