Results 31 to 40 of about 6,168 (304)
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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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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Formation of magnetic flux tubes in cylindrical wedge geometry [PDF]
, 2012 Three-dimensional (3D) MHD numerical simulations have not been able to demonstrate convincingly the spontaneous formation of large vertical flux tubes.
Hurlburt, Neal +8 more
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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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Observational signatures of waves and flows in the solar corona [PDF]
, 2015 DM acknowledges support of a Royal Society University Research Fellowship and a KU Leuven Research Council senior research fellowship (SF/12/008). The research leading to these results has also received funding from the European Commission Seventh ...
Antolin, Patrick +3 more
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Unveiling the Mechanism for the Rapid Acceleration Phase in a Solar Eruption
The Astrophysical Journal Letters, 2023 Two major mechanisms have been proposed to drive the solar eruptions: the ideal magnetohydrodynamic instability and the resistive magnetic reconnection. Due to the close coupling and synchronicity of the two mechanisms, it is difficult to identify their ...
Ze Zhong +4 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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Photospheric high-frequency acoustic power excess in sunspot umbra: signature of magneto-acoustic modes [PDF]
, 2013 We present observational evidence for the presence of MHD (magnetohydrodynamic) waves in the solar photosphere deduced from SOHO/MDI (Solar and Heliospheric Observatory/Michelson Doppler Imager) Dopplergram velocity observations.
Shelyag, S. +14 more
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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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