Results 21 to 30 of about 5,382 (223)
Measurements of Coronal Magnetic Field Strengths in Solar Active Region Loops [PDF]
The Astrophysical Journal Letters, 2021 Abstract The characteristic electron densities, temperatures, and thermal distributions of 1 MK active region loops are now fairly well established, but their coronal magnetic field strengths remain undetermined. Here we present measurements from a sample of coronal loops observed by the Extreme-ultraviolet Imaging Spectrometer on Hinode.
David H. Brooks +2 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
doaj +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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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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Modeling Nonpotential Magnetic Fields in Solar Active Regions
The Astrophysical Journal, 2008 Electric currents are present in the coronae above solar active regions, producing nonpotential magnetic fields that can be approximated as nonlinear force-free fields (NLFFFs). In this paper NLFFF models for two active regions observed in 2002 June are presented.
M. G. Bobra +2 more
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Magnetic field inclination and atmospheric oscillations above solar active regions [PDF]
Monthly Notices of the Royal Astronomical Society, 2006 Recent observational evidence for magnetic field direction effects on helioseismic signals in sunspot penumbrae is suggestive of magnetohydrodynamic (MHD) mode conversion occurring at lower levels. This possibility is explored using wave mechanical and ray theory in a model of the Sun's surface layers permeated by uniform inclined magnetic field. It is
H. Schunker, P. S. Cally
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Current helicity and magnetic field anisotropy in solar active regions [PDF]
Monthly Notices of the Royal Astronomical Society, 2015 MNRAS ...
Xu, H. +5 more
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Advanced Functional Materials, EarlyView.This review systematically highlights the latest achievements in mixed‐valence states relevant to hydrogen and oxygen evolution reactions, providing essential insights into future directions and methods for large‐scale practical implementation. This critical review is expected to provide an overview of recent advancements in diverse valence‐state metal
Jitendra N. Tiwari +4 more
wiley +1 more source
Temporal Evolution of Sunspot Groups and Increase in the Open Flux during Solar Maximum in Cycle 24
The Astrophysical JournalThe evolution of the global solar magnetic field directly impacts the interplanetary magnetic field (IMF). During the solar maximum of Cycle 24, the monthly averaged IMF strength doubled over five Carrington rotations (CRs) in late 2014.
Minami Yoshida +3 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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