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Magnetic flux tubes in the solar corona support a rich variety of transverse oscillations, which are theoretically interpreted as magnetohydrodynamic (MHD) modes with a fast and/or Alfv\'enic character. In the standard flux tube model made…

Solar and Stellar Astrophysics · Physics 2024-12-13 Roberto Soler , Andrew Hillier

The global ideal kink equation, for cylindrical geometry and zero beta, is simplified in the high poloidal mode number limit and used to determine the tearing stability parameter, $\Delta^\prime$. In the presence of a steep monotonic…

Plasma Physics · Physics 2015-06-23 J. W. Connor , R. J. Hastie , I. Pusztai , P. J. Catto , M. Barnes

In this work the dynamic magnetic field within a tearing-unstable three-dimensional (3D) current sheet about a magnetic null point is described in detail. We focus on the evolution of the magnetic null points and flux ropes that are formed…

Plasma Physics · Physics 2015-06-22 P. F. Wyper , D. I Pontin

We investigate the evolution of NOAA Active Region 11817 during 2013 August 10--12, when it developed a complex field configuration and produced four confined, followed by two eruptive, flares. These C-and-above flares are all associated…

Solar and Stellar Astrophysics · Physics 2016-02-22 Rui Liu , Bernhard Kliem , Viacheslav S. Titov , Jun Chen , Yuming Wang , Haimin Wang , Chang Liu , Yan Xu , Thomas Wiegelmann

Recent observations have demonstrated the capability of mapping the solar coronal magnetic field using the technique of coronal seismology based on the ubiquitous propagating Alfvenic/kink waves through imaging spectroscopy. We established…

Solar and Stellar Astrophysics · Physics 2024-11-14 Yuhang Gao , Hui Tian , Tom Van Doorsselaere , Zihao Yang , Mingzhe Guo , Konstantinos Karampelas

We present evidence that a magnetic flux rope was formed before a coronal mass ejection (CME) and its associated long-duration flare during a pair of preceding confined eruptions and associated impulsive flares in a compound event in NOAA…

Solar and Stellar Astrophysics · Physics 2021-03-17 Bernhard Kliem , Jeongwoo Lee , Rui Liu , Stephen M. White , Chang Liu , Satoshi Masuda

The collective transverse coronal loop oscillations seem to be detected in the observational studies. In this regard, Luna et al. (2009, ApJ, 692, 1582) modeled the collective kinklike normal modes of several cylindrical loops system using…

Solar and Stellar Astrophysics · Physics 2019-09-02 Narges Fathalian , Hossein Safari

The Parker or field line tangling model of coronal heating is studied comprehensively via long-time high-resolution simulations of the dynamics of a coronal loop in cartesian geometry within the framework of reduced magnetohydrodynamics…

Astrophysics · Physics 2009-12-06 A. F. Rappazzo , M. Velli , G. Einaudi , R. B. Dahlburg

In this work, the development of two-dimensional current sheets with respect to tearing-modes, in collisionless plasmas with a strong guide field, is analysed. During their non-linear evolution, these thin current sheets can become unstable…

Plasma Physics · Physics 2025-03-04 C. Granier , R. Numata , D. Borgogno , E. Tassi , D. Grasso

Erupting magnetic flux ropes (MFRs) play a crucial role in producing solar flares. However, the formation of erupting MFRs in complex coronal magnetic configurations and their subsequent evolution in the flaring events are not fully…

Solar and Stellar Astrophysics · Physics 2023-08-30 Avijeet Prasad , Sanjay Kumar , Alphonse C. Sterling , Ronald L. Moore , Guillaume Aulanier , R. Bhattacharyya , Qiang Hu

Filament eruptions and coronal mass ejections are physical phenomena related to magnetic flux ropes carrying electric current. A magnetic flux rope is a key structure for solar eruptions, and when it carries a southward magnetic field…

Solar and Stellar Astrophysics · Physics 2024-08-14 Brigitte Schmieder , Jinhan Guo , Stefaan Poedts

Coronal magnetic flux ropes are closely related to large-scale solar activities. Using a 2.5-dimensional time-dependent ideal magnetohydrodynamic (MHD) model in Cartesian coordinates, we carry out numerical simulations to investigate the…

Solar and Stellar Astrophysics · Physics 2017-12-27 Quanhao Zhang , Yuming Wang , Youqiu Hu , Rui Liu , Kai Liu , Jiajia Liu

We propose a catastrophic magnetospheric model for magnetar precursors and their successive giant flares. Axisymmetric models of the magnetosphere, which contain both a helically twisted flux rope and a current sheet, are established based…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Cong Yu , Lei Huang

We simulate transverse oscillations in radiatively cooling coronal loops and forward-model their spectroscopic and imaging signatures, paying attention to the influence of background emission. The transverse oscillations are driven at one…

Solar and Stellar Astrophysics · Physics 2021-12-01 Mijie Shi , Tom Van Doorsselaere , Patrick Antolin , Bo Li

Using numerical simulations, we study the formation and dynamics of post-flare loops in a local region of the solar atmosphere. The MHD equations rule the post-flare structures' dynamic evolution, including space-dependent magnetic…

Solar and Stellar Astrophysics · Physics 2024-02-15 Mauricio González-Servín , J. J. González-Avilés

Previous studies have found that coronal loops have a nearly uniform thickness, which seems to disagree with the characteristic expansion of active region magnetic fields. This is one of the most intriguing enigmas in solar physics. We here…

Astrophysics · Physics 2009-11-13 M. C. Lopez Fuentes , J. A. Klimchuk , P. Demoulin

The most promising mechanism acting towards damping the kink oscillations of coronal loops is resonant absorption. In this context most of previous studies neglected the effect of the obvious equilibrium flow along magnetic field lines. The…

Solar and Stellar Astrophysics · Physics 2015-05-14 J. Terradas , M. Goossens , I. Ballai

Solar coronal mass ejections are the most energetic events in the Solar System. In their standard formation model, a magnetic flux rope builds up into a coronal mass ejection through magnetic reconnection that continually converts…

Solar and Stellar Astrophysics · Physics 2023-05-08 Tingyu Gou , Rui Liu , Astrid M. Veronig , Bin Zhuang , Ting Li , Wensi Wang , Mengjiao Xu , Yuming Wang

In this paper we present a topological magnetic field investigation of seven two-ribbon flares in sigmoidal active regions observed with Hinode, STEREO, and SDO. We first derive the 3D coronal magnetic field structure of all regions using…

Solar and Stellar Astrophysics · Physics 2015-09-16 A. Savcheva , E. Pariat , S. McKillop , P. McCauley , E. Hanson , Y. Su , E. Werner , E. E. DeLuca

We consider the potential magnetic field associated with a helical electric line current flow, idealizing the near-potential coronal field within which a highly localized twisted current structure is embedded. It is found that this field…

Astrophysics · Physics 2011-02-11 G. J. D. Petrie
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