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Related papers: Time-Dependent Dynamics of the Corona

200 papers

This work analyzes the Hall magnetohydrodynamics (HMHD) and magnetohydrodynamics (MHD) numerical simulations of a flaring solar active region as a testbed while idealizing the coronal Alfv\'en speed to be of two orders of magnitude lesser.…

Solar and Stellar Astrophysics · Physics 2022-02-16 Kamlesh Bora , Ramit Bhattacharyya , Avijeet Prasad , Bhuwan Joshi , Qiang Hu

Numerical MHD simulations of 3D reconnection events in the solar corona have improved enormously over the last few years, not only in resolution, but also in their complexity, enabling more and more realistic modeling. Various ways to…

Solar and Stellar Astrophysics · Physics 2012-11-07 G. Baumann , K. Galsgaard , Å. Nordlund

We present the first model that couples the formation of the corona of a solar active region to a model of the emergence of a sunspot pair. This allows us to study when, where, and why active region loops form, and how they evolve. We use a…

Solar and Stellar Astrophysics · Physics 2014-05-08 F. Chen , H. Peter , S. Bingert , M. C. M. Cheung

Aims. The goal is to employ a 3D magnetohydrodynamics (MHD) model including spectral synthesis to model the corona in an observed solar active region. This will allow us to judge the merits of the coronal heating mechanism built into the 3D…

Solar and Stellar Astrophysics · Physics 2017-09-19 Ph. -A. Bourdin , S. Bingert , H. Peter

The solar corona has been revealed in the past decade to be a highly dynamic nonequilibrium plasma environment. Both the loop-filled coronal base and the extended acceleration region of the solar wind appear to be strongly turbulent, but…

Astrophysics · Physics 2008-11-26 Steven R. Cranmer

We study the formation of coronal jets through numerical simulation of the emergence of a twisted magnetic flux rope into a pre-existing open magnetic field. Reconnection inside the emerging flux rope in addition to that between the…

Solar and Stellar Astrophysics · Physics 2015-06-19 Fang Fang , Yuhong Fan , Scott W. McIntosh

We present a novel global 3-D coronal MHD model called COCONUT, polytropic in its first stage and based on a time-implicit backward Euler scheme. Our model boosts run-time performance in comparison with contemporary MHD-solvers based on…

Solar and Stellar Astrophysics · Physics 2022-08-31 Barbara Perri , Peter Leitner , Michaela Brchnelova , Tinatin Baratashvili , Blazej Kuzma , Fan Zhang , Andrea Lani , Stefaan Poedts

We investigate the timescales of evolution of stellar coronae in response to surface differential rotation and diffusion. To quantify this we study both the formation time and lifetime of a magnetic flux rope in a decaying bipolar active…

Solar and Stellar Astrophysics · Physics 2014-08-11 G. P. S. Gibb , M. M. Jardine , D. H. Mackay

The dynamics of magnetic fields in closed regions of solar and stellar coronae are investigated with a reduced magnetohydrodynamic (MHD) model in the framework of Parker scenario for coronal heating. A novel analysis of reduced MHD…

Solar and Stellar Astrophysics · Physics 2015-12-04 A. F. Rappazzo

By comparing a magneto-frictional model of the low coronal magnetic field to a potential-field source-surface model, we investigate the possible impact of non-potential magnetic structure on empirical solar-wind models. These empirical…

Solar and Stellar Astrophysics · Physics 2015-12-09 S. J. Edwards , A. R. Yeates , F. -X. Bocquet , D. H. Mackay

Solar coronal loops are commonly subject to oscillations. Observations of coronal oscillations are used to infer physical properties of the coronal plasma using coronal seismology. Excitation and evolution of oscillations in coronal loops…

Solar and Stellar Astrophysics · Physics 2021-03-17 P. Kohutova , A. Popovas

We present the application of the data-driven branch of the MURaM code, which follows the evolution of the active region 11640 over 4 days starting from 2012 December 30 at 12:00 UT and reproduces many key coronal extreme-ultraviolet (EUV)…

Solar and Stellar Astrophysics · Physics 2026-05-14 Feng Chen

The Sun is a highly dynamic environment that exhibits dynamic behavior on many different timescales. In particular, coronal holes exhibit temporal and spatial variability. Signatures of these coronal dynamics are inherited by the coronal…

We present numerical simulations in 3D settings where coronal rain phenomena take place in a magnetic configuration of a quadrupolar arcade system. Our simulation is a magnetohydrodynamic simulation including anisotropic thermal conduction,…

Solar and Stellar Astrophysics · Physics 2016-01-20 S. P. Moschou , R. Keppens , C. Xia , X. Fang

This paper reviews the current state of our understanding of high-speed solar wind acceleration in coronal holes. Observations by SOHO, coupled with interplanetary particle measurements going back several decades, have put strong…

Astrophysics · Physics 2007-05-23 Steven R. Cranmer

Observations of surface magnetic fields are now within reach for many stellar types thanks to the development of Zeeman-Doppler Imaging. These observations are extremely useful for constraining rotational evolution models of stars, as well…

Solar and Stellar Astrophysics · Physics 2015-09-24 Victor Réville , Allan Sacha Brun , Antoine Strugarek , Sean P. Matt , Jérôme Bouvier , Colin P. Folsom , Pascal Petit

We present a method of conducting data-driven simulations of solar active regions and flux emergence with the MURaM radiative magnetohydrodynamics (MHD) code. The horizontal electric field derived from the full velocity and magnetic…

Solar and Stellar Astrophysics · Physics 2023-06-14 Feng Chen , Mark C. M. Cheung , Matthias Rempel , Georgios Chintzoglou

Knowledge of the electron density distribution in the solar corona put constraints on the magnetic field configurations for coronal modeling and on initial conditions for solar wind modeling. We work with polarized SOHO/LASCO-C2 images from…

Solar and Stellar Astrophysics · Physics 2015-12-15 Judith de Patoul , Claire Foullon , Pete Riley

We present the results of a set of three-dimensional numerical simulations of magnetic flux emergence from below the photosphere into the corona that include a uniform and horizontal coronal magnetic field mimicking a pre-existing…

Astrophysics · Physics 2009-11-10 K. Galsgaard , F. Moreno-Insertis , V. Archontis , A. Hood

We present simulations modeling closed regions of the solar corona threaded by a strong magnetic field where localized photospheric vortical motions twist the coronal field lines. The linear and nonlinear dynamics are investigated in the…

Solar and Stellar Astrophysics · Physics 2013-06-20 A. F. Rappazzo , M. Velli , G. Einaudi