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Related papers: A data-driven MHD model of the weakly-ionized chro…

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In the context of the solar atmosphere, we re-examine the role of of neutral and ionized species in dissipating the ordered energy of intermediate-mode MHD waves into heat. We solve conservation equations for the hydrodynamics and for…

Solar and Stellar Astrophysics · Physics 2020-09-09 Philip G. Judge

The solar atmosphere was traditionally represented with a simple one-dimensional model. Over the past few decades, this paradigm shifted for the chromosphere and corona that constitute the outer atmosphere, which is now considered a dynamic…

We present the first magnetohydrodynamic model of the stellar chromospheric heating and acceleration of the outer atmospheres of cool evolved stars, using alpha Tau as a case study. We used a 1.5D MHD code with a generalized Ohm's law that…

Solar and Stellar Astrophysics · Physics 2014-09-15 V. S. Airapetian , J. E. Leake , K. G. Carpenter

Well-known analytical results dealing with ion cyclotron and drift waves and which follow from the kinetic theory are used and the dispersion equation, which describes coupled two modes, is solved numerically. The numerical results obtained…

Astrophysics · Physics 2009-11-13 J. Vranjes , S. Poedts

We aim to identify the physical processes which occur in the magnetic network of the chromosphere and which contribute to its dynamics and heating. Specifically, we study the propagation of transverse (kink) MHD waves which are impulsively…

Astrophysics · Physics 2009-11-10 S. S. Hasan , P. Ulmschneider

We show that the coronal heating and the acceleration of the fast solar wind in the coronal holes are natural consequence of the footpoint fluctuations of the magnetic fields at the photosphere by one-dimensional, time-dependent, and…

Astrophysics · Physics 2007-05-23 Takeru K. Suzuki , Shu-ichiro Inutsuka

Dissipation of magnetohydrodynamic (MHD) wave energy has been proposed as a viable heating mechanism in the solar chromospheric plasma. Here, we use a simplified one-dimensional model of the chromosphere to theoretically investigate the…

Solar and Stellar Astrophysics · Physics 2015-09-23 Roberto Soler , Marc Carbonell , Jose Luis Ballester

An analytical and numerical treatment is given of a constrained version of the tectonics model developed by Priest, Heyvaerts, & Title [2002]. We begin with an initial uniform magnetic field ${\bf B} = B_0 \hat{\bf z}$ that is line-tied at…

Solar and Stellar Astrophysics · Physics 2011-09-07 C. S. Ng , A. Bhattacharjee

We numerically studied magnetic reconnection in a high $\beta$ hydrogen-helium plasma at different altitudes from the photosphere to the upper chromosphere. The time dependent ionization degrees were included to get more realistic…

Solar and Stellar Astrophysics · Physics 2023-11-30 Abdullah Zafar , Lei Ni , Jun Lin , Udo Ziegler

We investigate the spatial and temporal evolution of the heating of the corona of a cool star such as our Sun in a three-dimensional magneto-hydrodynamic (3D MHD) model. We solve the 3D MHD problem numerically in a box representing part of…

Space Physics · Physics 2015-05-27 Sven Bingert , Hardi Peter

We report on a detailed radiative transfer modeling of the observed scattering polarization in the H-alpha line, which allows us to infer quantitative information on the magnetization of the quiet solar chromosphere. Our analysis suggests…

Solar and Stellar Astrophysics · Physics 2015-05-18 Jiri Stepan , Javier Trujillo Bueno

We studied the acceleration mechanisms of chromospheric jets associated with emerging flux using a two dimensional magnetohydrodynamic (MHD) simulation. We found that slow mode shock waves generated by magnetic reconnection in the…

Solar and Stellar Astrophysics · Physics 2015-06-12 Shinsuke Takasao , Hiroaki Isobe , Kazunari Shibata

We model a coronal loop as a three-dimensional magnetic cylinder in a realistic solar atmosphere that extends from the chromosphere to the corona. Kink oscillations, believed ubiquitous in the solar corona, are launched in the loop. Heating…

Solar and Stellar Astrophysics · Physics 2023-05-31 Mingzhe Guo , Timothy Duckenfield , Tom Van Doorsselaere , Konstantinos Karampelas , Gabriel Pelouze , Yuhang gao

A simplified non-linear numerical model for the development of incompressible magnetohydrodynamics (MHD) in the presence of a strong magnetic field B0 and stratification, nicknamed Shell-Atm, is presented. In planes orthogonal to the mean…

Astrophysics · Physics 2011-02-11 E. Buchlin , M. Velli

The dynamical coupling between the solar chromospheric plasma and magnetic field is investigated by numerically solving a fully self-consistent, two-dimensional initial-value problem for the nonlinear collisional MHD equations including…

Solar and Stellar Astrophysics · Physics 2015-12-09 L. M. Alekseeva , S. P. Kshevetskii

The question why the solar corona is much hotter than the visible solar surface still puzzles solar researchers. Most theories of the coronal heating involve a tight coupling between the coronal magnetic field and the associated thermal…

Solar and Stellar Astrophysics · Physics 2021-03-17 Gregory D. Fleishman , Sergey A. Anfinogentov , Alexey G. Stupishin , Alexey A. Kuznetsov , Gelu M. Nita

We report preliminary results from a series of numerical simulations of the reduced magnetohydrodynamic equations, used to describe the dynamics of magnetic loops in active regions of the solar corona. A stationary velocity field is applied…

Astrophysics · Physics 2009-10-31 Pablo Dmitruk , Daniel Gomez

Static distributions of temperature and wind velocity at the transition region are calculated within the framework of magnetohydrodynamics (MHD) of completely ionized hydrogen plasma. The numerical solution of the derived equations gives…

Solar flares and plasma eruptions are sudden releases of magnetic energy stored in the plasma atmosphere. To understand the physical mechanisms governing their occurrences, three-dimensional magnetic fields from the photosphere up to the…

Solar and Stellar Astrophysics · Physics 2021-03-24 Takafumi Kaneko , Sung-Hong Park , Kanya Kusano

The formation of shocks within the solar atmosphere remains one of the few observable signatures of energy dissipation arising from the plethora of magnetohydrodynamic waves generated close to the solar surface. Active region observations…