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Related papers: Wave transformations near a coronal magnetic null-…

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We consider the ideal magnetohydrodynamics (MHD) subjected to a strong magnetic field along $x_1$ direction in three-dimensional thin domains $\Omega_\delta=\mathbb{R}^2\times(-\delta,\delta)$ with slip boundary conditions. It is well-known…

Analysis of PDEs · Mathematics 2018-04-02 Li Xu

We present numerical simulations of reduced magnetohydrodynamic (RMHD) turbulence in a magnetic flux tube at the center of a polar coronal hole. The model for the background atmosphere is a solution of the momentum equation, and includes…

Solar and Stellar Astrophysics · Physics 2016-04-27 A. A. van Ballegooijen , M. Asgari-Targhi

Mode conversion in the region where the sound and Alfven speeds are equal is a complex process, which has been studied both analytically and numerically, and has been seen in observations. In order to further the understanding of this…

Astrophysics · Physics 2008-08-04 A. M. Dee McDougall , Alan W. Hood

Magnetohydrodynamic (MHD) waves are ubiquitous in the solar atmosphere. Alfven waves and magneto-sonic waves are particular classes of MHD waves. These wave modes are clearly different and have pure properties in uniform plasmas of infinite…

Solar and Stellar Astrophysics · Physics 2015-06-05 M. Goossens , J. Andries , R. Soler , T. Van Doorsselaere , I. Arregui , J. Terradas

The conversion of fast waves to the Alfven mode in a realistic sunspot atmosphere is studied through three-dimensional numerical simulations. An upward propagating fast acoustic wave is excited in the high-beta region of the model. The new…

Solar and Stellar Astrophysics · Physics 2015-06-11 T. Felipe

Whilst there are observational indications that transverse MHD waves carry enough energy to maintain the thermal structure of the solar corona, it is not clear whether such energy can be efficiently and effectively converted into heating.…

Solar and Stellar Astrophysics · Physics 2019-02-27 Paolo Pagano , Ineke De Moortel

Phase-mixing of Alfv\'en waves in the solar corona has been identified as one possible candidate to explain coronal heating. While this scenario is supported by observations of ubiquitous oscillations in the corona carrying sufficient wave…

Solar and Stellar Astrophysics · Physics 2017-05-17 Paolo Pagano , Ineke De Moortel

In recent years, coronal loops have been the focus of studies related to the damping of different magnetohydrodynamic (MHD) surface waves and their connection with coronal seismology and wave heating. For a better understanding of wave…

Solar and Stellar Astrophysics · Physics 2019-03-06 K. Karampelas , T. Van Doorsselaere , M. Guo

We study the conversion of fast magneto-acoustic waves to Alfven waves by means of 2.5D numerical simulations in a sunspot-like magnetic configuration. A fast, essentially acoustic, wave of a given frequency and wave number is generated…

Solar and Stellar Astrophysics · Physics 2015-06-03 Elena Khomenko , Paul Cally

Aims. We investigate the transfer of energy between a standing kink mode and azimuthal Alfven waves within an expanding flux tube. We consider the process of resonant absorption in a loop with a non-uniform Alfven frequency profile but in…

Solar and Stellar Astrophysics · Physics 2019-11-06 Thomas Howson , Ineke De Moortel , Patrick Antolin , Tom Van Doorsselaere , Andrew Wright

Waves are thought to play a significant role in the heating of the solar atmosphere and the acceleration of the wind. Among the many types of waves observed in the Sun, the so-called p-modes with a 3 mHz frequency peak dominate the lower…

Magnetic fields are key ingredients for heating the solar corona to temperatures of several million Kelvin. A particularly important region with respect to this is the so-called magnetic canopy below the corona, where sound and Alfv\'en…

Solar and Stellar Astrophysics · Physics 2023-01-23 Th. Gundrum , J. Forbriger , Th. Herrmannsdörfer , G. Mamatsashvili , S. Schnauck , F. Stefani , J. Wosnitza

The interaction of a fast magnetoacoustic wave with a magnetic null point is studied in the context of the sympathetic flare phenomenon. Attention is paid to steepening the wave caused by the finite-amplitude effects in a non-uniform plasma…

Solar and Stellar Astrophysics · Physics 2026-05-07 Yu Zhong , Valery M. Nakariakov , Mariana Cécere , Andrea Costa

Identifying the heating mechanisms of the solar corona and the driving mechanisms of solar wind are key challenges in understanding solar physics. A full three-dimensional compressible magnetohydrodynamic (MHD) simulation was conducted to…

Solar and Stellar Astrophysics · Physics 2020-11-25 Takuma Matsumoto

We performed 2.5D magnetohydrodynamic (MHD) simulations showing the propagation of fast-mode MHD waves of different initial amplitudes and their interaction with a coronal hole (CH), using our newly developed numerical code. We find that…

Low-order, non-axisymmetric p-modes (also referred as inertial-acoustic modes) trapped in the inner-most region of hydrodynamic accretion discs around black holes, are plausible candidates for high-frequency quasi-periodic oscillations…

High Energy Astrophysical Phenomena · Physics 2011-01-11 Wen Fu , Dong Lai

We solve numerically the ideal MHD equations with an external gravitational field in 2D in order to study the effects of impulsively generated linear and non-linear Alfv\'en waves into isolated solar arcades and coronal funnels. We analyze…

Solar and Stellar Astrophysics · Physics 2015-09-23 J. J. Gonzalez-Aviles , F. S. Guzman

Planar acoustically dominated magneto\-hydro\-dynamic waves are initiated at the high-$\beta$ base of a simulated 2D isothermal stratified atmosphere with potential magnetic field exhibiting both open and closed field regions as well as…

Solar and Stellar Astrophysics · Physics 2021-06-23 Jamon D. Pennicott , Paul S. Cally

We study the coupling of magneto-acoustic waves to Alven waves using 2.5D numerical simulations. In our experiment, a fast magnetoacoustic wave of a given frequency and wavenumber is generated below the surface. The magnetic field in the…

Solar and Stellar Astrophysics · Physics 2015-05-20 Elena Khomenko , Paul Cally

Context. Waves are ubiquitous in the solar corona and there are indications that they are excited by photospheric p-modes. However, it is unclear how p-modes in coronal loops are converted to sausage modes and transverse (kink) modes, which…

Solar and Stellar Astrophysics · Physics 2019-05-29 Julia M. Riedl , Tom Van Doorsselaere , Irantzu Calvo Santamaria