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Related papers: MHD mode conversion in a stratified atmosphere

200 papers

Transverse magnetohydrodynamic (MHD) waves have been shown to be ubiquitous in the solar atmosphere and can in principle carry sufficient energy to generate and maintain the Sun's million-degree outer atmosphere or corona. However, direct…

Solar and Stellar Astrophysics · Physics 2015-08-19 Takenori J. Okamoto , Patrick Antolin , Bart De Pontieu , Han Uitenbroek , Tom Van Doorsselaere , Takaaki Yokoyama

We present simulations of magneto-acoustic wave propagation in a magnetic, plane-parallel stratified solar model atmosphere, employing the CO5BOLD-code. The tests are carried out for two models of the solar atmosphere, which are similar to…

Solar and Stellar Astrophysics · Physics 2015-05-20 C. Nutto , O. Steiner , M. Roth

MHD waves permeate the solar atmosphere and constitute potential coronal heating agents. Yet, the waves detected so far may be but a small subset of the true existing wave power. Detection is limited by instrumental constraints, but also by…

Solar and Stellar Astrophysics · Physics 2017-02-03 Patrick Antolin , Ineke De Moortel , Tom Van Doorsselaere , Takaaki Yokoyama

Steady-state and transient antiplane dynamic processes in a structured solids consisting of uniform periodic square-cell lattices connected by a lattice layer of different bond stiffnesses and point masses are analyzed. A semi-infinite…

Materials Science · Physics 2011-12-12 Grigory Osharovich , Mark Ayzenberg-Stepanenko

A full 3-dimensional compressible magnetohydrodynamic (MHD) simulation is conducted to investigate the thermal responses of a coronal loop to the dynamic dissipation processes of MHD waves. When the foot points of the loop are randomly and…

Solar and Stellar Astrophysics · Physics 2018-03-14 Takuma Matsumoto

Current models of the solar wind must approximate (or ignore) the small-scale dynamics within the solar atmosphere, however these are likely important in shaping the emerging wave-turbulence spectrum and ultimately heating/accelerating the…

Solar and Stellar Astrophysics · Physics 2022-09-28 Adam J. Finley , Sacha A. Brun , Mats Carlsson , Mikolaj Szydlarski , Viggo Hansteen , Munehito Shoda

A molecular dynamics (MD) simulation was performed to study the propagation of soundwaves in a fluid. Soundwaves are generated by a sinusoidally oscillating wall and annihilated by a locally applied Langevin thermostat near the opposite…

Fluid Dynamics · Physics 2020-10-28 Yuta Asano , Hiroshi Watanabe , Hiroshi Noguchi

Results of forward modelling of acoustic wave propagation in a realistic solar sub-photosphere with two cases of steady horizontal flows are presented and analysed by the means of local helioseismology. The simulations are based on fully…

Astrophysics · Physics 2009-11-13 S. Shelyag , R. Erdelyi , M. J. Thompson

Recent observations of reflected propagating and standing slow-mode waves in hot flaring coronal loops have spurred our investigation into their underlying excitation and damping mechanisms. To understand these processes, we conduct 2.5D…

Solar and Stellar Astrophysics · Physics 2024-04-01 Tongjiang Wang , Leon Ofman , Stephen J. Bradshaw

We investigate the difference in the spatial distribution of the energy input for parametrizations of different mechanisms to heat the corona of the Sun and possible impacts on the coronal emission. We use a 3D MHD model of a solar active…

Solar and Stellar Astrophysics · Physics 2015-06-15 T. van Wettum , S. Bingert , H. Peter

We investigate the propagation of MHD waves in a homogenous, magnetized plasma in a weakly stratified atmosphere, representing hot coronal loops. In most of earlier studies a time-independent equilibrium is considered. Here we abandon this…

Solar and Stellar Astrophysics · Physics 2015-05-20 R. Erdelyi , K. S. Al-Ghafri , R. J. Morton

A simple collisional three-component plasma model consisting of electrons, ions, and neutrals with arbitrary collision frequencies and dynamic time scales is considered. It is shown that the usual MHD-approach dealing with magnetic field…

Solar and Stellar Astrophysics · Physics 2014-02-20 Anatoly K. Nekrasov

The MHD slow mode wave has application to coronal seismology, MHD turbulence, and the solar wind where it can be produced by parametric instabilities. We consider analytically how a drifting ion species (e.g. He$^{++}$) affects the linear…

Space Physics · Physics 2015-06-19 Joseph V. Hollweg , Daniel Verscharen , Benjamin D. G. Chandran

Nonlinear evolution of circularly polarized Alfv\'en waves are discussed by using the recently developed Vlasov-MHD code, which is a generalized Landau-fluid model. The numerical results indicate that as far as the nonlinearity in the…

Solar and Stellar Astrophysics · Physics 2009-10-06 Y. Nariyuki , T. Umeda , T. Kumashiro , T. Hada

Alfven waves are considered to be viable transporters of the non-thermal energy required to heat the Sun's quiescent atmosphere. An abundance of recent observations, from state-of-the-art facilities, have reported the existence of Alfven…

Solar and Stellar Astrophysics · Physics 2015-06-11 Mihalis Mathioudakis , David Jess , Robertus Erdelyi

In the stably stratified ocean, small-scale turbulence is important for vertical exchange and hence for the mixing of water masses and suspended matter. To observationally study turbulent motions and the buoyancy- and shear-generators…

Atmospheric and Oceanic Physics · Physics 2022-09-23 Hans van Haren

Plasma ions heating (especially minor heavy ions preferential heating) in fast solar wind and solar corona is an open question in space physics. However, Alfv\'en waves have been always considered as a candidate of energy source for corona…

Plasma Physics · Physics 2021-08-17 Peng He

The nature of fast magnetoacoustic and Alfv\'en waves is investigated in a zero $\beta$ plasma. This gives an indication of wave propagation in the low $\beta$ solar corona. It is found that for a two-dimensional null point, the fast wave…

Astrophysics · Physics 2009-06-25 J. A. McLaughlin , A. W. Hood

The limitations of Hall MHD as a model for turbulence in weakly collisional plasmas are explored using quantitative comparisons to Vlasov-Maxwell kinetic theory over a wide range of parameter space. The validity of Hall MHD in the cold ion…

Solar and Stellar Astrophysics · Physics 2020-01-29 Gregory G. Howes

The evolutionarity conditions for the MHD shock waves are considered within the framework of the 8-moment approximation for collisionless plasma with heat fluxes. In the general case, evolutionarity diagrams are obtained depending on the…

Plasma Physics · Physics 2024-01-30 V . D. Kuznetsov , A. I. Osin