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Related papers: Numerical simulations of conversion to Alfven wave…

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We perform three dimensional (3D) ideal magnetohydrodynamic (MHD) simulations to study the parametric decay instability of Alfven waves in turbulent plasmas and explore its possible applications in the solar wind. We find that, over a broad…

Space Physics · Physics 2017-06-16 Mijie Shi , Hui Li , Chijie Xiao , Xiaogang Wang

The photospheric temperature minimum in the Sun and solar-like stars is very weakly ionized, with ionization fraction $f$ as low as $10^{-4}$. In galactic star forming regions, $f$ can be $10^{-10}$ or lower. Under these circumstances, the…

Solar and Stellar Astrophysics · Physics 2015-12-02 Paul S. Cally , Elena Khomenko

In a magnetised plasma on scales well above ion kinetic scales, any constant-magnitude magnetic field, accompanied by parallel Alfv\'enic flows, forms a nonlinear solution in an isobaric, constant-density background. These structures, which…

Solar and Stellar Astrophysics · Physics 2022-09-01 Jonathan Squire , Alfred Mallet

We have developed 3D, compressible, non-linear radiative MHD simulations to study the influence of the magnetic field of various strength and geometry on the turbulent convective cells and on the excitation mechanisms of the acoustic…

Solar and Stellar Astrophysics · Physics 2009-01-29 Irina Kitiashvili , Laetitia Jacoutot , Alexander Kosovichev , Alan Wray , Nagi Mansour

Nonlinear coupling between 3-minute oscillations and Alfven waves in the solar lower atmosphere is studied. 3-minute oscillations are considered as acoustic waves trapped in a chromospheric cavity and oscillating along transversally…

Astrophysics · Physics 2015-06-24 D. Kuridze , T. V. Zaqarashvili

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

Wave propagation in magnetically structured atmospheres is a thoroughly studied, yet practically inexhaustible well of investigations in the field of solar magneto-seismology. A simple but powerful example is the examination of wave…

Solar and Stellar Astrophysics · Physics 2020-04-14 Noémi Kinga Zsámberger , Róbert Erdélyi

Strongly stratified hydromagnetic turbulence has previously been found to produce magnetic flux concentrations if the domain is large enough compared with the size of turbulent eddies. Mean-field simulations (MFS) using parameterizations of…

Solar and Stellar Astrophysics · Physics 2014-02-06 A. Brandenburg , O. Gressel , S. Jabbari , N. Kleeorin , I. Rogachevskii

We use 2D numerical simulations and eikonal approximation, to study properties of MHD waves traveling below the solar surface through the magnetic structure of sunspots. We consider a series of magnetostatic models of sunspots of different…

Astrophysics · Physics 2011-02-11 E. Khomenko , A. Kosovichev , M. Collados , K. Parchevsky , V. Olshevsky

We present a model for FRBs where a large amplitude Alfven wave packet is launched by a disturbance near the surface of a magnetar, and a substantial fraction of the wave energy is converted to coherent radio waves at a distance of a few…

High Energy Astrophysical Phenomena · Physics 2020-04-29 Pawan Kumar , Z. Bosnjak

Alfv\'en waves are responsible for the transfer of magnetic energy in the magnetized plasma. They are involved in heating solar atmosphere and driving solar wind through various nonlinear processes. Since the magnetic field configurations…

Solar and Stellar Astrophysics · Physics 2020-08-04 Takahito Sakaue , Kazunari Shibata

We demonstrate that in highly magnetized pair plasmas, nonlinear Alfven waves with wave-number $k \leq k_0 = \omega_p^2 /(\delta \omega_B)$ ($\delta =( \delta B)/B_0$ are relative fluctuations of the magnetic field) experience powerful…

High Energy Astrophysical Phenomena · Physics 2026-05-05 Maxim Lyutikov

Numerical simulations of weakly magnetized and strongly magnetized relativistic jets embedded in a weakly magnetized and strongly magnetized stationary or weakly relativistic (v = c/2) sheath have been performed. A magnetic field parallel…

Astrophysics · Physics 2009-11-13 Yosuke Mizuno , Philip Hardee , Ken-Ichi Nishikawa

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

The problem of solar chromospheric heating remains a challenging one with wider implications for stellar physics. Several studies in the recent past have shown that small-scale inclined magnetic field elements channel copious amount of…

Solar and Stellar Astrophysics · Physics 2018-12-14 S. P. Rajaguru , C. R. Sangeetha , Durgesh Tripathi

Sunspots are prominent manifestations of solar magnetoconvection and imaging their subsurface structure is an outstanding problem of wide physical importance. Travel times of seismic waves that propagate through these structures are…

Solar and Stellar Astrophysics · Physics 2015-06-05 Shravan Hanasoge , Aaron Birch , Laurent Gizon , Jeroen Tromp

Context: Supersonic nonthermal motions in molecular clouds are often interpreted as long-lived magnetohydrodynamic (MHD) waves. The propagation and amplitude of these waves is affected by local physical characteristics, most importantly the…

Astrophysics of Galaxies · Physics 2015-06-05 C. Pinto , A. Verdini , D. Galli , M. Velli

We study the evolution of non-linear circularly polarised Alfven waves by solving numerically the time-dependent equations of magnetohydrodynamics (MHD) in one dimension. We examine the behaviour of the waves and find that different…

Astrophysics · Physics 2009-11-10 Rim Turkmani , Ulf Torkelsson

A fast Alfv\'en wave with finite amplitude is shown to grow by a stimulated emission process that we propose for exploitation in toroidal magnetically confined fusion plasmas. Stimulated emission occurs while the wave propagates inward…

Plasma Physics · Physics 2017-05-10 J W S Cook , R O Dendy , S C Chapman

In the magnetosphere of a rotating black hole, an inner Alfven critical surface (IACS) must be crossed by inflowing plasma. Inside the IACS, Alfven waves are inward directed toward the black hole. The majority of the proper volume of the…

High Energy Astrophysical Phenomena · Physics 2016-09-19 Brian Punsly , Dinshaw Balsara , Jinho Kim , Sudip Garain