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Related papers: Phase mixing of nonlinear Alfven waves

200 papers

One of the proposed damping mechanisms of coronal (transverse) loop oscillations in the kink-mode is resonant absorption as a result of the Alfven speed variation at the outer boundary of coronal loops. Analytical expressions for the period…

A model for element abundance fractionation between the solar chromosphere and corona is further developed. The ponderomotive force due to Alfven waves propagating through, or reflecting from the chromosphere in solar conditions generally…

Solar and Stellar Astrophysics · Physics 2015-05-30 J. Martin Laming

It has been shown in a previous work that torsional Alfv\'en waves can drive turbulence in nonuniform coronal loops with a purely axial magnetic field. Here we explore the role of the magnetic twist. We model a coronal loop as a…

Solar and Stellar Astrophysics · Physics 2022-09-21 Sergio Díaz-Suárez , Roberto Soler

Context. We diagnose the properties of the plume and interplume regions in a polar coronal hole and the role of waves in the acceleration of the solar wind. Aims. We attempt to detect whether Alfven waves are present in the polar coronal…

Solar and Stellar Astrophysics · Physics 2015-05-13 D. Banerjee , D. Perez-Suarez , J. G. Doyle

Braginskii MHD provides a more accurate description of many plasma environments than classical MHD since it actively treats the stress tensor using a closure derived from physical principles. Stress tensor effects nonetheless remain…

Solar and Stellar Astrophysics · Physics 2023-03-21 Alexander J. B. Russell

Standing slow-mode waves have been recently observed in flaring loops by the Atmospheric Imaging Assembly (AIA) of the Solar Dynamics Observatory (SDO). By means of the coronal seismology technique transport coefficients in hot ($\sim$10…

Solar and Stellar Astrophysics · Physics 2018-07-04 Tongjiang Wang , Leon Ofman , Xudong Sun , Sami K Solanki , Joseph M Davila

Alfv\'en waves propagate in electrically conducting fluids in the presence of a magnetic field. Their reflection properties depend on the ratio between the kinematic viscosity and the magnetic diffusivity of the fluid, also known as the…

Geophysics · Physics 2012-10-17 Nathanaël Schaeffer , Dominique Jault , Philippe Cardin , Marie Drouard

We use 2.5-D electromagnetic particle-in-cell simulation code to investigate the acceleration of electrons in solar coronal holes through the interaction of Alfv\'en waves with an interplume region. The interplume is modeled by a cavity…

Space Physics · Physics 2019-04-30 Khalil Daiffallah , Fabrice Mottez

The linear theory of shock acceleration predicts the maximum particle energy to be limited only by the acceleration time and the size of the shock. We study the combined effect of acceleration nonlinearity (shock modification by accelerated…

Astrophysics · Physics 2007-05-23 M. A. Malkov , P. H. Diamond , T. W. Jones

The overshooting convective motions in the solar photosphere are frequently proposed as the source for the excitation of Alfv\'en waves. However, the photosphere is a) very weakly ionized, and, b) the dynamics of the plasma particles in…

Astrophysics · Physics 2009-11-13 J. Vranjes , S. Poedts , B. P. Pandey , B. De Pontieu

Particle-In-Cell (kinetic) simulations of shear Alfv\'en wave interaction with one dimensional, across the uniform magnetic field, density inhomogeneity (phase mixing) in collisionless plasma were performed for the first time. As a result a…

Astrophysics · Physics 2009-11-10 David Tsiklauri , Jun-Ichi Sakai , Shinji Saito

Observations of molecular clouds show the existence of starless, dense cores, threaded by magnetic fields. Observed line widths indicate these dense condensates to be embedded in a supersonically turbulent environment. Under these…

Astrophysics · Physics 2009-11-10 Doris Folini , Jean Heyvaerts , Rolf Walder

Analyses of the widths and shifts of optically thin emission lines in the ultraviolet spectrum of the active dwarf Epsilon Eri (K2 V) are presented. The spectra were obtained using the Space Telescope Imaging Spectrograph on the Hubble…

Astrophysics · Physics 2008-11-26 S. A. Sim , C. Jordan

Ground observatory and satellite-based determinations of temporal variations in the geomagnetic field probe a decadal to annual time scale range where Earth's core slow, inertialess convective motions and rapidly propagating,…

Geophysics · Physics 2021-02-15 Julien Aubert , Nicolas Gillet

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

The solar atmosphere is structured and inhomogeneous both horizontally and vertically. The omnipresence of coronal magnetic loops implies gradients of the equilibrium plasma quantities like the density, magnetic field and temperature. These…

Solar and Stellar Astrophysics · Physics 2010-07-30 J. Vranjes , S. Poedts

The presence and nature of low-frequency (0.1-10~mHz) Alfv\'enic waves in the corona has been established over the last decade, with many of these results coming from coronagraphic observations of the infrared Fe XIII line. The Cryo-NIRSP…

Solar and Stellar Astrophysics · Physics 2025-02-21 Richard J. Morton , Momchil Molnar , Steven R. Cranmer , Thomas A. Schad

We perform 2.5D hybrid simulations with massless fluid electrons and kinetic particle-in-cell ions to study the temporal evolution of ion temperatures, temperature anisotropies and velocity distribution functions in relation to the…

Plasma Physics · Physics 2015-06-18 Y. G. Maneva , Adolfo F. Viñas , Pablo S. Moya , R. Wicks , S. Poedts

Alfv\'enic waves are considered a key contributor to the energy flux that powers the Sun's corona, with theoretical models demonstrating their potential to explain coronal EUV and X-ray emission and the acceleration of the solar wind.…

Solar and Stellar Astrophysics · Physics 2025-05-14 R. J. Morton , R. Soler

The parametric decay of finite-size Alfv\'en waves in nonperiodic low-beta plasmas is investigated using one-dimensional hybrid simulations. Compared with the usual small periodic system, a wave packet in a large system under the absorption…

Plasma Physics · Physics 2021-10-28 Feiyu Li , Xiangrong Fu , Seth Dorfman