NONLINEAR DAMPING OF ALFVÉN WAVES IN THE SOLAR CORONA BELOW 1.5 SOLAR RADII

2015 ◽  
Vol 811 (2) ◽  
pp. 88 ◽  
Author(s):  
J. S. Zhao ◽  
Y. Voitenko ◽  
Y. Guo ◽  
J. T. Su ◽  
D. J. Wu
Keyword(s):  
Solar Corona ◽  
Nonlinear Damping ◽  
Alfven Waves ◽  
Alfvén Waves

Generation of harmonic Alfvén waves and its implications to heavy ion heating in the solar corona: Hybrid simulations

2020 ◽  
Vol 27 (1) ◽  
pp. 012901
Author(s):  
Jiansheng Yao ◽  
Quanming Lu ◽  
Xinliang Gao ◽  
Jian Zheng ◽  
Huayue Chen ◽  
...  
Keyword(s):  
Solar Corona ◽  
Heavy Ion ◽  
Alfven Waves ◽  
Alfvén Waves ◽  
Ion Heating ◽  
Hybrid Simulations

Nonlinear Landau Damping of Alfvén Waves in a High β Plasma

1982 ◽  
Vol 37 (8) ◽  
pp. 809-815 ◽  
Author(s):  
Heinrich J. Völk ◽  
Catherine J. Cesarsky
Keyword(s):  
Wave Length ◽  
Wave Spectrum ◽  
Nonlinear Damping ◽  
Alfven Waves ◽  
Alfvén Waves ◽  
Propagating Waves ◽  
Damping Rate ◽  
Nonlinear Landau Damping ◽  
The Waves ◽  
The Magnetic Field

A study is made of the nonlinear damping of parallel propagating Alfvén waves in a high β plasma. Two circularly polarized parallel propagating waves give rise to a beat wave, which in general contains both a longitudinal electric field component and a longitudinal gradient in the magnetic field strength. The wave damping is due to the interactions of thermal particles with these fields. If the amplitudes of the waves are low, a given wave (ω1, k1) is damped by the presence of all longer wavelength waves; thus, if the amplitudes of the waves in the wave spectrum increase with wave length, the effect of the longest waves is dominant.However, when the amplitude of the waves is sufficiently high, the particles are trapped in the wave packets, and the damping rate may be considerably reduced. We calculate the induced electrostatic field, and examine the trapping of thermal particles in a pair of waves. Finally, we give examples of modified damping rates of a wave in the presence of a spectrum of waves, and show that, when the trapping is effective, the waves are mostly damped by their interactions with waves of comparable wavelengths

Magnetohydrodynamic plasma instability driven by Alfvén waves excited by cosmic rays

1984 ◽  
Vol 31 (2) ◽  
pp. 275-299 ◽  
Author(s):  
J. F. McKenzie ◽  
G. M. Webb
Keyword(s):  
Cosmic Rays ◽  
Thermal Plasma ◽  
Cosmic Ray ◽  
Nonlinear Damping ◽  
Alfven Waves ◽  
Alfven Wave ◽  
Shock Acceleration ◽  
Alfvén Waves ◽  
Wave Growth ◽  
Streaming Instability

Hydrodynamical equations describing the mutual interaction of cosmic rays, thermal plasma, magnetic field and Alfvén waves scattering the cosmic rays used in cosmic ray shock acceleration theory (e.g. McKenzie & Völk 1982; Drury 1983; Webb 1983) are analysed for long-wavelength linear compressive instabilities. The Alfvén wave field may contain a pre-existing component as well as a component excited by the cosmic ray streaming instability. In the case of no Alfvén wave damping, adiabatic wave growth and Alfvén wave generation by the cosmic ray streaming instability, it is found that the backward propagating slow magneto-acoustic mode is driven convectively unstable by the pressure of the self-excited Alfvén waves, provided the thermal plasmaβis sufficiently large. The equations are also analysed for the case where the Alfvén wave growth is balanced by some nonlinear damping mechanisms. In the latter case both the forward and backward propagating slow magneto-acoustic modes may be driven unstable if the plasmaβis sufficiently small. The conditions under which the instabilities occur are delineated, and sample calculations of growth rates given. Possible applications of the instabilities to astrophysical situations are briefly discussed.

The problem of phase mixed shear Alfvén waves in the solar corona revisited

2008 ◽  
Vol 329 (8) ◽  
pp. 780-785 ◽  
Author(s):  
G. Mocanu ◽  
A. Marcu ◽  
I. Ballai ◽  
B. Orza
Keyword(s):  
Solar Corona ◽  
Alfven Waves ◽  
Alfvén Waves ◽  
Shear Alfven Waves

Landau damped kinetic Alfvén waves and coronal heating

2009 ◽  
Vol 76 (2) ◽  
pp. 239-246 ◽  
Author(s):  
R. P. SHARMA ◽  
SACHIN KUMAR
Keyword(s):  
Solar Corona ◽  
Initial Conditions ◽  
Planck Equation ◽  
Alfven Waves ◽  
Coronal Heating ◽  
Landau Damping ◽  
Alfvén Waves ◽  
Energetic Electrons ◽  
Turbulent Spectra ◽  
Kinetic Alfvén Waves

AbstractSome recent observations of solar corona suggest that the kinetic Alfvén waves (KAWs) turbulence may be responsible for electron acceleration in solar corona and coronal heating. In the present research, we investigate the turbulent spectra of KAW due to filamentation process in the presence of Landau damping and particle energization. We present here the numerical simulation of model equation governing the nonlinear dynamics of the KAW in the presence of Landau damping. When the ponderomotive and Joule heating nonlinearities are incorporated in the KAW dynamics, the power spectra of the turbulent field is evaluated and used for particle heating. Our results reveal the formation of damped coherent magnetic filamentary structures and the turbulent spectra. The effect of Landau damping is to make the turbulent spectra steeper. Two types of scalings k−3.6 and k−4 have been obtained. We have studied the turbulence with different initial conditions. Using the Fokker–Planck equation with the new velocity space diffusion coefficient, we find the distribution function of energetic electrons in these turbulent structures. Landau damped KAWs may be responsible for the acceleration of the energetic electrons in solar corona and coronal heating.

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