Nonlinear kinetic Alfven waves associated with saturating nonlinearity: applications to solar wind and coronal heating

2002 ◽  
Vol 64 (5-6) ◽  
pp. 661-668 ◽  
Author(s):  
Anita Shukla ◽  
R.P. Sharma
Keyword(s):  
Solar Wind ◽  
Alfven Waves ◽  
Coronal Heating ◽  
Alfvén Waves ◽  
Nonlinear Kinetic ◽  
Kinetic Alfvén Waves

scholarly journals Coronal heating and wind acceleration by nonlinear Alfvén waves – global simulations with gravity, radiation, and conduction

2008 ◽  
Vol 15 (2) ◽  
pp. 295-304 ◽  
Author(s):  
T. K. Suzuki
Keyword(s):  
Solar Wind ◽  
Alfven Waves ◽  
Coronal Heating ◽  
Alfvén Waves ◽  
Flux Tubes ◽  
Giant Stars ◽  
Solar Winds ◽  
Dynamical Simulations ◽  
Consistent Manner ◽  
Red Giant

Abstract. We review our recent results of global one-dimensional (1-D) MHD simulations for the acceleration of solar and stellar winds. We impose transverse photospheric motions corresponding to the granulations, which generate outgoing Alfvén waves. We treat the propagation and dissipation of the Alfvén waves and consequent heating from the photosphere by dynamical simulations in a self-consistent manner. Nonlinear dissipation of Alfven waves becomes quite effective owing to the stratification of the atmosphere (the outward decrease of the density). We show that the coronal heating and the solar wind acceleration in the open magnetic field regions are natural consequence of the footpoint fluctuations of the magnetic fields at the surface (photosphere). We find that the properties of the solar wind sensitively depend on the fluctuation amplitudes at the solar surface because of the nonlinearity of the Alfvén waves, and that the wind speed at 1 AU is mainly controlled by the field strength and geometry of flux tubes. Based on these results, we point out that both fast and slow solar winds can be explained by the dissipation of nonlinear Alfvén waves in a unified manner. We also discuss winds from red giant stars driven by Alfvén waves, focusing on different aspects from the solar wind.

Potential role of kinetic Alfvén waves and whistler waves in solar wind plasmas

2016 ◽  
Vol 361 (7) ◽  
Author(s):  
P. Nandal ◽  
N. Yadav ◽  
R. P. Sharma ◽  
M. L. Goldstein
Keyword(s):  
Solar Wind ◽  
Potential Role ◽  
Alfven Waves ◽  
Alfvén Waves ◽  
Whistler Waves ◽  
Kinetic Alfvén 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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