The solar wind is the continuous outflow of ionized gas from the solar corona. It is pervaded with fluctuations of very
wide range of scales. At large scales these fluctuations are mainly Alfven waves and their spectrum follows power law
with spectral index -5/3 thus following Kolmogorov’s spectrum of the fluid turbulence. At smaller scales, when
wavelength becomes comparable to ion giro-radius Alfven waves become dispersive (kinetic Alfven waves) and kinetic
dissipation of the waves (e.g., by Landau damping) also becomes possible. The spectrum of the solar wind turbulence at
these scales becomes steeper. There is no current consensus what is the dominant physical mechanism operating at these
scales. Observed steeper spectra are explained as a result of kinetic dissipation of turbulent fluctuations or caused by
dispersive properties of kinetic Alfven waves. The study of the small scale turbulence in the solar wind is important not
only in the context of understanding solar wind dynamics, such as understanding exact mechanisms of energy cascade,
dissipation of turbulence, plasma heating and particle acceleration, but also for understanding the dissipation of
electromagnetic turbulence in collisionless plasmas in general. Obtaining reliable high frequency spectra of the solar
wind parameters is very challenging task. At high frequencies the spectra of both magnetic field and plasma parameters
are significantly affected by measurement uncertainties. Presented project implies study of small scale turbulence in the
solar wind by means of theoretical research of kinetic Alfven wave turbulence and solar wind data analysis. In particular,
for explanation of the high frequency solar wind observations we intend to develop a model of kinetic Alfven wave
turbulence which will include active turbulent cascade and kinetic dissipation at the same time. We will also study
influence of imbalance between kinetic Alfven waves propagating along and backward with respect to the background
magnetic field on energy cascade features of the turbulence. We plan to test various theoretical predictions (both obtained
in the framework of this project and belonging to alternative models) analyzing high frequency spectra of the solar wind
magnetic field and plasma parameters.
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