Kinetic Theory and Fast Wind Observations of the Electron Strahl

  title={Kinetic Theory and Fast Wind Observations of the Electron Strahl},
  author={Konstantinos Horaites and Stanislav Boldyrev and Lynn Bruce Wilson and Adolfo. F. Vi{\~n}as and Jan Merka},
  journal={Monthly Notices of the Royal Astronomical Society},
We develop a model for the strahl population in the solar wind -- a narrow, low-density and high-energy electron beam centered on the magnetic field direction. Our model is based on the solution of the electron drift-kinetic equation at heliospheric distances where the plasma density, temperature, and the magnetic field strength decline as power-laws of the distance along a magnetic flux tube. Our solution for the strahl depends on a number of parameters that, in the absence of the analytic… 

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