Solar Wind Origin in Coronal Funnels

  title={Solar Wind Origin in Coronal Funnels},
  author={Chuanyi Tu and Cheng Zhou and Eckart Marsch and Lidong Xia and Liang Zhao and Jingxiu Wang and Klaus Wilhelm},
  pages={519 - 523}
The origin of the solar wind in solar coronal holes has long been unclear. We establish that the solar wind starts flowing out of the corona at heights above the photosphere between 5 megameters and 20 megameters in magnetic funnels. This result is obtained by a correlation of the Doppler-velocity and radiance maps of spectral lines emitted by various ions with the force-free magnetic field as extrapolated from photospheric magnetograms to different altitudes. Specifically, we find that Ne7… 

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