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Identification of the Coronal Sources of the Fast Solar Wind

S. Giordano·E. Antonucci·G. Noci·M. Romoli·J. L. Kohl
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Abstract

The present spectroscopic study of the ultraviolet coronal emission in a polar hole, detected on April 6-9, 1996 with the Ultraviolet Coronagraph Spectrometer aboard the SOHO spacecraft, identifies the inter-plume lanes and background coronal hole regions as the channels where the fast solar wind is preferentially accelerated. In inter-plume lanes, at heliocentric distance 1.7 \rsun, the corona expands at a rate between 105 km/s and 150 km/s, that is, much faster than in plumes where the outflow velocity is between 0 km/s and 65 km/s. The wind velocity is inferred from the Doppler dimming of the O VI $λλ$ 1032, 1037 Ålines, within a range of values, whose lower and upper limit corresponds to anisotropic and isotropic velocity distribution of the oxygen coronal ions, respectively.

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S. Giordano, E. Antonucci, G. Noci, M. Romoli, J. L. Kohl. 2000-01-14. Identification of the Coronal Sources of the Fast Solar Wind. https://doi.org/10.1086/312525

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