The coronal structure of Speedy Mic - I. A densely packed prominence system beyond corotation

  title={The coronal structure of Speedy Mic - I. A densely packed prominence system beyond corotation},
  author={Nick J. Dunstone and John R. Barnes and Andrew Collier Cameron and Moira M. Jardine},
  journal={Monthly Notices of the Royal Astronomical Society},
We present new observations of the prominence system on the K3 dwarf Speedy Mic (BO Mic, HD 197890). Using an improved technique to track the absorption features in Hα we find a very active prominence system with approximately 10 prominences on the observable hemisphere per rotation. From a total of 25 prominences, we find an average axial distance of (2.85 ± 0.54) R ∗ which is twice the corotation radius above the stellar surface. We discuss the consequences of these observations on the nature… 

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