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Chromospheric variation in cool supergiant stars

Published online by Cambridge University Press:  25 May 2016

J. A. Eaton  and
G. W. Henry
J. A. Eaton
Affiliation:
Tennessee State University Nashville, TN, USA
G. W. Henry
Affiliation:
Tennessee State University Nashville, TN, USA

Abstract

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Stars close to the main sequence, if they rotate rapidly enough, show magnetic activity in the form of spots, active regions, and strong chromospheres. With the exception of the hybrid stars, stars cooler and more luminous than the so-called Linsky-Haisch dividing line, in contrast, are not known to have any of these phenomena. In fact, it is not clear such stars, even though rotating and convective, show any magnetic phenomena at all. We discuss (1) photometry used to search for spots in the hybrid stars, which we have not found, and (2) evidence for chromospheric variation in K supergiants that takes the form of enhanced winds, but which may be analogous to the activity of stars closer to the main sequence.

Type
Session IV: “Outer Atmospheric Structure”
Information
Symposium - International Astronomical Union , Volume 176: Stellar Surface Structure , 1996 , pp. 415 - 422
Copyright
Copyright © Kluwer 1996 

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