Arxiv:Astro-Ph/9704191V1 18 Apr 1997 H Uoensuhr Observatory
Doppler Imagery of the Spotted RS CVn Star HR 1099 (= V711 Tau) from 1981 - 19921 Steven S. Vogt, Artie P. Hatzes2, Anthony A. Misch UCO/Lick Observatory, Board of Studies in Astronomy and Astrophysics University of California, Santa Cruz, CA 95064 and M. K¨urster Institut f¨ur Astronomie, Universit¨at Wien, T¨urkenschanzstr. 17, A-1180 Wien, Austria Received 16 April 1997; accepted Submitted to: Astrophysical Journal Supplement arXiv:astro-ph/9704191v1 18 Apr 1997 1Based on observations collected at UCO/Lick Observatory, McDonald Observatory, and the European Southern Observatory. 2now at McDonald Observatory, The University of Texas at Austin, Austin, TX 78712 –2– ABSTRACT Author One, Author Two, Authors ad infinitum (affiliations if desired belong in parentheses, but don’t include full snail mail addresses) We present a set of 23 Doppler images of the spotted RS CVn star HR 1099 ( = V711 Tau = HD 22468) obtained from 1981 to 1992. HR 1099 shows a large cool polar spot which has persisted for the 11 years of this study and other low-latitude spots which come and go on relatively short (less than 1-year) timescales, and which can emerge anywhere on the star. The polar spot has variable protuberances which look very similar to the time-variable vertical extensions of the Sun’s polar coronal hole. The area of the polar spot and its extensions shows marginal evidence of being periodically variable in time with a period of about 3 yrs. and an amplitude of about 1%, perhaps indicative of a weak cycle, but not yet conclusive. Comparison of our Doppler images with previously published ‘few-spot’- model fits to the light curves shows that such simple spot model solutions are often misleading and nonunique, particularly when the light curve amplitude is small.
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