CS11 Abstract

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Latest Doppler images of the RS CVn binary EI Eridani

A. Washuettl(1,2), K. G. Strassmeier(1), A. Collier-Cameron(2)

(1) Institute for Astronomy, University of Vienna, Tuerkenschanzstr. 17, A-1180 Vienna, Austria
(2) School of Physics and Astronomy, St. Andrews University, North Haugh, St. Andrews, Fife KY16 9SS, Scotland

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EI Eridani ( = HD 26337) is a rapidly rotating active binary star. 
Previous investigations indicated a permanent or at least long-lived large
polar feature which changes its shape on comparatively short timescales
(of the order of one month). Occasionally, small spots at low latitudes
appear as well. We present new Doppler images from different epochs
confirming the stability of the polar spot. For one specific data set we
applied two different Doppler-imaging codes and carried out a thorough
comparison of both techniques. Both reproduce reasonably similar images. 
Additionally, we present new photometric observations which do not confirm
the anticipated 11 years magnetic cycle. 
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