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arXiv · 1009.1171

Analysis of the MOST light curve of the heavily spotted K2IV component of the single-line spectroscopic binary II Pegasi

Michal Siwak·Slavek M. Rucinski·Jaymie M. Matthews·Rainer Kuschnig·David B. Guenther·Anthony F. J. Moffat·Dimitar Sasselov·Werner W. Weiss
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Abstract

Continuous photometric observations of the visible component of the single-line, K2IV spectroscopic binary II Peg carried out by the MOST satellite during 31 consecutive days in 2008 have been analyzed. On top of spot-induced brightness modulation, eleven flares were detected of three distinct types characterized by different values of rise, decay and duration times. The flares showed a preference for occurrence at rotation phases when the most spotted hemisphere is directed to the observer, confirming previous similar reports. An attempt to detect a grazing primary minimum caused by the secondary component transiting in front of the visible star gave a negative result. The brightness variability caused by spots has been interpreted within a cold spot model. An assumption of differential rotation of the primary component gave a better fit to the light curve than a solid-body rotation model.

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Michal Siwak, Slavek M. Rucinski, Jaymie M. Matthews, Rainer Kuschnig, David B. Guenther, Anthony F. J. Moffat, Dimitar Sasselov, Werner W. Weiss. 2010-09-06. Analysis of the MOST light curve of the heavily spotted K2IV component of the single-line spectroscopic binary II Pegasi. https://doi.org/10.1111/j.1365-2966.2010.17109.x

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