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arXiv · 1106.1694

A Multicolour Photometric Study of the neglected eclipsing binary FT Ursae Majoris

Jin-Zhao Yuan
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Abstract

The multicolour photometric observations of the neglected eclipsing binary FT Ursae Majoris (FT UMa) were obtained in 2010. The 2003 version of Wilson-Devinney code was used to analyze the light curves in $B$, $V$, and $R$ bands simultaneously. Based on the spectroscopic mass ratio $q=0.984$ published by Pribulla et al., it is found that FT UMa is an evolved contact binary with a contact degree of 15.3%. The low amplitude of light variations, $\sim 0.15$ mag, arises mainly from a moderately low inclination angle of $i=62.^{\circ}80$ and almost identical components in size rather than the light dilution of a third component, which contributes light of only $\sim 10%$

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Jin-Zhao Yuan. 2011-06-09. A Multicolour Photometric Study of the neglected eclipsing binary FT Ursae Majoris. https://doi.org/10.1088/1674-4527/11/10/004

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