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arXiv · 0904.3733

The Evolutionary State of the Massive Interacting Binary BD+36 4063

S. J. Williams·D. R. Gies·R. A. Matson·W. Huang
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Abstract

We present a spectroscopic and photometric analysis of the remarkable massive binary system, BD +36 4063. We argue that the visible ON star is undergoing a rapid mass transfer episode that results in a thick and opaque disk that surrounds and renders invisible its massive companion. A comparison of the projected rotational velocity and the orbital semiamplitude of the visible star indicates a mass ratio near unity. Models for conservative mass transfer show that the equal mass state occurs at the point of minimum separation, and we argue that BD +36 4063 may represent the first system identified at this rapid and rare stage of massive binary evolution.

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S. J. Williams, D. R. Gies, R. A. Matson, W. Huang. 2009-04-23. The Evolutionary State of the Massive Interacting Binary BD+36 4063. https://doi.org/10.1088/0004-637x%2F696%2F2%2Fl137

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