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The Masses Of The B-Stars In The High Galactic Latitude Eclipsing Binary IT Lib

John C. Martin
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Abstract

A number of blue stars which appear to be similar to Population I B-stars in the star forming regions of the galactic disk are found more than 1 kpc from the galactic plane. Uncertainties about the true distances and masses of these high latitude B-stars has fueled a debate as to their origin and evolutionary status. The eclipsing binary IT Lib is composed of two B-stars, is approximately one kiloparsec above the galactic plane, and is moving back toward the plane. Observations of the light and velocity curves presented here lead to the conclusion that the B-stars in this system are massive young main-sequence stars. While there are several possible explanations, it appears most plausible that the IT Lib system formed in the disk about 30 million years ago and was ejected on a trajectory taking it to its present position.

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John C. Martin. 2002-10-28. The Masses Of The B-Stars In The High Galactic Latitude Eclipsing Binary IT Lib. https://doi.org/10.1086/345433

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