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arXiv · 0710.2127

The orbits of the quadruple star system 88 Tau A from PHASES differential astrometry and radial velocity

Benjamin F. Lane·Matthew W. Muterspaugh·Francis C. Fekel·Michael Williamson·Stanley Browne·Maciej Konacki·Bernard F. Burke·S. R. Kulkarni·M. M. Colavita·M. Shao
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Abstract

We have used high precision differential astrometry from the Palomar High-precision Astrometric Search for Exoplanet Systems (PHASES) project and radial velocity measurements covering a time-span of 20 years to determine the orbital parameters of the 88 Tau A system. 88 Tau is a complex hierarchical multiple system comprising a total of six stars; we have studied the brightest 4, consisting of two short-period pairs orbiting each other with an 18-year period. We present the first orbital solution for one of the short-period pairs, and determine the masses of the components and distance to the system to the level of a few percent. In addition, our astrometric measurements allow us to make the first determination of the mutual inclinations of the orbits. We find that the sub-systems are not coplanar.

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Benjamin F. Lane, Matthew W. Muterspaugh, Francis C. Fekel, Michael Williamson, Stanley Browne, Maciej Konacki, Bernard F. Burke, S. R. Kulkarni, M. M. Colavita, M. Shao. 2007-10-16. The orbits of the quadruple star system 88 Tau A from PHASES differential astrometry and radial velocity. https://doi.org/10.1086/520877

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