The Palomar High-precision Astrometric Search for Exoplanet Systems (PHASES) has monitored 37 sub-arcsecond binary systems to determine whether their Keplerian orbits are perturbed by faint astrometric companions to either star. Software has been developed to evaluate the regions in a companion mass-period phase space in which the PHASES observations can exclude the possibility of face-on orbit perturbations. We present results for 8 systems for which astrometric companions with masses as small as those of giant planets can be excluded.
@article{arxiv.astro-ph/0608640,
title = {Limits to Tertiary Astrometric Companions in Binary Systems},
author = {Matthew W. Muterspaugh and Benjamin F. Lane and S. R. Kulkarni and B. F. Burke and M. M. Colavita and M. Shao},
journal= {arXiv preprint arXiv:astro-ph/0608640},
year = {2008}
}