[Previous] | [Session 93] | [Next]
J. P. Lloyd, M. C. Liu, J. R. Graham, D. Fischer, G. W. Marcy (University of California, Berkeley)
Precision radial velocity searches have produced a wealth of dynamical information on nearby stars, including the discovery of over 50 extrasolar planetary system candidates. The radial velocity information also probes stellar and sub-stellar companions in orbits of longer period than the limited baseline of precision radial velocity measurements.
We have undertaken a survey of the host stars of planetary systems, and long period radial velocity companions with the Lick Adaptive Optics system on the Shane 3-m telescope at Lick Observatory. With 0.15 arcsec (FWHM at K band), high contrast images we achieve with adaptive optics, we are sensitive to low mass companions at separations from 0.3 arcsec to our 10 arcsec (radius) field of view. Depending on the luminosity of the primary and observing conditions, we are sensitive to companions less luminous than the bottom of the main sequence at separations greater than a few arcsec. We report on several low mass proper motion companions to planet bearing stars. In cases where we do not detect a companion, we are able to place upper limits on possible masses and inclinations when coupled with the radial velocitity data.
This work is supported by the Center for Adaptive Optics under the STC Program of the National Science Foundation, Agreement No. AST-9876783