Sensitivity of the Astrometric Technique in Detecting Outer Planets

摘要

With the advent of optical interferometers that will be coming online in thenext decade, radial velocity searches for extra-solar planets will becomplemented by high angular resolution astrometric measurements. In thispaper, we explore the sensitivity of the astrometric technique, and develop ananalytical understanding of the sensitivity in the regime where the orbitalperiod is longer than the time-baseline of the survey. As in an earlier paperthat dealt with the radial velocity technique, our analysis of the astrometrictechnique utilizes both the orbital amplitude and phase.