The discovery efficiency of a direct imaging survey for exoplanets was not significant due to the low occurrence rate (<10%) of a planet that is detectable with the current instruments. However, the advent of the space telescope Gaia changed this situation. The high-precision Gaia proper motion (PM) measurements were compared with the Hipparcos ones to derive the accelerations of nearby stars. The gravitational interaction between a star and its co-moving companion generates the acceleration, which is therefore available as the sign of a companion even if its mass is comparable to that of Jupiter. This program observes 6 sun-like stars selected with the PM acceleration measurements using the high-contrast imager SCExAO/CHARIS. The targets have the youths confirmed by their rapid rotations (i.e., gyrochronology) or physical associations with the Hyades open cluster. Our observation plan was designed to detect a companion with a mass higher than ∼8 MJup for all the targets if the planet is located at >0.15′′; It can reach the detection of 2–4 MJup for three targets. For a discovered planet, we derive its dynamical mass and near-infrared spectrum to test evolutionary/atmospheric models for such cool objects.
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