2013ApJ...767L..38L

Six P-type planets have been found thus far around five binary systems, i.e., Kepler-16b, 34b, 35b, 38b, and 47b and c, which are all Neptune- or Jupiter-like planets. The stability of planets and the habitable zones are influenced by the gravitational and radiative perturbations of binary companions. In this Letter, we check the stability of an additional habitable Earth-mass planet in each system. Based on our simulations in 10 Myr, a habitable "Earth" is hardly stable in Kepler-16, while a stable "Earth" in Kepler-47 close to the boundaries of the habitable zone is possible. In contrast, Kepler-34, 35, and 38 seem to have high probabilities of being able to tolerante a stable "Earth" in their habitable zones. The affects of transit time variations are quite small due to the small mass of an undetected "Earth," except that of Kepler-16b. With a time precision of 10^–3 day (∼88 s), an "Earth" in the corotational resonance with Kepler-16b can be detected in three years, while habitable "Earths" in the Kepler-34 and 38 systems can be detected in 10 yr. Habitable "Earths" in Kepler-35 and 47 are not likely to be detected in 10 yr under this precision.