摘要：We present exoplanet occurrence rates estimated with approximate Bayesian computation for planets with radii between 0.5 and 16 R⊕ and orbital periods between 0.78 and 400 days orbiting FGK dwarf stars.We base our results on an independent planet catalog compiled from our search of all ~200,000 stars observed over the Kepler mission, with precise planetary radii supplemented by Gaia DR2-incorporated stellar radii.We take into account detection and vetting efficiency, planet radius uncertainty, and reliability against transit-like noise signals in the data.By analyzing our FGK occurrence rates as well as those computed after separating F-, G-, and K-type stars, we explore dependencies on stellar effective temperature, planet radius, and orbital period.We reveal new characteristics of the photoevaporation-driven "radius gap" between ~1.5 and 2 R⊕, indicating that the bimodal distribution previously revealed for P < 100 days exists only over a much narrower range of orbital periods, above which sub-Neptunes dominate and below which super-Earths dominate.Finally, we provide several estimates of the "eta-Earth" value—the frequency of potentially habitable, rocky planets orbiting Sun-like stars.For planets with sizes 0.75–1.5 R⊕ orbiting in a conservatively defined habitable zone (0.99–1.70 au) around G-type stars, we place an upper limit (84.1th percentile) of <0.18 planets per star.
