The outer limit of the life supporting zone of exoplanets having CO2-rich atmospheres: Virtual exoplanets and Kepler planetary candidates

CO₂ rich atmospheres have been considered for the outer limit of the classic water habitable zone. Here we provide a database for the outer limit of the life supporting zone consisting of a sulfuric acid, a water and a water/ammonia mixture (15 wt% ammonia) habitable zone for virtual exoplanets having CO₂-rich atmospheres and orbiting G-, K-, or M-dwarf stars. We used recent CO₂ line and continuum absorption data for CO₂ pressures up to 100 bar for our simulations. Scenarios for different stellar spectra, stellar fluxes, planetary surface albedos, atmospheric pressures and planetary masses are explored. One notable result is that the surface temperature does not strongly increase if CO₂ pressure is larger than approximately 25 bar, due to increased Rayleigh scattering or CO₂ condensation at the surface and a thereby reduced greenhouse effect in these cases. The database is created for virtual exoplanets and applied to Kepler planetary candidates. All of the considered planetary candidates likely lie within the outer limit of the life supporting zone.