CONICET | Buscador de Institutos y Recursos Humanos

To study the terrestrial-type planet formation during the post oligarchicgrowth, the initial distributions of planetary embryos and planetesimals usedin N-body simulations play an important role. Most of these studies typicallyuse ad hoc initial distributions based on theoretical and numerical studies. Weanalyze the formation of planetary systems without gas giants around solar-typestars focusing on the sensitivity of the results to the particular initialdistributions of planetesimals and embryos. The formation of terrestrialplanets in the habitable zone (HZ) and their final water contents are topics ofinterest. We developed two different sets of N-body simulations from the sameprotoplanetary disk. The first set assumes ad hoc initial distributions forembryos and planetesimals and the second set obtains these distributions fromthe results of a semi-analytical model which simulates the evolution of thegaseous phase of the disk. Both sets form planets in the HZ. Ad hoc initialconditions form planets in the HZ with masses from 0.66M⊕ to2.27M⊕. More realistic initial conditions obtained from asemi-analytical model, form planets with masses between 1.18M⊕ and2.21M⊕. Both sets form planets in the HZ with water contents between4.5% and 39.48% by mass. Those planets with the highest water contents respectto those with the lowest, present differences regarding the sources of watersupply. We suggest that the number of planets in the HZ is not sensitive to theparticular initial distribution of embryos and planetesimals and thus, theresults are globally similar between both sets. However, the main differencesare associated to the accretion history of the planets in the HZ. Thesediscrepancies have a direct impact in the accretion of water-rich material andin the physical characteristics of the resulting planets.