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E. W. Thommes (Astronomy Dept, UC Berkeley, Berkeley, CA), M. J. Duncan (Astronomy Dept, Queen's University, Kingston, Ontario), H. F. Levison (Southwest Research Institute, Boulder, CO)
Runaway growth ends when the largest protoplanets dominate the dynamics of the planetesimal disk; the subsequent self-limiting accretion mode is referred to as ``oligarchic growth''. We use the oligarchic growth model to obtain global estimates of the planet formation rate throughout the protoplanetary disk. Comparison is made to numerical simulations; these suggest that planetesimal accretion stagnates well before protoplanets reach their idealized isolation mass. A further complication comes in the form of gas disk tidal torques, which should cause rapid orbital decay of bodies with masses in the range 10-1 - 102 Earth masses. We investigate the effect of this mechanism on protoplanet growth in the region of the giant planets.