Models of giant planet formation with migration and disc evolution

¹ Physikalisches Institut, University of Bern, Sidlerstrasse 5, 3012 Bern, Switzerland e-mail: yann.alibert@phim.unibe.ch
² Theoretical Astrophysics Group, University of Leicester, Leicester LE1 7RH, UK

Received: 20 September 2004
Accepted: 13 December 2004

Abstract

We present a new model of giant planet formation that extends the core-accretion model of Pollack et al. (1996, Icarus, 124, 62) to include migration, disc evolution and gap formation. We show that taking these effects into account can lead to much more rapid formation of giant planets, making it compatible with the typical disc lifetimes inferred from observations of young circumstellar discs. This speed up is due to the fact that migration prevents the severe depletion of the feeding zone as observed in in situ calculations. Hence, the growing planet is never isolated and it can reach cross-over mass on a much shorter timescale. To illustrate the range of planets that can form in our model, we describe a set of simulations in which we have varied some of the initial parameters and compare the final masses and semi-major axes with those inferred from observed extra-solar planets.