Terrestrial planet formation around a Centauri B

The late stages of terrestrial planet formation around each star in the alpha Centauri AB binary system are modeled using a recently developed symplectic algorithm designed to follow N-body systems with two dominant masses. Each integration begins with a circumstellar disk consisting of fourteen large embryos embedded in a disk of smaller planetesimals orbiting one star, and we follow the evolution of the accreting bodies for 200 Myr - 1 Gyr. This paper describes simulations in which the circumstellar disk lies in the binary orbital plane and is centered around alpha Centauri B, and they are compared with recent simulations of terrestrial planet formation in the solar system. Simulations of terrestrial planet growth around a Cen A are discussed elsewhere (Quintana et al. 2002). In both cases, the binary companion has a similar effect on terrestrial planet formation around the central star as Jupiter and Saturn have around the sun; i.e., the companion determines an outer boundary for the terrestrial region but doesn't prevent the formation of terrestrial planets.