Planet Formation in Binaries - Planetary Exploration and Science: Recent Results and Advances - page 315

Fig. 13.8 Temporal evolution of the terrestrial planet growth in a binary system with a mass ratio
of 0.5 and for different values of the eccentricity .e b / and semimajor axis .a b / of the binary (Taken
from Haghighipour and Raymond 2007 , courtesy of the Astrophysical Journal)
the snapshots of one of such simulations. During the course of the integration, the
embryos in part of the disc close to the giant planet are dynamically excited. As a
result of the interaction of embryos with one another, the orbital excitation of these
objects is transmitted to other bodies in closer orbits causing many of them to be
scattered out of the system or undergo radial mixing. In the simulation of Fig. 13.8 ,
this process results in formation of a planet slightly larger than Earth and with a
large reservoir of water.
An interesting result of the Haghighipour and Raymond ( 2007 ) numerical
exploration is that assuming the first stages of planet formation were successful ,
binaries with moderate to large perihelia and with giant planets on low-eccentricity
orbits are most favourable for Earth-like planet formation. Similar to the formation
of terrestrial planets around single stars, where giant planets, in general, play
destructive roles, a strong interaction between the secondary star and the giant planet
in a binary planetary system (i.e. a small binary perihelion) increases the orbital
eccentricity of this object and results in the removal of the terrestrial planet-forming
materials from the system.