A recent study by Bancelin et al. (AJ,2017) showed the strong influence of fragmentation and water-loss from small bodies on the final outcome of impacts in binary star systems. To improve the so-called perfect merging (also known as hit-and-stick) mechanism of two colliding bodies, Smooth-Particle-Hydrodynamic (SPH) simulations have been carried out to provide a deeper insight into the collision scenario and show volatile and material loss during impact. Therefore, we present a detailed investigation of the collision parameters, namely the encounter velocity and the collision angle for various binary star configurations (with stellar distances from 50 to 100 au). In addition to a circum-stellar disk of about 1500 gravitational interacting bodies of either Ceres-, Moon- or Mars-size which surrounds the primary star, a Jupiter-mass planet also orbits this star at a larger distance than the disk. For the computations of the N-body interaction we used our recently developed GPU N-body integrator. The evolution of the embryo or planetesimal disk has been calculated for some million. years. In this study, the resulting collision parameters show clearly differences for embryos and planetesimals. While most of the embryo collisions indicate low impact velocities we have found significantly higher encounter velocities which indicates more destructive events in a planetesimal disk.
[Poster PDF File]