Symplectically Integrating Close Encounters with the Sun

We present a new symplectic algorithm that has the desirable property of being able to integrate close perihelion passages with the Sun. We have combined this algorithm with our fast and efficient algorithm for studying planetesimal dynamics and planet formation, known as SyMBA. The resulting code can symplectically integrate close encounters between all objects during a simulation, thus removing the main limitation of SyMBA (and related schemes). We believe that this algorithm will be a valuable tool for the study of the violent stages of planet formation.