Institute of Astronomy

GENGA: a GPU code for planet formation and planetary system evolution

SpeakerTalk DateTalk Series
Simon Grimm28 July 2014Across HR 2014 Posters


We present GENGA, a GPU implementation of a hybrid symplectic N-body integrator, designed to integrate planet and planetesimal dynamics in the late stage of planet formation. It can also be used for high accuracy integration of the n-body problem, for example to study the long term stability of planetary systems. GENGA can be used with three simulation modes: Integration of up to 2048 interacting massive bodies, integration with up to a million test particles, or simultaneous parallel integration of more than 100'000 individual planetary systems. I will also discuss the accuracy of the code and show its limitations. Especially the complex treatment and outcomes of close encounters between planets or planetesimals. We present two applications of GENGA: Firstly, the dynamics of planetesimals and the late stage of rocky planet formation due to planetesimal collisions. And secondly, a dynamical stability analysis of an exoplanetary system with an additional hypothetical super earth, which shows that in some multiple planetary systems, additional super earths could exist without perturbing the dynamical stability of the other planets (Elser et al. 2013).