A particle-based hybrid code for planet formation

TL;DR

This paper presents a new hybrid particle-based code for planet formation that combines N-body simulations with statistical methods to efficiently model planetary accretion involving numerous planetesimals.

Contribution

The paper introduces a novel hybrid simulation code that integrates N-body and statistical routines for more efficient and accurate modeling of planetary accretion processes.

Findings

Hybrid code shows good agreement with analytic and pure N-body results.

Computational load is comparable or less than traditional N-body simulations.

Code includes hit-and-run bouncing but not fragmentation.

Abstract

We introduce a new particle-based hybrid code for planetary accretion. The code uses an $N$-body routine for interactions with planetary embryos while it can handle a large number of planetesimals using a super-particle approximation, in which a large number of small planetesimals are represented by a small number of tracers. Tracer-tracer interactions are handled by a statistical routine which uses the phase-averaged stirring and collision rates. We compare hybrid simulations with analytic predictions and pure $N$-body simulations for various problems in detail and find good agreements for all cases. The computational load on the portion of the statistical routine is comparable to or less than that for the $N$-body routine. The present code includes an option of hit-and-run bouncing but not fragmentation, which remains for future work.