Orchestra: NBody
Calculate orbits of ensemble of planets orbiting a star
- Yields accurate gravity field
- Includes mergers and fragmentation of large planets
Advantages
- Essential for ensembles of massive planets
- Treats gas accretion and migration
- Infers final planet masses and orbits
Disdvantages
- Fails for planetesimals
- No interaction with leftover planetesimals or dust grains
- Cannot model formation of gas giant planets
Approach:
- Friends-of-friends for nearest neighbors
- Hierarchical treatment of timesteps
- Force-evaluations calculated directly
- Treecode backup for large numbers of particles
- Input drag from interactions with gas & small bodies
- Input accretion from planetesimal swarm
- Accuracy is machine precision for orbits
- O(N2) for force-solver
Code is extensively tested