CGS: Collisionless Galactic Simulator
Abstract
CGS (Collisionless Galactic Simulator) uses Fourier techniques to solve the Possion equation 𕑈Φ = 4πGρ, relating the mean potential Φ of a system to the mass density ρ. The angular dependence of the force is treated exactly in terms of the singleparticle Legendre polynomials, which preserves accuracy and avoids systematic errors. The density is assigned to a radial grid by means of a cloudincell scheme with a linear kernel, i.e., a particle contributes to the density of the two closest cells with a weight depending linearly on the distance from the center of the cell considered. The same kernel is then used to assign the force from the grid to the particle. The time step is chosen adaptively in such a way that particles are not allowed to cross more than one radial cell during one step. CGS is based on van Albada's code (1982) and is distributed in the NEMO (ascl:1010.051) Stellar Dynamics Toolbox.
 Publication:

Astrophysics Source Code Library
 Pub Date:
 April 2019
 Bibcode:
 2019ascl.soft04003T
 Keywords:

 Software