Dark matter substructure in numerical simulations: a tale of discreteness noise, runaway instabilities, and artificial disruption

• DOI: 10.1093/mnras/sty084
• Publication Date: 2018-01-09T16:25:46Z
• Authors: Frank C van den B...; Go Ogiya
• Keywords: Substructure

To gain understanding of the complicated, non-linear, and numerical processes associated with tidal evolution dark matter subhaloes in simulation, we perform a large suite idealized simulations that follow individual N-body fixed, analytical host halo potential. By varying both physical parameters, investigate under what conditions undergo disruption. We confirm conclusions from our more assessment van den Bosch et al. most disruption is origin; as long subhalo resolved sufficient mass force resolution, bound remnant survives. This implies state-of-the-art cosmological still suffer significant overmerging. demonstrate this mainly due to inadequate softening, which causes excessive loss artificial In addition, show are susceptible runaway instability triggered by amplification discreteness noise presence field. These two conspire put serious limitations on reliability substructure simulations. present criteria can be used assess whether reliable or not, advocate satisfy either these discarded further analysis. discuss potential implications work for several areas astrophysics.