Convergence tests of SIDM N-body simulations

Self-interacting dark matter (SIDM) theory predicts that dark matter halos experience core collapse, a process where the halo's inner region rapidly increases in density and decreases in size. The N-body simulations used to study this process can suffer from numerical errors when simulation parameters are selected incorrectly. Optimal choices for simulation parameters are well-studied for cold dark matter (CDM) but are not deeply understood when self-interactions are included. In order to perform reliable N-body simulations and model core-collapse accurately we must understand the potential numerical errors, how to diagnose them, and what parameter selections must be made to reduce them. We use the Arepo N-body code to perform convergence tests of core-collapsing SIDM halos across a range of halo concentrations and SIDM cross-sections and quantify potential numerical issues related to mass resolution, timestep size, and gravitational softening length. Our tests discover that halos with ..., This dataset contains snapshots of simulations run in the N-body code Arepo, with the addition of a scattering interaction between dark matter particles. The snapshots are organized by simulation run and are saved as hdf5 files output by Arepo. The snapshots have not been processed, aside from the removal of some data (such as local particle density) to save space. The results of our publication can be replicated using the remaining particle data: mass, positions, velocities, potentials, number of scattering events, and ID numbers.
In addition to the N-body output, we also share reduced data files. These files contain halo central densities versus time and were computed from the N-body data using the method described in section II.D of our publication., , # Convergence tests of SIDM N-body simulations

The data here are the product of N-body simulations of self-interacting dark matter (SIDM). The simulations were run with the N-body code Arepo ([https://doi.org/10.1111/j.1365-2966.2009.15715.x)](https://doi.org/10.1111/j.1365-2966.2009.15715.x), including SIDM modifications ([https://doi.org/10.1111/j.1365-2966.2012.21182.x](https://doi.org/10.1111/j.1365-2966.2012.21182.x)).

Each compressed folder in this dataset corresponds to a set of convergence test simulations for a particular dark matter halo and SIDM cross-section. The folder names follow the same convention shown in Table 1 of our publication - where the number following C refers to the initial halo concentration, and the number following T refers to the estimated collapse time in Gyr. For example, C10T225 refers to the simulation set with a concentration of 10 and an approximate collapse time of 225 Gyr. A folder name that is followed by LOWRES contains data for the low-resolu...