Numerical evolution of self-gravitating halos of self-interacting dark matter

TL;DR

This paper presents an efficient numerical scheme for simulating self-gravitating systems with self-interacting dark matter, capturing core formation and collapse phenomena with less computational cost than traditional methods.

Contribution

It introduces a modified numerical approach that efficiently models self-interacting dark matter effects in spherical systems, adaptable to various cross sections and applicable to globular clusters.

Findings

Simulation shows initial flattening of NFW halo core

Demonstrates gravothermal collapse leading to dense core

Method is computationally efficient and versatile

Abstract

We discuss a modification of a recently developed numerical scheme for evolving spherically symmetric self-gravitating systems to include the effects of self-interacting dark matter. The approach is far more efficient than traditional N-body simulations and cross sections with different dependencies on velocity and scattering-angle are easily accommodated. To demonstrate, we provide results of a simulation, which runs quickly on a personal computer, that shows the expected initial flattening of the inner region of an NFW halo as well as the later gravothermal collapse instability that leads to a dense core at the galactic center. We note that this approach can also be used, with some augmentation, to simulate the dynamics in globular clusters by modeling gravitational hard scattering as a self-interaction.