The interaction of dark matter cusp with the baryon component in disk galaxies

TL;DR

This study uses high-resolution simulations to explore how the formation and evolution of disk galaxies influence dark matter distribution, highlighting the roles of star formation, feedback, and disk structures.

Contribution

It demonstrates that star formation and supernova feedback resolve the dark matter cusp problem and shows how baryonic structures affect dark halo shape.

Findings

Star formation and feedback resolve the dark matter cusp issue.

Dark matter distribution becomes more symmetric with baryonic interactions.

Galactic disk structures influence the shape of the dark halo.

Abstract

In this paper we examine the effect of the formation and evolution of the disk galaxy on the distribution of dark halo matter. We have made simulations of isolated dark matter (DM) halo and two component (DM + baryons). N-body technique was used for stellar and DM particles and TVD MUSCL scheme for gas-dynamic simulations. The simulations include the processes of star formation, stellar feedback, heating and cooling of the interstellar medium. The results of numerical experiments with high spatial resolution let us to conclude in two main findings. First, accounting of star formation and supernova feedback resolves the so-called problem of cusp in distribution of dark matter predicted by cosmological simulations. Second, the interaction of dark matter with dynamic substructures of stellar and gaseous galactic disk (e.g., spiral waves, bar) has an impact on the shape of the dark halo. In particular, the in-plane distribution of dark matter is more symmetric in runs, where the baryonic component was taken into account.