Tidal Formation of Dark Matter Deficit Diffuse Galaxy NGC 1052-DF2 by SIDM

Abstract

Observations have revealed a significant dark matter deficit in the ultradiffuse galaxy NGC 1052-DF2 (DF2). It is widely accepted that the formation of this unique galaxy can be attributed to the tidal stripping of its host galaxy, NGC 1052. In this study, we simulate the evolution of a satellite system containing globular clusters (GCs) within an accreting host halo in the framework of self-interacting dark matter (SIDM). Our simulation results suggest that the heightened tidal stripping resulting from dark matter (DM) self-interactions can give rise to the transformation of a conventional dwarf galaxy into a dark matter deficit galaxy resembling DF2. Furthermore, we demonstrate that a DF2 analog can also be produced on an orbit with a greater pericenter distance by increasing the strength of DM self-interactions. This suggests that the issue of extreme orbital parameters can be mitigated by implementing the SIDM model. The distributions of the GC population derived in our SIDM simulation are consistent with the observed characteristics of DF2. The potential for reproducing DF2 and its GC population in the cold dark matter scenario is also discussed.

Keywords

• Dark matter