Reproduction of NGC1052-DF4 by self-interacting dark matter: dark matter deficiency and tidal features

TL;DR

This paper demonstrates through simulations that self-interacting dark matter can explain the observed dark matter deficiency and tidal features of the ultra-diffuse galaxy NGC1052-DF4, supporting its tidal formation scenario.

Contribution

The study introduces N-body simulations with SIDM to reproduce the dark matter deficiency and tidal features of DF4, aligning with deep observational data.

Findings

SIDM significantly reduces the DM-to-star mass ratio in the galaxy's center.

Simulations accurately reproduce the tidal tails observed in DF4.

Self-interacting dark matter influences galaxy evolution and tidal feature formation.

Abstract

Observations of the velocity dispersion indicate a severe dark matter (DM) deficit in the ultra-diffuse galaxy, NGC1052-DF4 (DF4). The ultra-deep images obtained with the Gemini telescope, which has the deepest imaging data till now, confirm the presence of tidal tails in DF4, suggesting its tidal formation. To enhance tidal effects, we consider the self-interaction among DM particles. Using an N-body simulation in the scenario of self-interacting dark matter (SIDM), we reproduce a DM-deficient galaxy that is consistent with all observational data of DF4. Specifically, our simulation result yields an extremely low DM-to-star mass ratio and a radial surface brightness profile very similar to that from deep images, showing accurate tidal features. By performing simulations with similar tidal effects and various cross-sections of SIDM, we show a significant impact of SIDM on the DM-to-star mass ratio in the central region of the galaxy. Our work confirms the tidal formation of DF4 in theory.