# Stellar content, planetary nebulae, and globular clusters of [KKS2000]04 (NGC1052-DF2)

## TL;DR

This study analyzes the stellar, globular cluster, and planetary nebulae systems of galaxy [KKS2000]04 using spectroscopic data, revealing its old, metal-poor stellar population and confirming some globular clusters, while arguing against it being a dark matter-free tidal dwarf galaxy.

## Contribution

It provides new spectroscopic evidence for the stellar population and globular clusters of [KKS2000]04, and evaluates its nature and formation history in detail.

## Key findings

- Detected two new planetary nebulae.
- Confirmed membership of 5 globular clusters.
- Stars are predominantly old and metal-poor.

## Abstract

[KKS2000]04 (NGC1052-DF2) has become a controversial and well-studied galaxy after the claims suggesting a lack of dark matter and the presence of an anomalously bright globular cluster (GC) system around it. A precise determination of its overall star formation history (SFH) as well as a better characterisation of its GC or planetary nebulae (PN) systems are crucial aspects to: i) understand its real nature, in particular placing it within the family of ultra diffuse galaxies; ii) shed light on its possible formation, evolution, and survival in the absence of dark matter. With this purpose we expand on the knowledge of [KKS2000]04 from the analysis of OSIRIS@GTC spectroscopic data. On the one hand, we claim the possible detection of two new PNe and confirm membership of 5 GCs. On the other hand, we find that the stars shaping [KKS2000]04 are intermediate-age to old (90\% of its stellar mass older than 5 Gyr, average age of 8.7 $\pm$ 0.7 Gyr) and metal-poor ([M/H] $\sim$ -1.18 $\pm$ 0.05), in general agreement with previous results. We do not find any clear hints of significant changes in its stellar content with radius. In addition, the possibility of [KKS2000]04 being a tidal dwarf galaxy with no dark matter is highly disfavoured.