Extending Ultra-Diffuse Galaxy abundances to Milky Way analogues

DOI: 
10.1093/mnras/stac3622
Publication date: 
15/02/2023
Main author: 
Karunakaran, Ananthan
IAA authors: 
Karunakaran, Ananthan
Authors: 
Karunakaran, Ananthan;Zaritsky, Dennis
Journal: 
Monthly Notices of the Royal Astronomical Society
Publication type: 
Article
Volume: 
519
Pages: 
884
Abstract: 
We extend the Ultra-Diffuse Galaxy (UDG) abundance relation, N<SUB>UDG</SUB> - M<SUB>200</SUB>, to lower halo mass hosts $(M_{200}\sim 10^{11.6-12.2}\, \mathrm{M}_{\odot })$. We select UDG satellites from published catalogues of dwarf satellite galaxies around Milky Way analogues, namely the Exploration of Local Volume Satellites (ELVES) survey, the Satellite Around Galactic Analogs (SAGA) survey, and a survey of Milky Way-like systems conducted using the Hyper-Suprime Cam. Of the 516 satellites around a total of 75 Milky Way-like hosts, we find that 41 satellites around 33 hosts satisfy the UDG criteria. The distributions of host halo masses peak around $M_{200}\sim 10^{12}\, \mathrm{M}_{\odot }$, independent of whether the host has a UDG satellite or not. We use literature UDG abundances and those derived here to trace the N<SUB>UDG</SUB> - M<SUB>200</SUB> relation over three orders of magnitude down to $M_{200}=10^{11.6}\, \mathrm{M}_{\odot }$ and find the best-fitting linear relation of $N_{\mathrm{ UDG}} = (38\pm 5) (\frac{M_{200}}{10^{14}})^{0.89\,\,\pm ~ 0.04}$. This sub-linear slope is consistent with earlier studies of UDG abundances as well as abundance relations for brighter dwarf galaxies, excluding UDG-formation mechanisms that require high-density environments. However, we highlight the need for further homogeneous characterization of UDGs across a wide range of environments to properly understand the N<SUB>UDG</SUB> - M<SUB>200</SUB> relation.
Database: 
ADS
URL: 
https://ui.adsabs.harvard.edu/#abs/2023MNRAS.519..884K/abstract
ADS Bibcode: 
2023MNRAS.519..884K
Keywords: 
galaxies: abundances;galaxies: dwarf;galaxies: evolution;galaxies: formation;Astrophysics - Astrophysics of Galaxies