2021/02/08 by T. C. Scott, Chandreyee Sengupta, P. Lagos +2 · 1 citation
Physics and Astronomy · #Astronomy #Astrophysics #Astrophysics and Cosmic Phenomena #Cluster (spacecraft) #Dark matter #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy cluster #Giant Metrewave Radio Telescope #Physics #RADIUS #Radio Astronomy Observations and Technology #Radio galaxy #Spectroscopy #astro-ph.GA
paper · pdf · doi:10.1093/mnras/stab390
13 pages , 8 Figures
arxiv created 2021/02/08 · openalex publication_date 2021/02/10 · openalex created_date 2021/02/15 · arxiv updated 2021/02/17 · openalex updated_date 2026/08/05
ABSTRACT We report on the first resolved H i observations of two blue ultra-diffuse galaxies (UDGs), using the Giant Metrewave Radio Telescope (GMRT). These observations add to the so-far limited number of UDGs with resolved H i data. The targets are from contrasting non-cluster environments: UDG-B1 is projected in the outskirts of Hickson Compact Group 25 and Secco-dI-2 (SdI-2) is an isolated UDG. These UDGs also have contrasting effective radii with Re of 3.7 kpc (similar to the Milky Way) and 1.3 kpc, respectively. SdI-2 has an unusually large \fracM_\rm H \small IM_* ratio = 28.9, confirming a previous single dish H i observation. Both galaxies display H i morphological and kinematic signatures consistent with a recent tidal interaction, which is also supported by observations from other wavelengths, including optical spectroscopy. Within the limits of the observations’ resolution our analysis indicates that SdI-2 is dark matter dominated within its H i radius and this is also likely to be the case for UDG-B1. Our study highlights the importance of high spatial and spectral resolution H i observations for the study of the dark matter properties of UDGs.