Year: 2026
Type: article
Abstract: We present the first results of the ongoing Identifying Dwarfs of Magellanic Cloud Analog GalaxiEs (ID-MAGE) survey. This includes new velocities of 78 satellite candidates identified around 35 nearby LMC- and SMC-mass hosts ( D = 4–10 Mpc). Using new Green Bank Telescope H i observations, new optical long-slit spectroscopy from SALT and MDM 2.4 m, and Dark Energy Spectroscopic Instrument DR1, we find six are velocity-confirmed satellite galaxies (6.5 × 10 5 ≤ M ⋆ / M ⊙ ≤ 1.5 × 10 7 ) and 72 are background galaxies. Our results underscore the ability of spectroscopic follow-up to effectively separate satellites from background galaxies. Including the six newly velocity-confirmed satellites and the 19 satellites confirmed in the literature, the ID-MAGE hosts have a combined total of 25 confirmed satellites. This confirmed satellite sample includes the complete satellite populations of three hosts (UGC 04426: zero satellites; UGC 08201: zero satellites; NGC 3432: four satellites), which we compare to simulations and known satellite systems from previous systematic searches around low-mass hosts. Our confirmed satellite sample is nearly complete for the most massive satellites ( M ⋆ > 10 7 M ⊙ ). We find these satellites have a quenched fraction of 10%–25%, placing them between the <5% quenched fraction of isolated galaxies and the 40%–70% quenched fraction of Milky Way–analog satellites in the same stellar mass range (10 7 M ⊙ < M ⋆ < 10 8 M ⊙ ). This demonstrates the impact that low-mass galaxies have on the evolution of their satellites.
Source: The Astrophysical Journal
Authors: Laura Congreve Hunter, Burçin Mutlu-Pakdil, Michael B. Farnell, David J. Sand, Kristine Spekkens, Paul Bennet, Sasha N. Campana, Jeffrey L. Carlin, Denija Crnojević, Amandine Doliva-Dolinsky, Emmanuel Durodola, Michael G. Jones, Donghyeon J. Khim, Laurella Marin, Ricardo J. Mendez, Deepthi S. Prabhu, Dennis Zaritsky
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Funders: National Science Foundation, U.S. Department of Energy, National Aeronautics and Space Administration, California Institute of Technology, Jet Propulsion Laboratory, Natural Sciences and Engineering Research Council of Canada, Science and Technology Facilities Council, Lawrence Berkeley National Laboratory
Awards: Collaborative Research: AI-Powered Discovery of The Faintest Galaxies: Pushing the Galaxy Formation Frontier, Collaborative Research: AI-Powered Discovery of The Faintest Galaxies: Pushing the Galaxy Formation Frontier, Collaborative Research: AI-Powered Discovery of The Faintest Galaxies: Pushing the Galaxy Formation Frontier, Understanding the diversity of low mass galaxies, Collaborative Research: Dwarf Galaxies Over Cosmic Time
OpenAlex ID: W7139950815