ID-MAGE. II. The Star-forming Satellites of Low-mass Hosts
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.
Authors
- S. Campana (ORCID: https://orcid.org/0009-0007-9488-7050)
- Dennis Zaritsky (ORCID: https://orcid.org/0000-0002-5177-727X)
- Emmanuel Durodola (ORCID: https://orcid.org/0009-0004-9516-9593)
- Michael G. Jones (ORCID: https://orcid.org/0000-0002-3628-4370)
- Denija Crnojević (ORCID: https://orcid.org/0000-0002-1763-4128)
- Heidi Jo Newberg (ORCID: https://orcid.org/0000-0001-8348-0983)
- Donghyeon J. Khim (ORCID: https://orcid.org/0000-0002-7013-4392)
- Paul Bennet (ORCID: https://orcid.org/0000-0001-8354-7279)
- Kristine Spekkens (ORCID: https://orcid.org/0000-0002-0956-7949)
- Deepthi S. Prabhu (ORCID: https://orcid.org/0000-0002-8217-5626)
- Burçı̇n Mutlu-Pakdı̇l (ORCID: https://orcid.org/0000-0001-9649-4815)
- David J. Sand (ORCID: https://orcid.org/0000-0003-4102-380X)
- Amandine Doliva-Dolinsky (ORCID: https://orcid.org/0000-0001-9775-9029)
- Laurella C. Marin (ORCID: https://orcid.org/0009-0008-3389-9848)
- Laura E. Hunter (ORCID: https://orcid.org/0000-0001-5368-3632)
- Michael B. Farnell (ORCID: https://orcid.org/0009-0001-8573-1800)
- Ricardo J. Mendez (ORCID: https://orcid.org/0009-0004-9126-8260)
Institutions
- Dartmouth College (US)
- Space Telescope Science Institute (US)
- University of Arizona (US)
- University of Washington (US)
- Queen's University (CA)
- University of Surrey (GB)
- Queens University (BD)
- Infrared Processing and Analysis Center (US)
- University of Tampa (US)
Publication Details
- Journal
- The Astrophysical Journal
- Published
- 2026-11-06
- DOI
- https://doi.org/10.3847/1538-4357/aeacd4
- Citations
- 4
- Primary Topic
- Galaxies: Formation, Evolution, Phenomena
- Type
- article
- Field-Weighted Citation Impact
- 3.33
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