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arXiv · 2504.08030

ELVES-Dwarf I: Satellites Systems of Eight Isolated Dwarf Galaxies in the Local Volume

Jiaxuan Li·Jenny E. Greene·Shany Danieli·Scott G. Carlsten·Marla Geha·Fangzhou Jiang·Masayuki Tanaka
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Abstract

The satellite populations of Milky Way--mass systems have been extensively studied, significantly advancing our understanding of galaxy formation and dark matter physics. In contrast, the satellites of lower-mass dwarf galaxies remain largely unexplored, despite hierarchical structure formation predicting that dwarf galaxies should host their own satellites. We present the first results of the ELVES-Dwarf survey, which aims to statistically characterize the satellite populations of isolated dwarf galaxies in the Local Volume ($4<D<10$~Mpc). We identify satellite candidates in integrated light using the Legacy Surveys data and are complete down to $M_g\approx -9$ mag. We then confirm the association of satellite candidates with host galaxies using surface brightness fluctuation distances measured from the Hyper Suprime-Cam data. We surveyed 8 isolated dwarf galaxies with stellar masses ranging from sub-Small Magellanic Cloud to Large Magellanic Cloud scales ($10^{7.8} < M_\star^{\rm host}<10^{9.5}\, M_\odot$) and confirmed 6 satellites with stellar masses between $10^{5.6}$ and $10^{8} \, M_\odot$. Most confirmed satellites are star-forming, contrasting with the primarily quiescent satellites observed around Milky Way--mass hosts. By comparing observed satellite abundances and stellar mass functions with theoretical predictions, we find no evidence of a "missing satellite problem" in the dwarf galaxy regime.

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Jiaxuan Li, Jenny E. Greene, Shany Danieli, Scott G. Carlsten, Marla Geha, Fangzhou Jiang, Masayuki Tanaka. 2025-04-10. ELVES-Dwarf I: Satellites Systems of Eight Isolated Dwarf Galaxies in the Local Volume. https://arxiv.org/abs/2504.08030

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