TY - JOUR
T1 - The SAGA Survey. V. Modeling Satellite Systems around Milky Way-Mass Galaxies with Updated UniverseMachine
AU - Wang, Yunchong
AU - Nadler, Ethan O.
AU - Mao, Yao Yuan
AU - Wechsler, Risa H.
AU - Abel, Tom
AU - Behroozi, Peter
AU - Geha, Marla
AU - Asali, Yasmeen
AU - de los Reyes, Mithi A.C.
AU - Kado-Fong, Erin
AU - Kallivayalil, Nitya
AU - Tollerud, Erik J.
AU - Weiner, Benjamin
AU - Wu, John F.
N1 - Publisher Copyright:
© 2024. The Author(s). Published by the American Astronomical Society.
PY - 2024/11/1
Y1 - 2024/11/1
N2 - Environment plays a critical role in shaping the assembly of low-mass galaxies. Here, we use the UniverseMachine (UM) galaxy-halo connection framework and Data Release 3 of the Satellites Around Galactic Analogs (SAGA) Survey to place dwarf galaxy star formation and quenching into a cosmological context. UM is a data-driven forward model that flexibly parameterizes galaxy star formation rates (SFRs) using only halo mass and assembly history. We add a new quenching model to UM, tailored for galaxies with m ⋆ ≲ 109 M ⊙, and constrain the model down to m ⋆ ≳ 107 M ⊙ using new SAGA observations of 101 satellite systems around Milky Way (MW)-mass hosts and a sample of isolated field galaxies in a similar mass range from the Sloan Digital Sky Survey. The new best-fit model, “UM-SAGA,” reproduces the satellite stellar mass functions, average SFRs, and quenched fractions in SAGA satellites while keeping isolated dwarfs mostly star-forming. The enhanced quenching in satellites relative to isolated field galaxies leads the model to maximally rely on halo assembly to explain the observed environmental quenching. Extrapolating the model down to m ⋆ ∼ 106.5 M ⊙ yields a quenched fraction of ≳30% for isolated field galaxies and ≳80% for satellites of MW-mass hosts at this stellar mass. Spectroscopic surveys can soon test this specific prediction to reveal the relative importance of internal feedback, cessation of mass and gas accretion, satellite-specific gas processes, and reionization for the evolution of faint low-mass galaxies.
AB - Environment plays a critical role in shaping the assembly of low-mass galaxies. Here, we use the UniverseMachine (UM) galaxy-halo connection framework and Data Release 3 of the Satellites Around Galactic Analogs (SAGA) Survey to place dwarf galaxy star formation and quenching into a cosmological context. UM is a data-driven forward model that flexibly parameterizes galaxy star formation rates (SFRs) using only halo mass and assembly history. We add a new quenching model to UM, tailored for galaxies with m ⋆ ≲ 109 M ⊙, and constrain the model down to m ⋆ ≳ 107 M ⊙ using new SAGA observations of 101 satellite systems around Milky Way (MW)-mass hosts and a sample of isolated field galaxies in a similar mass range from the Sloan Digital Sky Survey. The new best-fit model, “UM-SAGA,” reproduces the satellite stellar mass functions, average SFRs, and quenched fractions in SAGA satellites while keeping isolated dwarfs mostly star-forming. The enhanced quenching in satellites relative to isolated field galaxies leads the model to maximally rely on halo assembly to explain the observed environmental quenching. Extrapolating the model down to m ⋆ ∼ 106.5 M ⊙ yields a quenched fraction of ≳30% for isolated field galaxies and ≳80% for satellites of MW-mass hosts at this stellar mass. Spectroscopic surveys can soon test this specific prediction to reveal the relative importance of internal feedback, cessation of mass and gas accretion, satellite-specific gas processes, and reionization for the evolution of faint low-mass galaxies.
UR - https://www.scopus.com/pages/publications/85210090965
UR - https://www.scopus.com/pages/publications/85210090965#tab=citedBy
U2 - 10.3847/1538-4357/ad7f4c
DO - 10.3847/1538-4357/ad7f4c
M3 - Article
AN - SCOPUS:85210090965
SN - 0004-637X
VL - 976
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1
M1 - 119
ER -