Comparing the Quenching Times of Faint M31 and Milky Way Satellite Galaxies

Abstract

We present the star formation histories (SFHs) of 20 faint M31 satellites ($-12\lesssim M_V\lesssim -6$) that were measured by modeling sub-horizontal branch (HB) depth color-magnitude diagrams constructed from Hubble Space Telescope (HST) imaging. Reinforcing previous results, we find that virtually all galaxies quenched between 3 and 9 Gyr ago, independent of luminosity, with a notable concentration $3-6$ Gyr ago. This is in contrast to the Milky Way (MW) satellites, which are generally either faint with ancient quenching times or luminous with recent ($<3$ Gyr) quenching times. We suggest that systematic differences in the quenching times of M31 and MW satellites may be a reflection of the varying accretion histories of M31 and the MW. This result implies that the formation histories of low-mass satellites may not be broadly representative of low-mass galaxies in general. Among the M31 satellite population we identify two distinct groups based on their SFHs: one with exponentially declining SFHs ($\tau \sim 2$ Gyr) and one with rising SFHs with abrupt quenching. We speculate how these two groups could be related to scenarios for a recent major merger involving M31. The Cycle 27 HST Treasury survey of M31 satellites will provide well-constrained ancient SFHs to go along with the quenching times we measure here. The discovery and characterization of M31 satellites with $M_V\gtrsim -6$ would help quantify the relative contributions of reionization and environment to quenching of the lowest-mass satellites.

arXiv comment7 pages, 3 figures, 1 table. Submitted to ApJL and posted after addressing the referee's report. Comments welcome

References in corpus (46)

• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• On the variation of the Initial Mass Function
• PARSEC: stellar tracks and isochrones with the PAdova and TRieste Stellar Evolution Code
• MESA Isochrones and Stellar Tracks (MIST). I: Solar-Scaled Models
• The observed properties of dwarf galaxies in and around the Local Group
• The Dartmouth Stellar Evolution Database
• Small-Scale Challenges to the $\Lambda$CDM Paradigm
• WFPC2 Stellar Photometry with HSTphot
• Reionization and the abundance of galactic satellites
• Numerical Methods of Star Formation History Measurement and Applications to Seven Dwarf Spheroidals
• The Faintest Dwarf Galaxies
• A Vast Thin Plane of Co-rotating Dwarf Galaxies Orbiting the Andromeda Galaxy
• The Star Formation Histories of Local Group Dwarf Galaxies I. Hubble Space Telescope / Wide Field Planetary Camera 2 Observations
• The Effects of Photoionization on Galaxy Formation - II: Satellites in the Local Group
• The ACS Nearby Galaxy Survey Treasury VIII. The Global Star Formation Histories of 60 Dwarf Galaxies in the Local Volume
• The Updated BaSTI Stellar Evolution Models and Isochrones: I. Solar Scaled Calculations
• The ACS Nearby Galaxy Survey Treasury IX. Constraining asymptotic giant branch evolution with old metal-poor galaxies
• The Quenching of the Ultra-Faint Dwarf Galaxies in the Reionization Era
• Multi-Element Abundance Measurements from Medium-Resolution Spectra. III. Metallicity Distributions of Milky Way Dwarf Satellite Galaxies
• Gaia DR2 Proper Motions of Dwarf Galaxies within 420 kpc: Orbits, Milky Way Mass, Tidal Influences, Planar Alignments, and Group Infall
• The SAGA Survey: I. Satellite Galaxy Populations Around Eight Milky Way Analogs
• Formation Histories of Dwarf Galaxies in the Local Group
• The Panchromatic Hubble Andromeda Treasury X. Ultraviolet to Infrared Photometry of 117 Million Equidistant Stars
• The large-scale structure of the halo of the Andromeda galaxy II. Hierarchical structure in the Pan-Andromeda Archaeological Survey
• Structural parameters for the M31 dwarf spheroidals
• Gaia Proper Motions and Orbits of the Ultra-Faint Milky Way Satellites
• The ACS LCID Project: On the origin of dwarf galaxy types: a manifestation of the halo assembly bias?
• A 2-3 billion year old major merger paradigm for the Andromeda galaxy and its outskirts
• The Planes of Satellite Galaxies Problem, Suggested Solutions, and Open Questions
• The Andromeda galaxy's most important merger about 2 billion years ago as M32's likely progenitor
• The M31 Velocity Vector. I. Hubble Space Telescope Proper Motion Measurements
• The Star Formation Histories of Local Group Dwarf Galaxies III. Characterizing Quenching in Low-Mass Galaxies
• A Lonely Giant: The Sparse Satellite Population of M94 Challenges Galaxy Formation
• The ISLAndS project II: The Lifetime Star Formation Histories of Six Andromeda dSphs
• The Dwarf Spheroidal Companions to M31: WFPC2 Observations of Andromeda I
• The Leo-I group: new dwarf galaxy and UDG candidates
• The masses of Local Group dwarf spheroidal galaxies: The death of the universal mass profile
• From Galaxy Clusters to Ultra-Faint Dwarf Spheroidals: A Fundamental Curve Connecting Dispersion-supported Galaxies to Their Dark Matter Halos
• A Keck/DEIMOS spectroscopic survey of the faint M31 satellites And IX, And XI, And XII, and And XIII
• What Sets the Sizes of the Faintest Galaxies?
• The Spatially-Resolved Star Formation History of the M31 Outer Disc
• The ACS LCID project VII: the blue stragglers population in the isolated dSph galaxies Cetus and Tucana
• A Predicted Correlation Between Age Gradient and Star Formation History in FIRE Dwarf Galaxies
• Deep Photometry of Andromeda Reveals Striking Similarities in the Tidal Stream and Spheroid Populations
• Do halos that form early, have high concentration, are part of a pair, or contain a central galaxy potential host more pronounced planes of satellite galaxies?
• A rogues gallery of Andromeda's dwarf galaxies II. Precise Distances to 17 Faint Satellites

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• The Hubble Space Telescope Survey of M31 Satellite Galaxies I. RR Lyrae-based Distances and Refined 3D Geometric Structure
• Populations of double white dwarfs in Milky Way satellites and their detectability with LISA
• The cumulative star-formation histories of dwarf galaxies with TNG50. I: Environment-driven diversity and connection to quenching
• HST Proper Motions of NGC 147 and NGC 185: Orbital Histories and Test of Dynamically Coherent Andromeda Satellite Plane
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• Star Formation Histories of Ultra-Faint Dwarf Galaxies: environmental differences between Magellanic and non-Magellanic satellites?
• The SAGA Survey. III. A Census of 101 Satellite Systems around Milky Way-mass Galaxies
• GRUMPY: a simple framework for realistic forward-modelling of dwarf galaxies
• Milky Way Satellites Shining Bright in Gravitational Waves
• The infall of dwarf satellite galaxies are influenced by their host's massive accretions
• Satellites of Milky Way- and M31-like galaxies with TNG50: quenched fractions, gas content, and star formation histories
• Pegasus W: An Ultra-Faint Dwarf Galaxy Outside the Halo of M31 Not Quenched by Reionization
• Relating the Diverse Merger Histories and Satellite Populations of Nearby Galaxies
• The PAndAS View of the Andromeda Satellite System. IV Global properties
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• The SAGA Survey. V. Modeling Satellite Systems around Milky Way-mass Galaxies with Updated UniverseMachine
• Ultrafaint Dwarf Galaxy Candidates in the M81 Group: Signatures of Group Accretion
• Neutron-capture elements in dwarf galaxies III: A homogenized analysis of 13 dwarf spheroidal and ultra-faint galaxies
• Devouring the Milky Way Satellites: Modeling Dwarf Galaxies with Galacticus
• The Isaac Newton Telescope Monitoring Survey of Local Group Dwarf Galaxies. VI. The Star Formation History and Dust Production in Andromeda IX
• Predictions on the stellar-to-halo mass relation in the dwarf regime using the empirical model for galaxy formation EMERGE
• Spatial segregation impact on star formation in nearby dwarf spheroidal galaxies
• Andromeda XXV -- a dwarf galaxy with a low central dark matter density
• Mass Modeling the Andromeda Dwarf Galaxies: Andromeda VI and Andromeda XXIII
• A detailed star formation history for the extremely diffuse Andromeda XIX dwarf galaxy
• Kinematics and metallicity of the dwarf spheroidal galaxy Andromeda XVIII
• Star Formation Histories of Dwarf Spheroidal and Dwarf Elliptical Galaxies in the Local Universe
• Andromeda XXXV: The Faintest Dwarf Satellite of the Andromeda Galaxy
• Devouring The Centaurus A Satellites: Modeling Dwarf Galaxies with Galacticus
• The role of mass loss in constraining quenching time in dwarf galaxies from AGB and RGB star counts