The age gradients of galaxies in EAGLE: outside-in quenching as the origin of young bulges in cluster galaxies

Abstract

Many disc galaxies in clusters have been found with bulges of similar age or younger than their surrounding discs, at odds with field galaxies of similar morphology and their expected inside-out formation. We use the EAGLE simulations to test potential origins for this difference in field and cluster galaxies. We find, in agreement with observations, that on average disc-dominated field galaxies in the simulations have older inner regions, while similar galaxies in groups and clusters have similarly aged or younger inner regions. This environmental difference is a result of outside-in quenching of the cluster galaxies. Prior to group/cluster infall, galaxies of a given present-day mass and morphology exhibit a similar evolution in their specific star formation rate (sSFR) profiles. Post-infall, the outer sSFRs of group and cluster galaxies significantly decrease due to interstellar medium stripping, while the central sSFR remains similar to field galaxies. Field disc galaxies instead generally retain radially increasing sSFR profiles. Thus, field galaxies continue to develop negative age gradients (younger discs), while cluster galaxies instead develop positive age gradients (younger bulges).

14 pages, 11 figures. Accepted for publication in MNRAS

References in corpus (29)

• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• The propagation of uncertainties in stellar population synthesis modeling I: The relevance of uncertain aspects of stellar evolution and the IMF to the derived physical properties of galaxies
• The EAGLE simulations of galaxy formation: calibration of subgrid physics and model variations
• Size evolution of the most massive galaxies at 1.7<z<3 from GOODS NICMOS survey imaging
• Evidence for Mature Bulges and an Inside-out Quenching Phase 3 Billion Years After the Big Bang
• Reconstructing the Subsurface Three-Dimensional Magnetic Structure of A Solar Active Region Using SDO/HMI Observations
• Specific SFR profiles in nearby spiral galaxies: quantifying the inside-out formation of disks
• SDSS-IV MaNGA: Spatially resolved star formation histories in galaxies as a function of galaxy mass and type
• A chronicle of galaxy mass assembly in the EAGLE simulation
• The SAMI Galaxy Survey: Spatially resolving the environmental quenching of star formation in GAMA galaxies
• Spatially Resolved Star Formation and Inside-out Quenching in the TNG50 Simulation and 3D-HST Observations
• The GALEX Arecibo SDSS survey: III. Evidence for the Inside-Out Formation of Galactic Disks
• Energy equipartition between stellar and dark matter particles in cosmological simulations results in spurious growth of galaxy sizes
• The spatially resolved star formation history of CALIFA galaxies: Cosmic time scales
• The SAMI Galaxy Survey: Quenching of star formation in clusters I. Transition galaxies
• Spurious heating of stellar motions in simulated galactic disks by dark matter halo particles
• An EAGLE's View of Ex-situ Galaxy Growth
• The Origin of S0s in Clusters: evidence from the bulge and disc star formation histories
• UVI colour gradients of 0.4<z<1.4 star-forming main sequence galaxies in CANDELS: dust extinction and star formation profiles
• The diverse nature and formation paths of slow rotator galaxies in the EAGLE simulations
• The SAMI Galaxy Survey: A Range in S0 Properties Indicating Multiple Formation Pathways
• Satellite Quenching, Galaxy Inner Density and the Halo Environment
• Galaxy properties as revealed by MaNGA. III. Kinematic profiles and stellar population gradients in S0s
• HST/WFC3 grism observations of $z\sim 1$ clusters: Evidence for rapid outside-in environmental quenching from spatially resolved H$\alpha$ maps
• The Origins of UV-optical Color Gradients in Star-forming Galaxies at z ~ 2: Predominant Dust Gradients But Negligible sSFR Gradients
• The continuous rise of bulges out of galactic disks
• The SAMI Galaxy Survey: bulge and disk stellar population properties in cluster galaxies
• Formation of S0s in extreme environments II: the star-formation histories of bulges, discs and lenses
• Age bimodality in the central region of pseudobulges in S0 galaxies

Cited by in corpus (8)

• The galaxy morphology-density relation in the EAGLE simulation
• The Fornax3D project: Environmental effects on the assembly of dynamically cold disks in Fornax cluster galaxies
• BUDDI-MaNGA II: The Star-Formation Histories of Bulges and Discs of S0s
• Bulge formation inside quiescent lopsided stellar disks: connecting accretion, star formation and morphological transformation in a z ~ 3 galaxy group
• Colour gradients of low-redshift galaxies in the DESI Legacy Imaging Survey
• The AGORA High-resolution Galaxy Simulations Comparison Project. VIII: Disk Formation and Evolution of Simulated Milky Way Mass Galaxy Progenitors at $1<z<5$
• From naked spheroids to disky galaxies: how do massive disk galaxies shape their morphology?
• Independent Evidence for earlier formation epochs of fossil groups of galaxies through the intracluster light: the case for RX J100742.53+380046.6