Mapping Accreted Stars in Early-Type Galaxies Across the Mass-Size Plane
arXiv:2108.06160 · doi:10.1093/mnras/stab2362
Abstract
Galaxy mergers are instrumental in dictating the final mass, structure, stellar populations, and kinematics of galaxies. Cosmological galaxy simulations indicate that the most massive galaxies at z=0 are dominated by high fractions of `ex-situ' stars, which formed first in distinct independent galaxies, and then subsequently merged into the host galaxy. Using spatially resolved MUSE spectroscopy we quantify and map the ex-situ stars in thirteen massive Early Type galaxies. We use full spectral fitting together with semi-analytic galaxy evolution models to isolate the signatures in the galaxies' light which are indicative of ex-situ populations. Using the large MUSE field of view we find that all galaxies display an increase in ex-situ fraction with radius, with massive and more extended galaxies showing a more rapid increase in radial ex-situ fraction, (reaching values between 30% to 100% at 2 effective radii) compared to less massive and more compact sources (reaching between 5% to 40% ex-situ fraction within the same radius). These results are in line with predictions from theory and simulations which suggest ex-situ fractions should increase significantly with radius at fixed mass for the most massive galaxies.
Accepted for publication in MNRAS
References in corpus (49)
- The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
- Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
- 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
- Too big to fail? The puzzling darkness of massive Milky Way subhaloes
- Improving the full spectrum fitting method: accurate convolution with Gauss-Hermite functions
- 3D-HST+CANDELS: The Evolution of the Galaxy Size-Mass Distribution since
- Properties of galaxies reproduced by a hydrodynamic simulation
- Introducing the Illustris Project: the evolution of galaxy populations across cosmic time
- Combined CO & Dust Scaling Relations of Depletion Time and Molecular Gas Fractions with Cosmic Time, Specific Star Formation Rate and Stellar Mass
- The Atlas3D project -- XXIX. The new look of early-type galaxies and surrounding fields disclosed by extremely deep optical images
- The Dual Origin of Stellar Halos
- Reconstructing the Subsurface Three-Dimensional Magnetic Structure of A Solar Active Region Using SDO/HMI Observations
- The MASSIVE Survey - I. A Volume-Limited Integral-Field Spectroscopic Study of the Most Massive Early-Type Galaxies within 108 Mpc
- SDSS-IV MaNGA: Spatially resolved star formation histories in galaxies as a function of galaxy mass and type
- Firefly (Fitting IteRativEly For Likelihood analYsis): a full spectral fitting code
- Building Late-Type Spiral Galaxies by In-Situ and Ex-Situ Star Formation
- Explaining the Color Distributions of Globular Cluster Systems in Elliptical Galaxies
- Intracluster light and the extended stellar envelopes of cD galaxies: An analytical description
- Stellar populations from spectroscopy of a large sample of quiescent galaxies at z > 1: Measuring the contribution of progenitor bias to early size growth
- SDSS-IV MaNGA: environmental dependence of stellar age and metallicity gradients in nearby galaxies
- The Diversity and Variability of Star Formation Histories in Models of Galaxy Evolution
- The Fornax 3D project: unveiling the thick disk origin in FCC 170: signs of accretion?
- The SAMI Galaxy Survey: Global stellar populations on the size-mass plane
- Energy equipartition between stellar and dark matter particles in cosmological simulations results in spurious growth of galaxy sizes
- Two new confirmed massive relic galaxies: red nuggets in the present-day Universe
- Optical IFU Observations of the Brightest Cluster Galaxy NGC 4696: The Case for a Minor Merger and Shock-excited Filaments
- An EAGLE's View of Ex-situ Galaxy Growth
- The information content of stellar halos: Stellar population gradients and accretion histories in early-type Illustris galaxies
- Evidence for the inside-out growth of the stellar mass distribution in galaxy clusters since z~1
- The Metallicity and Elemental Abundance Gradients of Simulated Galaxies, and their Environmental Dependence
- Comparison of Stellar Population Model Predictions Using Optical and Infrared Spectroscopy
- Tracing the outer halo in a giant elliptical to 25 Reff
- Clocking the formation of today's largest galaxies: Wide field integral spectroscopy of Brightest Cluster Galaxies and their surroundings
- The MASSIVE Survey - XII Connecting Stellar Populations of Early-Type Galaxies to Kinematics and Environment
- Abundance ratios and IMF slope in the dwarf elliptical galaxy NGC~1396 with MUSE
- The SAMI Galaxy Survey: stellar population gradients of central galaxies
- A discrete chemo-dynamical model of the giant elliptical galaxy NGC 5846: dark matter fraction, internal rotation and velocity anisotropy out to six effective radii
- Recovering stellar population parameters via different population models and stellar libraries
- Testing Stellar Population Fitting Ingredients with Globular Clusters I: Stellar Libraries
- New Constraints on Early-Type Galaxy Assembly from Spectroscopic Metallicities of Globular Clusters in M87
- A feather on the hat: Tracing the giant stellar stream around the Sombrero galaxy
- Recovering age-metallicity distributions from integrated spectra: validation with MUSE data of a nearby nuclear star cluster
- The assembly history of the nearest S0 galaxy NGC 3115 from its kinematics out to six half-light radii
- Exploring the AGN-Merger Connection in Arp 245 I: Nuclear Star Formation and Gas Outflow in NGC 2992
- First confirmed ultra-compact dwarf galaxy in the NGC 5044 group
- Unravelling the Origin of the Counter-Rotating Core in IC 1459 with KMOS and MUSE
- Old and New Major Mergers in the SOSIMPLE galaxy, NGC 7135
- Discovering novae in early-type galaxies with MUSE: A chance find in NGC 1404, and twelve more candidates from an archival search