The Hydra I cluster core. I. Stellar populations in the cD galaxy NGC 3311

Abstract

(Abridged for arXiv) The history of the mass assembly of brightest cluster galaxies may be studied by the mapping the stellar populations at large radial distances from the galaxy centre. We provide extended and robust measurements of the stellar population parameters in NGC 3311, the cD galaxy at the centre of the Hydra I cluster and out to three effective radii. Using seven absorption-features defined in the Lick/IDS system and single stellar populations models, we obtained luminosity-weighted ages, metallicities and alpha element abundances. The trends in the Lick indices and the distribution of the stellar population parameters indicate that the stars of NGC 3311 may be divided into two radial regimes, one within and the another beyond one effective radius, $R_e=8.4$ kpc, similar to the distinction between inner galaxy and external halo derived from the NGC 3311 velocity dispersion profile. The inner galaxy ($R\le R_e$) is old (age $\sim 14$ Gyr), have negative metallicity gradients and positive alpha element gradients. The external halo is also very old, but the metal and element abundances of the external halo have both a large scatter, indicating that stars from a variety of satellites with different masses have been accreted. The region in the extended halo associated with the off-centred envelope at 0${}^o$ < P.A.< 90${}^o$ (Arnaboldi et al. 2012) has higher metallicity with respect to the symmetric external halo. The different stellar populations in the inner galaxy and extended halo reflect the dominance of in situ stars in the former and the accreted origin for the large majority of the stars in the latter. These results provide supporting evidence to the recent theoretical models of formation of massive ellipticals as a two-phase process.

arXiv comment19 pages, 11 figures. Accepted for publication in A&A

References in corpus (63)

• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• The Origin of the Mass--Metallicity Relation: Insights from 53,000 Star-Forming Galaxies in the SDSS
• How Do Galaxies Get Their Gas?
• Parametric Recovery of Line-of-Sight Velocity Distributions from Absorption-Line Spectra of Galaxies via Penalized Likelihood
• Cold streams in early massive hot haloes as the main mode of galaxy formation
• The hierarchical formation of the brightest cluster galaxies
• The epochs of early-type galaxy formation as a function of environment
• MILES: A Medium resolution INT Library of Empirical Spectra
• 3D-HST+CANDELS: The Evolution of the Galaxy Size-Mass Distribution since $z=3$
• The ages and metallicities of galaxies in the local universe
• Minor mergers and the size evolution of elliptical galaxies
• The Chemical Evolution of the Galaxy: the two-infall model
• Stellar population models of Lick indices with variable element abundance ratios
• The GALEX Ultraviolet Atlas of Nearby Galaxies
• The Two Phases of Galaxy Formation
• Confirmation of the remarkable compactness of massive quiescent galaxies at z~2.3: early-type galaxies did not form in a simple monolithic collapse
• The Stellar Population Histories of Early-Type Galaxies. II. Controlling Parameters of the Stellar Populations
• Old Stellar Populations. VI. Absorption-Line Spectra of Galaxy Nuclei and Globular Clusters
• The MCXC: a Meta-Catalogue of X-ray detected Clusters of galaxies
• A Merger-Driven Scenario for Cosmological Disk Galaxy Formation
• The SAURON project - XVII. Stellar population analysis of the absorption line strength maps of 48 early-type galaxies
• Population Synthesis in the Blue IV: Accurate Model Predictions for Lick Indices and UBV Colors in Single Stellar Populations
• Intracluster Light in Nearby Galaxy Clusters: Relationship to the Halos of Brightest Cluster Galaxies
• GRAPE-SPH Chemodynamical Simulation of Elliptical Galaxies I: Evolution of Metallicity Gradients
• The Importance of Mergers for the Origin of Intracluster Stars in Cosmological Simulations of Galaxy Clusters
• Galactic accretion and the outer structure of galaxies in the CDM model
• Flux-calibrated stellar population models of Lick absorption-line indices with variable element abundance ratios
• The SAURON project - VI. Line strength maps of 48 elliptical and lenticular galaxies
• On the formation and physical properties of the Intra-Cluster Light in hierarchical galaxy formation models
• The Diffuse Light in Simulations of Galaxy Clusters
• On the interpretation of age and chemical composition of composite stellar populations determined with line-strength indices
• Early-type galaxies at large galactocentric radii - II. Metallicity gradients, and the [Z/H]--mass, [alpha/Fe]--mass relations
• The stellar accretion origin of stellar population gradients in massive galaxies at large radii
• SPIDER VII - Revealing the Stellar Population Content of Massive Early-type Galaxies out to 8Re
• The Stellar Halos of Massive Elliptical Galaxies II: Detailed Abundance Ratios at Large Radius
• Distinct core and halo stellar populations and the formation history of the bright Coma cluster early-type galaxy NGC 4889
• Abundance gradient slopes versus mass in spheroids: predictions by monolithic models
• The Cluster Velocity Dispersion of the Abell 2199 cD Halo of NGC 6166
• The early-type dwarf galaxy population of the Hydra I cluster
• The SLUGGS survey: Exploring the metallicity gradients of nearby early-type galaxies to large radii
• Spatially resolved kinematics and stellar populations of brightest cluster and group galaxies
• A tale of two tails and an off-centered envelope: diffuse light around the cD galaxy NGC 3311 in the Hydra I cluster
• The Kinematics of Intracluster Planetary Nebulae and the On-Going Subcluster Merger in the Coma Cluster Core
• The build-up of the cD halo of M87 - evidence for accretion in the last Gyr
• The Stellar Halos of Massive Elliptical Galaxies
• Stellar populations in the centres of brightest cluster galaxies
• The outer regions of the giant Virgo galaxy M87. Kinematic separation of stellar halo and intracluster light
• A large population of ultra-compact dwarf galaxies in the Hydra I cluster
• The formation of the [alpha/Fe] radial gradients in the stars of elliptical galaxies
• Stellar population and the origin of intra-cluster stars around brightest cluster galaxies: the case of NGC 3311
• The unmixed kinematics and origins of diffuse stellar light in the core of the Hydra I cluster (Abell 1060)
• Truncated Star Formation in Compact Groups of Galaxies: A Stellar Population Study
• Detailed XMM-Newton Observation of the Cluster of Galaxies Abell 1060
• The early-type galaxies NGC 1407 and NGC 1400 - II: star formation and chemical evolutionary history
• The outside-in formation of elliptical galaxies
• Age and metallicity gradients support hierarchical formation for M87
• Stellar Populations in the Outer Halo of the Massive Elliptical M49
• Inhomogeneity in the Hot Intracluster Medium of Abell 1060 Observed with Chandra
• Stellar population gradients in brightest cluster galaxies
• The accretion histories of brightest cluster galaxies from their stellar population gradients
• Metallicity and age gradients in round elliptical galaxies
• The dynamically hot stellar halo around NGC 3311: a small cluster-dominated central galaxy
• Kinematics and line strength indices in the halos of the Coma Brightest Cluster Galaxies NGC 4874 and NGC 4889

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• The Burrell Schmidt Deep Virgo Survey: Tidal Debris, Galaxy Halos, and Diffuse Intracluster Light in the Virgo Cluster
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• Massive galaxies on the road to quenching: ALMA observations of powerful high redshift radio galaxies
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• A Detection of the Environmental Dependence of the Sizes and Stellar Haloes of Massive Central Galaxies
• Sloshing in its cD halo: MUSE kinematics of the central galaxy NGC 3311
• Stellar Populations of BCGs, Close Companions and Intracluster Light in Abell 85, Abell 2457 and IIZw108
• In and out star formation in z~1.5 quiescent galaxies from rest-frame UV spectroscopy and the far-infrared
• A preserved high-z compact progenitor in the heart of NGC3311 revealed with MUSE 2D stellar population analysis
• The Hydra I cluster core - II. Kinematic complexity in a rising velocity dispersion profile around the cD galaxy NGC 3311
• Rapid build-up of the stellar content in the protocluster core SPT2349$-$56 at $z=4.3$
• Kinematics of the diffuse intragroup and intracluster light in groups and clusters of galaxies in the Local Universe within 100 Mpc distance
• What does (not) drive the variation of the low-mass end of the stellar initial mass function of early-type galaxies
• Young stellar population gradients in central cluster galaxies from NUV and optical spectroscopy
• Spectroscopic decomposition of the galaxy and halo of the cD galaxy NGC 3311
• Detection of the Stellar Intracluster Medium in Perseus (Abell 426)
• Dust and star formation in the centre of NGC 3311
• The Initial Mass Function and Other Stellar Properties Across the Core of the Hydra I Cluster
• Dark Energy Survey Year 6 Results: Intra-Cluster Light from Redshift 0.2 to 0.5