Early-type galaxies at intermediate redshift observed with HST WFC3: perspectives on recent star-formation

Abstract

We present an analysis of the stellar populations of 102 visually-selected early-type galaxies (ETGs) with spectroscopic redshifts (0.3<z<1.5) from observations in the Early Release Science program with the Wide Field Camera 3 (WFC3) on {\it Hubble Space Telescope} (HST). We fit one- and two-component synthetic stellar models to the ETGs UV-optical-near-IR spectral energy distributions and find a large fraction (~40%) are likely to have experienced a minor (f$\lesssim$10% of stellar mass) burst of recent (t$\lesssim$1 Gyr) star-formation. The measured ages and mass fraction of the young stellar populations do not strongly trend with measurements of galaxy morphology. We note that massive (log(M[$M_{\odot }$])>10.5) recently star-forming ETGs appear to have larger sizes. Furthermore, high-mass, quiescent ETGs identified with likely companions populate a distinct region in the size-mass parameter space, in comparison with the distribution of massive ETGs with evidence of RSF. We conclude that both mechanisms of the quenching of star-formation in disk-like ETGs and (gas-rich, minor) merger activity contribute to the formation of young stars and the size-mass evolution of intermediate redshift ETGs. The number of ETGs for which we have both HST WFC3 panchromatic (especially UV) imaging and spectroscopically-confirmed redshifts is relatively small, therefore a conclusion on the relative roles of both of these mechanisms remains an open question.

Accepted for publication in ApJ

References in corpus (85)

• Stellar population synthesis at the resolution of 2003
• Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Star Formation in Galaxies Along the Hubble Sequence
• The Dust Content and Opacity of Actively Star-Forming Galaxies
• Detailed Structural Decomposition of Galaxy Images
• Mass and environment as drivers of galaxy evolution in SDSS and zCOSMOS and the origin of the Schechter function
• The Cosmic Evolution Survey (COSMOS) -- Overview
• EAZY: A Fast, Public Photometric Redshift Code
• The Great Observatories Origins Deep Survey: Initial Results From Optical and Near-Infrared Imaging
• The epochs of early-type galaxy formation as a function of environment
• The Cosmic Baryon Budget
• The size distribution of galaxies in the Sloan Digital Sky Survey
• Galaxy Luminosity Functions to z~1: DEEP2 vs. COMBO-17 and Implications for Red Galaxy Formation
• Formation of Massive Galaxies at High Redshift: Cold Streams, Clumpy Disks and Compact Spheroids
• Minor mergers and the size evolution of elliptical galaxies
• Structure and Formation of Elliptical and Spheroidal Galaxies
• Passively Evolving Early-type Galaxies at 1.4<z<2.5 in the Hubble Ultra Deep Field
• 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 Green Valley is a Red Herring: Galaxy Zoo reveals two evolutionary pathways towards quenching of star formation in early- and late-type galaxies
• Old Stellar Populations. VI. Absorption-Line Spectra of Galaxy Nuclei and Globular Clusters
• The Stellar Population Histories of Local Early-Type Galaxies. I. Population Parameters
• The Stellar Populations and Evolution of Lyman Break Galaxies
• The SAURON project. II. Sample and early results
• The size evolution of galaxies since z~3: combining SDSS, GEMS and FIRES
• A Substantial Population of Low Mass Stars in Luminous Elliptical Galaxies
• Can Minor Merging Account for the Size Growth of Quiescent Galaxies? New Results from the CANDELS Survey
• The UV-optical Galaxy Color-Magnitude Diagram I: Basic Properties
• The Atlas3D project -- XIII. Mass and morphology of HI in early-type galaxies as a function of environment
• The On-Orbit Performance of the Galaxy Evolution Explorer
• Red Nuggets at z~1.5: Compact passive galaxies and the formation of the Kormendy Relation
• The Great Observatories Origins Deep Survey. VLT/FORS2 Spectroscopy in the GOODS-South Field: Part III
• GALEX UV Color-Magnitude Relations and Evidence for Recent Star Formation in Early-type Galaxies
• The UV-Optical Color Magnitude Diagram II: Physical Properties and Morphological Evolution On and Off of a Star-Forming Sequence
• The Y^2 Stellar Evolutionary Tracks
• The Hubble Space Telescope Wide Field Camera 3 Early Release Science data: Panchromatic Faint Object Counts for 0.2-2 microns wavelength
• Newly-quenched galaxies as the cause for the apparent evolution in average size of the population
• The evolving relations between size, mass, surface density, and star formation in 3x10^4 galaxies since z=2
• Far-Ultraviolet Radiation from Elliptical Galaxies
• Dissipation and Extra Light in Galactic Nuclei: II. 'Cusp' Ellipticals
• Compact High-Redshift Galaxies Are the Cores of the Most Massive Present-Day Spheroids
• The dramatic size evolution of elliptical galaxies and the quasar feedback
• The Majority of Compact Massive Galaxies at z~2 are Disk Dominated
• Constraints on galaxy formation from alpha-enhancement in luminous elliptical galaxies
• A binary model for the UV-upturn of elliptical galaxies (MNRAS version)
• The Importance of Dry and Mixed Mergers for Early-Type Galaxy Formation
• Photo-Chemical Evolution of Elliptical Galaxies I. The high-redshift formation scenario
• On Sizes, Kinematics, M/L Gradients, and Light Profiles of Massive Compact Galaxies at z~2
• E/S0 Galaxies on the Blue Color-Stellar Mass Sequence at z=0: Fading Mergers or Future Spirals?
• The ATLAS3D project - XVII. Linking photometric and kinematic signatures of stellar discs in early-type galaxies
• The importance of minor-merger-driven star formation and black-hole growth in disk galaxies
• The dominant role of mergers in the size evolution of massive early-type galaxies since z ~ 1
• Cosmic Evolution of Size and Velocity Dispersion for Early Type Galaxies
• The redshift evolution of early-type galaxies in COSMOS: Do massive early-type galaxies form by dry mergers?
• The relative abundance of compact and normal massive early-type galaxies and its evolution from redshift z~2 to the present
• Constraining The Assembly Of Normal And Compact Passively Evolving Galaxies From Redshift z=3 To The Present With CANDELS
• The Progenitors of the Compact Early-Type Galaxies at High-Redshift
• A coincidence of disturbed morphology and blue UV colour: minor-merger driven star formation in early-type galaxies at z~0.6
• The zCOSMOS 20k Group Catalog
• Galaxy-scale Star Formation on the Red Sequence: the Continued Growth of S0s and the Quiescence of Ellipticals
• The significant contribution of minor mergers to the cosmic star formation budget
• The UV Upturn in Elliptical Galaxies as an Age Indicator
• The UV colours of high-redshift early-type galaxies: evidence for recent star formation and stellar mass assembly over the last 8 billion years
• Destruction of Molecular Gas Reservoirs in Early-Type Galaxies by Active Galactic Nucleus Feedback
• The evolution of the number density of compact galaxies
• Better age estimations using UV-optical colours: breaking the age-metallicity degeneracy
• Galaxy Mergers at z>1 in the HUDF: Evidence for a Peak in the Major Merger Rate of Massive Galaxies
• The DEEP2 Galaxy Redshift Survey: Clustering Dependence on Galaxy Stellar Mass and Star Formation Rate at z~1
• On the Origin of the UV Upturn in Elliptical Galaxies. II. Test of the HB Hypothesis
• The insignificance of major mergers in driving star formation at z~2
• The UV Upturn in Elliptical galaxies and Environmental Effects
• Demography of SDSS early-type galaxies from the perspective of radial color gradients
• Puffing up early-type galaxies by baryonic mass loss: numerical experiments
• Star formation and figure rotation in the early-type galaxy NGC2974
• Sizes of Lyman-Alpha-Emitting Galaxies and Their Rest-Frame Ultraviolet Components at z=3.1
• Newborn spheroids at high redshift: when and how did the dominant, old stars in today's massive galaxies form?
• The Size Evolution of Passive Galaxies: Observations from the Wide Field Camera 3 Early Release Science Program
• Purely dry mergers do not explain the observed evolution of massive early-type galaxies since z = 1
• Probing the evolution of early-type cluster galaxies through chemical enrichment
• Spectro-photometric close pairs in GOODS-S: major and minor companions of intermediate-mass galaxies
• Galaxy environments over cosmic time: the non-evolving radial galaxy distributions around massive galaxies since z=1.6
• On the buildup of massive early-type galaxies at z<~1. I- Reconciling their hierarchical assembly with mass-downsizing
• HST/WFC3 Near-Infrared spectroscopy of quenched galaxies at z~1.5 from the WISP Survey: Stellar population properties
• Radio Continuum and Star Formation in CO-rich Early Type Galaxies
• A High Resolution Study of the Atomic Hydrogen in CO-Rich Early-Type Galaxies
• A Panchromatic Catalog of Early-Type Galaxies at Intermediate Redshift in the Hubble Space Telescope Wide Field Camera 3 Early Release Science Field

Cited by in corpus (6)

• A Preferential Growth Channel for Supermassive Black Holes in Elliptical Galaxies at z<2
• Structural analysis of star-forming blue early-type galaxies: Merger-driven star formation in elliptical galaxies
• Molecular Gas Reservoirs in Massive Quiescent Galaxies at $\mathrm{z}\sim 0.7$ Linked to Late Time Star Formation
• HST/WFC3 grism observations of $z\sim 1$ clusters: evidence for evolution in the mass-size relation of quiescent galaxies from poststarburst galaxies
• The role of quenching time in the evolution of the mass-size relation of passive galaxies from the WISP survey
• Recent star formation in 0.5<z<1.5 quiescent galaxies