Evolution in the Continuum Morphological Properties of Lyman-Alpha-Emitting Galaxies from z=3.1 to z=2.1

Abstract

We present a rest-frame ultraviolet morphological analysis of 108 z=2.1 Lyman Alpha Emitters (LAEs) in the Extended Chandra Deep Field South (ECDF-S) and compare it to a similar sample of 171 LAEs at z=3.1. Using Hubble Space Telescope (HST) images from the Galaxy Evolution from Morphology and SEDs survey, Great Observatories Origins Deep Survey, and Hubble Ultradeep Field, we measure size and photometric component distributions, where photometric components are defined as distinct clumps of UV-continuum emission. At both redshifts, the majority of LAEs have observed half-light radii <~ 2 kpc, but the median half-light radius rises from 1.0 kpc at z=3.1 to 1.4 kpc at z=2.1. A similar evolution is seen in the sizes of individual rest-UV components, but there is no evidence for evolution in the number of multi-component systems. In the z=2.1 sample, we see clear correlations between the size of an LAE and other physical properties derived from its SED. LAEs are found to be larger for galaxies with higher stellar mass, star formation rate, and dust obscuration, but there is no evidence for a trend between equivalent width and half-light radius at either redshift. The presence of these correlations suggests that a wide range of objects are being selected by LAE surveys at z~2, including a significant fraction of objects for which a massive and moderately extended population of old stars underlies the young starburst giving rise to the Lyman alpha emission.

21 pages, 19 figures, submitted to ApJ

References in corpus (11)

• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• The Hubble Ultra Deep Field
• Ly-alpha Emission-Line Galaxies at z = 3.1 in the Extended Chandra Deep Field South
• The Morphological Diversities Among Star-forming Galaxies at High Redshifts in the Great Observatories Origins Deep Survey (GOODS)
• The Evolution of Ly-alpha Emitting Galaxies Between z = 2.1 and z = 3.1
• Ly-alpha Emitting Galaxies at z = 2.1: Stellar Masses, Dust and Star Formation Histories from Spectral Energy Distribution Fitting
• SED fitting with Markov Chain Monte Carlo: Methodology and Application to z=3.1 Lyman Alpha Emitting Galaxies
• The UDF05 Follow-up of the HUDF: II. Constraints on Reionization from z-dropout Galaxies
• The nature of z ~ 2.3 Lyman-alpha emitters
• Evolution of Lyman Alpha Galaxies: Stellar Populations at z ~ 0.3
• Hubble Space Telescope Imaging of Lyman Alpha Emission at z=4.4

Cited by in corpus (32)

• The Evolution of Ly-alpha Emitting Galaxies Between z = 2.1 and z = 3.1
• The size-luminosity relation at z=7 in CANDELS and its implication on reionization
• The BOSS Emission-Line Lens Survey. IV. : Smooth Lens Models for the BELLS GALLERY Sample
• The HETDEX Pilot Survey V: The Physical Origin of Lyman-alpha Emitters Probed by Near-infrared Spectroscopy
• The BOSS Emission-Line Lens Survey. III. : Strong Lensing of Ly$\alpha$ Emitters by Individual Galaxies
• A Comprehensive Study of Ly$\alpha$ Emission in the High-redshift Galaxy Population
• Morphologies of ~190,000 Galaxies at z=0-10 Revealed with HST Legacy Data. III. Continuum Profile and Size Evolution of Lya Emitters
• On the UV compactness and morphologies of typical Lyman-a emitters from z~2 to z~6
• HST Emission Line Galaxies at z ~ 2: Comparing Physical Properties of Lyman Alpha and Optical Emission Line Selected Galaxies
• What is the Physical Origin of Strong Lya Emission? I. Demographics of Lya Emitter Structures
• Spectral Energy Distribution Fitting of HETDEX Pilot Survey Lyman-alpha Emitters in COSMOS and GOODS-N
• Searching for Neutral Hydrogen Halos around z ~ 2.1 and z ~ 3.1 Ly-alpha Emitting Galaxies
• SILVERRUSH. II. First Catalogs and Properties of ~2,000 Lya Emitters and Blobs at z~6-7 Identified over the 14-21 deg2 Sky
• The Spectrally Resolved Lyman-alpha Emission of Three Lyman-alpha Selected Field Galaxies at z~2.4 from the HETDEX Pilot Survey
• The Lyman alpha reference sample: IV. Morphology at low and high redshift
• Equivalent widths of Lyman $\alpha$ emitters in MUSE-Wide and MUSE-Deep
• To Stack or Not to Stack: Spectral Energy Distribution Properties of Lya-Emitting Galaxies at z=2.1
• Resolving on 100 pc scales the UV-continuum in Lyman-$\alpha$ emitters between redshift 2 to 3 with gravitational lensing
• J-PLUS: Unveiling the brightest-end of the Lyα luminosity function at 2.0<z<3.3 over 1000 deg^2
• Lyman Alpha and MgII as Probes of Galaxies and their Environments
• Magellan/MMIRS near-infrared multi-object spectroscopy of nebular emission from star forming galaxies at 2<z<3
• The Compact UV Size of Green Pea Galaxies As Local Analogs of High-redshift Ly$\alpha$-Emitters
• The BOSS Emission-Line Lens Survey V. Morphology and Substructure of Lensed Lyman-$\alpha$ Emitters at redshift $z\approx 2.5$ in the BELLS GALLERY
• Rest-frame UV Properties of Luminous Strong Gravitationally Lensed Ly$\alpha$ Emitters from the BELLS GALLERY Survey
• Morphological Properties of Lyman Alpha Emitters at Redshift 4.86 in the COSMOS Field: Clumpy Star Formation or Merger?
• Lyman-Alpha Escape from Low-Mass, Compact, High-Redshift Galaxies
• Similarities and uniqueness of Ly$\alpha$ emitters among star-forming galaxies at z=2.5
• The second Herschel-ATLAS Data Release - III: optical and near-infrared counterparts in the North Galactic Plane field
• Galaxies of the $z\sim 2$ Universe. I. Grism-Selected Rest-Frame Optical Emission Line Galaxies
• Spitzer's View of the Candidate Cluster and Protocluster Catalog (CCPC)
• Predicting the Merger Fraction of Lyman alpha Emitters from Redshift z~3 to z~7
• Can luminous Lyman alpha emitters at $z$ $\simeq$ 5.7 and $z$ $\simeq$ 6.6 suppress star formation?