LAGER Ly$\alpha$ Luminosity Function at $z\sim 7$, Implications for Reionization

Abstract

We present a new measurement of the Ly$\alpha$ luminosity function at redshift $z=6.9$, finding moderate evolution from $z=5.7$ that is consistent with a fully or largely ionized $z\sim 7$ intergalactic medium. Our result is based on four fields of the LAGER (Lyman Alpha Galaxies in the Epoch of Reionization) project. Our survey volume of $6.1\times 10^6$ Mpc${}^3$ is double that of the next largest $z\sim 7$ survey. We combine two new LAGER fields (WIDE12 and GAMA15A) with two previously reported LAGER fields (COSMOS and CDFS). In the new fields, we identify $N=95$ new $z=6.9$ Ly$\alpha$ emitters (LAEs); characterize our survey's completeness and reliability; and compute Ly$\alpha$ luminosity functions. The best-fit Schechter luminosity function parameters for all four LAGER fields are in good general agreement. Two fields (COSMOS and WIDE12) show evidence for a bright-end excess above the Schechter function fit. We find that the Ly$\alpha$ luminosity density declines at the same rate as the UV continuum LF from $z=5.7$ to $z=6.9$. This is consistent with an intergalactic medium that was fully ionized as early as redshift $z\sim 7$, or with a volume-averaged neutral hydrogen fraction of $x_{HI}<0.33$ at $1\sigma$.

arXiv comment19 pages, 11 figures; accepted by ApJ

References in corpus (76)

• Constraining the Evolution of the Ionizing Background and the Epoch of Reionization with z ~ 6 Quasars II: A Sample of 19 Quasars
• UV Luminosity Functions at redshifts z~4 to z~10: 10000 Galaxies from HST Legacy Fields
• The COSMOS2015 Catalog: Exploring the 1<z<6 Universe with half a million galaxies
• An 800-million-solar-mass black hole in a significantly neutral Universe at redshift 7.5
• The Hyper Suprime-Cam SSP Survey: Overview and Survey Design
• Cosmic Reionization and Early Star-Forming Galaxies: A Joint Analysis of New Constraints from Planck and Hubble Space Telescope
• The Evolution of the Galaxy Rest-Frame Ultraviolet Luminosity Function Over the First Two Billion Years
• Statistics of 207 Lya Emitters at a Redshift Near 7: Constraints on Reionization and Galaxy Formation Models
• The Subaru/XMM-Newton Deep Survey (SXDS). IV. Evolution of Lya Emitters from z=3.1 to 5.7 in the 1 deg^2 Field: Luminosity Functions and AGN
• The Hyper Suprime-Cam Software Pipeline
• An updated analytic model for the attenuation by the intergalactic medium
• A large Hα survey at z=2.23, 1.47, 0.84 & 0.40: the 11 Gyr evolution of star-forming galaxies from HiZELS
• The Universe is Reionizing at z~7: Bayesian Inference of the IGM Neutral Fraction Using Ly$\alpha$ Emission from Galaxies
• Ly-alpha Emission-Line Galaxies at z = 3.1 in the Extended Chandra Deep Field South
• Conditions for Reionizing the Universe with A Low Galaxy Ionizing Photon Escape Fraction
• Luminosity functions of Lyman-alpha emitters at z=6.5, and z=5.7: evidence against reionization at z=6
• Ly Alpha-Emitting Galaxies at z=3.1: L* Progenitors Experiencing Rapid Star Formation
• High-z Lyman-alpha Emitters. I. A Blank-Field Search for Objects Near Redshift z=3.4 in and around the Hubble Deep Field and the Hawaii Deep Field SSA22
• The Density of Lyman-alpha Emitters at Very High Redshift
• Rapid Reionization by the Oligarchs: The Case for Massive, UV-Bright, Star-Forming Galaxies with High Escape Fractions
• Large Equivalent width Lyman-alpha line emission at z=4.5: young galaxies in a young universe
• Extended Lyman alpha haloes around individual high-redshift galaxies revealed by MUSE
• The Multiwavelength Survey by Yale-Chile (MUSYC): Survey Design and Deep Public UBVRIz' Images and Catalogs of the Extended Hubble Deep Field South
• Large Lyman-alpha opacity fluctuations and low CMB tau in models of late reionization with large islands of neutral hydrogen extending to z<5.5
• A Rapidly Star-forming Galaxy 700 Million Years After the Big Bang at z=7.51
• First Results from the Large Area Lyman Alpha Survey
• Subaru Deep Survey II. Luminosity Functions and Clustering Properties of Lya Emitters at z=4.86 in the Subaru Deep Field
• Studying Reionization with Ly-alpha Emitters
• Systematic Identification of LAEs for Visible Exploration and Reionization Research Using Subaru HSC (SILVERRUSH). I. Program Strategy and Clustering Properties of ~2,000 Lya Emitters at z=6-7 over the 0.3-0.5 Gpc${}^2$ Survey Area
• An Atlas of z=5.7 and z=6.5 Ly alpha Emitters
• Rapid Decline of Lyman-alpha Emission Toward the Reionization Era
• The HETDEX Pilot Survey. II. The Evolution of the Ly-alpha Escape Fraction from the UV Slope and Luminosity Function of 1.9<z<3.8 LAEs
• Identification of the brightest Lyα emitters at z=6.6: implications for the evolution of the luminosity function in the re-ionisation era
• Accelerated Evolution of Ly$\alpha$ Luminosity Function at $\text{z}\gtrsim 7$ Revealed by the Subaru Ultra-Deep Survey for Ly$\alpha$ Emitters at $\text{z}=7.3$
• Constraints on reionisation from the z=7.5 QSO ULASJ1342+0928
• Are we witnessing the epoch of reionisation at $z=7.1$ from the spectrum of J1120+0641?
• First Results from the Lyman Alpha Galaxies in the Epoch of Reionization (LAGER) Survey: Cosmological Reionization at z ~ 7
• The First Systematic Survey for Lyman Alpha Emitters at z=7.3 with Red-sensitive Subaru/Suprime-Cam
• Texas Spectroscopic Search for Ly$\alpha$ Emission at the End of Reionization III. the Ly$\alpha$ Equivalent-width Distribution and Ionized Structures at $z>7$
• An overdensity of galaxies at z=5.9 +/-0.2 in the Ultra Deep Field confirmed using the ACS grism
• The bright-star masks for the HSC-SSP survey
• The Effects of Reionization on Lyman-alpha Galaxy Surveys
• Bright and Faint Ends of Ly$\alpha$ Luminosity Functions at $\text{z}=2$ Determined by the Subaru Survey: Implications for AGN, Magnification Bias, and ISM HI Evolution
• Lyα emission line reconstruction for high-$z$ QSOs
• On Near-Infrared H-Alpha Searches for High-Redshift Galaxies
• The Lyman-alpha luminosity function at z=5.7-6.6 and the steep drop of the faint end: implications for reionization
• Luminosity Functions of Lyman Alpha Emitting Galaxies and Cosmic Reionization of Hydrogen
• First spectroscopic measurements of [OIII] emission from Lyman-alpha selected field galaxies at z ~ 3.1
• The MUSE Hubble Ultra Deep Field Survey VI: The Faint-End of the Lya Luminosity Function at 2.91 < z < 6.64 and Implications for Reionisation
• Lyman alpha emitting galaxies at 0.2 < z < 0.35 from GALEX spectroscopy
• Onset of Cosmic Reionization: Evidence of An Ionized Bubble Merely 680 Myrs after the Big Bang
• The Volume Fraction of Ionized Intergalactic Gas at Redshift z=6.5
• The Size Evolution of Star-forming Galaxies Since z~7 Using ZFOURGE
• A New Constraint on Reionization from Evolution of the Ly$\alpha$ Luminosity Function at $z\sim 6-7$ Probed by a Deep Census of $z=7.0$ Ly$\alpha$ Emitter Candidates to 0.3 $L^{\ast }$
• SILVERRUSH. VI. A simulation of Ly$\alpha$ emitters in the reionization epoch and a comparison with Subaru Hyper Suprime-Cam survey early data
• Ly alpha emitting galaxies as early stages in galaxy formation
• Physical Properties of Spectroscopically-Confirmed Galaxies at z >= 6. I. Basic Characteristics of the Rest-Frame UV Continuum and Lyman-alpha emission
• The MUSE-Wide Survey: A determination of the Lyman $\alpha$ emitter luminosity function at $3<z<6$
• A Lyman-α protocluster at redshift 6.9
• Morphologies of ~190,000 Galaxies at z=0-10 Revealed with HST Legacy Data. III. Continuum Profile and Size Evolution of Lya Emitters
• The Ly$\alpha$ Luminosity Function and Cosmic Reionization at $z\sim$ 7.0: a Tale of Two LAGER Fields
• CHORUS II. Subaru/HSC Determination of the Ly$\alpha$ Luminosity Function at $z=7.0$: Constraints on Cosmic Reionization Model Parameter
• First results from Faint Infrared Grism Survey (FIGS): first simultaneous detection of Lyman-alpha emission and Lyman break from a galaxy at z=7.51
• First Spectroscopic Confirmations of z ~ 7.0 Lya Emitting Galaxies in the LAGER Survey
• Studying reionization with the next generation of Ly-alpha emitter surveys
• Implementation of robust image artifact removal in SWarp through clipped mean stacking
• Spectroscopic Confirmation of Faint Lyman Break Galaxies at Redshifts Four and Five in the Hubble Ultra Deep Field
• Discovery of a z = 7.452 High Equivalent Width Lyman-α Emitter from the Hubble Space Telescope Faint Infrared Grism Survey
• A Faint Flux-Limited Lyman Alpha Emitter Sample at $z\sim 0.3$
• The Ultraluminous Lyman Alpha Luminosity Function at z=6.6
• The Faint-End Slope of the Redshift 5.7 Lyman Alpha Luminosity Function
• An Extremely Deep Wide-Field Near-Infrared Survey: Bright Galaxy Counts and Local Large Scale Structure
• A large, deep 3 deg${}^2$ survey of H$\alpha$, [OIII], and [OII] emitters from LAGER: constraining luminosity functions
• The Spitzer-HETDEX Exploratory Large Area Survey II: Dark Energy Camera and Spitzer/IRAC Multiwavelength Catalog
• A Lyman Break Galaxy in the Epoch of Reionization from HST Grism Spectroscopy
• Design for the First Narrowband Filter for the Dark Energy Camera: Optimizing the LAGER Survey for z ~ 7 Galaxies

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• A lack of LAEs within 5Mpc of a luminous quasar in an overdensity at z=6.9: potential evidence of quasar negative feedback at protocluster scales
• The Impact of Cosmic Variance on Inferences of Global Neutral Fraction Derived from Ly$\alpha$ Luminosity Functions During Reionization
• Introducing the Texas Euclid Survey for Lyman Alpha (TESLA) Survey: Initial Study Correlating Galaxy Properties to Lyman-Alpha Emission
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• A fast method of reionization parameter space exploration using GPR trained SCRIPT
• Studying the Multi-frequency Angular Power Spectrum of the Cosmic Dawn 21-cm Signal
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• Global 21 cm signal: a promising probe of primordial features
• A resolved Lyman-Alpha profile with doubly peaked emission at z~7
• Measuring the IGM correlation length at 5<z<6.1: a fast change at the end of Reionization
• Constraints on the Epoch of Reionization with Roman Space Telescope and the Void Probability Function of Lyman-Alpha Emitters
• Deep JWST spectroscopy of galaxies in a candidate ionized bubble at $z=8.7$: probing reionization at pMpc scales with Ly$\alpha$ emission
• Double-Peaked Ly$\alpha$ Emission during Reionization Requires Nearby Voids and a Favorable Local Ionizing Background
• Far-infrared observations of dust in Ly$\alpha$ emitters at z=2-6
• Uncertainty-Aware Neural Networks for Fuzzy Dark Matter Model Selection from \texorpdfstring{$x_{\mathrm{HI}}$}{x_HI} Measurements