Observations of Ly$\alpha$ Emitters at High Redshift

Abstract

In this series of lectures, I review our observational understanding of high-$z$ Ly$\alpha$ emitters (LAEs) and relevant scientific topics. Since the discovery of LAEs in the late 1990s, more than ten (one) thousand(s) of LAEs have been identified photometrically (spectroscopically) at $z\sim 0$ to $z\sim 10$. These large samples of LAEs are useful to address two major astrophysical issues, galaxy formation and cosmic reionization. Statistical studies have revealed the general picture of LAEs' physical properties: young stellar populations, remarkable luminosity function evolutions, compact morphologies, highly ionized inter-stellar media (ISM) with low metal/dust contents, low masses of dark-matter halos. Typical LAEs represent low-mass high-$z$ galaxies, high-$z$ analogs of dwarf galaxies, some of which are thought to be candidates of population III galaxies. These observational studies have also pinpointed rare bright Ly$\alpha$ sources extended over $\sim 10-100$ kpc, dubbed Ly$\alpha$ blobs, whose physical origins are under debate. LAEs are used as probes of cosmic reionization history through the Ly$\alpha$ damping wing absorption given by the neutral hydrogen of the inter-galactic medium (IGM), which complement the cosmic microwave background radiation and 21cm observations. The low-mass and highly-ionized population of LAEs can be major sources of cosmic reionization. The budget of ionizing photons for cosmic reionization has been constrained, although there remain large observational uncertainties in the parameters. Beyond galaxy formation and cosmic reionization, several new usages of LAEs for science frontiers have been suggested such as the distribution of {\sc Hi} gas in the circum-galactic medium and filaments of large-scale structures. On-going programs and future telescope projects, such as JWST, ELTs, and SKA, will push the horizons of the science frontiers.

Lecture notes for `Lyman-alpha as an Astrophysical and Cosmological Tool', Saas-Fee Advanced Course 46. Verhamme, A., North, P., Cantalupo, S., & Atek, H. (eds.) --- 147 pages, 103 figures. Abstract abridged. Link to the lecture program including the video recording and ppt files : https://obswww.unige.ch/Courses/saas-fee-2016/program.cgi

References in corpus (72)

• Cosmic Star Formation History
• Cold streams in early massive hot haloes as the main mode of galaxy formation
• A luminous quasar at a redshift of z = 7.085
• A Highly Consistent Framework for the Evolution of the Star-Forming "Main Sequence" from z~0-6
• UV Luminosity Functions at redshifts z~4 to z~10: 10000 Galaxies from HST Legacy Fields
• An Observational Determination of the Bolometric Quasar Luminosity Function
• Binary Population and Spectral Synthesis Version 2.1: construction, observational verification and new results
• Cosmic Reionization and Early Star-Forming Galaxies: A Joint Analysis of New Constraints from Planck and Hubble Space Telescope
• The MUSE second-generation VLT instrument
• Constraining the Low-Mass Slope of the Star Formation Sequence at 0.5<z<2.5
• Observational constraints on Cosmic Reionization
• Strong Nebular Line Ratios in the Spectra of z~2-3 Star-forming Galaxies: First Results from KBSS-MOSFIRE
• 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
• 3D Lyman-alpha radiation transfer. I. Understanding Lyman-alpha line profile morphologies
• Subaru Deep Survey V. A Census of Lyman Break Galaxies at z=4 and 5 in the Subaru Deep Fields: Photometric Properties
• The End of the Reionization Epoch Probed by Ly-alpha Emitters at z=6.5 in the Subaru Deep Field
• A dusty, normal galaxy in the epoch of reionization
• The observed ionization rate of the intergalactic medium and the ionizing emissivity at z >5: Evidence for a photon starved and extended epoch of reionization
• Ly-alpha Emission-Line Galaxies at z = 3.1 in the Extended Chandra Deep Field South
• The MUSE Hubble Ultra Deep Field Survey: I. Survey description, data reduction and source detection
• Faint AGNs at z>4 in the CANDELS GOODS-S field: looking for contributors to the reionization of the Universe
• The Direct Detection of Lyman-Continuum Emission from Star-forming Galaxies at z~3
• A massive proto-cluster of galaxies at a redshift of z {\approx} 5.3
• A galaxy at a redshift z = 6.96
• Line Emitting Galaxies Beyond a Redshift of 7: An Improved Method for Estimating the Evolving Neutrality of the Intergalactic Medium
• New observations of z~7 galaxies: evidence for a patchy reionization
• Studying Reionization with Ly-alpha Emitters
• Keeping the Universe ionised: Photo-heating and the clumping factor of the high-redshift intergalactic medium
• A Spectroscopic Redshift Measurement for a Luminous Lyman Break Galaxy at z=7.730 using Keck/MOSFIRE
• The MUSE 3D view of the Hubble Deep Field South
• Ultraviolet Emission Lines in Young Low Mass Galaxies at z~2: Physical Properties and Implications for Studies at z>7
• Spectroscopic detections of CIII]1909 at z~6-7: A new probe of early star forming galaxies and cosmic reionisation
• A Local Clue to the Reionization of the Universe
• The Ly-alpha Properties of Faint Galaxies at z2-3 with Systemic Redshifts and Velocity Dispersions from Keck-MOSFIRE
• Super-luminous supernovae at redshifts of 2.05 and 3.90
• Hubble Frontier Fields First Complete Cluster Data: Faint Galaxies at $z\sim 5-10$ for UV Luminosity Functions and Cosmic Reionization
• Accelerated Evolution of Ly$\alpha$ Luminosity Function at $\text{z}\gtrsim 7$ Revealed by the Subaru Ultra-Deep Survey for Ly$\alpha$ Emitters at $\text{z}=7.3$
• The Impact of The IGM on High-Redshift Lyman Alpha Emission Lines
• New redshift z ~ 9 galaxies in the Hubble Frontier Fields: Implications for early evolution of the UV luminosity density
• Detecting the Rise and Fall of 21 cm Fluctuations with the Murchison Widefield Array
• New Constraints on the Faint-end of the UV Luminosity Function at z~7-8 using the Gravitational Lensing of the Hubble Frontier Fields Cluster A2744
• Tracing the reionization epoch with ALMA: [CII] emission in z~7 galaxies
• Diffuse Lyman-alpha Halos around Galaxies at z=2.2-6.6: Implications for Galaxy Formation and Cosmic Reionization
• Prime Focus Spectrograph (PFS) for the Subaru Telescope: Overview, recent progress, and future perspectives
• The Lyman alpha Reference Sample: Extended Lyman alpha Halos Produced at Low Dust Content
• Definitive Identification of the Transition between Small- to Large-Scale Clustering for Lyman Break Galaxies
• The Chandra Deep Protocluster Survey: Ly-alpha Blobs are powered by heating, not cooling
• The Lyman-alpha Reference Sample: I. Survey outline and first results for Markarian 259
• Frontier Fields: High-Redshift Predictions and Early Results
• Probing Reionization with the 21 cm-Galaxy Cross Power Spectrum
• A Luminosity Function of Lyman Alpha Emitting Galaxies at Redshift 4.5
• A spectroscopic search for AGN activity in the reionization era
• ALMA Observation of 158 micron [CII] Line and Dust Continuum of a z=7 Normally Star-forming Galaxy in the Epoch of Reionization
• Effects of Dust Geometry in Lyman Alpha Galaxies at z = 4.4
• Deficiency of large equivalent width Lyman-alpha emission in luminous Lyman break galaxies at z~5-6?
• ALMA reveals metals yet no dust within multiple components in CR7
• Lyman-alpha Forest Tomography from Background Galaxies: The First Megaparsec-Resolution Large-Scale Structure Map at z>2
• Lyman alpha emitting galaxies at 0.2 < z < 0.35 from GALEX spectroscopy
• Lyman alpha emission in high-redshift galaxies
• Linking Ly-alpha and Low-Ionization Transitions at Low Optical Depth
• Clustering of Lyman alpha emitters at z ~ 4.5
• Initial LOFAR observations of Epoch of Reionization windows: II. Diffuse polarized emission in the ELAIS-N1 field
• Escape fraction of ionizing photons from galaxies at z=0--6
• The cosmic star formation rate evolution from z=5 to z=0 from the VIMOS VLT Deep Survey
• The Polarization of Scattered Lyman Alpha Radiation Around High-Redshift Galaxies
• Spectral Energy Distribution Fitting of HETDEX Pilot Survey Lyman-alpha Emitters in COSMOS and GOODS-N
• On the Diffuse Lyman-alpha Halo Around Lyman-alpha Emitting Galaxies
• The Diversity of Diffuse Ly$\alpha$ Nebulae around Star-Forming Galaxies at High Redshift
• Spatially Resolved Gas Kinematics within a Ly$\alpha$ Nebula: Evidence for Large-scale Rotation
• The reanalysis of spectra of GRB 080913 to estimate the neutral fraction of the IGM at a redshift of 6.7
• First Infrared-based implications for the dust attenuation and star formation of typical Ly$\alpha$ emitters
• Galaxy evolution across the optical emission-line diagnostic diagrams?

Cited by in corpus (2)

• Observations of the Lyman-$\alpha$ Universe
• Near-IR narrow-band imaging with CIRCE at the Gran Telescopio Canarias: Searching for Ly$\alpha$-emitters at $z\sim 9.3$