Spectroscopy of z ~ 7 candidate galaxies: Using Lyman-alpha to constrain the neutral fraction of hydrogen in the high-redshift universe

Abstract

Following our previous spectroscopic observations of $z>7$ galaxies with Gemini/GNIRS and VLT/XSHOOTER, which targeted a total of 8 objects, we present here our results from a deeper and larger VLT/FORS2 spectroscopic sample of Wide Field Camera 3 selected $z>7$ candidate galaxies. With our FORS2 setup we cover the 737-1070nm wavelength range, enabling a search for Lyman-$\alpha$ in the redshift range spanning 5.06 - 7.80. We target 22 $z$-band dropouts and find no evidence of Lyman-$\alpha$ emission, with the exception of a tentative detection ($<5\sigma$, which is our adopted criterion for a secure detection) for one object. The upper limits on Lyman-$\alpha$ flux and the broad-band magnitudes are used to constrain the rest-frame Equivalent Widths for this line emission. We analyse our FORS2 observations in combination with our previous GNIRS and XSHOOTER observations, and suggest that a simple model where the fraction of high rest-frame Equivalent Width emitters follows the trend seen at $z=3-6.5$ is inconsistent with our non-detections at $z\sim 7.8$ at the 96\% confidence level. This may indicate that a significant neutral HI fraction in the intergalactic medium suppresses Lyman-$\alpha$, with an estimated neutral fraction ${\chi }_{HI}\sim 0.5$, in agreement with other estimates.

accepted for publication in MNRAS

References in corpus (10)

• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Likelihoods and Parameters from the WMAP data
• A luminous quasar at a redshift of z = 7.085
• Studying Reionization with Ly-alpha Emitters
• Can the intergalactic medium cause a rapid drop in Lyman alpha emission at z>6?
• Rapid Decline of Lyman-alpha Emission Toward the Reionization Era
• Lyman-alpha Emitters During the Early Stages of Reionization
• Evolution in the Escape Fraction of Ionizing Photons and the Decline in Strong Lya Emission from z>6 Galaxies
• The GLARE Survey II. Faint z=6 Ly-alpha Line Emitters in the HUDF
• Signatures of reionization on Lyman alpha emitters
• Spectroscopic observation of Ly$\alpha$ emitters at z~7.7 and implications on re-ionization

Cited by in corpus (115)

• The trouble with $H_0$
• Reionization after Planck: The Derived Growth of the Cosmic Ionizing Emissivity now matches the Growth of the Galaxy UV Luminosity Density
• JADES NIRSpec Spectroscopy of GN-z11: Lyman-$\alpha$ emission and possible enhanced nitrogen abundance in a $z=10.60$ luminous galaxy
• Stellar Population Effects on the Inferred Photon Density at Reionization
• The Universe is Reionizing at z~7: Bayesian Inference of the IGM Neutral Fraction Using Ly$\alpha$ Emission from Galaxies
• Conditions for Reionizing the Universe with A Low Galaxy Ionizing Photon Escape Fraction
• Evidence for PopIII-like stellar populations in the most luminous Lyman-$\alpha$ emitters at the epoch of re-ionisation: spectroscopic confirmation
• New observations of z~7 galaxies: evidence for a patchy reionization
• 21CMMC: an MCMC analysis tool enabling astrophysical parameter studies of the cosmic 21 cm signal
• Inferences on the Timeline of Reionization at z~8 From the KMOS Lens-Amplified Spectroscopic Survey
• A Spectroscopic Redshift Measurement for a Luminous Lyman Break Galaxy at z=7.730 using Keck/MOSFIRE
• 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
• The THESEUS space mission concept: science case, design and expected performances
• First Results from HERA Phase I: Upper Limits on the Epoch of Reionization 21 cm Power Spectrum
• Can the intergalactic medium cause a rapid drop in Lyman alpha emission at z>6?
• Spectroscopic detections of CIII]1909 at z~6-7: A new probe of early star forming galaxies and cosmic reionisation
• Feedback-regulated star formation and escape of LyC photons from mini-haloes during reionisation
• High-precision Photometric Redshifts from Spitzer/IRAC: Extreme [3.6]-[4.5] Colors Identify Galaxies in the Redshift Range z~6.6-6.9
• Identification of the brightest Lyα emitters at z=6.6: implications for the evolution of the luminosity function in the re-ionisation era
• MMT/MMIRS spectroscopy of $z=1.3-2.4$ extreme [OIII] emitters: Implications for galaxies in the reionization-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
• HERA Phase I Limits on the Cosmic 21-cm Signal: Constraints on Astrophysics and Cosmology During the Epoch of Reionization
• The LyA-LyC Connection: Evidence for an Enhanced Contribution of UV-faint Galaxies to Cosmic Reionization
• Revealing reionization with the thermal history of the intergalactic medium: new constraints from the Lyman-$\alpha$ flux power spectrum
• The VIMOS Ultra-Deep Survey (VUDS): fast increase of the fraction of strong Lyman alpha emitters from z=2 to z=6
• Lyman-alpha emitters gone missing: evidence for late reionization?
• Astraeus I: The interplay between galaxy formation and reionization
• CANDELSz7: a large spectroscopic survey of CANDELS galaxies in the reionization epoch
• Cosmic Reionization On Computers II. Reionization History and Its Back Reaction on Early Galaxies
• The Global History of Reionisation
• The Lyman-alpha luminosity function at z=5.7-6.6 and the steep drop of the faint end: implications for reionization
• ALMA [CII] detection of a redshift 7 lensed galaxy behind RXJ1347.1-1145
• Constraints on deviations from $\Lambda$CDM within Horndeski gravity
• MMT Spectroscopy of Lyman-alpha at z$\simeq$7: Evidence for Accelerated Reionization Around Massive Galaxies
• A VLT/FORS2 view at $z\sim 6$: Lyman-$\alpha$ emitter fraction and galaxy physical properties at the edge of the epoch of cosmic reionization
• Evolution in the Escape Fraction of Ionizing Photons and the Decline in Strong Lya Emission from z>6 Galaxies
• Spectroscopic Constraints on UV Metal Line Emission at z~6-9: The Nature of Lyman-alpha Emitting Galaxies in the Reionization-Era
• 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 $L^{\ast }$
• Cosmological Constraints on Interacting Light Particles
• Heating of the Intergalactic Medium by Hydrogen Reionization
• Inferring the IGM Neutral Fraction at z ~ 6-8 with Low-Luminosity Lyman Break Galaxies
• First Light And Reionisation Epoch Simulations (FLARES) V: The redshift frontier
• The Grism Lens-Amplified Survey from Space (GLASS). III. A census of Lyα Emission at $z\gtrsim$7 from HST Spectroscopy
• Confirmation of a Steep Luminosity Function for Lyman-alpha Emitters at z = 5.7: A Major Component of Reionization
• Strong Ly$\alpha$ Emission in an Overdense Region at $z=6.8$: A Very Large ($R\sim 3$ physical Mpc) Ionized Bubble in COSMOS?
• The imprint of cosmic reionisation on the luminosity function of galaxies
• CHORUS II. Subaru/HSC Determination of the Ly$\alpha$ Luminosity Function at $z=7.0$: Constraints on Cosmic Reionization Model Parameter
• Hydrogen Reionization in the Illustris universe
• The Grism Lens-Amplified Survey from Space (GLASS). XI. Detection of CIV in Multiple Images of $z=6.11$ Ly$\alpha$ Emitter Behind RXCJ2248.7-4431
• MIDIS: Strong (Hb + [OIII]) and Ha emitters at redshift $z\simeq 7-8$ unveiled with JWST/NIRCam and MIRI imaging in the Hubble eXtreme Deep Field (XDF)
• Introducing SPHINX-MHD: The Impact of Primordial Magnetic Fields on the First Galaxies, Reionization, and the Global 21cm Signal
• A New Constraint on the Ly$\alpha$ Fraction of UV Very Bright Galaxies at Redshift 7
• Large Scale Environment of a $z=6.61$ Luminous Quasar Probed by Ly$\alpha$ Emitters and Lyman Break Galaxies
• The impact of an evolving stellar initial mass function on early galaxies and reionisation
• Spectroscopic observation of Ly$\alpha$ emitters at z~7.7 and implications on re-ionization
• A fresh look into the interacting dark matter scenario
• The ALMA REBELS Survey: Efficient Ly$\alpha$ Transmission of UV-Bright z$\simeq$7 Galaxies from Large Velocity Offsets and Broad Line Widths
• Lyman-alpha spectroscopy of extreme [OIII] emitting galaxies at $z\simeq 2-3$: Implications for Ly$\alpha$ visibility and LyC leakage at $z>6$
• Peering into cosmic reionization: the Ly$\alpha$ visibility evolution from galaxies at $z$ = 4.5-8.5 with JWST
• Lyman-Alpha Emitting Galaxies as a Probe of Reionization: Large-Scale Bubble Morphology and Small-Scale Absorbers
• Constraining Reionization with the $z\sim 5-6$ Lyman-$\alpha$ Forest Power Spectrum: the Outlook after Planck
• Frontier Fields : Combining HST, VLT and Spitzer data to explore the $z$$\sim$8 Universe behind the lensing cluster MACS0416$-$2403
• A 10 deg${}^2$ Lyman-$\alpha$ survey at z=8.8 with spectroscopic follow-up: strong constraints on the LF and implications for other surveys
• The ALPINE-ALMA [CII] survey: Small Lya-[CII] velocity offsets in main-sequence galaxies at 4.4 < z < 6
• Spectroscopically Confirmed Lyman-Alpha Emitters from Redshift 5 to 7 Behind Ten Galaxy Cluster Lenses
• The MUSE-Wide survey: A measurement of the Ly$\alpha$ emitting fraction among $z>3$ galaxies
• Equivalent widths of Lyman $\alpha$ emitters in MUSE-Wide and MUSE-Deep
• Warm dark matter and the ionization history of the Universe
• Connecting Faint End Slopes of the Lyman-$\alpha$ emitter and Lyman-break Galaxy Luminosity Functions
• Nebular Line Emission During the Epoch of Reionization
• Observational constraints on key-parameters of cosmic reionisation history
• Lyα emission from galaxies in the Epoch of Reionization
• MUSE integral-field spectroscopy towards the Frontier Fields cluster Abell S1063: II. Properties of low luminosity Lyman alpha emitters at z>3
• Cross-correlation of the cosmic 21-cm signal and Lyman Alpha Emitters during reionization
• Lyman Alpha Reference Sample: X. Predicting Lyman alpha output from starforming galaxies using multivariate regression
• On the decreasing fraction of Strong Ly$\alpha$ Emitters around $z$ $\sim$ $6$-$7$
• The Super Eight Galaxies: Properties of a Sample of Very Bright Galaxies at $7<z<8$
• Dark-ages Reionization and Galaxy Formation Simulation XX. The Ly$\alpha$ IGM transmission properties and environment of bright galaxies during the Epoch of Reionization
• Nebular line emission from z > 7 galaxies in cosmological simulations: rest-frame UV to Optical lines
• Texas Spectroscopic Search for Ly$\alpha$ Emission at the End of Reionization I. Constraining the Ly$\alpha$ Equivalent Width Distribution at 6.0 < $z$ < 7.0
• Spectroscopy with the JWST Advanced Deep Extragalactic Survey (JADES) -- the NIRSpec/NIRCam GTO galaxy evolution project
• Lyman Alpha and MgII as Probes of Galaxies and their Environments
• Deep rest-frame far-UV spectroscopy of the giant Lyman-alpha emitter 'Himiko'
• A Census of the LyC Photons that Form the UV Background During Reionization
• A 52 hours VLT/FORS2 spectrum of a bright z~7 HUDF galaxy: no Ly-alpha emission
• Texas Spectroscopic Search for Ly$\alpha$ Emission at the End of Reionization II. The Deepest Near-Infrared Spectroscopic Observation at $z\gtrsim 7$
• Clustering and lifetime of Lyman Alpha Emitters in the Epoch of Reionization
• CIII] Emission in Star-forming Galaxies at z ~ 1
• CLEAR: Boosted Ly$\alpha$ Transmission of the Intergalactic Medium in UV bright Galaxies
• Simulating JWST/NIRCam Color Selection of High-Redshift Galaxies
• The Size and Pervasiveness of Ly$\alpha$-UV Spatial Offsets in Star-Forming Galaxies at $z\sim 6$
• The Transient High-Energy Sky and Early Universe Surveyor (THESEUS)
• Constraining Reionization in Progress at z=5.7 with Lyman-$\alpha$ Emitters: Voids, Peaks, and Cosmic Variance
• Joining bits and pieces of reionization history
• Astraeus VIII: A new framework for Lyman-$\alpha$ emitters applied to different reionisation scenarios
• Constraining C iii] Emission in a Sample of Five Luminous z = 5.7 Galaxies
• Finding bright $z\ge 6.6$ Lyman-$\alpha$ emitters with lensing: prospects for Euclid
• Modeling Reionization in a Bursty Universe
• Constraining Very High Mass Population III Stars through He II Emission in Galaxy BDF-521 at z = 7.01
• Star Formation Rate and Extinction in Faint z~4 Lyman-Break Galaxies
• Evolution of the Lyman-α emitting fraction and UV properties of lensed star-forming galaxies between 2.9 < z < 6.7
• Constraining the reionization history with CMB and spectroscopic observations
• Can galaxy evolution mimic cosmic reionization?
• Applications of Stellar Population Synthesis in the Distant Universe
• Dark Twilight Joined with the Light of Dawn to Unveil the Reionization History
• Reconstruction of Reionization History through Dispersion Measure of Fast Radio Bursts
• Lyman alpha Properties of Simulated Galaxies in Overdense Regions: Effects of Galactic Winds at z > 6
• Observing the Epoch of Reionization with the Cosmic Microwave Background
• Signature of the interaction between dark sectors in the reionization process
• What can distant galaxies teach us about massive stars?
• Impact of the turnover in the high-z galaxy luminosity function on the 21-cm signal during Cosmic Dawn and Epoch of Reionization
• Constraint on Matter Power Spectrum on $10^6-10^9{M}_{\odot }$ Scales from ${\tau }_e$
• The MUSE Hubble Ultra Deep Field Survey XIV. The evolution of the Lya emitter fraction from z=3 to z=6
• Exploration of the high-redshift universe enabled by THESEUS