Spectroscopic detection of CIV in a galaxy at z=7.045: Implications for the ionizing spectra of reionization-era galaxies

Abstract

We present Keck/MOSFIRE observations of UV metal lines in four bright gravitationally-lensed z~6-8 galaxies behind the cluster Abell 1703. The spectrum of A1703-zd6, a highly-magnified star forming galaxy with a Lyman-alpha redshift of z=7.045, reveals a confident detection of the nebular CIV emission line (unresolved with FWHM < 125 km/s). UV metal lines are not detected in the three other galaxies. At z~2-3, nebular CIV emission is observed in just 1% of UV-selected galaxies. The presence of strong CIV emission in one of the small sample of galaxies targeted in this paper may indicate hard ionizing spectra are more common at z~7. The total estimated equivalent width of the CIV doublet (38 A) and CIV/Lyman-alpha flux ratio (0.3) are comparable to measurements of narrow-lined AGNs. Photoionization models show that the nebular CIV line can also be reproduced by a young stellar population, with very hot metal poor stars dominating the photon flux responsible for triply ionizing carbon. Regardless of the origin of the CIV, we show that the ionizing spectrum of A1703-zd6 is different from that of typical galaxies at z~2, producing more H ionizing photons per unit 1500A luminosity and a larger flux density at 30-50 eV. If such extreme radiation fields are typical in UV-selected systems at z>7, it would indicate that reionization-era galaxies are more efficient ionizing agents than previously thought. Alternatively, we suggest that the small sample of Lyman-alpha emitters at z>7 may trace a rare population with intense radiation fields capable of ionizing their surrounding hydrogen distribution. Additional constraints on high ionization emission lines in galaxies with and without Lyman-alpha detections will help clarify whether hard ionizing spectra are common in the reionization era.

arXiv comment11 pages, 6 figures, submitted to MNRAS

References in corpus (74)

• Stellar population synthesis at the resolution of 2003
• Galactic Stellar and Substellar Initial Mass Function
• The Dust Content and Opacity of Actively Star-Forming Galaxies
• A Simple Model for the Absorption of Starlight by Dust in Galaxies
• Rest-Frame Ultraviolet Spectra of z~3 Lyman Break Galaxies
• A simple model to interpret the ultraviolet, optical and infrared emission from galaxies
• UV Luminosity Functions at redshifts z~4 to z~10: 10000 Galaxies from HST Legacy Fields
• The Structure and Kinematics of the Circum-Galactic Medium from Far-UV Spectra of z~2-3 Galaxies
• Cosmic Reionization and Early Star-Forming Galaxies: A Joint Analysis of New Constraints from Planck and Hubble Space Telescope
• PARSEC evolutionary tracks of massive stars up to $350M_{\odot }$ at metallicities 0.0001$\le Z\le$0.04
• Strong Nebular Line Ratios in the Spectra of z~2-3 Star-forming Galaxies: First Results from KBSS-MOSFIRE
• New Constraints on Cosmic Reionization from the 2012 Hubble Ultra Deep Field Campaign
• The Abundance of Star-Forming Galaxies in the Redshift Range 8.5 to 12: New Results from the 2012 Hubble Ultra Deep Field Campaign
• Nebular Emission from Star-Forming Galaxies
• Keck Spectroscopy of 3<z<7 Faint Lyman Break Galaxies: The Importance of Nebular Emission in Understanding the Specific Star Formation Rate and Stellar Mass Density
• The 2013 Release of Cloudy
• UV-Continuum Slopes of >4000 z~4-8 Galaxies from the HUDF/XDF, HUDF09, ERS, CANDELS-South, and CANDELS-North Fields
• A new multi-field determination of the galaxy luminosity function at z=7-9 incorporating the 2012 Hubble Ultra Deep Field imaging
• CLASH: Three Strongly Lensed Images of a Candidate z ~ 11 Galaxy
• The Relation Between SFR and Stellar Mass for Galaxies at 3.5 $\le z\le$ 6.5 in CANDELS
• The Most Luminous z~9-10 Galaxy Candidates yet Found: The Luminosity Function, Cosmic Star-Formation Rate, and the First Mass Density Estimate at 500 Myr
• CANDELS: The Evolution of Galaxy Rest-Frame Ultraviolet Colors from z = 8 to 4
• A highly magnified candidate for a young galaxy seen when the Universe was 500 Myrs old
• Physical Conditions in a Young, Unreddened, Low Metallicity Galaxy at High Redshift
• The mass evolution of the first galaxies: stellar mass functions and star formation rates at $4<z<7$ in the CANDELS GOODS-South field
• The galaxy stellar mass function at 3.5<z<7.5 in the CANDELS/UDS, GOODS-South, and HUDF fields
• Evidence for Ubiquitous, High-EW Nebular Emission in z~7 Galaxies: Towards a Clean Measurement of the Specific Star Formation Rate using a Sample of Bright, Magnified Galaxies
• The Spectral Energy Distributions Of z~8 Galaxies From The IRAC Ultra Deep Fields: Emission Lines, Stellar Masses, And Specific Star Formation Rates At 650 Myr
• Keck Spectroscopy of Faint 3<z<8 Lyman Break Galaxies:- Evidence for a Declining Fraction of Emission Line Sources In the Redshift Range 6<z<8
• Line Emitting Galaxies Beyond a Redshift of 7: An Improved Method for Estimating the Evolving Neutrality of the Intergalactic Medium
• The Cosmic BPT Diagram: Confronting Theory with Observations
• Keck Spectroscopy of Faint 3<z<7 Lyman Break Galaxies:- II. A High Fraction of Line Emitters at Redshift Six
• The UV Luminosity Function of star-forming galaxies via dropout selection at redshifts z ~ 7 and 8 from the 2012 Ultra Deep Field campaign
• Structure and Morphologies of z~7-8 Galaxies from ultra-deep WFC3/IR Imaging of the HUDF
• Ultraviolet Emission Lines in Young Low Mass Galaxies at z~2: Physical Properties and Implications for Studies at z>7
• Very Strong Emission-Line Galaxies in the WISP Survey and Implications for High-Redshift Galaxies
• 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
• The changing Lya optical depth in the range 6<z<9 from MOSFIRE spectroscopy of Y-dropouts
• Rapid Decline of Lyman-alpha Emission Toward the Reionization Era
• Rest-Frame Optical Spectra of Three Strongly Lensed Galaxies at z~2
• High-precision Photometric Redshifts from Spitzer/IRAC: Extreme [3.6]-[4.5] Colors Identify Galaxies in the Redshift Range z~6.6-6.9
• The Evolution of C/O in Dwarf Galaxies from HST Fos Observations
• 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
• Extreme Emission Line Galaxies in CANDELS: Broad-Band Selected, Star-Bursting Dwarf Galaxies at z>1
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• The Population of Faint Optically-Selected AGN at z~3
• A Geometrically Supported $z\sim 10$ Candidate Multiply-Imaged by the Hubble Frontier Fields Cluster Abell 2744
• Evolution of the Sizes of Galaxies over 7<z<12 Revealed by the 2012 Hubble Ultra Deep Field Campaign
• The UV Properties of Star Forming Galaxies I: HST WFC3 Observations of Very-high Redshift Galaxies
• The Star Formation Rate Function for Redshift z~4-7 Galaxies: Evidence for a Uniform Build-Up of Star-Forming Galaxies During the First 3 Gyr of Cosmic Time
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• A remarkably high fraction of strong Ly_alpha emitters amongst luminous redshift 6.0<z<6.5 Lyman break galaxies in the UKIDSS Ultra-Deep Survey
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• The Nature of Extreme Emission Line Galaxies at z=1-2: Kinematics and Metallicities from Near-Infrared Spectroscopy
• Gas Motion Study of Lya Emitters at z~2 Using UV and Optical Spectral Lines
• CLASH: A Census of Magnified Star-Forming Galaxies at z ~ 6-8
• Slow Evolution of the Specific Star Formation Rate at z>2: The Impact of Dust, Emission Lines, and A Rising Star Formation History
• On the rapid demise of Lyman-alpha emitters at z>7 due to the increasing incidence of optically thick absorption systems
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• Candidate Type II Quasars at 2 < z < 4.3 in the Sloan Digital Sky Survey III
• The Physical Conditions, Metallicity and Metal Abundance Ratios In a Highly Magnified Galaxy at z = 3.6252
• The Low Mass End of the Fundamental Relation for Gravitationally Lensed Star Forming Galaxies at 1<z<6
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• Lyman alpha emission in high-redshift galaxies
• Testing metallicity indicators at z~1.4 with the gravitationally lensed galaxy CASSOWARY 20
• Contamination of Broad-Band Photometry by Nebular Emission in High Redshift Galaxies: Investigations with Keck's MOSFIRE Near-Infrared Spectrograph
• High Carbon in I Zwicky 18: New Results from Hubble Space Telescope Spectroscopy
• The unusual NIV]-emitter galaxy GDS J033218.92-275302.7: star formation or AGN-driven winds from a massive galaxy at z=5.56
• Keck spectroscopic survey of strongly lensed galaxies in Abell 1703: further evidence for a relaxed, unimodal cluster
• The unbiased measurement of UV spectral slopes in low luminosity galaxies at z=7
• Bright Strongly Lensed Galaxies at Redshift z~ 6-7 behind the Clusters Abell 1703 and CL0024+161
• Through the Looking Glass: Bright, Highly Magnified Galaxy Candidates at z~7 Behind Abell 1703

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• Emission Line Galaxies in the SHARDS Hubble Frontier Fields II: Limits on Lyman-Continuum Escape Fractions of Lensed Emission Line Galaxies at Redshifts 2 < z < 3.5
• JADES Dark Horse: demonstrating high-multiplex observations with JWST/NIRSpec dense-shutter spectroscopy in the JADES Origins Field
• The significant contribution of supersoft X-ray Sources to the nebular HeII line emission
• Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs). XIV. A Candidate Type-II Quasar at z=6.1292
• Catastrophic Cooling in Superwinds. II. Exploring the Parameter Space
• REBELS-IFU: Spatially Resolved Ionizing Photon Production Efficiencies of 12 Bright Galaxies in the Epoch of Reionization
• New simulation of QSO X-ray heating during the Cosmic Dawn