CANDELSz7: a large spectroscopic survey of CANDELS galaxies in the reionization epoch

Abstract

We present the results of CANDELSz7, an ESO large program aimed at confirming spectroscopically a homogeneous sample of z~6 and z~7 star forming galaxies. The candidates were selected in the GOODS-South, UDS and COSMOS fields using the official CANDELS catalogs based on H160-band detections. Standard color criteria, which were tailored depending on the ancillary multi-wavelength data available for each field, were applied to select more than 160 candidate galaxies at z~6 and z~7. Deep medium resolution FORS2 spectroscopic observations were then conducted with integration times ranging from 12 to 20 hours, to reach a Lyalpha flux limit of approximately 1-3x 10-18 erg/s/cm^2 at 3sigma. For about 40% of the galaxies we could determine a spectroscopic redshift, mainly through the detection of a single emission line that we interpret as Lyalpha emission, or for some of the brightest objects (H160< 25.5) from the presence of faint continuum and sharp drop that we interpret as a Lyman break. In this paper we present the redshifts and main properties of 65 newly confirmed high redshift galaxies. Adding previous proprietary and archival data we assemble a sample of ~260 galaxies that we use to explore the evolution of the Lyalpha fraction in Lyman break galaxies and the change in the shape of the emission line between z~6 and z~7. We also discuss the accuracy of the CANDELS photometric redshifts in this redshift range.

arXiv commentAccepted for publication in Astronomy & Astrophysics

References in corpus (78)

• CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey
• CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey - The Hubble Space Telescope Observations, Imaging Data Products and Mosaics
• 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 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
• Structural Parameters of Galaxies in CANDELS
• CANDELS Multi-wavelength Catalogs: Source Detection and Photometry in the GOODS-South Field
• Model-independent evidence in favor of an end to reionization by z~6
• Keck Spectroscopy of Faint 3<z<7 Lyman Break Galaxies: - I. New constraints on cosmic reionisation from the luminosity and redshift-dependent fraction of Lyman-alpha emission
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• UV-Continuum Slopes of >4000 z~4-8 Galaxies from the HUDF/XDF, HUDF09, ERS, CANDELS-South, and CANDELS-North Fields
• A dusty, normal galaxy in the epoch of reionization
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• Lyman-alpha and CIII] Emission in z=7-9 Galaxies: Accelerated Reionization Around Luminous Star Forming Systems?
• The VIMOS Ultra-Deep Survey: ~10,000 galaxies with spectroscopic redshifts to study galaxy assembly at early epochs 2<z<~6
• Ly-alpha Emission-Line Galaxies at z = 3.1 in the Extended Chandra Deep Field South
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• The Great Observatories Origins Deep Survey. VLT/FORS2 Spectroscopy in the GOODS-South Field: Part III
• CANDELS Multiwavelength catalogs: Source Identification and Photometry in the CANDELS UKIDSS Ultra-Deep Survey Field
• Faint AGNs at z>4 in the CANDELS GOODS-S field: looking for contributors to the reionization of the Universe
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• Ly Alpha Emitters at z=5.7 in the Subaru Deep Field
• 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
• Stellar masses from the CANDELS survey: the GOODS-South and UDS fields
• ALMA Spectroscopic Survey in the Hubble Ultra Deep Field: The Infrared Excess of UV-selected z=2-10 galaxies as a function of UV-continuum Slope and Stellar Mass
• 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
• Keck Spectroscopy of Faint 3<z<7 Lyman Break Galaxies:- II. A High Fraction of Line Emitters at Redshift Six
• Spectroscopic detection of CIV in a galaxy at z=7.045: Implications for the ionizing spectra of reionization-era galaxies
• Planck intermediate results. XLVII. Planck constraints on reionization history
• Rotation in [CII]-emitting gas in two galaxies at a redshift of 6.8
• Can the intergalactic medium cause a rapid drop in Lyman alpha emission at z>6?
• Hubble imaging of the ionizing radiation from a star-forming galaxy at z=3.2 with fesc>50%
• Intergalactic Transmission and its Impact on the Lyα Line
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• The MUSE Hubble Ultra Deep Field Survey: IV. Global properties of C III] emitters
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• Serendipitous Discovery of an Overdensity of Lyman-Alpha Emitters at z~4.8 in the Cl1604 Supercluster Field
• Lyman-Alpha Emitting Galaxies as a Probe of Reionization: Large-Scale Bubble Morphology and Small-Scale Absorbers
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• The MUSE Hubble Ultra Deep Field Survey: III. Testing photometric redshifts to 30th magnitude
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