J/ApJ/950/66 EIGER. I. [OIII]-emitting galaxies at 5.3<z<6.9 (Kashino+, 2023)
EIGER.
I. A large sample of [OIII]-emitting galaxies at 5.3<z<6.9 and direct evidence
for local reionization by galaxies.
Kashino D., Lilly S.J., Matthee J., Eilers A.-C., Mackenzie R.,
Bordoloi R., Simcoe R.A.
<Astrophys. J., 950, 66 (2023)>
=2023ApJ...950...66K 2023ApJ...950...66K
ADC_Keywords: QSOs; Intergalactic medium; Spectra, infrared; Surveys;
Galaxies, IR; Redshifts
Keywords: Reionization ; Intergalactic medium ; Emission line galaxies ;
Circumgalactic medium ; High-redshift galaxies ; Protoclusters ;
Galaxy evolution
Abstract:
We present a first sample of 117 [OIII]λλ4960,5008
-selected star-forming galaxies at 5.33<z<6.93 detected in JWST/NIRCam
3.5µm slitless spectroscopy of a 6.5'x3.4' field centered on the
hyperluminous quasar SDSS J010013.02+280225.8 (SDSSJ0100+2802),
obtained as part of the Emission-line galaxies and Intergalactic Gas
in the Epoch of Reionization (EIGER) survey. Three prominent galaxy
overdensities are observed, one of them at the redshift of the quasar.
Galaxies are found within 200pkpc and 105km/s of four known metal
absorption-line systems. We focus on the role of the galaxies in
ionizing the intergalactic medium (IGM) during the later stages of
cosmic reionization and construct the mean Lyα and Lyβ
transmission as a function of distance from the galaxies. At the
lowest redshifts in our study, 5.3<z<5.7, the IGM transmission rises
monotonically with distance from the galaxies, as seen previously at
lower redshifts. In contrast, at 5.7<z<6.14, the transmission of both
Lyα and Lyβ first increases with distance but then peaks at
a distance of 5cMpc before declining. Finally, in the region
6.15<z<6.26, where the additional ionizing radiation from the quasar
dominates, the monotonic increase in transmission with distance is
reestablished. This result is interpreted to represent evidence that
the transmission of the IGM at z∼5.9 toward J0100+2802 results from
the "local" ionizing radiation of galaxies that dominates over the
much-reduced cosmic background.
Description:
We initiated the survey project Emission-line Galaxies and
Intergalactic Gas in the Epoch of Reionization (EIGER). This is built
around a 116hr JWST program of guaranteed time observation (GTO;
PI: Lilly; PID 1243) using deep wide-field slitless spectroscopy
(WFSS) and broadband direct imaging observations using the Near
InfraRed Camera (NIRCam) on JWST.
This paper is based on the first EIGER quasar field to have been
observed (of six planned). We present an overview of the observational
design of EIGER and our first sample of
[OIII]λλ4960,5008-selected galaxies at 5.3<z<6.9 in this
single field. We focus in this paper on early results from the
cross-correlation analysis between the galaxy sample and the
transmission of the intergalactic medium (IGM). The detailed
characterization of the [OIII]-emitting galaxies is presented in
Paper II (Matthee+ 2023ApJ...950...67M 2023ApJ...950...67M).
The specific observations analyzed can be accessed via
http://doi.org/10.17909/yc3h-jn44
We used ground-based spectroscopic observations of QSO J0100+2802 to
measure the transmission as a function of redshift in the Lyα
and Lyβ forest region and identify intervening absorption
systems. The spectroscopic data used in this paper were obtained with
the X-Shooter spectrograph on the VLT (archival ESO program 096.A-0095),
FIRE on the Magellan Telescope (PI: Simcoe), and HIRES on the Keck
Telescope. See Section 3.
Objects:
-------------------------------------------------------------------------------
RA (ICRS) DE Designation(s) (z)
-------------------------------------------------------------------------------
01 00 13.02 +28 02 25.7 SDSS J010013.02+280225.8 = QSO J0100+2802 (z=6.327)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 55 117 [OIII]-emitter sample
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
V/154 : Sloan Digital Sky Surveys (SDSS), Release 16 (DR16) (Ahumada+, 2020)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
J/MNRAS/435/1198 : z∼6 QSOs CIV doublet absorption systems (D'Odorico+, 2013)
J/ApJ/764/9 : High-z MgII absorption QSOs with FIRE. II. (Matejek+, 2013)
J/ApJS/227/11 : PS1 z>5.6 quasars follow-up (Banados+, 2016)
J/ApJ/863/92 : LAE cand. at z∼5.7 in QSO J0148+0600 field (Becker+, 2018)
J/ApJ/883/163 : OI abs. search in Keck and VLT sp. of 199 QSOs (Becker+, 2019)
J/A+A/642/A150 : Quasars as standard candles. III. (Lusso+, 2020)
J/ApJ/903/24 : Lya emitters and QSOs in COMSOS and EGS fields (Mukae+, 2020)
J/ApJ/905/51 : X-SHOOTER/ALMA QSOs. I. NIR sp. (Schindler+, 2020)
J/ApJ/923/223 : VLT/X-SHOOTER & Keck/ESI spectra of z∼5 QSOs (Zhu+, 2021)
J/ApJ/938/L14 : Early results from GLASS-JWST. II. Abell 2744 (Merlin+, 2022)
J/ApJ/932/76 : Lyβ dark gaps in z≲6 QSOs spectra (Zhu+, 2022)
J/ApJ/941/106 : X-SHOOTER/ALMA QSOs. II. BH masses (Farina+, 2022)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- ID [31/20379] Sequential identifier
(<[KLM2023] NNNNN> in Simbad)
7- 24 F18.15 deg RAdeg [15/15.11] Right Ascension (J2000)
26- 43 F18.15 deg DEdeg [27.98/28.1] Declination (J2000)
45- 53 F9.7 --- z [5.33/6.93] Redshift
55- 55 I1 --- Flag [1/2] Reliability flag: confidence=2 (higher)
or 1 (lower)
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 28-Jul-2025