J/ApJ/963/9 JWST size analyis of high-redshift galaxies (Morishita+, 2024)
Enhanced subkiloparsec-scale star formation: results from a JWST size analysis
of 341 galaxies at 5<z<14.
Morishita T., Stiavelli M., Chary R.-R., Trenti M., Bergamini P.,
Chiaberge M., Leethochawalit N., Roberts-Borsani G., Shen X., Treu T.
<Astrophys. J., 963, 9 (2024)>
=2024ApJ...963....9M 2024ApJ...963....9M
ADC_Keywords: Galaxies, photometry; Redshifts; Infrared sources; Optical;
Galaxies, radius; Magnitudes, absolute; Ultraviolet
Keywords: Galaxy structure ; High-redshift galaxies ; Star formation
Abstract:
We present a comprehensive search and analysis of high-redshift
galaxies in a suite of nine public JWST extragalactic fields taken in
Cycle 1, covering a total effective search area of ∼358arcmin2.
Through conservative (8σ) photometric selection, we identify
341 galaxies at 5<z<14, with 109 having spectroscopic redshift
measurements from the literature, including recent JWST NIRSpec
observations. Our regression analysis reveals that the rest-frame UV
size-stellar mass relation follows Reff∝M*0.19±0.03,
similar to that of star-forming galaxies at z∼3, but scaled down in
size by ∼0.7dex. We find a much slower rate for the average size
evolution over the redshift range, Reff∝(1+z)-0.4±0.2,
than that derived in the literature. A fraction (∼13%) of our sample
galaxies are marginally resolved even in the NIRCam imaging (≲100pc),
located at ≳1.5σ below the derived size-mass slope. These
compact sources exhibit a high star formation surface density
ΣSFR>10M☉/yr/kpc2, a range in which only <0.01% of the
local star-forming galaxy sample is found. For those with available
NIRSpec data, no evidence of ongoing supermassive black hole accretion
is observed. A potential explanation for the observed high
[OIII]-to-Hβ ratios could be high shock velocities, likely
originating within intense star-forming regions characterized by high
ΣSFR. Lastly, we find that the rest-frame UV and optical sizes
of our sample are comparable. Our results are consistent with these
early galaxies building up their structures inside out and being yet
to exhibit the strong color gradient seen at lower redshift.
Description:
We base our analysis on nine public deep fields from JWST Cycle 1. For
all fields, except for the GLASS/Ultradeep NIRSpec and NIRCam
ObserVations before the Epoch of Reionization (UNCOVER) and JWST
Advanced Deep Extragalactic Survey (JADES)-GOODS (GDS) fields, where
the final mosaic images are made publicly available by the teams, we
retrieve the raw-level images from the MAST archive and reduce those
with the official JWST pipeline, with several customized steps as
detailed in the paper.
To ensure our selection of high-redshift sources is as consistent as
possible, we consider fields that have images in at least six filters
(F115W, F150W, F200W, F277W, F356W, and F444W). Some fields have
additional blue filters (F070W and F090W) and several medium bands
(F300M, F335M, F410M, F430M, and F480M), which extend the search range
toward lower redshift and improve photometric redshift estimates. When
spectroscopic redshift measurements are available (from either ground
or recent JWST observations), we include and use them for photometric
flux calibration (Section 3.1), as well as for sample selection
(spec-z supersede dropout or photo-z).
The PAR1199 field (11:49:47.31,+22:29:32.1) was taken as part of a
Cycle 1 Guaranteed Time Observations (GTO) program (PID 1199;
Stiavelli+ 2023ApJ...957L..18S 2023ApJ...957L..18S) in 2023 May and June.
See Section 2.2.1.
The J1235 field (12:35:54.4631,+04:56:8.50) is one of the
low-ecliptic-latitude fields that were observed as part of a
commissioning program used for NIRCam flat field (PID 1063;
PI: Sunnquist). Two separate visits were made in 2022 March-April
and May. See Section 2.2.2.
The NIRCam imaging in the North Ecliptic Pole Time-domain field
(17:22:47.896,+65:49:21.54) was taken as part of a GTO program
(PID 2738; Windhorst+ 2023AJ....165...13W 2023AJ....165...13W). See Section 2.2.3.
Two large NIRCam mosaics are scheduled in a Cycle 1 General Observer
program, PRIMER (PID 1837; PI: Dunlop). PRIMER observed two
extragalactic fields, the CANDELS UKIDSS Ultra-Deep Survey (UDS) and
COSMOS fields. In this study, we use the data taken during the first
visit in both fields. See Section 2.2.4.
The Next Generation Deep Extragalactic Exploratory Public (NGDEEP)
survey (PID 2079; PI: Finkelstein; Bagley+ 2024ApJ...965L...6B 2024ApJ...965L...6B) is a
deep spectroscopic+imaging program using the NIRISS WFSS as the
primary mode and the NIRCam imaging attached as coordinated parallel
in the HUDF-Par2 field. In this study, we use the epoch 1 NIRCam
imaging data. See Section 2.2.5.
The CEERS Survey (Bagley+ 2023ApJ...946L..12B 2023ApJ...946L..12B;
Finkelstein+ 2023ApJ...946L..13F 2023ApJ...946L..13F) is an Early Release Science program
(PID 1345; PI: Finkelstein). The CEERS observations had two separate
visits, one in 2022 June (for four subregions: #1, 2, 3, and 6) and
the other in 2022 December (#4, 5, 7, 8, 9, and 10). We reduce the
NIRCam images separately in each subfield. See Section 2.2.6.
Multiple Cycle 1 programs observed the A2744 field
(00:14:21,-30:24:03), including the GLASS-JWST Early Release Science
Program (PID 1324; Treu+ 2022ApJ...935..110T 2022ApJ...935..110T), the Treasury Survey
program the Ultradeep NIRSpec and NIRCam ObserVations before the Epoch
of Reionization (UNCOVER; PID 2561; Bezanson+ 2024ApJ...974...92B 2024ApJ...974...92B),
and a JWST Director's Discretionary Time program (PID 2756;
PI: W. Chen; Roberts-Borsani+ 2023Natur.618..480R 2023Natur.618..480R). In this study, we
utilize the public imaging data made available by the GLASS-JWST team.
See Section 2.2.7.
We include a deep field from JADES. As of the time of writing, NIRCam
imaging data in one of the deep fields in the GOODS-South field
(3:32:39.3,-27:46:59) are publicly available
(Hainline+ 2024ApJ...964...71H 2024ApJ...964...71H; Rieke+ 2023ApJS..269...16R 2023ApJS..269...16R). We
retrieve the fully processed images and spectroscopic catalogs made
available by the team. See Section 2.2.8.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table5.dat 156 341 Physical properties of the final candidates
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See also:
V/159 : JADES NIRCam & NIRSpec phot. & line fluxes (DR1-DR3) (Rieke+, 2023)
J/ApJS/112/315 : Spectroscopic parameters of Seyfert nuclei (Ho+ 1997)
J/ApJS/173/441 : UV-Luminous galaxies discovered by GALEX (Hoopes+, 2007)
J/A+A/500/947 : Spectroscopy and phot. in A2744 and A2537 (Braglia+, 2009)
J/MNRAS/398/1129 : Central galaxies in groups and clusters (Guo+, 2009)
J/ApJ/728/27 : Chandra & AAOmega observations of Abell 2744 (Owers+, 2011)
J/ApJS/196/11 : Bulge+disk decompositions of SDSS galaxies (Simard+, 2011)
J/MNRAS/427/1666 : Massive galaxies in CANDELS-UDS field (Bruce+, 2012)
J/ApJ/749/121 : Surface brightness profiles if z=2 galaxies (Szomoru+, 2012)
J/ApJS/203/24 : Structural param. of gal. in CANDELS (van der Wel+, 2012)
J/ApJ/765/26 : Very low-z SDSS gal. with Hα emission (Shim+, 2013)
J/ApJS/214/24 : 3D-HST+CANDELS catalog (Skelton+, 2014)
J/ApJS/219/15 : Morphologies of z=0-10 galaxies with HST (Shibuya+, 2015)
J/ApJS/225/27 : 3D-HST Survey: grism spectra master cat. (Momcheva+, 2016)
J/ApJ/835/254 : GLASS. IX. Structural param. from HFF (Morishita+, 2017)
J/ApJ/858/77 : DEIMOS 10K sp. survey in COSMOS field (Hasinger+, 2018)
J/ApJ/855/4 : Lyman break galaxies at z∼6-9 from HFF (Kawamata+, 2018)
J/ApJS/235/36 : SPLASH-SXDF multi-wavelength photometric cat. (Mehta+, 2018)
J/ApJS/253/4 : SuperBoRG: HST parallel imaging data (Morishita, 2021)
J/A+A/646/A83 : 12 massive lensing clusters MUSE obs. (Richard+, 2021)
J/MNRAS/501/1028 : Galaxies at z=1-3 lensed by six HFF clusters (Yang+, 2021)
J/ApJ/927/81 : HFF cluster observations of z∼4-8 galaxies (Bouwens+, 2022)
J/ApJ/952/84 : GLASS-JWST ERSP. III. A2744 (Bergamini+, 2023)
J/A+A/670/A60 : Abell 2744 members (Bergamini+, 2023)
J/ApJ/946/L35 : High-z galaxies from JWST ERO (Morishita+, 2023)
J/ApJS/269/33 : JWST z=4-10 galaxies mass-metallicities (Nakajima+, 2023)
J/ApJ/952/20 : GLASS-JWST ERS Prog. II. ACO 2744 (Paris+, 2023)
Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Subset Dropout subset
15- 23 A9 --- Field Field (1)
25- 30 I6 --- ID [200/146539] ID within Field (1)
32- 42 F11.7 deg RAdeg [3.4/260.8] Right Ascension (J2000)
44- 54 F11.7 deg DEdeg [-30.5/66] Declination (J2000)
56- 59 F4.1 mag UVmag [25.2/30.2] Apparent UV magnitude
61- 65 F5.2 --- z [5/13.8] Redshift (2)
67- 69 F3.1 --- e_z [0.1/1.4]? Lower uncertainty in z (2)
71- 73 F3.1 --- E_z [0.1/2.5]? Upper uncertainty in z (2)
75- 79 F5.1 mag UVMag [-22.9/-16.5] Absolute UV magnitude
81- 83 F3.1 mag e_UVMag [0.1/0.4] Lower uncertainty in UVMag
85- 87 F3.1 mag E_UVMag [0.1/0.3] Upper uncertainty in UVMag
89- 92 F4.1 [Msun] logMs [6.8/10.5] Log of stellar mass
94- 96 F3.1 [Msun] e_logMs [0.1/1.1] Lower uncertainty in logMs
98- 100 F3.1 [Msun] E_logMs [0.1/1.1] Upper uncertainty in logMs
102- 105 F4.1 [Msun/yr] logSFR [-0.4/2] Log of star formation rate
107- 109 F3.1 [Msun/yr] e_logSFR [0.1/0.3] Lower uncertainty in logSFR
111- 113 F3.1 [Msun/yr] E_logSFR [0.1/0.3] Upper uncertainty in logSFR
115- 118 F4.1 --- betaUV [-3/-0.6] Rest-frame UV slope
120- 122 F3.1 --- e_betaUV [0.1/0.4] Lower uncertainty in betaUV
124- 126 F3.1 --- E_betaUV [0.1/0.6] Upper uncertainty in betaUV
128- 132 F5.2 [kpc] logRe [-1.95/0.97] Log of effective major axis
134- 137 F4.2 [kpc] e_logRe [0.01/0.6] Lower uncertainty in logRe
139- 142 F4.2 [kpc] E_logRe [0.01/0.6] Upper uncertainty in logRe
144 A1 --- l_OIIIHb Limit flag on OIIIHb
146- 148 F3.1 [-] OIIIHb [0.1/1.1]? Log, [OIII] to Hβ ratio
150- 152 F3.1 [-] e_OIIIHb [0.1/0.3]? Uncertainty in OIIIHb
154 I1 --- fgal [0/1] 1=flagged in galfit analysis
156 I1 --- fcom [0/1]? 1=classified as compact, Section 4.4
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Note (1): Names are assigned using the following nomenclature:
Field-ID, where Field is given in Tables 1 and 2, is
an optional subgroup, e.g., for CEERS, for processing (see text,
Section 2), and ID is a sequential identifier from the processing.
Most sources do not have corresponding identification in NED.
Note (2): Redshift values with asymmetric errors are photometric redshifts;
spectroscopic redshifts are provided without error.
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History:
From electronic version of the journal
License: CC-BY-4.0
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 20-May-2026