J/ApJ/952/81 JWST PEARLS view of the El Gordo galaxy cluster (Frye+, 2023)
The JWST PEARLS view of the El Gordo galaxy cluster and of the structure it
magnifies.
Frye B.L., Pascale M., Foo N., Leimbach R., Garuda N., Robles P.S.,
Summers J., Diaz C., Kamieneski P., Furtak L.J., Cohen S.H., Diego J.,
Beauchesne B., Windhorst R.A., Willner S.P., Koekemoer A.M., Zitrin A.,
Caminha G., Caputi K.I., Coe D., Conselice C.J., Dai L., Dole H.,
Driver S.P., Grogin N.A., Harrington K., Jansen R.A., Kneib J.-P.,
Lehnert M., Lowenthal J., Marshall M.A., Menanteau F., Pampliega B.A.,
Pirzkal N., Polletta M., Richard J., Robotham A., Ryan R.E.J.,
Rutkowski M.J., Sifon C., Tompkins S., Wang D., Yan H., Yun M.S.
<Astrophys. J., 952, 81 (2023)>
=2023ApJ...952...81F 2023ApJ...952...81F
ADC_Keywords: Clusters, galaxy; Gravitational lensing; Galaxies, IR;
Redshifts
Keywords: Strong gravitational lensing ; Galaxy clusters ;
High-redshift galaxy clusters
Abstract:
The massive galaxy cluster El Gordo (z=0.87) imprints multitudes of
gravitationally lensed arcs onto James Webb Space Telescope
Near-Infrared Camera (NIRCam) images. Eight bands of NIRCam imaging
were obtained in the "Prime Extragalactic Areas for Reionization and
Lensing Science" ("PEARLS") program. Point-spread function-matched
photometry across Hubble Space Telescope and NIRCam filters supplies
new photometric redshifts. A new light-traces-mass lens model based
on 56 image multiplicities identifies the two mass peaks and yields a
mass estimate within 500kpc of (7.0±0.30)x1014M☉. A search
for substructure in the 140 cluster members with spectroscopic
redshifts confirms the two main mass components. The southeastern mass
peak that contains the brightest cluster galaxy is more tightly bound
than the northwestern one. The virial mass within 1.7Mpc is
(5.1±0.60)x1014M☉, lower than the lensing mass. A
significant transverse velocity component could mean the virial mass
is underestimated. We contribute one new member to the previously
known z=4.32 galaxy group. Intrinsic (delensed) positions of the five
secure group members span a physical extent of ∼60kpc. 13 additional
candidates selected by spectroscopic/photometric constraints are small
and faint, with a mean intrinsic luminosity ∼2.2mag fainter than L*.
NIRCam imaging admits a fairly wide range of brightnesses and
morphologies for the group members, suggesting a more diverse galaxy
population in this galaxy overdensity.
Description:
El Gordo is one of seven galaxy clusters selected by the JWST "Prime
Extragalactic Areas for Reionization and Lensing Science" ("PEARLS")
project (Windhorst+ 2023AJ....165...13W 2023AJ....165...13W) on account of its significant
lensing strength and large critical curve perimeter.
NIRCam observations were obtained on 2022 July 29 as a part of the
JWST PEARLS program (PI: Windhorst, Program ID 1176). Exposures were
taken in F090W, F115W, F150W, and F200W in the short-wavelength (SW)
module and in F277W, F356W, F444W, and F410M in the long-wavelength
(LW) module.
We augmented the NIRCam data with bluer HST Wide Field Camera (WFC)
F435W, F606W, and F814W imaging drawn from the literature (PID 14096;
PID 12477).
Three Chandra observations were acquired (ObsIDs 12258, 14022, and
14023; PI: J. Hughes) with a total of 351ks of combined exposure time.
See Section 2.2.
Objects:
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RA (ICRS) DE Designation(s)
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01 02 52.50 -49 14 57.9 El Gordo = ACT-CL J0102-4915
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 95 181 Strong lensing image systems
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See also:
B/hst : HST Archived Exposures Catalog (STScI, 2007)
B/chandra : The Chandra Archive Log (CXC, 1999-2014)
J/AJ/132/926 : Galaxies in the Hubble Ultra Deep Field (Coe+, 2006)
J/ApJ/757/22 : Strong and weak lensing analysis of A2261 (Coe+, 2012)
J/ApJS/206/10 : CANDELS multiwavelength catalog (Galametz+, 2013)
J/ApJ/772/25 : Massive SZE clusters observations with ACT (Sifon+, 2013)
J/ApJ/868/129 : Lensing analysis in Abell 370 (Strait+, 2018)
J/ApJ/884/85 : RELICS: Reionization Lensing Cluster Survey (Coe+, 2019)
J/ApJ/947/20 : Color-selected quiescent gal. at z>3 in JWST (Valentino+, 2023)
J/A+A/678/A3 : ACT-CL J0 102-15 MUSE view (Caminha+, 2023)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- ID Identifier (1)
7- 8 I2 h RAh [1] Hour of Right Ascension (J2000)
10- 11 I2 min RAm [2/3] Minute of Right Ascension (J2000)
13- 18 F6.3 s RAs Second of Right Ascension (J2000)
20- 20 A1 --- DE- [-] Sign of the Declination (J2000)
21- 22 I2 deg DEd [49] Degree of Declination (J2000)
24- 25 I2 arcmin DEm [14/16] Arcminute of Declination (J2000)
27- 31 F5.2 arcsec DEs Arcsecond of Declination (J2000)
33- 33 A1 --- l_F200Wmag Limit flag on F200Wmag
35- 39 F5.2 mag F200Wmag [20.38/29]? JWST/NIRCam apparent F200W AB
band magnitude
41- 46 F6.4 --- zsp [2.18/5.96]? Spectroscopic redshift
48- 48 A1 --- f_zsp Flag on zsp (2)
50- 53 F4.2 --- zph [0.1/6]? Photometric redshift estimate
55- 58 F4.2 --- E_zph [0/4]? Upper uncertainty in zph
60- 63 F4.2 --- e_zph [0/0.4]? Lower uncertainty in zph
65- 65 A1 -- f_zph Flag on zph (2)
67- 71 F5.2 --- zmod [2.2/10.9]? Lens-model predicted redshift
73- 77 F5.1 --- mu [1.1/230]? Magnification factor
79- 88 A10 --- r_OID Reference code for OID (3)
90- 95 A6 --- OID Other designation(s) of the arc
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Note (1): The image system designations for numbers 1-23 follow the
designations of Caminha+ 2023A&A...678A...3C 2023A&A...678A...3C
(table2; <[CGR2023] ACT0102 NNa> in Simbad),
and the image system designations for numbers 24-60 follow
Diego+ 2023A&A...672A...3D 2023A&A...672A...3D
Note (2): Flag as follows:
a = A spectroscopic redshift is measured at this coordinate
in Caminha+ 2023A&A...678A...3C 2023A&A...678A...3C
b = A spectroscopic redshift is assumed along the same arc
and near to this specific coordinate in projection.
c = A spectroscopic redshift is measured not at this coordinate,
but for one or more of its counterimages.
e = A spectroscopic redshift is measured at this coordinate
in Caputi+ 2021ApJ...908..146C 2021ApJ...908..146C
f = A spectroscopic redshift is measured for this arc in this study.
d = The photometric redshift is estimated using EAZY.
Note (3): Reference as follows:
Z13 = Zitrin et al. 2013ApJ...770L..15Z 2013ApJ...770L..15Z
(<[ZMH2013] ACT-CL J0102-4915 cN.Na> or
<[ZMH2013] ACT-CL J0102-4915 N.Na> in Simbad)
Cam22 = Caminha et al. 2023A&A...678A...3C 2023A&A...678A...3C
(<[CGR2023] ACT0102 NNa> in Simbad)
D23 = Diego et al. 2023A&A...672A...3D 2023A&A...672A...3D
D20 = Diego et al. 2020ApJ...904..106D 2020ApJ...904..106D
Ca21 = Caputi et al. 2021ApJ...908..146C 2021ApJ...908..146C
This paper = an additional counterimage discovered in this work.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 01-Sep-2025