Extensive Lensing Survey of Optical and Near-infrared Dark Objects (El Sonido): HST H-faint Galaxies behind 101 Lensing Clusters
Artikel i vetenskaplig tidskrift, 2021

We present a Spitzer/IRAC survey of H-faint (H-160 greater than or similar to 26.4, < 5 sigma) sources in 101 lensing cluster fields. Across a CANDELS/Wide-like survey area of similar to 648 arcmin(2) (effectively similar to 221 arcmin(2) in the source plane), we have securely discovered 53 sources in the IRAC Channel-2 band (CH2, 4.5 mu m; median CH2 = 22.46 +/- 0.11 AB mag) that lack robust HST/WFC3-IR F160W counterparts. The most remarkable source in our sample, namely ES-009 in the field of Abell 2813, is the brightest H-faint galaxy at 4.5 mu m known so far (CH2 = 20.48 +/- 0.03 AB mag). We show that the H-faint sources in our sample are massive (median M-star = 10 10.3 +/- 0.3 M-circle dot, star-forming (median star formation rate =1001 M-circle dot yr(-1)), and dust-obscured (A(v) = 2.6 +/- 0.3) galaxies around a median photometric redshift of z = 3.9 +/- 0.4. The stellar continua of 14 H-faint galaxies can be resolved in the CH2 band, suggesting a median circularized effective radius (R-e,R-circ; lensing corrected) of 1.9 +/- 0.2 kpc and <1.5 kpc for the resolved and whole samples, respectively. This is consistent with the sizes of massive unobscured galaxies at z similar to 4, indicating that H-faint galaxies represent the dusty tail of the distribution of a wider galaxy population. Comparing with the ALMA dust continuum sizes of similar galaxies reported previously, we conclude that the heavy dust obscuration in H-faint galaxies is related to the compactness of both stellar and dust continua (R-e,R-circ similar to 1 kpc). These H-faint galaxies make up 161 3 % of the galaxies in the stellar-mass range of 10(10) - 10(11.2) M-circle dot at z = 3 similar to 5, contributing to 8(-4)(+8)% of the cosmic star formation rate density in this epoch and likely tracing the early phase of massive galaxy formation.


Fengwu Sun

University of Arizona

Eiichi Egami

University of Arizona

Pablo G. Perez-Gonzalez

Centro de Astrobiología (INTA-CSIC)

Ian Smail

Durham University

Karina I. Caputi

Rijksuniversiteit Groningen

Köpenhamns universitet

Franz E. Bauer

Instituto Milenio de Astrofísica

Pontificia Universidad Catolica de Chile

Timothy D. Rawle

Space Telescope Science Institute (STScI)

Seiji Fujimoto

Köpenhamns universitet

Kotaro Kohno

University of Tokyo

Ugne Dudzeviciute

Durham University

Hakim Atek

Sorbonne Université

Matteo Bianconi

University of Birmingham

Scott C. Chapman

Eureka Scientific

Francoise Combes

Collège de France

Sorbonne Université

Mathilde Jauzac

Durham University

University of KwaZulu-Natal

Jean Baptiste Jolly

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik

Anton M. Koekemoer

Space Telescope Science Institute (STScI)

Georgios E. Magdis

Köpenhamns universitet

Danmarks Tekniske Universitet (DTU)

Giulia Rodighiero

Università di Padova

INAF Osservatorio Astrofisico Padova

Wiphu Rujopakarn

Chulalongkorn University

National Astronomical Research Institute of Thailand

University of Tokyo

Daniel Schaerer

Université de Genève

Charles L. Steinhardt

Köpenhamns universitet

Paul Van der Werf

Universiteit Leiden

Gregory L. Walth

Carnegie Observatories

John R. Weaver

Köpenhamns universitet

Astrophysical Journal

0004-637X (ISSN) 1538-4357 (eISSN)

Vol. 922 2 114


Astronomi, astrofysik och kosmologi

Annan geovetenskap och miljövetenskap

Multidisciplinär geovetenskap



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