TY - JOUR
T1 - A Census of the Bright z = 8.5-11 Universe with the Hubble and Spitzer Space Telescopes in the CANDELS Fields
AU - Finkelstein, Steven L.
AU - Bagley, Micaela
AU - Song, Mimi
AU - Larson, Rebecca
AU - Papovich, Casey
AU - Dickinson, Mark
AU - Finkelstein, Keely D.
AU - Koekemoer, Anton M.
AU - Pirzkal, Norbert
AU - Somerville, Rachel S.
AU - Yung, L. Y.Aaron
AU - Behroozi, Peter
AU - Ferguson, Harry
AU - Giavalisco, Mauro
AU - Grogin, Norman
AU - Hathi, Nimish
AU - Hutchison, Taylor A.
AU - Jung, Intae
AU - Kocevski, Dale
AU - Kawinwanichakij, Lalitwadee
AU - Rojas-Ruiz, Sofía
AU - Ryan, Russell
AU - Snyder, Gregory F.
AU - Tacchella, Sandro
N1 - Funding Information:
We acknowledge that the location where most of this work took place, the University of Texas at Austin, sits on indigenous land. The Tonkawa lived in central Texas and the Comanche and Apache moved through this area. We pay our respects to all of the American Indian and Indigenous Peoples and communities who have been or have become a part of these lands and territories in Texas, on this piece of Turtle Island. We thank Adam Kraus, Karl Gebhardt, Stephen Wilkins, Rebecca Bowler, Charlotte Mason, Jim Dunlop, and Gabe Brammer for helpful conversations. We thank the anonymous referee for the detailed and useful comments. S.L.F. and M.B. acknowledge support from NASA through ADAP award 80NSSC18K0954. Support for Hubble Space Telescope programs #15697 and #15862 was provided by NASA through a grant from the Space Telescope Science Institute, which is operated by the Associations of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. S.R.R. acknowledges financial support from the International Max Planck Research School for Astronomy and Cosmic Physics at the University of Heidelberg (IMPRS–HD). This research has benefitted from the SpeX Prism Library (and/or SpeX Prism Library Analysis Toolkit), maintained by Adam Burgasser at http://www.browndwarfs.org/spexprism .
Publisher Copyright:
© 2022. The Author(s). Published by the American Astronomical Society.
PY - 2022/3/1
Y1 - 2022/3/1
N2 - We present the results from a new search for candidate galaxies at z ≈ 8.5-11 discovered over the 850 arcmin2 area probed by the Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS). We use a photometric-redshift selection including both Hubble and Spitzer Space Telescope photometry to robustly identify galaxies in this epoch at H 160 < 26.6. We use a detailed vetting procedure, including screening against persistence and stellar contamination, and the inclusion of ground-based imaging and follow-up Hubble Space Telescope imaging to build a robust sample of 11 candidate galaxies, three presented here for the first time. The inclusion of Spitzer/IRAC photometry in the selection process reduces contamination, and yields more robust redshift estimates than Hubble alone. We constrain the evolution of the rest-frame ultraviolet luminosity function via a new method of calculating the observed number densities without choosing a prior magnitude bin size. We find that the abundance at our brightest probed luminosities (M UV = - 22.3) is consistent with predictions from simulations that assume that galaxies in this epoch have gas depletion times at least as short as those in nearby starburst galaxies. Due to large Poisson and cosmic variance uncertainties, we cannot conclusively rule out either a smooth evolution of the luminosity function continued from z = 4-8, or an accelerated decline at z > 8. We calculate that the presence of seven galaxies in a single field Extended Groth Strip is an outlier at the 2σ significance level, implying the discovery of a significant over-density. These scenarios will be imminently testable to high confidence within the first year of observations of the James Webb Space Telescope.
AB - We present the results from a new search for candidate galaxies at z ≈ 8.5-11 discovered over the 850 arcmin2 area probed by the Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey (CANDELS). We use a photometric-redshift selection including both Hubble and Spitzer Space Telescope photometry to robustly identify galaxies in this epoch at H 160 < 26.6. We use a detailed vetting procedure, including screening against persistence and stellar contamination, and the inclusion of ground-based imaging and follow-up Hubble Space Telescope imaging to build a robust sample of 11 candidate galaxies, three presented here for the first time. The inclusion of Spitzer/IRAC photometry in the selection process reduces contamination, and yields more robust redshift estimates than Hubble alone. We constrain the evolution of the rest-frame ultraviolet luminosity function via a new method of calculating the observed number densities without choosing a prior magnitude bin size. We find that the abundance at our brightest probed luminosities (M UV = - 22.3) is consistent with predictions from simulations that assume that galaxies in this epoch have gas depletion times at least as short as those in nearby starburst galaxies. Due to large Poisson and cosmic variance uncertainties, we cannot conclusively rule out either a smooth evolution of the luminosity function continued from z = 4-8, or an accelerated decline at z > 8. We calculate that the presence of seven galaxies in a single field Extended Groth Strip is an outlier at the 2σ significance level, implying the discovery of a significant over-density. These scenarios will be imminently testable to high confidence within the first year of observations of the James Webb Space Telescope.
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U2 - 10.3847/1538-4357/ac3aed
DO - 10.3847/1538-4357/ac3aed
M3 - Article
AN - SCOPUS:85128149488
VL - 928
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 1
M1 - 52
ER -