Illuminating the Dark Side of Cosmic Star Formation. III. Building the Largest Homogeneous Sample of Radio-selected Dusty Star-forming Galaxies in COSMOS with PhoEBO

Scientific paper - Original scientific paper

• Author: Fabrizio Gentile
• Author: Margherita Talia
• Author: Meriem Behiri
• Author: Giovanni Zamorani
• Author: Luigi Barchiesi
• Author: Cristian Vignali
• Author: Francesca Pozzi
• Author: Matthieu Bethermin
• Author: Andrea Enia
• Author: Andreas L. Faisst
• Author: Marika Giulietti
• Author: Carlotta Gruppioni
• Author: Andrea Lapi
• Author: Marcella Massardi
• Author: Vernesa Smolčić
• Author: Mattia Vaccari
• Author: Andrea Cimatti
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

In the last decades, an increasing scientific interest has been growing in the elusive population of dark (i.e., lacking an optical/near-IR, hereafter NIR, counterpart) dusty star-forming galaxies (DSFGs). Although extremely promising for their likely contribution to the cosmic star formation rate density (SFRD) and for their possible role in the evolution of the first massive and passive galaxies around z ∼ 3, the difficulty in selecting statistically significant samples of dark DSFGs is limiting their scientific potentialities. This work presents the first panchromatic study of a sample of 263 radio-selected NIR-dark (RS-NIRdark) galaxies discovered in the COSMOS field following the procedure by Talia et al. These sources are selected as radio-bright galaxies (S 3 GHz > 12.65 μJy) with no counterpart in the NIR-selected COSMOS2020 catalog (Ks ≳ 25.5 mag). For these sources, we build a new photometric catalog including accurate photometry from the optical to the radio obtained with a new deblending pipeline (Photometry Extractor for Blended Objects, or PHOEBO). We employ this catalog to estimate the photo-zs and the physical properties of the galaxies through an spectral energy distribution-fitting procedure performed with two different codes (MAGPHYS and CIGALE). Finally, we estimate the active galactic nucleus contamination in our sample by performing a series of complementary tests. The high values of the median extinction (A v ∼ 4) and star formation rate (SFR ∼ 500 M ⊙ yr‑1) confirm the likely DSFG nature of the RS-NIRdark galaxies. The median photo-z (z ∼ 3) and the presence of a significant tail of high-z candidates (z > 4.5) suggest that these sources are important contributors to the cosmic SFRD and the evolutionary path of galaxies at high redshifts.

• Keywords (english): Extragalactic radio sources; Galaxy evolution; Galaxy formation; High-redshift galaxies; Star formation; 508; 594; 595; 734; 1569; Astrophysics - Astrophysics of Galaxies
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: The Astrophysical Journal
• Numbering: vol. 962, 26
• p-ISSN: 0004-637X
• e-ISSN: 1538-4357
• DOI: https://doi.org/10.3847/1538-4357/ad1519
• URN:NBN: urn:nbn:hr:217:425331
• Publication: 2024-02-02
• Document URL: https://iopscience.iop.org/article/10.3847/1538-4357/ad1519
• Type of resource: Text
• Access conditions: Open access
• Public note: © 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.. Received 2023 March 27; revised 2023 December 4; accepted 2023 December 7; published 2024 February 2.
• Created on: 2024-06-10 12:37:50