ALMA Lensing Cluster Survey: A strongly lensed multiply imaged dusty system at z ≥ 6
Journal article, 2021
We report the discovery of an intrinsically faint, quintuply-imaged, dusty galaxy MACS0600-z6 at a redshift z = 6.07 viewed through the cluster MACSJ0600.1–2008 (z = 0.46). A ≃ 4σ dust detection is seen at 1.2mm as part of the ALMA Lensing Cluster Survey (ALCS), an on-going ALMA Large programme, and the redshift is secured via [C II] 158 μm emission described in a companion paper. In addition, spectroscopic follow-up with GMOS/Gemini-North shows a break in the galaxy’s spectrum, consistent with the Lyman break at that redshift. We use a detailed mass model of the cluster and infer a magnification μ ≳ 30 for the most magnified image of this galaxy, which provides an unprecedented opportunity to probe the physical properties of a sub-luminous galaxy at the end of cosmic reionization. Based on the spectral energy distribution, we infer lensing-corrected stellar and dust masses of 2.9-2.3+115 × 109 and 4.8-3.4+45 × 106 M☉, respectively, a star formation rate of 9.7-6.6+220 M☉ yr−1, an intrinsic size of 0.54-0.14+026 kpc, and a luminosity-weighted age of 200 ± 100 Myr. Strikingly, the dust production rate in this relatively young galaxy appears to be larger than that observed for equivalent, lower redshift sources. We discuss if this implies that early supernovae are more efficient dust producers and the consequences for using dust mass as a probe of earlier star formation.
Galaxies: formation
Galaxies: high-redshift
Galaxies: evolution
Gravitational lensing: strong
Author
N. Laporte
University of Cambridge
A. Zitrin
Ben-Gurion University of the Negev
R. S. Ellis
University College London (UCL)
S. Fujimoto
Cosmic Dawn Center (DAWN)
G. Brammer
Cosmic Dawn Center (DAWN)
J. Richard
Centre national de la recherche scientifique (CNRS)
M. Oguri
Research Center for the Early Universe
University of Tokyo
G. B. Caminha
University of Groningen
K. Kohno
Research Center for the Early Universe
University of Tokyo
Y. Yoshimura
University of Tokyo
Y. Ao
University of Science and Technology of China
Chinese Academy of Sciences
F. E. Bauer
Pontificia Universidad Catolica de Chile
Millennium Institute of Astrophysics
Karina I. Caputi
Cosmic Dawn Center (DAWN)
University of Groningen
E. Egami
University of Arizona
D. Espada
National Astronomical Observatory of Japan
SKA Organisation
The Graduate University for Advanced Studies (SOKENDAI)
J. González-López
Las Campanas Observatory
Diego Portales University
B. Hatsukade
University of Tokyo
Kirsten Kraiberg Knudsen
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
M. M. Lee
Max Planck Society
Georgios E. Magdis
Cosmic Dawn Center (DAWN)
Masami Ouchi
University of Tokyo
F. Valentino
Cosmic Dawn Center (DAWN)
T. Wang
National Astronomical Observatory of Japan
University of Tokyo
Monthly Notices of the Royal Astronomical Society
0035-8711 (ISSN) 1365-2966 (eISSN)
Vol. 505 4 4838-4846Subject Categories
Subatomic Physics
Astronomy, Astrophysics and Cosmology
Radiology, Nuclear Medicine and Medical Imaging
DOI
10.1093/mnras/stab191