The ALPINE-ALMA [CII] survey

Dust mass budget in the early Universe

¹ Dipartimento di Fisica e Astronomia, Universitá of Bologna, via Gobetti 93/2, 40129 Bologna, Italy
e-mail: f.pozzi@unibo.it
² INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna, via Gobetti 93/3, 40129 Bologna, Italy
³ Department of Astronomy, University of Geneva, 51 Ch. des Maillettes, 1290 Versoix, Switzerland
⁴ Aix Marseille Univ. CNRS, LAM, Laboratoire d’Astrophysique de Marseille, Marseille, France
⁵ INAF – Osservatorio astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy
⁶ Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125, USA
⁷ Dipartimento di Fisica e Astronomia, Universitá di Padova, vicolo Osservatorio 3, 35122 Padova, Italy
⁸ The Caltech Optical Observatories, California Institute of Technology, Pasadena, CA 91125, USA
⁹ Kavli Institute for the Physics and Mathematics of the Universe, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba 277-8583, Japan
¹⁰ Centro de Astronomia (CITEVA), Universidad de Antofagasta, Avenida Angamos 601, Antofagasta, Chile
¹¹ Department of Astronomy, University of Florida, 211 Bryant Space Sciences Center, Gainesville, FL 32611, USA
¹² European Southern Observatory, Karl-Schwarzschild-Straße 2, 85748 Garching, Germany
¹³ Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218, USA
¹⁴ Cavendish Laboratory, University of Cambridge, 19 J. J. Thomson Ave., Cambridge CB3 0HE, UK
¹⁵ 16 Kavli Institute for Cosmology, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK
¹⁶ Department of Physics, University of California, Davis, One Shields Ave., Davis, CA 95616, USA
¹⁷ Department of Physics and Astronomy, University College London, London, UK
¹⁸ Department of Astronomy, Cornell University, Space Sciences Buildin, Ithaca, NY 14853, USA
¹⁹ INAF – Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy
²⁰ Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy

Received: 29 December 2020
Accepted: 25 May 2021

Abstract

Aims. The dust content of normal galaxies and the dust mass density (DMD) at high-z (z > 4) are unconstrained given the source confusion and the sensitivity limitations of previous observations. The ALMA Large Program to INvestigate [CII] at Early times (ALPINE), which targeted 118 ultra-violet (UV)-selected star-forming galaxies at 4.4 < z < 5.9, provides a new opportunity to tackle this issue for the first time with a statistically robust dataset.

Methods. We exploited the rest-frame far-infrared (FIR) fluxes of 23 galaxies individually detected in their continuum emission, as well as stacked continuum images, to measure the dust content of the 118 UV-selected ALPINE galaxies. We focused on the dust scaling relations and, by comparison with predictions from chemical evolution models, we probed the evolutionary stage of UV-selected galaxies at high-z. By using the observed correlation between the UV luminosity and the dust mass, we estimated the DMD of UV-selected galaxies at z ∼ 5, weighting the galaxies by means of the UV luminosity function. The derived DMD is compared with the value we estimated from ten ALPINE galaxies blindly detected in the FIR continuum, at the redshift of the ALPINE targets.

Results. Our ALMA survey allows the exploration for the first time of the dust content in normal star-forming galaxies at z > 4 in a statistically robust sample of sources. The comparison of the observed dust scaling relations with chemical evolution models suggests that ALPINE galaxies are not likely progenitors of disc galaxies, but of intermediate- and low-mass proto-spheroids, resulting in present-day bulges of spiral or elliptical galaxies. Interestingly, this conclusion is in line with the independent morphological analysis that shows that the majority (∼70%) of the dust-continuum detected galaxies have a disturbed morphology. The DMD obtained at z ∼ 5 from UV-selected sources is ∼30% of the value obtained from blind FIR-selected sources, showing that the UV selection misses the most dust-rich, UV-obscured galaxies.