z -GAL: A NOEMA spectroscopic redshift survey of bright Herschel galaxies: III. Physical properties
Journal article, 2023

The z-GAL survey observed 137 bright Herschel-selected targets with the IRAM Northern Extended Millimeter Array, with the aim to measure their redshift and study their properties. Several of them have been resolved into multiple sources. Consequently, robust spectroscopic redshifts have been measured for 165 individual galaxies in the range 0.8., <., z., <., 6.5. In this paper we analyse the millimetre spectra of the z-GAL sources, using both their continuum and line emission to derive their physical properties. At least two spectral lines are detected for each source, including transitions of 12CO, [CI], and H2O. The observed 12CO line ratios and spectral line energy distributions of individual sources resemble those of local starbursts. In seven sources the para-H2O (211-202) transition is detected and follows the IR versus H2O luminosity relation of sub-millimetre galaxies. The molecular gas mass of the z-GAL sources is derived from their 12CO, [CI], and sub-millimetre dust continuum emission. The three tracers lead to consistent results, with the dust continuum showing the largest scatter when compared to 12CO. The gas-to-dust mass ratio of these sources was computed by combining the information derived from 12CO and the dust continuum and has a median value of 107, similar to star-forming galaxies of near-solar metallicity. The same combined analysis leads to depletion timescales in the range between 0.1 and 1.0 Gyr, which place the z-GAL sources between the main sequence' of star formation and the locus of starbursts. Finally, we derived a first estimate of stellar masses "modulo possible gravitational magnification "by inverting known gas scaling relations: the z-GAL sample is confirmed to be mostly composed by starbursts, whereas ∼25% of its members lie on the main sequence of star-forming galaxies (within ±0.5 dex).

Galaxies: high-redshift

Galaxies: ISM

Submillimeter: galaxies

Galaxies: star formation

Galaxies: statistics

Galaxies: starburst

Author

S. Berta

Institut de Radioastronomie Millimétrique (IRAM)

F. Stanley

Institut de Radioastronomie Millimétrique (IRAM)

D. Ismail

Laboratoire d'Astrophysique de Marseille

P. Cox

Institut d 'Astrophysique de Paris

R. Neri

Institut de Radioastronomie Millimétrique (IRAM)

Chentao Yang

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

A. J. Young

Rutgers University

S. Jin

Cosmic Dawn Center (DAWN)

Technical University of Denmark (DTU)

H. Dannerbauer

Instituto de Astrofísica de Canarias

University of La Laguna

Tom Bakx

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

National Astronomical Observatory of Japan

Nagoya University

A. Beelen

Laboratoire d'Astrophysique de Marseille

A. Weiß

Max Planck Society

A. Nanni

Istituto nazionale di astrofisica (INAF)

Narodowe Centrum Badan Jadrowych

A.A. Omont

Institut d 'Astrophysique de Paris

P. van der Werf

Leiden University

M. Krips

Institut de Radioastronomie Millimétrique (IRAM)

A. J. Baker

Rutgers University

University of the Western Cape

G. J. Bendo

University of Manchester

E. Borsato

University of Padua

V. Buat

Laboratoire d'Astrophysique de Marseille

K. M. Butler

Institut de Radioastronomie Millimétrique (IRAM)

N. Chartab

University of California at Irvine (UCI)

A. Cooray

University of California at Irvine (UCI)

S. Dye

University of Nottingham

S. Eales

Cardiff University

R. Gavazzi

Institut d 'Astrophysique de Paris

D. Hughes

National Institute of Astrophysics, Optics and Electronics

R. J. Ivison

Dublin Institute for Advanced Studies

University of Edinburgh

Macquarie University

European Southern Observatory (ESO)

B. M. Jones

University of Cologne

M. Lehnert

CRAL Le Centre de Recherche Astronomique de Lyon

L. Marchetti

Istituto di Radioastronomia

University of Cape Town

H. Messias

Atacama Large Millimeter-submillimeter Array (ALMA)

European Southern Observatory Santiago

M. Negrello

Cardiff University

I. Perez-Fournon

Instituto de Astrofísica de Canarias

University of La Laguna

D. A. Riechers

University of Cologne

S. Serjeant

Open University

S. Urquhart

Open University

C. Vlahakis

National Radio Astronomy Observatory

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 678 A28

Exploring the Hidden Dusty Nuclei of Galaxies (HIDDeN)

European Research Council (ERC) (789410), 2018-10-01 -- 2023-09-30.

Subject Categories

Astronomy, Astrophysics and Cosmology

DOI

10.1051/0004-6361/202346803

More information

Latest update

10/30/2023