Molecular gas and dust properties of galaxies from the Great Observatories All-sky LIRG Survey
Journal article, 2019

We present IRAM-30 m Telescope (CO)-C-12 and (CO)-C-13 observations of a sample of 55 luminous and ultraluminous infrared galaxies (LIRGs and ULIRGs) in the local universe. This sample is a subset of the Great Observatory All-Sky LIRG Survey (GOALS), for which we use ancillary multi-wavelength data to better understand their interstellar medium and star formation properties. Fifty-three (96%) of the galaxies are detected in (CO)-C-12, and 29 (52%) are also detected in (CO)-C-13 above a 3 sigma level. The median full width at zero intensity (FWZI) velocity of the CO line emission is 661 km s(-1), and similar to 54% of the galaxies show a multi-peak CO profile. Herschel photometric data is used to construct the far-IR spectral energy distribution of each galaxy, which are fit with a modified blackbody model that allows us to derive dust temperatures and masses, and infrared luminosities. We make the assumption that the gas-to-dust mass ratio of (U)LIRGs is comparable to local spiral galaxies with a similar stellar mass (i.e., gas/dust of mergers is comparable to their progenitors) to derive a CO-to-H-2 conversion factor of = 1.8(-0.8)(+1.3) M-circle dot (K km s(-1) pc(2))(-1); such a value is comparable to that derived for (U)LIRGs based on dynamical mass arguments. We derive gas depletion times of 400 600 Myr for the (U)LIRGs, compared to the 1.3 Gyr for local spiral galaxies. Finally, we re-examine the relationship between the (CO)-C-12/(CO)-C-13 ratio and dust temperature, confirming a transition to elevated ratios in warmer systems.

galaxies: starburst

galaxies: active

ISM: molecules

radio lines: galaxies

galaxies: ISM

Author

R. Herrero-Illana

ESO

Spanish National Research Council (CSIC)

G. C. Privon

Pontificia Universidad Catolica de Chile

University of Florida

A. S. Evans

Natl Radio Astron Observ

University of Virginia

T. Diaz-Santos

Universidad Diego Portales

M. A. Perez-Torres

Univ Zaragoza, Fac Ciencias, Zaragoza, Spain; Univ Calif Irvine, Dept Phys & Astron, 4129 Frederick Reines Hall

Spanish National Research Council (CSIC)

A. Alberdi

Spanish National Research Council (CSIC)

K. Iwasawa

University of Barcelona

L. Armus

California Institute of Technology (Caltech)

Susanne Aalto

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

J. Mazzarella

California Institute of Technology (Caltech)

J. Chu

Gemini Observatory North

D. B. Sanders

Atacama Large Millimeter-submillimeter Array (ALMA)

University of Hawaii

L. Barcos-Munoz

University of Virginia

Natl Radio Astron Observ

V Charmandaris

Natl Observ Athens

S. T. Linden

University of Virginia

I Yoon

Natl Radio Astron Observ

D. T. Frayer

Green Bank Observ

H. Inami

NOAA, 950 North Cherry Ave

D-C Kim

Natl Radio Astron Observ

H. J. Borish

University of Virginia

John Conway

Chalmers, Space, Earth and Environment, Onsala Space Observatory

E. J. Murphy

Natl Radio Astron Observ

California Institute of Technology (Caltech)

Y. Song

University of Virginia

S. Stierwalt

California Institute of Technology (Caltech)

J. Surace

California Institute of Technology (Caltech)

Astronomy and Astrophysics

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

Vol. 628 A71

Subject Categories

Analytical Chemistry

Astronomy, Astrophysics and Cosmology

Atom and Molecular Physics and Optics

DOI

10.1051/0004-6361/201834088

More information

Latest update

6/10/2020