High Gas Fraction in a CO-detected Main-sequence Galaxy at z > 3

  • Gowardhan A
  • Riechers D
  • Pavesi R
  • et al.
20Citations
Citations of this article
22Readers
Mendeley users who have this article in their library.

Abstract

We report NOrthern Extended Millimetre Array (NOEMA) observations of warm molecular gas traced by CO(5 − 4) in a z ∼ 3.2 gas-rich main-sequence (MS) galaxy, initially serendipitously detected in CO(3 − 2) emission in “blind” deep NOEMA observations. Our target shows a gas excitation consistent with that seen in z ∼ 1.5 MS galaxies ( L CO ( 5 − 4 ) ′ / L CO ( 3 − 2 ) ′ = 0.41 ± 0.14 ), albeit toward the low end, as well as a similar star formation efficiency based on the CO(3 − 2) line luminosity and the L IR . However, it shows a high molecular gas fraction ( f gas = 0.9 ± 0.2 ) as compared to z ∼ 1.5 MS galaxies ( f gas ∼ 0.42 ), consistent with a cosmologically increasing gas fraction beyond z ≳ 3 and our current understanding of scaling relations between z , f gas , the stellar mass M * , and the specific star formation rate. Our results are consistent with recent findings by the COLDz and ASPECS molecular line scan surveys, and suggest that deep searches for CO emission are a powerful means to identify gas-rich, star-forming galaxies at high redshift.

Cite

CITATION STYLE

APA

Gowardhan, A., Riechers, D., Pavesi, R., Daddi, E., Dannerbauer, H., & Neri, R. (2019). High Gas Fraction in a CO-detected Main-sequence Galaxy at z > 3. The Astrophysical Journal, 875(1), 6. https://doi.org/10.3847/1538-4357/ab0b3c

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free