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The VLA-COSMOS 3 GHz large project: the cosmic star-formation history since z ~ 5

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posted on 2023-06-09, 05:03 authored by M Novak, V Smolcic, J Delhaize, I Delvecchio, G Zamorani, N Baran, M Bondi, P Capak, C L Carilli, P Ciliegi, Mark Sargent, et al
We make use of the deep Karl G. Jansky Very Large Array (VLA) COSMOS radio observations at 3 GHz to infer radio luminosity functions of star-forming galaxies up to redshifts of z~5 based on approximately 6000 detections with reliable optical counterparts. This is currently the largest radio-selected sample available out to z~5 across an area of 2 square degrees with a sensitivity of rms=2.3 ujy/beam. By fixing the faint and bright end shape of the radio luminosity function to the local values, we find a strong redshift trend that can be fitted with a pure luminosity evolution L~(1+z)^{(3.16 +- 0.2)-(0.32 +- 0.07) z}. We estimate star formation rates (SFRs) from our radio luminosities using an infrared (IR)-radio correlation that is redshift dependent. By integrating the parametric fits of the evolved luminosity function we calculate the cosmic SFR density (SFRD) history since z~5. Our data suggest that the SFRD history peaks between 21000 Msol/yr) contribute an additional <2% in the entire observed redshift range. We find evidence of a potential underestimation of SFRD based on ultraviolet (UV) rest-frame observations of Lyman break galaxies (LBGs) at high redshifts (z>4) on the order of 15-20%, owing to appreciable star formation in highly dust-obscured galaxies, which might remain undetected in such UV observations.

History

Publication status

  • Published

File Version

  • Accepted version

Journal

Astronomy and Astrophysics

ISSN

0004-6361

Publisher

EDP Sciences

Volume

602

Article number

a5

Department affiliated with

  • Physics and Astronomy Publications

Research groups affiliated with

  • Astronomy Centre Publications

Full text available

  • Yes

Peer reviewed?

  • Yes

Legacy Posted Date

2017-06-06

First Open Access (FOA) Date

2017-06-21

First Compliant Deposit (FCD) Date

2017-06-05

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