Naslov
An Ultradeep Multiband VLA Survey of the Faint Radio Sky (COSMOS-XS): Source Catalog and Number Counts

Autori
Van der Vlugt, D. ; Algera, H. S. B. ; Hodge, J. A. ; Novak, Mladen ; Radcliffe, J. F. ; Riechers, D. A. ; Röttgering, H. ; Smolčić, Vernesa ; Walter, F.

Izvornik
The Astrophysical journal (0004-637X) 907 (2021); 5, 19

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Radio source counts ; Radio source catalogs ; Radio continuum emission ; 1357 ; 1356 ; 1340 ; Astrophysics - Astrophysics of Galaxies

Sažetak
We present ultradeep, matched-resolution Karl G. Jansky Very Large Array observations at 10 and 3 GHz in the COSMOS field: the COSMOS-XS survey. The final 10 and 3 GHz images cover ∼16 and ∼180arcmin2 and reach median rms values at the phase center of 0.41 and 0.53 μJy beam-1, respectively. Both images have an angular resolution of ∼2"0. To account for the spectral shape and resolution variations across the broad bands, we image all data with a multiscale, multifrequency synthesis algorithm. We present source catalogs for the 10 and 3 GHz image with 91 and 1498 sources, respectively, above a peak brightness threshold of 5σ. We present source counts with completeness corrections included that are computed via Monte Carlo simulations. Our corrected counts at 3 GHz are consistent within the uncertainties with other results at 3 and 1.4 GHz but extend to fainter flux densities than previous direct detections. The 3 GHz number counts exceed the counts predicted by the semiempirical simulations developed in the framework of the SKA Simulated Skies project, consistent with previous P(D) analyses. Our source counts suggest a steeper luminosity function evolution for faint star-forming sources. The semiempirical Tiered Radio Extragalactic Continuum Simulation predicts this steeper evolution and is in better agreement with our results at 10 and 3 GHz within the expected variations from cosmic variance. In summary, the multiband, matched- resolution COSMOS-XS survey in the COSMOS field provides a high-resolution view of the ultrafaint radio sky that can help guide next-generation radio facilities.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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