The XXL Survey

Vernesa Smolčić (1) , Huib Intema (2) , Bruno Šlaus (1) , Somak Raychaudhury (3, 4) , Mladen Novak (1) , Cathy Horellou (5) , Lucio Chiappetti (6) , Jacinta Delhaize (1) , Mark Birkinshaw (7) , Marco Bondi (8) , Malcolm Bremer (7) , Paolo Ciliegi (8) , Chiara Ferrari (9) , Konstantinos Kolokythas (3) , Chris Lidman (10) , Sean L. Mcgee (3) , Ray Norris (11, 12) , Marguerite Pierre (13) , Huub Röttgering (2) , Cyril Tasse (14) , Wendy Williams (15)

1 University of Zagreb
2 Leiden Observatory [Leiden]
3 IUCAA - Inter-University Centre for Astronomy and Astrophysics [Pune]
4 University of Birmingham [Birmingham]
5 OSO - Onsala Space Observatory
6 IASF-MI - Istituto di Astrofisica Spaziale e Fisica Cosmica - Milano
7 University of Bristol [Bristol]
8 OABO - INAF - Osservatorio Astronomico di Bologna
9 Observatoire de la Côte d'Azur
10 Australian Astronomical Observatory
11 Western Sydney University
12 CSIRO Astronomy and Space Science
13 AIM (UMR7158 / UMR_E_9005 / UM_112) - Astrophysique Interprétation Modélisation
14 GEPI - Galaxies, Etoiles, Physique, Instrumentation
15 UH - University of Hertfordshire [Hatfield]

We present the 25 square-degree GMRT-XXL-N 610 MHz radio continuum survey, conducted at 50 cm wavelength with the Giant Metrewave Radio Telescope (GMRT) towards the XXL Northern field (XXL-N). We combined previously published observations of the XMM-Large Scale Structure (XMM-LSS) field, located in the central part of XXL-N, with newly conducted observations towards the remaining XXL-N area, and imaged the combined data-set using the Source Peeling and Atmospheric Modeling (SPAM) pipeline. The final mosaic encompasses a total area of 30.4 square degrees, with rms <150 μJy beam−1 over 60% of the area. The rms achieved in the inner 9.6 square degree area, enclosing the XMM-LSS field, is about 200 μJy beam−1, while that over the outer 12.66 square degree area (which excludes the noisy edges) is about 45 μJy beam−1. The resolution of the final mosaic is 6.5 arcsec. We present a catalogue of 5434 sources detected at ≥7 ×rms. We verify, and correct the reliability of, the catalog in terms of astrometry, flux, and false detection rate. Making use of the (to date) deepest radio continuum survey over a relatively large (2 square degree) field, complete at the flux levels probed by the GMRT-XXL-N survey, we also assess the survey’s incompleteness as a function of flux density. The radio continuum sensitivity reached over a large field with a wealth of multi-wavelength data available makes the GMRT-XXL-N 610 MHz survey an important asset for studying the physical properties, environments and cosmic evolution of radio sources, in particular radio-selected active galactic nuclei (AGN).

Mots clés: galaxies: active; catalogs; surveys

Domaines: Astrophysique [astro-ph]

Vernesa Smolčić, Huib Intema, Bruno Šlaus, Somak Raychaudhury, Mladen Novak, et al.. The XXL Survey: XXIX. GMRT 610 MHz continuum observations. Astronomy and Astrophysics - A&A, 2018, 620, pp.A14. ⟨10.1051/0004-6361/201732336⟩. ⟨cea-02498180⟩