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VLA-VIRMOS Deep Field 20-cm Source Catalog
The authors of this table conducted a deep survey (rms noise ~ 17 microJansky or uJy) with the Very Large Array (VLA) at 1.4 GHz, with a resolution of 6 arcseconds, of a 1 deg<sup>2</sup> region included in the VIRMOS VLT Deep Survey that is centered at RA and Dec (J2000.0) of 02 26 00, -04 30 00, hereafter the VLA-VIRMOS Deep Field, or VLA-VDF. In the same field, they already had multiband photometry down to I<sub>AB</sub> = 25, and spectroscopic observations were to be obtained during the VIRMOS VLT survey. The homogeneous sensitivity over the whole field allowed them to derive a complete sample of 1054 radio sources (5-sigma limit) down to a limit of 0.08 mJy. In their paper, the authors give a detailed description of the data reduction and of the analysis of the radio observations, with particular care to the effects of clean bias and bandwidth smearing, and of the methods used to obtain the catalog of radio sources. To estimate the effect of the resolution bias on their observations, they have modeled the effective angular-size distribution of the sources in their sample and they have used this distribution to simulate a sample of radio sources. Finally, they present the radio count distribution down to 0.08 mJy derived from the catalog. Their counts are in good agreement with the best fit derived from earlier surveys, and are about 50% higher than the counts in the Hubble Deep Field (HDF). The radio count distribution clearly shows, with extremely good statistics, the change in the slope for the sub-mJy radio sources. 19 of the 1054 radio sources were fitted with multiple components. In such cases, the authors list in the catalog an entry for each of the components, identified with a trailing letter (A, B, C or D) in the source name, and an entry for the whole source, identified with a trailing T in the source name. In these cases the total flux was calculated using the task TVSTAT, which allows the integration of the map values over irregular areas, and the sizes are the largest angular sizes. Thus, this catalog contains 1103 entries on 1054 sources, including 49 entries on individual components of composite sources. This table was created by the HEASARC in February 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/403/857">CDS Catalog J/A+A/403/857</a> file catalog.dat. This is a service provided by NASA HEASARC .
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ROSAT/XMM-Newton 13-hr Deep Field VLA 20-cm Source Catalog
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In order to determine the relationship between the faint X-ray and faint radio source populations, and hence to help understand the X-ray and radio emission mechanisms in those faint source populations, the authors have made a deep 1.4-GHz Very Large Array radio survey of the 13h 34m 37s, +37o 54' 44" (J2000) ROSAT/XMM-Newton X-ray Survey Area (McHardy et al. 1998, MNRAS, 295, 641; Loaring et al. 2005, MNRAS, 362, 1371: the catalog of XMM-Newton sources from the latter paper is available at the HEASARC as the ROS13HRXMM table). From a combined VLA data set of 10 hours of B-configuration data and 14 hours of A-configuration data, maps with 3.35-arcsec resolution and a noise limit of 7.5 microJansky (µJy) were constructed. A complete sample of 449 sources was detected within a 30-arcmin diameter region above a 4-sigma detection limit of 30 uJy, at the map center, making this one of the deepest radio surveys at this frequency. The differential source count shows a significant upturn at sub-milliJansky flux densities, similar to that seen in other deep surveys at 1.4 GHz (e.g. the Phoenix survey, Hopkins et al. 2003, AJ, 125, 465: available at the HEASARC as the PDS1P4GHZ table), but larger than that seen in the Hubble Deep Field (HDF) which may have been selected to be underdense. This upturn is well modeled by the emergence of a population of medium-redshift star-forming galaxies which dominate at faint flux densities. The brighter source counts are well modeled by active galactic nuclei. This HEASARC table contains the catalog of 449 radio sources in a region of 30-arcmin diameter centered on the ROSAT/XMM 13-hours field which were detected at 1.4 GHz (20 cm) above a detection threshold of 4 sigma, equivalent to 30 uJy at the phase center. This table was created by the HEASARC in July 2013 based on CDS Catalog J/MNRAS/352/131 file table a1.dat. This is a service provided by NASA HEASARC .
BeppoSAX High-Energy Large Area Survey (HELLAS) Radio Source Catalog
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This table contains results of a complete radio follow-up obtained with the VLA and ATCA radio telescopes down to a 6-cm flux limit of about 0.3 mJy (3-sigma) of all the 147 X-ray sources detected in the BeppoSAX HELLAS survey (Fiore et al. 2001, MNRAS, 327, 771). The authors found 53 X-ray/radio likely associations, corresponding to about one-third of the X-ray sample. Using the two-point spectral index alpharo = 0.35 they divided all the HELLAS X-ray sources into radio-quiet and radio-loud. They have 26 sources classified as radio-loud objects, corresponding to 18 per cent of the HELLAS sample. In agreement with previous results, the identified radio-loud sources are associated mainly with Type 1 active galactic nuclei (AGNs) with L5-10keV >~ 1044 erg/s, while all the identified Type 2 AGNs and emission-line galaxies are radio-quiet objects with L5-10keV <~ 1044 erg/s. The 20 HELLAS sources with Declinations south of -40o were observed with the ATCA, while the 127 sources with more northerly Declinations were observed with the VLA. For these latter sources a complete covering at 20 cm down to the 5-sigma flux limit of 2.5 mJy is already available with the NRAO/VLA Sky Survey (NVSS) while the FIRST survey (Faint Images of the Radio Sky at Twenty centimeters) is available only for 27 HELLAS sources (5-sigma limit of ~ 1 mJy).In order to obtain information also on the radio spectral properties of the HELLAS sources the authors adopted the following strategy. All the 147 HELLAS sources were observed at 6 cm down to a 1 -sigma flux limit of ~ 0.10 - 0.25 mJy. For the 20 HELLAS sources observed with the ATCA, they took advantage of the fact that the 6 and 3 cm receivers of the ATCA share a common feed-horn and they observed simultaneously also at 3 cm, obtaining a 3-cm flux limit of ~ 0.22 mJy (1-sigma level). Starting from the radio position of the 53 X-ray/radio associations, the authors searched for optical counterparts within 5 arcseconds from the radio position using the optical positions of the 61 HELLAS sources identified by La Franca et al. (2002, ApJ, 570, 100 = LF02), the USNO-A2.0 1 optical catalog, the APM 2 optical catalog and the NASA Extragalactic Database (NED). 24 X-ray/radio associations have been identified with sources in LF02 (10 Type 1 AGN, 4 Type 2 AGN, 2 BL Lacs, 3 Clusters, 4 ELGs and 1 Radio galaxy), 1 has been identified with a z = 0.708 Radio galaxy in the Lockman Hole using NED (see Table 2 source 116 in Lehmann et al. 2000, A&A, 354, 35 for a description of this source), 13 have an optical (R-band) identification in the USNO and/or APM catalogue while 15 X-ray/radio associations do not have an optical identification brighter than R=20. This table was created by the HEASARC in July 2014 based on CDS Catalog J/MNRAS/342/575 file table1.dat. There was a minor update to the HEASARC's implementation in June 2022 to make the two probability parameters into unitless quantities for improved clarity. This is a service provided by NASA HEASARC .
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