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VLA M 31 1.4-GHz Source Catalog
This table contains the Data Release 2 of the Point Source Catalog created from a series of previously constructed radio-continuum images of M 31 at a wavelength lambda of 20 cm (frequency nu = 1.4 GHz) from archived VLA observations. In total, the authors identify a collection of 916 unique discrete radio sources across the field of M 31. Comparing these detected sources with those listed by Gelfand et al. (2004, ApJS, 155, 89, HEASARC table VLAM31325M) at lambda = 92 cm (325 MHz), the spectral index of 98 sources has been derived. The majority (73%) of these sources exhibit a spectral index of alpha < -0.6, indicating that their emission is predominantly non-thermal in nature, which is typical for background objects and Supernova Remnants (SNRs). This table contains the integrated flux densities for 1,131 detections of 916 unique sources detected at 1.4 GHz in 28 VLA observations. Of these 916 unique sources, 109 were detected in at least two separate images. For such sources, the authors list a group identifier, a group count, and an average flux and error. Sources were cross referenced with the Gelfand et al. (2004) catalog of sources detected at 92 cm. For matched sources, the flux density at this wavelength and the derived spectral index between 20 and 92 cm are listed. This table was created by the HEASARC in May 2015 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/Other/Ser/189.15">CDS Catalog J/Other/Ser/189.15</a> file m31radio.dat. This is a service provided by NASA HEASARC .
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20cm Radio Catalog
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The 1.4-GHz Northern Sky Catalog - Version: 4 December 1991 This is the 20-cm Northern Sky Catalog of White, R. L. and Becker, R. H. (1992, Ap.J.Supp., in press) containing 30,239 sources detected from the Condon Greenbank images taken at 1.4 GHz over the declination range of -5 degrees to 82 degrees with a flux density limit of 100 mJy. This 20 cm catalog also contains the results of a cross-correlation with catalogs at 6 and 80 cm covering the northern sky between Dec=0 degrees and 70 degrees to give the spectral indices at three frequencies for about 20,000 sources. This is a service provided by NASA HEASARC .
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 .