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Description
This table contains a final unified catalog for the 7C survey at 151 MHz with a spatial resolution of 70 x 70cosec(Dec) arcsec<sup>2</sup>. This has been constructed by amalgamating the existing catalogs derived from individual fields imaged at this resolution and eliminating redundancy in regions of mutual overlap. This was a non-trivial procedure because the flux in multiple-component sources may be fitted differently on alternative images, owing, for example, to differences in local noise and beam distortion. The final catalog as published thus produced contains 43683 sources. (Note that the HEASARC removed one duplicate source entry for '7C 083231.6+262635' since it had two entries, which were identical except that in one the beam-fitted flux density S<sub>bf</sub> was 834 mJy/beam, while, in the other entry now removed, S<sub>bf</sub> was 840 mJy/beam). Separate final catalogs have been previously published for the 7C Galactic Plane 7CG survey (available as the HEASARC table GP7C151MHZ), and the lower-resolution survey of the low-declination strip 9<sup>h</sup> < RA < 16<sup>h</sup>, 20<sup>o</sup> < Dec < 35<sup>o</sup> (available as the HEASARC table LD7C151MHZ). The individual catalogs for about 40 of the 96 regions contributing to the total have already been published, together with full details of the methodology, in MNRAS or A&AS: <pre> Reference Region Lacy et al. 1995, MNRAS, 276, 614 92 Visser et al. 1995, A&AS, 110, 419 93 Pooley et al. 1998, MNRAS, 298, 637 94-96 Riley et al. 1999, MNRAS, 306, 31 1-33 </pre> and these data are also available via the MRAO website: <a href="http://www.mrao.cam.ac.uk/surveys/7C/">http://www.mrao.cam.ac.uk/surveys/7C/</a> Individual catalogs for the remaining 58 regions by Riley et al. (regions 34-91) were released electronically via the MRAO website in November 2001. These include a re-analysis of data originally published in rather a different parametrization by McGilchrist et al. 1990, MNRAS, 246, 110. The regions re-analyzed are those numbered 41, 44, 59, 60, 62 and 63 and they supersede McGilchrist's 1990 publication. The RA x Dec coverage, the average rms noise, the flux density of the faintest source listed and the completeness limit for each of the individual regions contributing to the final catalog are given in the table <a href="http://cdsarc.u-strasbg.fr/ftp/cats/J_MNRAS/382/1639/regions.dat">http://cdsarc.u-strasbg.fr/ftp/cats/J_MNRAS/382/1639/regions.dat</a>. For further details of the surveys and data analysis procedures please refer to the published papers referenced above and other references contained therein. This table was created by the HEASARC in October 2010 based on CDS table J/MNRAS/382/1639 files 7c.dat and regions.dat. This is a service provided by NASA HEASARC .
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