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Radio sources associated with Optical Galaxies and having Unresolved or Extended morphologies (ROGUE). I. A catalog of SDSS galaxies with FIRST core identifications

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 نشر من قبل Dorota Kozie{\\l}-Wierzbowska
 تاريخ النشر 2019
  مجال البحث فيزياء
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We present the catalog of Radio sources associated with Optical Galaxies and having Unresolved or Extended morphologies I (ROGUE~I), consisting of 32,616 spectroscopically selected galaxies. It is the largest handmade catalog of this kind, obtained by cross-matching galaxies from the Sloan Digital Sky Survey (SDSS) Data Release 7 and radio sources from both the First Images of Radio Sky at Twenty Centimetre (FIRST) survey and the NRAO VLA Sky Survey textit{without imposing a limit to the radio flux densities}. The catalog provides a textit{visual} classification of radio and optical morphologies of galaxies presenting a FIRST core within 3arcsec of the optical position. The radio morphological classification is performed by examining the radio-optical overlays of linear sizes equal to 1 Mpc at the source distance, while the 120arcsec image snapshots from the SDSS database are used for optical classification. The results of our search are: (i) single-component unresolved and elongated, radio sources constitute the major group in the ROGUE I catalog ($sim$90%), and $sim$8% exhibiting {it extended} morphologies, (ii) samples of 269, 730, and 115 Fanaroff-Riley (FR) type I, II, and hybrid galaxies, respectively, are presented (iii) we report 55 newly discovered giant/possible giant, 16 double-double, 9 X-shaped, and 25 Z-shaped radio sources, (iv) on the optical front, most galaxies have elliptical morphologies ($sim$62%) while spirals form the second major category ($sim$17%) followed by distorted ($sim$ 12%) and lenticular ($sim$7%) morphologies, (v) division between the FR I and the FR~II sources in the radio-optical luminosity plane is blurred, in tune with recent studies.



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