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arXiv · 1912.09959

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

Abstract

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 3\arcsec\ 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 120\arcsec\ 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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Dorota Kozieł-Wierzbowska, Arti Goyal, Natalia Żywucka. 2019-12-20. Radio sources associated with Optical Galaxies and having Unresolved or Extended morphologies (ROGUE). I. A catalog of SDSS galaxies with FIRST core identifications. https://doi.org/10.3847/1538-4365%2Fab63d3

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