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A new version of the OCARS catalog of Optical Characteristics of Astrometric Radio Sources

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 Added by Zinovy Malkin
 Publication date 2018
  fields Physics
and research's language is English
 Authors Zinovy Malkin




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A new version of the Optical Characteristics of Astrometric Radio Sources (OCARS) catalog is presented. This compiled catalog includes radio sources observed in different VLBI programs and experiments that result in source position determination, their redshift, and photometry in the visible and near-infrared bands. A cross-identification table between the OCARS and other catalogs is also provided. The status of the catalog as of 2018 September 7 is described in this paper. The OCARS catalog currently contains 6432 sources, of which 3895 have redshift data and 5479 have photometric data. Compared with the previous version, the current version has been enriched with extended redshift and photometry information, and cross-identification with several catalogs in radio, optical, infrared, ultraviolet, X-ray, and gamma-ray bands. The OCARS catalog is updated every few weeks on average to incorporate new data that appear in the NASA/IPAC Extragalactic Database (NED), SIMBAD database, and in the literature.



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129 - Zinovy Malkin 2021
A comparison was made between $Gaia$ magnitudes and magnitudes obtained from ground-based observations for astrometric radio sources . The comparison showed that these magnitudes often not agree well. There may be several reasons for this disagreement. Nevertheless, such an analysis can serve as an additional filter for verification of the object cross-identification. On the other hand, it can help to detect possible errors in optical magnitudes of astrometric radio sources coming from unreliable or inconsistent data sources.
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127 - J. Xu 2014
We compiled a catalog of Faraday rotation measures (RMs) for 4553 extragalactic radio point sources ublished in literature. These RMs were derived from multi-frequency polarization observations. The RM data are compared to those in the NRAO VLA Sky Survey (NVSS) RM catalog. We reveal a systematic uncertainty of about $10.0 pm 1.5$,rad~m$^{-2}$ in the NVSS RM catalog. The Galactic foreground RM is calculated through a weighted averaging method by using the compiled RM catalog together with the NVSS RM catalog, with careful consideration of uncertainties in the RM data. The data from the catalog and the interface for the Galactic foreground RM calculations are publicly available on the webpage: http://zmtt.bao.ac.cn/RM/.
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