Investigation of radio sources with the virtual observatory tools: Results and problems.

Radio sources of the RCR catalogue, obtained from observational data of the 'Cold' experiment, have been identified, almost completely, with optical objects. For this purpose, we used optical, infrared, and radio sky surveys as well as archive data from the VLA (NRAO) and the 6-m telescope (SAO). According to spectroscopy and color index constraints, the identified sources are classified as galaxies and quasars; about 20 % of the sources remain unclassified because of being optically faint. We estimated radio luminosities of the sources and found that a majority (60%) of them belong to strong radio sources. Using ratios of FIRST and NVSS flux densities and angular sizes, we prepared a sample of steep spectrum compact sources. The existing infrastructure of the virtual observatory increases the effectiveness of astronomical studies like ours greatly. However, we still cannot consider the virtual observatory a completed project because it requires further development of services providing actualization of user data and better semantic compatibility of information. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]