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Photometric study of radio galaxies in RATAN--600 "Cold" survey

O. V. Verkhodanov·Yu. N. Parijskij·N. S. Soboleva·A. I. Kopylov·A. V. Temirova·O. P. Zhelenkova·W. M. Goss
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Abstract

About 100 steep spectrum radio sources from the RATAN--600 RC catalog were mapped by the VLA and identified with optical objects down to 24$^m$--25$^m$ in the R band using the 6 m telescope. An updated list of calibrators with known redshifts of the same class RGs was compiled to evaluate the accuracy of photometric redshifts estimates. BVRI photometry for 60 RC objects was performed with the 6 m telescope, and by standard model fitting we have estimated colour redshifts and ages of stellar population of host gE galaxies. The mean redshift of FRII RGs from the RC list happened to be $\approx$1. Several objects were found in which active star formation began in the first billion years after the Big Bang.

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O. V. Verkhodanov, Yu. N. Parijskij, N. S. Soboleva, A. I. Kopylov, A. V. Temirova, O. P. Zhelenkova, W. M. Goss. 2001-12-06. Photometric study of radio galaxies in RATAN--600 "Cold" survey. https://arxiv.org/abs/astro-ph/0112144

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