Alexander I. Kopylov

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.

TL;DR: In this article, a possibility has been investigated of using two evolutionary models of stellar systems (PEGASE and Poggianti) to evaluate readshifts and ages of stellar system in these galaxies.

TL;DR: The properties of galaxies with quenched star formation (QGs) within the splashback radius of galaxy clusters Rsp and beyond it have been studied in this paper based on the SDSS catalog data.

TL;DR: In this paper, the authors studied the variations of the properties of groups of galaxies with dynamical masses of 1013m, and found that the fraction of early-type galaxies in the considered systems is equal, on average, to 0.65 ± 0.01, and varies significantly for galaxies with σ200 < 300 kms−1.