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Optical morphology of distant RATAN-600 radio galaxies from subarcsecond resolution NOT images

T. Pursimo·K. Nilsson·P. Teerikorpi·A. Kopylov·N. Soboleva·Yu. Parijskij·Yu. Baryshev·O. Verhodanov·A. Temirova·O. Zhelenkova·W. Goss·A. Sillanpää·L. O. Takalo
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Abstract

We present direct imaging data of 22 ultra steep spectrum radio sources obtained at (or near) a subarcsecond seeing. The basic sample of 40 double radio sources was selected from the RATAN-600 catalogue. The FRII-structure has been confirmed with VLA and preliminary optical identifications which come from the 6 m-telescope. As the RATAN-600 flux limit at 3.9 GHz ($\approx$ 10mJy) is fainter than that of major surveys, the sample may have high-$z$ contents. This is also suggested by the faint magnitudes in the Hubble diagram. The final aim is to create a homogeneous sample of high-$z$ radio galaxies in a well defined strip around the sky, with faint radio limit and subarcsecond morphology down to $m_{R}=24$. We could confirm 16 identifications down to $m_{R}\sim$24. Most of the extended objects have multicomponent structures as expected from other surveys of high-redshift radio galaxies. We found five unresolved objects even with a subarcsecond seeing. Of the remaining six objects, three are extremely faint and the other three have such a complex environment that further observations are needed to confirm the optical identification.

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T. Pursimo, K. Nilsson, P. Teerikorpi, A. Kopylov, N. Soboleva, Yu. Parijskij, Yu. Baryshev, O. Verhodanov, A. Temirova, O. Zhelenkova, W. Goss, A. Sillanpää, L. O. Takalo. 1998-11-19. Optical morphology of distant RATAN-600 radio galaxies from subarcsecond resolution NOT images. https://doi.org/10.1051/aas%3A1999152

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