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arXiv · 1801.04464

Optical identifications of high-redshift galaxy clusters from Planck Sunyaev-Zeldovich survey

R. A. Burenin·I. F. Bikmaev·I. M. Khamitov·I. A. Zaznobin·G. A. Khorunzhev·M. V. Eselevich·V. L. Afanasyev·S. N. Dodonov·J. A. Rubiño-Martín·N. Aghanim·R. A. Sunyaev
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Abstract

We present the results of optical identifications and spectroscopic redshifts measurements for galaxy clusters from 2-nd Planck catalogue of Sunyaev-Zeldovich sources (PSZ2), located at high redshifts, $z\approx0.7-0.9$. We used the data of optical observations obtained with Russian-Turkish 1.5-m telescope (RTT150), Sayan observatory 1.6-m telescope, Calar Alto 3.5-m telescope and 6-m SAO RAS telescope (Bolshoi Teleskop Alt-azimutalnyi, BTA). Spectroscopic redshift measurements were obtained for seven galaxy clusters, including one cluster, PSZ2 G126.57+51.61, from the cosmological sample of PSZ2 catalogue. In central regions of two clusters, PSZ2 G069.39+68.05 and PSZ2 G087.39-34.58, the strong gravitationally lensed background galaxies are found, one of them at redshift $z=4.262$. The data presented below roughly double the number of known galaxy clusters in the second Planck catalogue of Sunyaev-Zeldovich sources at high redshifts, $z\approx0.8$.

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R. A. Burenin, I. F. Bikmaev, I. M. Khamitov, I. A. Zaznobin, G. A. Khorunzhev, M. V. Eselevich, V. L. Afanasyev, S. N. Dodonov, J. A. Rubiño-Martín, N. Aghanim, R. A. Sunyaev. 2018-01-13. Optical identifications of high-redshift galaxy clusters from Planck Sunyaev-Zeldovich survey. https://doi.org/10.1134/s1063773718050018

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