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arXiv · 2304.03058

A VLT/VIMOS view of two $Planck$ multiple-cluster systems: structure and galaxy properties

R. Wicker·N. Aghanim·V. Bonjean·E. Lecoq·M. Douspis·D. Burgarella·E. Pointecouteau
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Abstract

We analysed spectroscopic data obtained with VLT-VIMOS for two multiple-cluster systems, PLCKG$214.6+36.9$ and PLCKG$334.8-38.0$, discovered via their thermal Sunyaev-Zel'dovich signal by $Planck$. Combining the Optical spectroscopy, for the redshift determination, and photometric data from galaxy surveys (SDSS, WISE, DESI), we were able to study the structure of the two multiple-cluster systems, to determine their nature and the properties of their member galaxies. We found that the two systems are populated mainly with passive galaxies and that PLCKG$214.6+36.9$ consists of a pair of clusters at redshift $z = 0.445$ and a background isolated cluster at $z = 0.498$, whereas the system PLCKG$334.8-38.0$ is a chance association of three independent clusters at redshifts $z = 0.367$, $z =0.292$, and $z = 0.33$. We also find evidence for remaining star formation activity in the highest-redshift cluster of PLCKG$214.6+36.9$, at $z = 0.498$.

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R. Wicker, N. Aghanim, V. Bonjean, E. Lecoq, M. Douspis, D. Burgarella, E. Pointecouteau. 2023-04-06. A VLT/VIMOS view of two $Planck$ multiple-cluster systems: structure and galaxy properties. https://doi.org/10.1051/0004-6361/202346608

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