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arXiv · 2109.07836

The eROSITA Final Equatorial-Depth Survey (eFEDS): A complete census of X-ray properties of Subaru Hyper Suprime-Cam weak lensing shear-selected clusters in the eFEDS footprint

Miriam E. Ramos-Ceja·M. Oguri·S. Miyazaki·V. Ghirardini·I. Chiu·N. Okabe·A. Liu·T. Schrabback·D. Akino·Y. E. Bahar·E. Bulbul·N. Clerc·J. Comparat·S. Grandis·M. Klein·Y. -T. Lin·A. Merloni·I. Mitsuishi·H. Miyatake·S. More·K. Nandra·A. J. Nishizawa·N. Ota·F. Pacaud·T. H. Reiprich·J. S. Sanders
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Abstract

The eFEDS survey is a proof-of-concept mini-survey designed to demonstrate the survey science capabilities of SRG/eROSITA. It covers an area of 140 square degrees where 542 galaxy clusters have been detected out to a redshift of 1.3. The eFEDS field is partly embedded in the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) S19A data release, which covers 510 square degrees, containing approximately 36 million galaxies. This galaxy catalogue is used to construct a sample of 180 shear-selected galaxy clusters. In the common area to both surveys, about 90 square degrees, we investigate the effects of selection methods in the galaxy cluster detection by comparing the X-ray selected, eFEDS, and the shear-selected, HSC-SSP S19A, galaxy cluster samples. There are 25 shear-selected clusters in the eFEDS footprint. The relation between X-ray bolometric luminosity and weak-lensing mass is investigated, and it is found that the normalization of the bolometric luminosity and mass relation of the X-ray selected and shear-selected samples is consistent within $1\sigma$. Moreover, we found that the dynamical state and merger fraction of the shear-selected clusters is not different from the X-ray selected ones. Four shear-selected clusters are undetected in X-rays. A close inspection reveals that one is the result of projection effects, while the other three have an X-ray flux below the ultimate eROSITA detection limit. Finally, 43% of the shear-selected clusters lie in superclusters. Our results indicate that the scaling relation between X-ray bolometric luminosity and true cluster mass of the shear-selected cluster sample is consistent with the eFEDS sample. There is no significant population of X-ray underluminous clusters, indicating that X-ray selected cluster samples are complete and can be used as an accurate cosmological probe.

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Miriam E. Ramos-Ceja, M. Oguri, S. Miyazaki, V. Ghirardini, I. Chiu, N. Okabe, A. Liu, T. Schrabback, D. Akino, Y. E. Bahar, E. Bulbul, N. Clerc, J. Comparat, S. Grandis, M. Klein, Y. -T. Lin, A. Merloni, I. Mitsuishi, H. Miyatake, S. More, K. Nandra, A. J. Nishizawa, N. Ota, F. Pacaud, T. H. Reiprich, J. S. Sanders. 2021-09-16. The eROSITA Final Equatorial-Depth Survey (eFEDS): A complete census of X-ray properties of Subaru Hyper Suprime-Cam weak lensing shear-selected clusters in the eFEDS footprint. https://doi.org/10.1051/0004-6361%2F202142214

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