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arXiv · 1802.08692

X-ray properties of high-richness CAMIRA clusters in the Hyper Suprime-Cam Subaru Strategic Program field

Naomi Ota·Ikuyuki Mitsuishi·Yasunori Babazaki·Hiroki Akamatsu·Yuto Ichinohe·Shutaro Ueda·Nobuhiro Okabe·Masamune Oguri·Ryuichi Fujimoto·Takashi Hamana·Keita Miyaoka·Satoshi Miyazaki·Hanae Otani·Keigo Tanaka·Ayumi Tsuji·Atsushi Yoshida
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Abstract

We present the first results of a pilot X-ray study of 37 rich galaxy clusters at $0.1<z<1.1$ in the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) field. Diffuse X-ray emissions from these clusters were serendipitously detected in the XMM-Newton fields of view. We systematically analyze X-ray images of 37 clusters and emission spectra of a subsample of 17 clusters with high photon statistics by using the XMM-Newton archive data. The frequency distribution of the offset between the X-ray centroid or peak and the position of the brightest cluster galaxy was derived for the optical cluster sample. The fraction of relaxed clusters estimated from the X-ray peak offsets in 17 clusters is $29\pm11(\pm13)$\%, which is smaller than that of the X-ray cluster samples such as HIFLUGCS. Since the optical cluster search is immune to the physical state of X-ray-emitting gas, it is likely to cover a larger range of the cluster morphology. We also derived the luminosity-temperature relation and found that the slope is marginally shallower than those of X-ray-selected samples and consistent with the self-similar model prediction of 2. Accordingly, our results show that the X-ray properties of the optical clusters are marginally different from those observed in the X-ray samples. The implication of the results and future prospects are briefly discussed.

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Naomi Ota, Ikuyuki Mitsuishi, Yasunori Babazaki, Hiroki Akamatsu, Yuto Ichinohe, Shutaro Ueda, Nobuhiro Okabe, Masamune Oguri, Ryuichi Fujimoto, Takashi Hamana, Keita Miyaoka, Satoshi Miyazaki, Hanae Otani, Keigo Tanaka, Ayumi Tsuji, Atsushi Yoshida. 2019-10-08. X-ray properties of high-richness CAMIRA clusters in the Hyper Suprime-Cam Subaru Strategic Program field. https://doi.org/10.1093/pasj%2Fpsz118

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