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arXiv · 1712.00029

The HectoMAP Cluster Survey - II. X-ray Clusters

Jubee Sohn·Gayoung Chon·Hans Böhringer·Margaret J. Geller·Antonaldo Diaferio·Ho Seong Hwang·Yousuke Utsumi·Kenneth J. Rines
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Abstract

We apply a friends-of-friends algorithm to the HectoMAP redshift survey and cross-identify associated X-ray emission in the ROSAT All-Sky Survey data (RASS). The resulting flux limited catalog of X-ray cluster survey is complete to a limiting flux of $\sim3 \times10^{-13}$ erg s$^{-1}$ cm$^{-2}$ and includes 15 clusters (7 newly discovered) with redshift $z \leq 0.4$. HectoMAP is a dense survey ($\sim1200$ galaxies deg$^{-2}$) that provides $\sim50$ members (median) in each X-ray cluster. We provide redshifts for the 1036 cluster members. Subaru/Hyper Suprime-Cam imaging covers three of the X-ray systems and confirms that they are impressive clusters. The HectoMAP X-ray clusters have an $L_{X} - {\sigma}_{cl}$ scaling relation similar to that of known massive X-ray clusters. The HectoMAP X-ray cluster sample predicts $\sim 12000 \pm3000$ detectable X-ray clusters in the RASS to the limiting flux, comparable with previous estimates.

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Jubee Sohn, Gayoung Chon, Hans Böhringer, Margaret J. Geller, Antonaldo Diaferio, Ho Seong Hwang, Yousuke Utsumi, Kenneth J. Rines. 2017-11-30. The HectoMAP Cluster Survey - II. X-ray Clusters. https://doi.org/10.3847/1538-4357/aaac7a

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