Catalogs of optically-selected clusters and photometric luminous red galaxies from the Hyper Suprime-Cam Subaru Strategic Program final year dataset

TL;DR

This work delivers CAMIRA-based catalogs of optically-selected galaxy clusters and photometric luminous red galaxies from the HSC-SSP final-year dataset, covering about $1200$ deg$^2$ and extending to $z\sim 1.38$ for clusters and $z\sim 1.25$ for LRGs. It calibrates the cluster mass–richness relation using stacked weak lensing with a halo-model approach that accounts for mis-centering and the two-halo term, yielding robust mass inferences (e.g., $M_{200\mathrm{m}}\sim 10^{14} h^{-1} M_\odot$ at $\hat{N}_{\mathrm{mem}}=20$) and precise photometric redshifts ($\sigma_z\lesssim 0.01$ for clusters and $\sigma_z\lesssim 0.02$ for LRGs in key redshift ranges). The resulting catalogs—over 10,000 clusters and ~6 million LRGs—provide powerful resources for cosmology and galaxy evolution, including calibration of photometric redshifts and studies of central density profiles, with data publicly accessible via the project repository. The work also validates the optical catalogs through cross-matching with X-ray clusters, clarifying mis-centering effects and enabling improvements in cluster-based cosmological constraints. Overall, the paper advances large-scale structure studies by delivering high-fidelity, large-area cluster and LRG catalogs derived from the deepest existing optical imaging to date.

Abstract

We construct samples of optically-selected clusters and photometric luminous red galaxies (LRGs) from the Hyper Suprime-Cam Subaru Strategic Program final year dataset covering $\sim 1200$~deg$^2$. The cluster catalogs extend out to the redshift of $1.38$ and contain more than 10000 clusters with richness larger than $15$, where the richness is defined to be a membership probability weighted number of galaxies above the stellar masses of approximately $10^{10.2}M_\odot$. The total number of probable red cluster member galaxies in these clusters are more than $6\times 10^5$. Photometric redshifts of the clusters are shown to be precise with the scatter better than $\sim 0.01$ for a wide redshift range. We detect stacked weak lensing signals of clusters out to the redshift of $1$, and use them to update constraints on the mass-richness relation. Our catalog of about 6 million photometric LRGs extend out to the redshift of $1.25$, and have the scatter of the photometric redshift better than $\sim 0.02$ for the redshift range between $0.4$ and $1.0$.

Figures (11)

• Figure 1: Distribution of CAMIRA clusters on the sky. Filled red circles show positions of clusters in the Wide layer, while filled blue squares show positions of clusters in the Deep+UD layer. The bright star mask is applied. Alt text: The plot shows how CAMIRA clusters are distributed on the sky.
• Figure 2: Distribution of CAMIRA clusters in the redshift-richness plane. Contours indicates the density of clusters. Top and right panels show the histograms of the cluster redshift $z_{\mathrm{cl}}$ and the richness $\hat{N}_{\mathrm{mem}}$, respectively. Alt text: In the main plot, the x axis shows the redshift from 0.1 to 1.38, and the y axis shows the richness from 15 to 200. Points show how CAMIRA clusters are distributed in this plane.
• Figure 3: Upper: The comparison between cluster photometric redshifts $z_{\mathrm{cl}}$ and spectroscopic redshifts of BCGs $z_{\mathrm{BCG,spec}}$. Values of the bias $\delta_z$, the scatter $\sigma_z$, and the outlier fraction of the redshift residual $(z_{\mathrm{cl}}-z_{\mathrm{BCG,spec}})/(1+z_{\mathrm{BCG,spec}})$ that are derived with $4\sigma$ clipping are also shown. Lower: The bias $\delta_z$, the scatter $\sigma_z$ of the redshift residual as a function of redshift. Alt text: the x and y axes show the redshift from 0.1 to 1.38.
• Figure 4: Examples of $gri$-composite color images of low- ( left), mid- ( middle), and high-redshift ( right) CAMIRA clusters. The size of each image is $\sim 5\farcm5$. Alt text: concentrations of red galaxies are shown.
• Figure 5: Comparison between richness $\hat{N}_{\mathrm{mem}}$ and eRASS1 X-ray luminosity $L_X$ with the correction of $[E(z)]^{-2}$, where $E(z)$ the Hubble parameter normalized by the Hubble constant. Here the X-ray luminosity refers to the bolometric luminosity within $r_{500}$bulbul24. Clusters at $z<0.2$, $0.2\leq z<0.5$, and $0.5\leq z$ are shown by blue circles, magenta stars, and red crosses, respectively. Alt text: the x axis shows the richness from 15 to 200, and the y axis shows the X-ray luminosity from three times 10 to 42 to 10 to 46 erg per second.