Weak-Lensing Shear-Selected Galaxy Clusters from the Hyper Suprime-Cam Subaru Strategic Program: II. Cosmological Constraints from the Cluster Abundance

Abstract

We present cosmological constraints using the abundance of weak-lensing shear-selected galaxy clusters in the Hyper Suprime-Cam (HSC) Subaru Strategic Program. The clusters are selected on the mass maps constructed using the three-year (Y3) weak-lensing data with an area of $\approx 500$deg${}^2$, resulting in a sample size of $129$ clusters with high signal-to-noise ratios $\hat{I}½$ of $\hat{I}½\ge 4.7$. Owing to the deep, wide-field, and uniform imaging of the HSC survey, this is by far the largest sample of shear-selected clusters, in which the selection solely depends on gravity and is free from any assumptions about the dynamical state. Informed by the optical counterparts, the shear-selected clusters span a redshift range of $z\lesssim 0.7$ with a median of $z\approx 0.3$. The lensing sources are securely selected at $z\gtrsim 0.7$ with a median of $z\approx 1.3$, leading to nearly zero cluster member contamination. We carefully account for (1) the bias in the photometric redshift of sources, (2) the bias and scatter in the weak-lensing mass using a simulation-based calibration, and (3) the measurement uncertainty that is directly estimated on the mass maps using an injection-based method developed in a companion paper (Chen et al. submitted). In a blind analysis, the fully marginalized posteriors of the cosmological parameters are obtained as $\hat{I}{\text{c◯}}_{\mathrm{m}}=0.50_{-0.24}^{+0.28}$, $\ddot{I}{ƒ}_8=0.685_{-0.088}^{+0.161}$, ${\hat{S}}_8\equiv \ddot{I}{ƒ}_8{\left(\hat{I}{\text{c◯}}_{\mathrm{m}}/0.3\right)}^{0.25}=0.835_{-0.044}^{+0.041}$, and $\ddot{I}{ƒ}_8{\left(\hat{I}{\text{c◯}}_{\mathrm{m}}/0.3\right)}^{0.5}=0.993_{-0.126}^{+0.084}$ in a flat $\hat{I}›$CDM model. We compare our cosmological constraints with other studies, including those based on cluster abundances, galaxy-galaxy lensing and clustering, and Cosmic Microwave Background observed by $Planck$, and find good agreement at levels of $\lesssim 2\ddot{I}ƒ$. [abridged]

Accepted for publication in the Open Journal of Astrophysics. Main results are Figures 11 and 12. The cluster catalog and the cosmological chain are accessible at https://github.com/inonchiu/hsc_shear_selected_clusters