Weak-Lensing Shear-Selected Galaxy Clusters in the Hyper Suprime-Cam Subaru Strategic Program and its Cosmological Applications

I-Non Chiu^1*, Kai-Feng Chen², Masamune Oguri³

¹Department of Physics, National Cheng Kung University, Tainan, Taiwan
²MIT Kavli Institute, Massachusetts Institute of Technology, Cambridge, USA
³Department of Physics, Chiba University, Chiba, Japan

* Presenter:I-Non Chiu, email:inchiu@phys.ncku.edu.tw

I will present cosmological constraints using the abundance of weak-lensing shear-selected galaxy clusters selected in the Hyper Suprime-Cam (HSC) Subaru Strategic Program. The clusters are selected on the mass maps constructed using the latest three-year (Y3) weak-lensing data with an area of ≈ 500 deg2, resulting in a sample size of 129 clusters with a high signal-to-noise ratio 𝜈 of 𝜈 ≥ 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. We obtain the fully marginalized constraint on \hat{S}_8 \equiv \sigma_8 \left(\Omega_{m}/0.3\right)^{0.25} = 0.835^{+0.041}_{-0.044} (corresponding to a ~5% constraint) in a flat LCDM model. This work realizes a cosmological probe utilizing weak-lensing shear-selected clusters and paves the way forward in the upcoming LSST era.

Keywords: cosmology, weak gravitational lensing, galaxy clusters