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arXiv · 2103.15016

Hundreds of weak lensing shear-selected clusters from the Hyper Suprime-Cam Subaru Strategic Program S19A data

Abstract

We use the Hyper Suprime-Cam Subaru Strategic Program S19A shape catalog to construct weak lensing shear-selected cluster samples. From aperture mass maps covering $\sim 510$~deg$^2$ created using a truncated Gaussian filter, we construct a catalog of 187 shear-selected clusters that correspond to mass map peaks with the signal-to-noise ratio larger than 4.7. Most of the shear-selected clusters have counterparts in optically-selected clusters, from which we estimate the purity of the catalog to be higher than 95\%. The sample can be expanded to 418 shear-selected clusters with the same signal-to-noise ratio cut by optimizing the shape of the filter function and by combining weak lensing mass maps created with several different background galaxy selections. We argue that dilution and obscuration effects of cluster member galaxies can be mitigated by using background source galaxy samples and adopting the filter function with its inner boundary larger than about $2'$. The large samples of shear-selected clusters that are selected without relying on any baryonic tracer are useful for detailed studies of cluster astrophysics and cosmology.

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Masamune Oguri, Satoshi Miyazaki, Xiangchong Li, Wentao Luo, Ikuyuki Mitsuishi, Hironao Miyatake, Surhud More, Atsushi J. Nishizawa, Nobuhiro Okabe, Naomi Ota, Andrés A. Plazas Malagón, Yousuke Utsumi. 2021-07-09. Hundreds of weak lensing shear-selected clusters from the Hyper Suprime-Cam Subaru Strategic Program S19A data. https://doi.org/10.1093/pasj%2Fpsab047

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