Kavli Affiliate: Chiaki Hikage
| Summary:
We present high-fidelity cosmology results from a blinded joint analysis of galaxy-galaxy weak lensing ($Δ!Σ$) and projected galaxy clustering ($w_rm p$) measured from the Hyper Suprime-Cam Year-1 (HSC-Y1) data and spectroscopic Sloan Digital Sky Survey (SDSS) galaxy catalogs in the redshift range $0.15<z<0.7$. We define luminosity-limited samples of SDSS galaxies to serve as the tracers of $w_rm p$ in three spectroscopic redshift bins, and as the lens samples for $Δ!Σ$. For the $Δ!Σ$ measurements, we select a single sample of 4 million source galaxies over 140 deg$^2$ from HSC-Y1 with photometric redshifts (photo-$z$) greater than 0.75, enabling a better handle of photo-$z$ errors by comparing the $Δ!Σ$ amplitudes for the three lens redshift bins. For cosmological parameter inference, we use an input galaxy-halo connection model built on the tt Dark Emulator package with a halo occupation distribution that includes nuisance parameters to marginalize over modeling uncertainties. We model the $Δ!Σ$ and $w_rm p$ measurements on scales from $Rsimeq 3$ and $2,h^-1rm Mpc$, respectively, up to $30,h^-1rm Mpc$ assuming a flat $Λ$CDM cosmology. With various tests using mock catalogs described in Miyatake et al. (2021), we show that any bias in the clustering amplitude $S_8equiv σ_8(Ω_rm m/0.3)^0.5$ due to uncertainties in the galaxy-halo connection is less than $sim50$% of the statistical uncertainty of $S_8$, it unless the assembly bias effect is unexpectedly large. Our best-fit models have $S_8=0.795^+0.049_-0.042$ (mode and 68% credible interval) for the flat $Λ$CDM model; we find tighter constraints on the quantity $S_8(α=0.17)equivσ_8(Ω_rm m/0.3)^0.17 =0.745^+0.039_-0.031$. (abriged)
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