Hyper Suprime-Cam Year 3 results: Cosmology from galaxy clustering and weak lensing with HSC and SDSS using the minimal bias model

Abstract

We present cosmological parameter constraints from a blind joint analysis of three two-point correlation functions measured from the Year 3 Hyper Suprime-Cam (HSC-Y3) imaging data, covering about 416 deg2, and the SDSS DR11 spectroscopic galaxies spanning the redshift range [0.15, 0.70]. We subdivide the SDSS galaxies into three luminosity-cut, and therefore nearly volume-limited samples separated in redshift, each of which acts as a large-scale structure tracer characterized by the measurement of the projected correlation function, wp(R). We also use the measurements of the galaxy-galaxy weak-lensing signal Δς(R) for each of these SDSS samples which act as lenses for a secure sample of source galaxies selected from the HSC-Y3 shape catalog based on their photometric redshifts. We combine these measurements with the cosmic shear correlation functions, ζ± measured for our HSC source sample. We model these observables with the minimal bias model of the galaxy clustering observables in the context of a flat ΛCDM cosmology. We use conservative scale cuts, R>12 and 8h-1 Mpc for Δς and wp, respectively, where the minimal bias model is valid, in addition to conservative prior on the residual bias in the mean redshift of the HSC photometric source galaxies. We present various validation tests of our model as well as analysis methods. Our baseline analysis yields S8=0.775-0.038+0.043 (68% C.I.) for the ΛCDM model, after marginalizing over uncertainties in other parameters. Our value of S8 is consistent with that from the Planck 2018 data, but the credible interval of our result is still relatively large. We show that various internal consistency tests based on different splits of the data are passed. Our results are statistically consistent with those of a companion paper, which extends this analysis to smaller scales with an emulator-based halo model, using Δς(R) and wp(R) down to R>3 and 2h-1 Mpc, respectively. © 2023 American Physical Society.