Galaxy–dark matter connection of photometric galaxies from the HSC-SSP Survey: galaxy–galaxy lensing and the halo model

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ABSTRACT We infer the connection between stellar mass of galaxies from Subaru Hyper Suprime-Cam (HSC) survey, and their dark matter halo masses in two bins of redshifts between [0.3, 0.8]. We use measurements of the weak lensing of background galaxies from Year-1 shape catalogue from the HSC survey. We bin lens galaxies in stellar mass with varying thresholds ranging from $8.6\le \log [M_*/(h^{-2}{M_\odot })]\le \, 11.2$ and use stringent cuts in the selection of source galaxies to measure the lensing signal. We model these measurements of the lensing signals together with the abundance of galaxies in the halo occupation distribution framework. We obtain constraints on the halo occupation parameters of central galaxies Mmin and σlog M along with parameters that describe the occupation of the satellite galaxies. The measurements of abundance and lensing individually constrain different degeneracy directions in Mmin− σlog M plane, thus breaking the degeneracy in these parameters. We demonstrate that the lensing measurements are best able to constrain average central halo masses, 〈Mcen〉. We compare our measurements to those obtained using the abundance and clustering of these galaxies. We find that the galaxy–dark matter connection does not vary significantly between redshift bins we explore in this study. Uncertainties in the photometric redshift of the lens galaxies need to be studied to understand the true underlying stellar mass–halo mass relation and evolution of galaxies.