The Subaru HSC Galaxy Clustering with Photometric Redshift I: Dark Halo Masses Versus Baryonic Properties of Galaxies at 0.3<z<1.4

TL;DR

This study analyzes galaxy clustering and dark halo properties at redshifts 0.3 to 1.4 using wide-field Subaru data, revealing relationships between baryonic and dark matter properties and identifying a universal pivot halo mass.

Contribution

It provides the first detailed clustering and halo occupation analysis for a large galaxy sample at 0.3<z<1.4, connecting baryonic properties with dark halo characteristics.

Findings

The satellite galaxy fraction remains nearly constant at ~20% for less-massive galaxies at z<1.

The stellar-to-halo mass ratios align with empirical models, with small excesses at the massive end.

A universal pivot halo mass of ~10^{12}h^{-1}M_{} is consistent up to z~5.

Abstract

We present the clustering properties of low-$z$ $(z\leq1.4)$ galaxies selected by the Hyper Suprime-Cam Subaru Strategic Program Wide layer over $145$ deg$^{2}$. The wide-field and multi-wavelength observation yields $5,064,770$ galaxies at $0.3\leq z\leq1.4$ with photometric redshifts and physical properties. This enables the accurate measurement of angular correlation functions and subsequent halo occupation distribution (HOD) analysis allows the connection between baryonic properties and dark halo properties. The fraction of less-massive satellite galaxies at $z\lesssim1$ is found to be almost constant at $\sim20\%$, but it gradually decreases beyond $M_{\star} \sim 10^{10.4}h^{-2}M_{\odot}$. However, the abundance of satellite galaxies at $z>1$ is quite small even for less-massive galaxies due to the rarity of massive centrals at high-$z$. This decreasing trend is connected to the small satellite fraction of Lyman break galaxies at $z>3$. The stellar-to-halo mass ratios at $0.3\leq z\leq1.4$ are almost consistent with the predictions obtained using the latest empirical model; however, we identify small excesses from the theoretical model at the massive end. The pivot halo mass is found to be unchanged at $10^{11.9-12.1}h^{-1}M_{\odot}$ at $0.3\leq z\leq1.4$, and we systematically show that $10^{12}h^{-1}M_{\odot}$ is a universal pivot halo mass up to $z\sim5$ that is derived using only the clustering/HOD analyses. Nevertheless, halo masses with peaked instantaneous baryon conversion efficiencies are much smaller than the pivot halo mass regardless of a redshift, and the most efficient stellar-mass assembly is thought to be in progress in $10^{11.0-11.5}h^{-1}M_{\odot}$ dark haloes.