Clustering of quasars in the First Year of the SDSS-IV eBOSS survey: Interpretation and halo occupation distribution

TL;DR

This study analyzes the clustering of approximately 70,000 quasars from the SDSS-IV eBOSS survey, modeling their halo occupation and bias evolution to improve understanding of quasar environments and cosmological implications.

Contribution

It provides the first clustering analysis of eBOSS quasars, develops high-fidelity mock catalogues, and models quasar host halo properties using a modified Halo Abundance Matching approach.

Findings

Quasars are hosted by halos with masses around 10^12.7 solar masses.

Quasar bias increases from 1.54 at z=1.06 to 3.15 at z=1.98.

Current data cannot distinguish models with different satellite fractions.

Abstract

In current and future surveys, quasars play a key role. The new data will extend our knowledge of the Universe as it will be used to better constrain the cosmological model at redshift $z>1$ via baryon acoustic oscillation and redshift space distortion measurements. Here, we present the first clustering study of quasars observed by the extended Baryon Oscillation Spectroscopic Survey. We measure the clustering of $\sim 70,000$ quasars located in the redshift range $0.9<z<2.2$ that cover 1,168 deg$^2$. We model the clustering and produce high-fidelity quasar mock catalogues based on the BigMultiDark Planck simulation. Thus, we use a modified (Sub)Halo Abundance Matching model to account for the specificities of the halo population hosting quasars. We find that quasars are hosted by halos with masses $\sim10^{12.7}M_\odot$ and their bias evolves from 1.54 ($z=1.06$) to 3.15 ($z=1.98$). Using the current eBOSS data, we cannot distinguish between models with different fractions of satellites. The high-fidelity mock light-cones, including properties of halos hosting quasars, are made publicly available.