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arXiv · 2111.11657

Construct the emission line galaxy-host halo connection through auto and cross correlations

Hongyu Gao·Y. P. Jing·Yun Zheng·Kun Xu
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Abstract

We investigate the [O\,II] emission line galaxy (ELG)-host halo connection via auto and cross correlations, and propose a concise and effective method to populate ELGs in dark matter halos without assuming a parameterized halo occupation distribution (HOD) model. Using the observational data from VIMOS Public Extragalactic Redshift Survey (VIPERS), we measure the auto and cross correlation functions between ELGs selected by [O\,II] luminosity and normal galaxies selected by stellar mass. Combining the stellar-halo mass relation (SHMR) derived for the normal galaxies and the fraction of ELGs observed in the normal galaxy population, we demonstrate that we can establish an accurate ELG-halo connection. With the ELG-halo connection, we can accurately reproduce the auto and cross correlation functions of ELGs and normal galaxies both in real-space and in redshift-space, once the satellite fraction is properly reduced. Our method provides a novel strategy to generate ELG mock catalogs for ongoing and upcoming galaxy redshift surveys. We also provide a simple description for the HOD of ELGs.

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Hongyu Gao, Y. P. Jing, Yun Zheng, Kun Xu. 2021-11-23. Construct the emission line galaxy-host halo connection through auto and cross correlations. https://doi.org/10.3847/1538-4357%2Fac501b

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