In ongoing and future cosmological surveys, such as DESI, PFS, Euclid, CSST, and WFIRST, ELGs are a critically major tracer to explore the acceleration of the cosmic expansion and to test modified gravity theories. To achieve the high-precision observations aimed by the surveys on the Hubble parameter, cosmic growth rate and neutrino mass etc, one needs to have an accurate understanding of...
The Photometric objects Around Cosmic webs (PAC) approach developed in \cite{2022ApJ...925...31X} has the advantage of making full use of the spectroscopic and deeper photometric surveys. With the merits of PAC, we can accurately measure quasars-galaxy cross-correlations at small scale down to $0.1\,h^{-1}{\rm{Mpc}}$ and at different stellar mass bins. We calculate the excess surface density...
This work consists of two parts. The first is the study of the galaxy population in the SDSS galaxy groups with DESI imaging data. The second is the study on how to measure galaxy abundance and clustering at high redshift from incomplete spectroscopic data.
In the first part, we use the most recent data release (DR9) of the DESI legacy imaging survey and SDSS galaxy groups to measure the...
In the framework of the standard cosmological model, dark matter halos grow by hierarchical clumping. The spatial distribution of satellite galaxies is closely related to the nature of the halo and its accretion history. Firstly, using SDSS and Millennium simulations we study the spatial distribution of satellites in galaxy clusters. We find that the distribution of satellite galaxies is...
Motivated by previous findings that the magnitude gap between certain satellite galaxies and the central galaxy can be used to improve the estimation of halo mass, we carry out a systematic study of the information content of different member galaxies in the modeling of the host halo mass using a machine-learning approach. We employ data from the hydrodynamical simulation IllustrisTNG and...
In this investigation, we leverage the combination of DESI legacy imaging surveys DR9, survey vilification (sv3), and year 1 (Y1) spectroscopic redshift data to estimate the conditional luminosity and stellar mass functions (CLFs & CSMFs) of galaxies across various halo mass bins and redshift ranges, with the help of a realistic DESI mock galaxy redshift survey (MGRS) generated from a...
