Clustering properties and peculiar velocities of halos in large-scale structure carry a wealth of cosmological information over a wide range of scales from linear to nonlinear scales. We use halo catalogs in a suite of high-resolution $N$-body simulations to construct mock catalogs of galaxies that resemble the Sloan Digital Sky Survey (SDSS)-like luminous early type galaxies at three redshift bins in the range $0.15\le z\le 0.7$. To do this, we include ten nuisance parameters to model variations in halo-galaxy connections for each redshift bin, the halo occupation distribution, and the spatial and velocity distributions of galaxies in the host halos. We evaluate the Fisher information matrix for the redshift-space power spectrum of SDSS-like galaxies using different sets of the mock catalogs that are generated from changes in each of model parameters, cosmological parameters (${\sigma }_8$ and ${\mathrm{\Omega }}_{\mathrm{m}}$), the halo-galaxy connection parameters, and the cosmological distances ($D_{\mathrm{A}}$ and $H$ parameters at each redshift bin) for modeling an apparent geometrical distortion of the redshift-space power spectrum (the Alcock-Paczynski effect). We show that combining the monopole and quadrupole power spectra of galaxies allows for precise estimations of the cosmological parameters and the cosmological distances, even after marginalization over the halo-galaxy parameters, by lifting the parameter degeneracies that are otherwise inevitable if either of the two spectra alone is used. When including the galaxy power spectrum information up to $k=0.3h{\mathrm{Mpc}}^{-1}$, we find about factor of 6 gain in the cosmological information content of (${\sigma }_8$, ${\mathrm{\Omega }}_{\mathrm{m}}$, $D_{\mathrm{A}}$’s, and $H$’s) compared to $k=0.2h{\mathrm{Mpc}}^{-1}$. We also discuss the use of redshift-space galaxy power spectrum for a model-independent measurement of redshift-space distortion strength and a possible impact of the assembly bias on the cosmological parameters.

• Received 24 July 2019

DOI:https://doi.org/10.1103/PhysRevD.101.023510