The Aemulus Project. VI. Emulation of Beyond-standard Galaxy Clustering Statistics to Improve Cosmological Constraints

Journal Article · 25 January 2024 · The Astrophysical Journal

DOI: https://doi.org/10.3847/1538-4357/ad0ce8 · OSTI ID:2282912

Storey-Fisher, Kate ; Tinker, Jeremy L. ; Zhai, Zhongxu ; DeRose, Joseph ; Wechsler, Risa H. ; Banerjee, Arka

Abstract There is untapped cosmological information in galaxy redshift surveys in the nonlinear regime. In this work, we use the Aemulus suite of cosmological N -body simulations to construct Gaussian process emulators of galaxy clustering statistics at small scales (0.1–50 h ⁻¹ Mpc) in order to constrain cosmological and galaxy bias parameters. In addition to standard statistics—the projected correlation function w _p ( r _p ), the redshift-space monopole of the correlation function ξ ₀ ( s ), and the quadrupole ξ ₂ ( s )—we emulate statistics that include information about the local environment, namely the underdensity probability function P _U ( s ) and the density-marked correlation function M ( s ). This extends the model of Aemulus III for redshift-space distortions by including new statistics sensitive to galaxy assembly bias. In recovery tests, we find that the beyond-standard statistics significantly increase the constraining power on cosmological parameters of interest: including P _U ( s ) and M ( s ) improves the precision of our constraints on Ω _m by 27%, σ ₈ by 19%, and the growth of structure parameter, f σ ₈ , by 12% compared to standard statistics. We additionally find that scales below ∼6 h ⁻¹ Mpc contain as much information as larger scales. The density-sensitive statistics also contribute to constraining halo occupation distribution parameters and a flexible environment-dependent assembly bias model, which is important for extracting the small-scale cosmological information as well as understanding the galaxy–halo connection. This analysis demonstrates the potential of emulating beyond-standard clustering statistics at small scales to constrain the growth of structure as a test of cosmic acceleration.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
• Sponsoring Organization: National Aeronautics and Space Administration (NASA); National Science Foundation (NSF); USDOE; USDOE Office of Science (SC); USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF); USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: AC02-05CH11231; AC02-76SF00515
• OSTI ID: 2282912
• Journal Information: The Astrophysical Journal, Journal Name: The Astrophysical Journal Journal Issue: 2 Vol. 961; ISSN 0004-637X
• Publisher: American Astronomical SocietyCopyright Statement
• Country of Publication: United States
• Language: English