Cosmological constraints from density-split clustering in the BOSS CMASS galaxy sample

Journal Article · 25 April 2024 · Monthly Notices of the Royal Astronomical Society

DOI: https://doi.org/10.1093/mnras/stae1118 · OSTI ID:2403622

Paillas, Enrique  ^[1]; Cuesta-Lazaro, Carolina  ^[2]; Percival, Will J.  ^[3]; Nadathur, Seshadri  ^[4]; Cai, Yan-Chuan  ^[5]; Yuan, Sihan  ^[6]; Beutler, Florian  ^[5]; de Mattia, Arnaud  ^[7]; Eisenstein, Daniel J.  ^[8]; Forero-Sanchez, Daniel  ^[9]; Padilla, Nelson  ^[10]; Pinon, Mathilde  ^[7]; Ruhlmann-Kleider, Vanina  ^[7]; Sánchez, Ariel G.  ^[11]; Valogiannis, Georgios  ^[12]; Zarrouk, Pauline  ^[13]

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1. Univ. of Waterloo, ON (Canada); SLAC
2. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); NSF AI Institute for Artificial Intelligence and Fundamental Interactions (IAIFI), Cambridge, MA (United States); Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
3. Univ. of Waterloo, ON (Canada); Perimeter Inst. for Theoretical Physics, Waterloo, ON (Canada)
4. Univ. of Portsmouth (United Kingdom)
5. Univ. of Edinburgh, Scotland (United Kingdom)
6. Stanford Univ., CA (United States). Kavli Institute for Particle Astrophysics & Cosmology; SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
7. CEA, IRFU, Gif-sur-Yvette (France); Univ. Paris-Saclay, Gif-sur-Yvette (France)
8. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States)
9. Ecole Polytechnique Federale Lausanne (EPFL), Versoix (Switzerland)
10. National Scientific and Technical Research Council (CONICET), Cordoba (Argentina); Univ. Nacional de Cordoba (Argentina)
11. Max Planck Inst. fuer Extraterrestrische Physik, Garching (Germany)
12. Harvard Univ., Cambridge, MA (United States); Univ. of Chicago, IL (United States)
13. Sorbonne Univ., Paris (France); University Paris-Diderot (France); Laboratory Nuclear Physics and High Energies (LPNHE), Paris (France); Centre National de la Recherche Scientifique (CNRS), Paris (France); Univ. Paris Cité (France)

We present a clustering analysis of the BOSS DR12 CMASS galaxy sample, combining measurements of the galaxy two-point correlation function and density-split clustering down to a scale of $$1 \, h^{-1}\, \text{Mpc}$$. Our theoretical framework is based on emulators trained on high-fidelity mock galaxy catalogues that forward model the cosmological dependence of the clustering statistics within an extended-ΛCDM framework, including redshift-space and Alcock–Paczynski distortions. Our base-ΛCDM analysis finds ω_cdm = 0.1201 ± 0.0022, σ₈ = 0.792 ± 0.034, and n_s = 0.970 ± 0.018, corresponding to fσ₈ = 0.462 ± 0.020 at z ≈ 0.525, which is in agreement with Planck 2018 predictions and various clustering studies in the literature. We test single-parameter extensions to base-ΛCDM, varying the running of the spectral index, the dark energy equation of state, and the density of mass-less relic neutrinos, finding no compelling evidence for deviations from the base model. We model the galaxy–halo connection using a halo occupation distribution framework, finding signatures of environment-based assembly bias in the data. We validate our pipeline against mock catalogues that match the clustering and selection properties of CMASS, showing that we can recover unbiased cosmological constraints even with a volume 84 times larger than the one used in this study.

• Research Organization: SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF); Natural Sciences and Engineering Research Council of Canada (NSERC); Science & Technology Facilities Council (STFC)
• Grant/Contract Number: AC02-76SF00515; AC05-00OR22725; AC02-05CH11231; SC0013718
• OSTI ID: 2403622
• Journal Information: Monthly Notices of the Royal Astronomical Society, Journal Name: Monthly Notices of the Royal Astronomical Society Journal Issue: 1 Vol. 531; ISSN 0035-8711
• Publisher: Oxford University PressCopyright Statement
• Country of Publication: United States
• Language: English