{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/galaxy-clustering-in-the-desi-legacy-survey","title":"Galaxy clustering in the DESI Legacy Survey and its imprint on the CMB","arxiv_id":"2010.00466","date":"2020-10-01","proceeding":null,"authors":["Qianjun Hang","Shadab Alam","John A. Peacock","Yan-Chuan Cai"],"abstract":"We use data from the DESI Legacy Survey imaging to probe the galaxy density field in tomographic slices covering the redshift range $0<z<0.8$. After careful consideration of completeness corrections and galactic cuts, we obtain a sample of $4.9\\times 10^7$ galaxies covering 17 739 deg$^2$. We derive photometric redshifts with precision $\\sigma_z/(1+z)=0.012 - 0.015$, and compare with alternative estimates. Cross-correlation of the tomographic galaxy maps with Planck maps of CMB temperature and lensing convergence probe the growth of structure since $z=0.8$. The signals are compared with a fiducial Planck $\\Lambda$CDM model, and require an overall scaling in amplitude of $A_\\kappa=0.901\\pm 0.026$ for the lensing cross-correlation and $A_{\\rm ISW} = 0.984 \\pm 0.349$ for the temperature cross-correlation, interpreted as the Integrated Sachs-Wolfe effect. The ISW amplitude is consistent with the fiducial $\\Lambda$CDM prediction, but lies significantly below the prediction of the AvERA model of R\\'acz et al. (2017), which has been proposed as an alternative explanation for cosmic acceleration. Within $\\Lambda$CDM, our low amplitude for the lensing cross-correlation requires a reduction either in fluctuation normalization or in matter density compared to the Planck results, so that $\\Omega_m^{0.78}\\sigma_8=0.297\\pm 0.009$. In combination with the total amplitude of CMB lensing, this favours a shift mainly in density: $\\Omega_m=0.274\\pm0.024$. We discuss the consistency of this figure with alternative evidence. A conservative compromise between lensing and primary CMB constraints would require $\\Omega_m=0.296\\pm0.006$, where the 95% confidence regions of both probes overlap.","url_abs":"https://arxiv.org/abs/2010.00466v2","url_pdf":"https://arxiv.org/pdf/2010.00466v2.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"galaxy-clustering-in-the-desi-legacy-survey","repo_url":"https://gitlab.com/qianjunhang/desi-legacy-survey-cross-correlations","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":1,"framework":"none","reach":null},{"paper_slug":"galaxy-clustering-in-the-desi-legacy-survey","repo_url":"https://gitlab.com/qianjunhang/desi-legacy-survey-superstructure-stacking","is_official":0,"mentioned_in_paper":0,"mentioned_in_github":1,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"syntology_url":null,"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}