{"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/constraints-on-primordial-non-gaussianity-3","title":"Constraints on primordial non-Gaussianity from Quaia","arxiv_id":"2504.20992","date":"2025-04-29","proceeding":null,"authors":["Giulio Fabbian","David Alonso","Kate Storey-Fisher","Thomas Cornish"],"abstract":"We analyse the large-scale angular clustering of quasars in the \\gaia-\\unwise quasar catalog, \\quaia, and their cross-correlation with maps of the lensing convergence of the Cosmic Microwave Background (CMB), to constrain the level of primordial non-Gaussianity (PNG). Specifically, we target the scale-dependent bias that would be induced by PNG on biased tracers of the matter inhomogeneities on large scales. The \\quaia sample is particularly well suited for this analysis, given the large effective volume covered, and our ability to map out the main potential sources of systematic contamination and mitigate their impact. Using the universality relation to characterise the response of the quasar overdensity to PNG ($p_\\phi=1$), we report constraints on the local-type PNG parameter $f_{\\rm NL}$ of $f_{\\rm NL} =-20.5^{+19.0}_{-18.1}$ (68\\% C.L.) by combining the quasar auto-correlation and its cross-correlation with CMB lensing in two tomographic redshift bins (or $f_{\\rm NL} =-28.7^{+26.1}_{-24.6}$ if assuming a lower response for quasars, $p_\\phi=1.6$). The error on $f_{\\rm NL}$ can be further improved if the cross-correlation between the tomographic redshift bins is included. Using the CMB lensing cross-correlations alone, we find $f_{\\rm NL} =-13.8^{+26.7}_{-25.0}$ and $f_{\\rm NL} = -15.6^{+42.3}_{-34.8}$ for $p_\\phi=1$ and $p_\\phi=1.6$ respectively. These are the tightest constraints on $f_{\\rm NL}$ to date from angular clustering statistics and cross-correlations with CMB lensing.","url_abs":"https://arxiv.org/abs/2504.20992v1","url_pdf":"https://arxiv.org/pdf/2504.20992v1.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":"constraints-on-primordial-non-gaussianity-3","repo_url":"https://github.com/gfabbian/quaia-fnl","is_official":1,"mentioned_in_paper":1,"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}