{"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/a-first-detection-of-neutral-hydrogen","title":"A first detection of neutral hydrogen intensity mapping on Mpc scales at $z\\approx 0.32$ and $z\\approx 0.44$","arxiv_id":"2301.11943","date":"2023-01-27","proceeding":null,"authors":["Sourabh Paul","Zhaoting Chen","Mario G. Santos","Laura Wolz"],"abstract":"We report the detection of the cosmological power spectrum using the intensity mapping signal from 21-cm emission of neutral hydrogen (HI), derived from interferometric observations with the L-band receivers of the MeerKAT radio telescope. Intensity mapping is a promising technique to map the three-dimensional matter distribution of the Universe at radio frequencies and probe the underlying Cosmology. So far, detections have only been achieved through cross-correlations with galaxy surveys. Here we present independent measurements of the HI power spectrum at redshifts $0.32$ and $0.44$ with the foreground avoidance method. We utilize two distinct frameworks for mitigating systematics, where a conservative baseline flagging based approach achieves detections at $3.2\\sigma$ and $3.5\\sigma$, and a power spectrum based flagging method enhances the significance to $5.9\\sigma$ and $9.18\\sigma$, respectively. The information contained in the power spectrum measurements allows us to probe the parameters of the HI mass function and HI halo model. These results are a significant step towards precision cosmology with HI intensity mapping using the new generation of radio telescopes.","url_abs":"https://arxiv.org/abs/2301.11943v1","url_pdf":"https://arxiv.org/pdf/2301.11943v1.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":"a-first-detection-of-neutral-hydrogen","repo_url":"https://github.com/zhaotingchen/hiimtool","is_official":0,"mentioned_in_paper":0,"mentioned_in_github":1,"framework":"pytorch","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}