{"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/prospects-of-a-statistical-detection-of-the","title":"Prospects of a statistical detection of the 21-cm forest and its potential to constrain the thermal state of the neutral IGM during reionization","arxiv_id":"2412.06879","date":"2024-12-09","proceeding":null,"authors":["Tomáš Šoltinský","Girish Kulkarni","Shriharsh P. Tendulkar","James S. Bolton"],"abstract":"The 21-cm forest signal is a promising probe of the Epoch of Reionization complementary to other 21-cm line observables and Ly$\\alpha$ forest signal. Prospects of detecting it have significantly improved in the last decade thanks to the discovery of more than 30 radio-loud quasars at these redshifts, upgrades to telescope facilities, and the notion that neutral hydrogen islands persist down to $z\\lesssim 5.5$. We forward-model the 21-cm forest signal using semi-numerical simulations and incorporate various instrumental features to explore the potential of detecting the 21-cm forest at $z=6$, both directly and statistically, with the currently available (uGMRT) and forthcoming (SKA1-low) observatories. We show that it is possible to detect the 1D power spectrum of the 21-cm forest spectrum, especially at large scales of $k\\lesssim8.5\\,\\rm MHz^{-1}$ with the $500\\,\\rm hr$ of the uGMRT time and $k\\lesssim32.4\\,\\rm MHz^{-1}$ with the SKA1-low over $50\\,\\rm hr$ if the intergalactic medium (IGM) is $25\\%$ neutral and these neutral hydrogen regions have a spin temperature of $\\lesssim30\\,\\rm K$. On the other hand, we infer that a null-detection of the signal with such observations of 10 radio-loud sources at $z\\approx6$ can be translated into constraints on the thermal and ionization state of the IGM which are tighter than the currently available measurements. Moreover, a null-detection of the 1D 21-cm forest power spectrum with only $50\\,\\rm hr$ of the uGMRT observations of 10 radio-loud sources can already be competitive with the Ly$\\alpha$ forest and 21-cm tomographic observations in disfavouring models of significantly neutral and cold IGM at $z=6$.","url_abs":"https://arxiv.org/abs/2412.06879v2","url_pdf":"https://arxiv.org/pdf/2412.06879v2.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":"prospects-of-a-statistical-detection-of-the","repo_url":"https://github.com/tomassoltinsky/21cm-forest_1DPS","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":0,"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}