{"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/the-epoch-of-reionization-21-cm-bispectrum-i","title":"The Epoch of Reionization 21-cm Bispectrum: The impact of light-cone effects and detectability","arxiv_id":"2107.02668","date":"2021-07-06","proceeding":null,"authors":["Rajesh Mondal","Garrelt Mellema","Abinash Kumar Shaw","Mohd Kamran","Suman Majumdar"],"abstract":"We study the spherically averaged bispectrum of the 21-cm signal from the Epoch of Reionization (EoR). This metric provides a quantitative measurement of the level of non-Gaussianity of the signal which is expected to be high. We focus on the impact of the light-cone effect on the bispectrum and its detectability with the future SKA-Low telescope. Our investigation is based on a single reionization light-cone model and an ensemble of 50 realisations of the 21-cm signal to estimate the cosmic variance errors. We calculate the bispectrum with a new, optimised direct estimation method, DviSukta which calculates the bispectrum for all possible unique triangles. We find that the light-cone effect becomes important on scales $k_1 \\lesssim 0.1\\,{\\rm Mpc}^{-1}$ where for most triangle shapes the cosmic variance errors dominate. Only for the squeezed limit triangles, the impact of the light-cone effect exceeds the cosmic variance. Combining the effects of system noise and cosmic variance we find that $\\sim 3\\sigma$ detection of the bispectrum is possible for all unique triangle shapes around a scale of $k_1 \\sim 0.2\\,{\\rm Mpc}^{-1}$, and cosmic variance errors dominate above and noise errors below this length scale. Only the squeezed limit triangles are able to achieve a more than $5\\sigma$ significance over a wide range of scales, $k_1 \\lesssim 0.8\\,{\\rm Mpc}^{-1}$. Our results suggest that among all the possible triangle combinations for the bispectrum, the squeezed limit one will be the most measurable and hence useful.","url_abs":"https://arxiv.org/abs/2107.02668v2","url_pdf":"https://arxiv.org/pdf/2107.02668v2.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":"the-epoch-of-reionization-21-cm-bispectrum-i","repo_url":"https://github.com/rajeshmondal18/DviSukta","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}