{"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/towards-simulating-and-quantifying-the-light","title":"Towards simulating and quantifying the light-cone EoR 21-cm signal","arxiv_id":"1706.09449","date":"2017-06-28","proceeding":null,"authors":["Rajesh Mondal","Somnath Bharadwaj","Kanan K. Datta"],"abstract":"The light-cone (LC) effect causes the Epoch of Reionization (EoR) 21-cm signal $T_{\\rm b} (\\hat{\\bf{n}}, \\nu)$ to evolve significantly along the line of sight (LoS) direction $\\nu$. In the first part of this paper, we present a method to properly incorporate the LC effect in simulations of the EoR 21-cm signal that include peculiar velocities. Subsequently, we discuss how to quantify the second order statistics of the EoR 21-cm signal in the presence of the LC effect. We demonstrate that the 3D power spectrum $P({\\bf{k}})$ fails to quantify the entire information because it assumes the signal to be ergodic and periodic, whereas the LC effect breaks these conditions along the LoS. Considering a LC simulation centered at redshift $8$ where the mean neutral fraction drops from $0.65$ to $0.35$ across the box, we find that $P({\\bf{k}})$ misses out $\\sim 40 \\%$ of the information at the two ends of the $17.41 \\, {\\rm MHz}$ simulation bandwidth. The multi-frequency angular power spectrum (MAPS) ${\\mathcal C}_{\\ell}(\\nu_1,\\nu_2)$ quantifies the statistical properties of $T_{\\rm b} (\\hat{\\bf{n}}, \\nu)$ without assuming the signal to be ergodic and periodic along the LoS. We expect this to quantify the entire statistical information of the EoR 21-cm signal. We apply MAPS to our LC simulation and present preliminary results for the EoR 21-cm signal.","url_abs":"https://arxiv.org/abs/1706.09449v3","url_pdf":"https://arxiv.org/pdf/1706.09449v3.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":"towards-simulating-and-quantifying-the-light","repo_url":"https://github.com/rajeshmondal18/MAPS","is_official":1,"mentioned_in_paper":0,"mentioned_in_github":1,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}