{"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/heating-of-the-intergalactic-medium-by","title":"Heating of the Intergalactic Medium by Hydrogen Reionization","arxiv_id":"1807.09282","date":"2018-07-24","proceeding":null,"authors":["Anson D'Aloisio","Matthew McQuinn","Oliver Maupin","Frederick B. Davies","Hy Trac","Spencer Fuller","Phoebe R. Upton Sanderbeck"],"abstract":"During reionization, the intergalactic medium is heated impulsively by supersonic ionization fronts (I-fronts). The peak gas temperatures behind the I-fronts, $T_\\mathrm{reion}$, are a key uncertainty in models of the thermal history after reionization. Here we use high-resolution radiative transfer simulations to study the parameter space of $T_\\mathrm{reion}$. We show that $T_\\mathrm{reion}$ is only mildly sensitive to the spectrum of incident radiation over most of the parameter space, with temperatures set primarily by I-front speeds. We also explore what current models of reionization predict for $T_\\mathrm{reion}$ by measuring I-front speeds in cosmological radiative transfer simulations. We find that the post-I-front temperatures evolve toward hotter values as reionization progresses. Temperatures of $T_\\mathrm{reion} = 17,000-22,000$ K are typical during the first half of reionization, but $T_\\mathrm{reion} = 25,000 - 30,000$ K may be achieved near the end of this process if I-front speeds reach $\\sim10^4$ km/s as found in our simulations. Shorter reionization epochs lead to hotter $T_\\mathrm{reion}$. We discuss implications for $z>5$ Ly$\\alpha$ forest observations, which potentially include sight lines through hot, recently reionized patches of the Universe. Interpolation tables from our parameter space study are made publicly available, along with a simple fit for the dependence of $T_\\mathrm{reion}$ on the I-front speed.","url_abs":"http://arxiv.org/abs/1807.09282v1","url_pdf":"http://arxiv.org/pdf/1807.09282v1.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":"heating-of-the-intergalactic-medium-by","repo_url":"https://github.com/frankelzeng/reionization","is_official":0,"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}