{"abstract":[{"lang":"eng","text":"The cosmic ionizing emissivity from star-forming galaxies has long been anchored to UV luminosity functions. Here, we introduce an emissivity framework based on Lyα emitters (LAEs), which naturally hones in on the subset of galaxies responsible for the ionizing background due to the intimate connection between production and escape of Lyα and LyC photons. Using constraints on the escape fractions of bright LAEs (LLyα > 0.2L*) at z ≈ 2 obtained from resolved Lyα profiles, and arguing for their redshift-invariance, we show that: (i) quasars and LAEs together reproduce the relatively flat emissivity at z ≈ 2–6, which is non-trivial given the strong evolution in both the star formation density and quasar number density at these epochs and (ii) LAEs produce late and rapid reionization between z ≈ 6−9 under plausible assumptions. Within this framework, the >10 × rise in the UV population-averaged fesc between z ≈ 3–7 naturally arises due to the same phenomena that drive the growing LAE fraction with redshift. Generally, a LAE dominated emissivity yields a peak in the distribution of the ionizing budget with UV luminosity as reported in latest simulations. Using our adopted parameters (⁠fesc=50 per cent⁠, ξion = 1025.9 Hz erg−1 for half the bright LAEs), a highly ionizing minority of galaxies with MUV < −17 accounts for the entire ionizing budget from star-forming galaxies. Rapid flashes of LyC from such rare galaxies produce a ‘disco’ ionizing background. We conclude proposing tests to further develop our suggested Lyα-anchored formalism."}],"main_file_link":[{"url":"https://arxiv.org/abs/2110.11967","open_access":"1"}],"publication_status":"published","date_published":"2022-06-01T00:00:00Z","extern":"1","issue":"4","article_processing_charge":"No","month":"06","date_updated":"2022-08-18T10:42:47Z","type":"journal_article","day":"01","title":"(Re)Solving reionization with Lyα: How bright Lyα emitters account for the z ≈ 2 − 8 cosmic ionizing background","quality_controlled":"1","status":"public","publisher":"Oxford University Press","scopus_import":"1","oa_version":"Preprint","oa":1,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","date_created":"2022-07-07T09:21:30Z","_id":"11521","language":[{"iso":"eng"}],"article_type":"original","citation":{"apa":"Matthee, J. J., Naidu, R. P., Pezzulli, G., Gronke, M., Sobral, D., Oesch, P. A., … Röttgering, H. (2022). (Re)Solving reionization with Lyα: How bright Lyα emitters account for the z ≈ 2 − 8 cosmic ionizing background. <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford University Press. <a href=\"https://doi.org/10.1093/mnras/stac801\">https://doi.org/10.1093/mnras/stac801</a>","ista":"Matthee JJ, Naidu RP, Pezzulli G, Gronke M, Sobral D, Oesch PA, Hayes M, Erb D, Schaerer D, Amorín R, Tacchella S, Ana Paulino-Afonso AP-A, Llerena M, Calhau J, Röttgering H. 2022. (Re)Solving reionization with Lyα: How bright Lyα emitters account for the z ≈ 2 − 8 cosmic ionizing background. Monthly Notices of the Royal Astronomical Society. 512(4), 5960–5977.","chicago":"Matthee, Jorryt J, Rohan P. Naidu, Gabriele Pezzulli, Max Gronke, David Sobral, Pascal A. Oesch, Matthew Hayes, et al. “(Re)Solving Reionization with Lyα: How Bright Lyα Emitters Account for the z ≈ 2 − 8 Cosmic Ionizing Background.” <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford University Press, 2022. <a href=\"https://doi.org/10.1093/mnras/stac801\">https://doi.org/10.1093/mnras/stac801</a>.","ama":"Matthee JJ, Naidu RP, Pezzulli G, et al. (Re)Solving reionization with Lyα: How bright Lyα emitters account for the z ≈ 2 − 8 cosmic ionizing background. <i>Monthly Notices of the Royal Astronomical Society</i>. 2022;512(4):5960-5977. doi:<a href=\"https://doi.org/10.1093/mnras/stac801\">10.1093/mnras/stac801</a>","short":"J.J. Matthee, R.P. Naidu, G. Pezzulli, M. Gronke, D. Sobral, P.A. Oesch, M. Hayes, D. Erb, D. Schaerer, R. Amorín, S. Tacchella, A.P.-A. Ana Paulino-Afonso, M. Llerena, J. Calhau, H. Röttgering, Monthly Notices of the Royal Astronomical Society 512 (2022) 5960–5977.","mla":"Matthee, Jorryt J., et al. “(Re)Solving Reionization with Lyα: How Bright Lyα Emitters Account for the z ≈ 2 − 8 Cosmic Ionizing Background.” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 512, no. 4, Oxford University Press, 2022, pp. 5960–77, doi:<a href=\"https://doi.org/10.1093/mnras/stac801\">10.1093/mnras/stac801</a>.","ieee":"J. J. Matthee <i>et al.</i>, “(Re)Solving reionization with Lyα: How bright Lyα emitters account for the z ≈ 2 − 8 cosmic ionizing background,” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 512, no. 4. Oxford University Press, pp. 5960–5977, 2022."},"external_id":{"arxiv":["2110.11967"]},"publication_identifier":{"eissn":["1365-2966"],"issn":["0035-8711"]},"author":[{"full_name":"Matthee, Jorryt J","id":"7439a258-f3c0-11ec-9501-9df22fe06720","last_name":"Matthee","first_name":"Jorryt J","orcid":"0000-0003-2871-127X"},{"full_name":"Naidu, Rohan P.","first_name":"Rohan P.","last_name":"Naidu"},{"full_name":"Pezzulli, Gabriele","last_name":"Pezzulli","first_name":"Gabriele"},{"full_name":"Gronke, Max","last_name":"Gronke","first_name":"Max"},{"last_name":"Sobral","first_name":"David","full_name":"Sobral, David"},{"first_name":"Pascal A.","last_name":"Oesch","full_name":"Oesch, Pascal A."},{"last_name":"Hayes","first_name":"Matthew","full_name":"Hayes, Matthew"},{"full_name":"Erb, Dawn","first_name":"Dawn","last_name":"Erb"},{"first_name":"Daniel","last_name":"Schaerer","full_name":"Schaerer, Daniel"},{"full_name":"Amorín, Ricardo","last_name":"Amorín","first_name":"Ricardo"},{"full_name":"Tacchella, Sandro","first_name":"Sandro","last_name":"Tacchella"},{"first_name":"Ana Paulino-Afonso","last_name":"Ana Paulino-Afonso","full_name":"Ana Paulino-Afonso, Ana Paulino-Afonso"},{"full_name":"Llerena, Mario","first_name":"Mario","last_name":"Llerena"},{"first_name":"João","last_name":"Calhau","full_name":"Calhau, João"},{"last_name":"Röttgering","first_name":"Huub","full_name":"Röttgering, Huub"}],"publication":"Monthly Notices of the Royal Astronomical Society","page":"5960-5977","doi":"10.1093/mnras/stac801","acknowledgement":"We thank an anonymous referee for an encouraging and constructive report that helped improving the quality of this work. We acknowledge illuminating conversations with Xiaohan Wu, Chris Cain, Anna-Christina Eilers, Simon Lilly and Ruari Mackenzie. RPN gratefully acknowledges an Ashford Fellowship granted by Harvard University. MG was supported by NASA through the NASA Hubble Fellowship grant HST-HF2-51409. PO acknowledges support from the Swiss National Science Foundation through the SNSF Professorship grant 190079. GP acknowledges support from the Netherlands Research School for Astronomy (NOVA). MH is fellow of the Knut and Alice Wallenberg Foundation. DE is supported by the US National Science Foundation (NSF) through Astronomy & Astrophysics grant AST-1909198. The Cosmic Dawn Center (DAWN) is funded by the Danish National Research Foundation under grant No. 140. RA acknowledges support from Fondecyt Regular Grant 1202007. ST is supported by the 2021 Research Fund 1.210134.01 of UNIST (Ulsan National Institute of Science & Technology). MLl acknowledges support from the ANID/Scholarship Program/Doctorado Nacional/2019-21191036. JC acknowledges support from the Spanish Ministry of Science and Innovation, project PID2019-107408GB-C43 (ESTALLIDOS) and from Gobierno de Canarias through EU FEDER funding, project PID2020010050.","keyword":["galaxies: high-redshift","intergalactic medium","cosmology: observations","dark ages","reionization","first stars","ultraviolet: galaxies"],"year":"2022","intvolume":"       512","volume":512}