{"abstract":[{"text":"The increasingly neutral intergalactic gas at z > 6 impacts the Lyman-α (Lyα) flux observed from galaxies. One luminous galaxy, COLA1, stands out because of its unique double-peaked Lyα line at z = 6.6, unseen in any simulation of reionization. Here, we present JWST/NIRCam wide-field slitless spectroscopy in a 21 arcmin2 field centered on COLA1. We find 141 galaxies spectroscopically selected through the [O III] doublet at 5.35 < z < 6.95, with 40 of these sources showing Hβ. For COLA1, we additionally detect [O III]4363 as well as Hγ. We measure a systemic redshift of z = 6.5917 for COLA1, confirming the classical double-peak nature of the Lyα profile. This implies that it resides in a highly ionized bubble and that it is leaking ionizing photons with a high escape fraction of fesc(LyC) = 20–50%, making it a prime laboratory to study Lyman continuum escape in the Epoch of Reionization. COLA1 shows all the signs of a prolific ionizer with a Lyα escape fraction of 81 ± 5%, Balmer decrement indicating no dust, a steep UV slope (βUV = −3.2 ± 0.4), and a star-formation surface density ≳10× that of typical galaxies at similar redshift. We detect five galaxies in COLA1’s close environment (Δz < 0.02). Exploiting the high spectroscopic completeness inherent to grism surveys, and using mock simulations that fully mimic the selection function, we show that the number of detected companions is very typical for a normal similarly UV-bright (MUV ∼ −21.3) galaxy – that is, the ionized bubble around COLA1 is unlikely to be due to an excessively large over-density. Instead, the measured ionizing properties suggest that COLA1 by itself might be powering the bubble required to explain its double-peaked Lyα profile (Rion ≈ 0.7 pMpc), with only minor contributions from detected neighbors (−19.5 ≲ MUV ≲ −17.5).","lang":"eng"}],"month":"09","file":[{"date_created":"2024-09-11T07:35:00Z","creator":"dernst","file_name":"2024_AstronomyAstrophysics_TorralbaTorregrosa.pdf","success":1,"file_id":"18055","checksum":"a6c0df287c75e8929db9f42badeac859","file_size":6225413,"date_updated":"2024-09-11T07:35:00Z","content_type":"application/pdf","relation":"main_file","access_level":"open_access"}],"article_number":"A44","publication_identifier":{"eissn":["1432-0746"],"issn":["0004-6361"]},"scopus_import":"1","date_updated":"2024-09-11T07:35:13Z","quality_controlled":"1","date_published":"2024-09-01T00:00:00Z","tmp":{"legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","short":"CC BY (4.0)","image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"department":[{"_id":"JoMa"}],"file_date_updated":"2024-09-11T07:35:00Z","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","publication_status":"published","article_type":"original","publisher":"EDP Sciences","status":"public","intvolume":"       689","year":"2024","publication":"Astronomy and Astrophysics","_id":"17889","citation":{"ama":"Torralba-Torregrosa A, Matthee JJ, Naidu RP, et al. Anatomy of an ionized bubble: NIRCam grism spectroscopy of the z = 6.6 double-peaked Lyman- α emitter COLA1 and its environment. <i>Astronomy and Astrophysics</i>. 2024;689. doi:<a href=\"https://doi.org/10.1051/0004-6361/202450318\">10.1051/0004-6361/202450318</a>","ieee":"A. Torralba-Torregrosa <i>et al.</i>, “Anatomy of an ionized bubble: NIRCam grism spectroscopy of the z = 6.6 double-peaked Lyman- α emitter COLA1 and its environment,” <i>Astronomy and Astrophysics</i>, vol. 689. EDP Sciences, 2024.","ista":"Torralba-Torregrosa A, Matthee JJ, Naidu RP, Mackenzie R, Pezzulli G, Hutter A, Arnalte-Mur P, Gurung-López S, Tacchella S, Oesch P, Kashino D, Conroy C, Sobral D. 2024. Anatomy of an ionized bubble: NIRCam grism spectroscopy of the z = 6.6 double-peaked Lyman- α emitter COLA1 and its environment. Astronomy and Astrophysics. 689, A44.","chicago":"Torralba-Torregrosa, Alberto, Jorryt J Matthee, Rohan P. Naidu, Ruari Mackenzie, Gabriele Pezzulli, Anne Hutter, Pablo Arnalte-Mur, et al. “Anatomy of an Ionized Bubble: NIRCam Grism Spectroscopy of the z = 6.6 Double-Peaked Lyman- α Emitter COLA1 and Its Environment.” <i>Astronomy and Astrophysics</i>. EDP Sciences, 2024. <a href=\"https://doi.org/10.1051/0004-6361/202450318\">https://doi.org/10.1051/0004-6361/202450318</a>.","apa":"Torralba-Torregrosa, A., Matthee, J. J., Naidu, R. P., Mackenzie, R., Pezzulli, G., Hutter, A., … Sobral, D. (2024). Anatomy of an ionized bubble: NIRCam grism spectroscopy of the z = 6.6 double-peaked Lyman- α emitter COLA1 and its environment. <i>Astronomy and Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/202450318\">https://doi.org/10.1051/0004-6361/202450318</a>","short":"A. Torralba-Torregrosa, J.J. Matthee, R.P. Naidu, R. Mackenzie, G. Pezzulli, A. Hutter, P. Arnalte-Mur, S. Gurung-López, S. Tacchella, P. Oesch, D. Kashino, C. Conroy, D. Sobral, Astronomy and Astrophysics 689 (2024).","mla":"Torralba-Torregrosa, Alberto, et al. “Anatomy of an Ionized Bubble: NIRCam Grism Spectroscopy of the z = 6.6 Double-Peaked Lyman- α Emitter COLA1 and Its Environment.” <i>Astronomy and Astrophysics</i>, vol. 689, A44, EDP Sciences, 2024, doi:<a href=\"https://doi.org/10.1051/0004-6361/202450318\">10.1051/0004-6361/202450318</a>."},"title":"Anatomy of an ionized bubble: NIRCam grism spectroscopy of the z = 6.6 double-peaked Lyman- α emitter COLA1 and its environment","article_processing_charge":"Yes (in subscription journal)","acknowledgement":"The authors acknowledge the financial support from the MICIU with funding from the European Union NextGenerationEU and Generalitat Valenciana in the call Programa de Planes Complementarios de I+D+i (PRTR 2022) Project (VAL-JPAS), reference ASFAE/2022/025. This work has been funded by project PID2019-109592GBI00/AEI/10.13039/501100011033 from the Spanish Ministerio de Ciencia e Innovación (MCIN)-Agencia Estatal de Investigación, by the Project of Excellence Prometeo/2020/085 from the Conselleria d’Innovació Universitats, Ciència i Societat Digital de la Generalitat Valenciana. It has also be funded by the Project of Excellence Prometeo/2020/085 from the Conselleria d’Educació, Universitats, i Ocupació de la Generalitat Valenciana. Funded by the European Union (ERC, AGENTS, 101076224). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them. ST acknowledges support by the Royal Society Research Grant G125142. AH acknowledges support by the VILLUM FONDEN under grant 37459. The Cosmic Dawn Center (DAWN) is funded by the Danish National Research Foundation under grant DNRF140. We acknowledge funding from JWST program GO-1933. Support for this work was provided by NASA through the NASA Hubble Fellowship grant HST-HF2-51515.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. This work has received funding from the Swiss State Secretariat for Education, Research and Innovation (SERI) under contract number MB22.00072, as well as from the Swiss National Science Foundation (SNSF) through project grant 200020_207349. This work is based on observations made with the NASA/ESA/CSA James Webb Space Telescope. The data were obtained from the Mikulski Archive for Space Telescopes at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-03127 for JWST. These observations are associated with program # 1933. The specific observations analyzed can be accessed via https://doi.org/10.17909/s9ht-7n34.","oa":1,"date_created":"2024-09-08T22:01:11Z","author":[{"full_name":"Torralba-Torregrosa, Alberto","last_name":"Torralba-Torregrosa","first_name":"Alberto"},{"orcid":"0000-0003-2871-127X","id":"7439a258-f3c0-11ec-9501-9df22fe06720","full_name":"Matthee, Jorryt J","last_name":"Matthee","first_name":"Jorryt J"},{"full_name":"Naidu, Rohan P.","last_name":"Naidu","first_name":"Rohan P."},{"first_name":"Ruari","full_name":"Mackenzie, Ruari","last_name":"Mackenzie"},{"first_name":"Gabriele","last_name":"Pezzulli","full_name":"Pezzulli, Gabriele"},{"full_name":"Hutter, Anne","last_name":"Hutter","first_name":"Anne"},{"last_name":"Arnalte-Mur","full_name":"Arnalte-Mur, Pablo","first_name":"Pablo"},{"last_name":"Gurung-López","full_name":"Gurung-López, Siddhartha","first_name":"Siddhartha"},{"first_name":"Sandro","full_name":"Tacchella, Sandro","last_name":"Tacchella"},{"last_name":"Oesch","full_name":"Oesch, Pascal","first_name":"Pascal"},{"last_name":"Kashino","full_name":"Kashino, Daichi","first_name":"Daichi"},{"full_name":"Conroy, Charlie","last_name":"Conroy","first_name":"Charlie"},{"full_name":"Sobral, David","last_name":"Sobral","first_name":"David"}],"volume":689,"oa_version":"Published Version","language":[{"iso":"eng"}],"type":"journal_article","has_accepted_license":"1","ddc":["520"],"day":"01","doi":"10.1051/0004-6361/202450318","external_id":{"arxiv":["2404.10040"]}}