{"external_id":{"arxiv":["1609.05897"]},"page":"1242-1258","status":"public","oa":1,"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","article_processing_charge":"No","acknowledgement":"We thank the reviewer for his/her helpful comments and suggestions that have greatly improved this work. DS and JM acknowledge financial support from the Netherlands Organisation for Scientific research (NWO) through a Veni fellowship. DS also acknowledges funding from FCT through an FCT Investigator Starting Grant and Start-up Grant (IF/01154/2012/CP0189/CT0010). PNB is grateful for support from the UK STFC via grant ST/M001229/1. IRS acknowledges support from STFC (ST/L00075X/1), the ERC Advanced Investigator programme DUSTYGAL 321334 and a Royal Society/Wolfson merit award. We thank Matthew Hayes, Ryan Trainor, Kimihiko Nakajima and Anne Verhamme for many helpful discussions and Ana Sobral, Carolina Duarte and Miguel Domingos for taking part in observations with the NB392 filter. We also thank Sergio Santos for helpful comments. This research is based on observations obtained on the Isaac Newton Telescope (INT), programs: I13AN002, I14AN002, 088-INT7/14A, I14BN006, 118-INT13/14B & I15AN008. The authors acknowledge the award of time from programmes: I13AN002, I14AN002, 088-INT7/14A, I14BN006, 118-INT13/14B, I15AN008 on the INT. INT is operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. Based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 098.A 0819. We have benefited greatly from the publicly available programming language PYTHON, including the NUMPY, MATPLOTLIB, PYFITS, SCIPY and ASTROPY packages, the astronomical imaging tools SEXTRACTOR, SWARP (Bertin & Arnouts 1996; Bertin 2010), SCAMP (Bertin 2006) and TOPCAT (Taylor 2005). Dedicated to the memory of M. L. Nicolau and M. C. Serrano.","date_created":"2022-07-12T12:04:16Z","month":"04","citation":{"short":"D. Sobral, J.J. Matthee, P. Best, A. Stroe, H. Röttgering, I. Oteo, I. Smail, L. Morabito, A. Paulino-Afonso, Monthly Notices of the Royal Astronomical Society 466 (2017) 1242–1258.","mla":"Sobral, David, et al. “The CALYMHA Survey: Lyα Luminosity Function and Global Escape Fraction of Lyα Photons at z = 2.23.” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 466, no. 1, Oxford University Press, 2017, pp. 1242–58, doi:<a href=\"https://doi.org/10.1093/mnras/stw3090\">10.1093/mnras/stw3090</a>.","ama":"Sobral D, Matthee JJ, Best P, et al. The CALYMHA survey: Lyα luminosity function and global escape fraction of Lyα photons at z = 2.23. <i>Monthly Notices of the Royal Astronomical Society</i>. 2017;466(1):1242-1258. doi:<a href=\"https://doi.org/10.1093/mnras/stw3090\">10.1093/mnras/stw3090</a>","ieee":"D. Sobral <i>et al.</i>, “The CALYMHA survey: Lyα luminosity function and global escape fraction of Lyα photons at z = 2.23,” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 466, no. 1. Oxford University Press, pp. 1242–1258, 2017.","chicago":"Sobral, David, Jorryt J Matthee, Philip Best, Andra Stroe, Huub Röttgering, Iván Oteo, Ian Smail, Leah Morabito, and Ana Paulino-Afonso. “The CALYMHA Survey: Lyα Luminosity Function and Global Escape Fraction of Lyα Photons at z = 2.23.” <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford University Press, 2017. <a href=\"https://doi.org/10.1093/mnras/stw3090\">https://doi.org/10.1093/mnras/stw3090</a>.","ista":"Sobral D, Matthee JJ, Best P, Stroe A, Röttgering H, Oteo I, Smail I, Morabito L, Paulino-Afonso A. 2017. The CALYMHA survey: Lyα luminosity function and global escape fraction of Lyα photons at z = 2.23. Monthly Notices of the Royal Astronomical Society. 466(1), 1242–1258.","apa":"Sobral, D., Matthee, J. J., Best, P., Stroe, A., Röttgering, H., Oteo, I., … Paulino-Afonso, A. (2017). The CALYMHA survey: Lyα luminosity function and global escape fraction of Lyα photons at z = 2.23. <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford University Press. <a href=\"https://doi.org/10.1093/mnras/stw3090\">https://doi.org/10.1093/mnras/stw3090</a>"},"author":[{"full_name":"Sobral, David","first_name":"David","last_name":"Sobral"},{"last_name":"Matthee","id":"7439a258-f3c0-11ec-9501-9df22fe06720","full_name":"Matthee, Jorryt J","first_name":"Jorryt J","orcid":"0000-0003-2871-127X"},{"full_name":"Best, Philip","first_name":"Philip","last_name":"Best"},{"first_name":"Andra","full_name":"Stroe, Andra","last_name":"Stroe"},{"last_name":"Röttgering","full_name":"Röttgering, Huub","first_name":"Huub"},{"last_name":"Oteo","first_name":"Iván","full_name":"Oteo, Iván"},{"last_name":"Smail","first_name":"Ian","full_name":"Smail, Ian"},{"full_name":"Morabito, Leah","first_name":"Leah","last_name":"Morabito"},{"last_name":"Paulino-Afonso","full_name":"Paulino-Afonso, Ana","first_name":"Ana"}],"doi":"10.1093/mnras/stw3090","_id":"11562","abstract":[{"text":"We present the CAlibrating LYMan-α with Hα (CALYMHA) pilot survey and new results on Lyman α (Lyα) selected galaxies at z ∼ 2. We use a custom-built Lyα narrow-band filter at the Isaac Newton Telescope, designed to provide a matched volume coverage to the z = 2.23 Hα HiZELS survey. Here, we present the first results for the COSMOS and UDS fields. Our survey currently reaches a 3σ line flux limit of ∼4 × 10−17 erg s−1 cm−2, and a Lyα luminosity limit of ∼1042.3 erg s−1. We find 188 Lyα emitters over 7.3 × 105 Mpc3, but also find significant numbers of other line-emitting sources corresponding to He II, C III] and C IV emission lines. These sources are important contaminants, and we carefully remove them, unlike most previous studies. We find that the Lyα luminosity function at z = 2.23 is very well described by a Schechter function up to LLy α ≈ 1043 erg s−1 with L∗=1042.59+0.16−0.08 erg s−1, ϕ∗=10−3.09+0.14−0.34 Mpc−3 and α = −1.75 ± 0.25. Above LLy α ≈ 1043 erg s−1, the Lyα luminosity function becomes power-law like, driven by X-ray AGN. We find that Lyα-selected emitters have a high escape fraction of 37 ± 7 per cent, anticorrelated with Lyα luminosity and correlated with Lyα equivalent width. Lyα emitters have ubiquitous large (≈40 kpc) Lyα haloes, ∼2 times larger than their Hα extents. By directly comparing our Lyα and Hα luminosity functions, we find that the global/overall escape fraction of Lyα photons (within a 13 kpc radius) from the full population of star-forming galaxies is 5.1 ± 0.2 per cent at the peak of the star formation history. An extra 3.3 ± 0.3 per cent of Lyα photons likely still escape, but at larger radii.","lang":"eng"}],"publication_status":"published","publication":"Monthly Notices of the Royal Astronomical Society","type":"journal_article","extern":"1","volume":466,"date_updated":"2022-08-19T07:18:20Z","publication_identifier":{"eissn":["1365-2966"],"issn":["0035-8711"]},"day":"01","publisher":"Oxford University Press","year":"2017","article_type":"original","date_published":"2017-04-01T00:00:00Z","keyword":["Space and Planetary Science","Astronomy and Astrophysics","galaxies: evolution","galaxies: haloes","galaxies: high-redshift","galaxies: luminosity function","mass function","galaxies: statistics","cosmology: observations"],"title":"The CALYMHA survey: Lyα luminosity function and global escape fraction of Lyα photons at z = 2.23","quality_controlled":"1","scopus_import":"1","main_file_link":[{"url":"https://arxiv.org/abs/1609.05897","open_access":"1"}],"oa_version":"Preprint","issue":"1","language":[{"iso":"eng"}],"intvolume":"       466"}