{"type":"journal_article","article_number":"A10","article_processing_charge":"No","extern":"1","publication_status":"published","date_updated":"2022-07-19T09:33:46Z","publisher":"EDP Sciences","year":"2022","date_published":"2022-03-30T00:00:00Z","external_id":{"arxiv":["2111.14855"]},"oa":1,"language":[{"iso":"eng"}],"quality_controlled":"1","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","article_type":"original","abstract":[{"lang":"eng","text":"Directly characterising the first generations of stars in distant galaxies is a key quest of observational cosmology. We present a case study of ID53 at z = 4.77, the UV-brightest (but L⋆) star-forming galaxy at z > 3 in the MUSE eXtremely Deep Field with a mass of ≈109 M⊙. In addition to very strong Lyman-α (Lyα) emission, we clearly detect the (stellar) continuum and an N V P Cygni feature, interstellar absorption, fine-structure emission and nebular C IV emission lines in the 140 h spectrum. Continuum emission from two spatially resolved components in Hubble Space Telescope data are blended in the MUSE data, but we show that the nebular C IV emission originates from a subcomponent of the galaxy. The UV spectrum can be fit with recent BPASS stellar population models combined with single-burst or continuous star formation histories (SFHs), a standard initial mass function, and an attenuation law. Models with a young age and low metallicity (log10(age/yr) = 6.5–7.6 and [Z/H] = −2.15 to −1.15) are preferred, but the details depend on the assumed SFH. The intrinsic Hα luminosity of the best-fit models is an order of magnitude higher than the Hα luminosity inferred from Spitzer/IRAC data, which either suggests a high escape fraction of ionising photons, a high relative attenuation of nebular to stellar dust, or a complex SFH. The metallicity appears lower than the metallicity in more massive galaxies at z = 3 − 5, consistent with the scenario according to which younger galaxies have lower metallicities. This chemical immaturity likely facilitates Lyα escape, explaining why the Lyα equivalent width is anti-correlated with stellar metallicity. Finally, we stress that uncertainties in SFHs impose a challenge for future inferences of the stellar metallicity of young galaxies. This highlights the need for joint (spatially resolved) analyses of stellar spectra and photo-ionisation models."}],"publication_identifier":{"eissn":["1432-0746"],"issn":["0004-6361"]},"month":"03","doi":"10.1051/0004-6361/202142187","acknowledgement":"We thank the referee for thoughtful and constructive comments that have improved the quality of this manuscript. Based on observations collected at the European Southern Observatory under ESO programme 1101.A-0127. This work made use of v2.2.1 of the Binary Population and Spectral Synthesis (BPASS) models as described in Eldridge et al. (2017) and Stanway & Eldridge (2018). A.F. acknowledges the support from grant PRIN MIUR2017-20173ML3WW_001. T.N. acknowledges support from Australian Research Council Laureate Fellowship FL180100060.","main_file_link":[{"open_access":"1","url":"https://arxiv.org/abs/2111.14855"}],"_id":"11490","status":"public","oa_version":"Published Version","keyword":["Space and Planetary Science","Astronomy and Astrophysics","galaxies: high-redshift / techniques: spectroscopic / galaxies: stellar content / galaxies: formation"],"volume":660,"publication":"Astronomy & Astrophysics","citation":{"ista":"Matthee JJ, Feltre A, Maseda M, Nanayakkara T, Boogaard L, Bacon R, Verhamme A, Leclercq F, Kusakabe H, Urrutia T, Wisotzki L. 2022. Deciphering stellar metallicities in the early universe: Case study of a young galaxy at z = 4.77 in the MUSE eXtremely Deep Field. Astronomy & Astrophysics. 660, A10.","short":"J.J. Matthee, A. Feltre, M. Maseda, T. Nanayakkara, L. Boogaard, R. Bacon, A. Verhamme, F. Leclercq, H. Kusakabe, T. Urrutia, L. Wisotzki, Astronomy & Astrophysics 660 (2022).","chicago":"Matthee, Jorryt J, Anna Feltre, Michael Maseda, Themiya Nanayakkara, Leindert Boogaard, Roland Bacon, Anne Verhamme, et al. “Deciphering Stellar Metallicities in the Early Universe: Case Study of a Young Galaxy at z = 4.77 in the MUSE EXtremely Deep Field.” Astronomy & Astrophysics. EDP Sciences, 2022. https://doi.org/10.1051/0004-6361/202142187.","ama":"Matthee JJ, Feltre A, Maseda M, et al. Deciphering stellar metallicities in the early universe: Case study of a young galaxy at z = 4.77 in the MUSE eXtremely Deep Field. Astronomy & Astrophysics. 2022;660. doi:10.1051/0004-6361/202142187","ieee":"J. J. Matthee et al., “Deciphering stellar metallicities in the early universe: Case study of a young galaxy at z = 4.77 in the MUSE eXtremely Deep Field,” Astronomy & Astrophysics, vol. 660. EDP Sciences, 2022.","apa":"Matthee, J. J., Feltre, A., Maseda, M., Nanayakkara, T., Boogaard, L., Bacon, R., … Wisotzki, L. (2022). Deciphering stellar metallicities in the early universe: Case study of a young galaxy at z = 4.77 in the MUSE eXtremely Deep Field. Astronomy & Astrophysics. EDP Sciences. https://doi.org/10.1051/0004-6361/202142187","mla":"Matthee, Jorryt J., et al. “Deciphering Stellar Metallicities in the Early Universe: Case Study of a Young Galaxy at z = 4.77 in the MUSE EXtremely Deep Field.” Astronomy & Astrophysics, vol. 660, A10, EDP Sciences, 2022, doi:10.1051/0004-6361/202142187."},"day":"30","title":"Deciphering stellar metallicities in the early universe: Case study of a young galaxy at z = 4.77 in the MUSE eXtremely Deep Field","author":[{"full_name":"Matthee, Jorryt J","id":"7439a258-f3c0-11ec-9501-9df22fe06720","orcid":"0000-0003-2871-127X","last_name":"Matthee","first_name":"Jorryt J"},{"last_name":"Feltre","full_name":"Feltre, Anna","first_name":"Anna"},{"first_name":"Michael","full_name":"Maseda, Michael","last_name":"Maseda"},{"last_name":"Nanayakkara","full_name":"Nanayakkara, Themiya","first_name":"Themiya"},{"full_name":"Boogaard, Leindert","last_name":"Boogaard","first_name":"Leindert"},{"last_name":"Bacon","full_name":"Bacon, Roland","first_name":"Roland"},{"first_name":"Anne","last_name":"Verhamme","full_name":"Verhamme, Anne"},{"first_name":"Floriane","last_name":"Leclercq","full_name":"Leclercq, Floriane"},{"full_name":"Kusakabe, Haruka","last_name":"Kusakabe","first_name":"Haruka"},{"first_name":"Tanya","last_name":"Urrutia","full_name":"Urrutia, Tanya"},{"first_name":"Lutz","full_name":"Wisotzki, Lutz","last_name":"Wisotzki"}],"date_created":"2022-07-05T15:25:35Z","intvolume":" 660","scopus_import":"1"}