{"OA_place":"publisher","scopus_import":"1","oa":1,"fulldoi":"https://doi.org/10.1051/0004-6361/202556832","citation":{"apa":"Schaerer, D., Izotov, Y. I., Marques-Chaves, R., Steidel, C. C., Reddy, N., Shapley, A. E., … Wang, B. (2026). Nitrogen abundances in star-forming galaxies 2.2 Gyr after the Big Bang are not elevated. <i>Astronomy &#38; Astrophysics</i>. EDP Sciences. <a href=\"https://doi.org/10.1051/0004-6361/202556832\">https://doi.org/10.1051/0004-6361/202556832</a>","ieee":"D. Schaerer <i>et al.</i>, “Nitrogen abundances in star-forming galaxies 2.2 Gyr after the Big Bang are not elevated,” <i>Astronomy &#38; Astrophysics</i>, vol. 708. EDP Sciences, 2026.","mla":"Schaerer, D., et al. “Nitrogen Abundances in Star-Forming Galaxies 2.2 Gyr after the Big Bang Are Not Elevated.” <i>Astronomy &#38; Astrophysics</i>, vol. 708, A242, EDP Sciences, 2026, doi:<a href=\"https://doi.org/10.1051/0004-6361/202556832\">10.1051/0004-6361/202556832</a>.","ama":"Schaerer D, Izotov YI, Marques-Chaves R, et al. Nitrogen abundances in star-forming galaxies 2.2 Gyr after the Big Bang are not elevated. <i>Astronomy &#38; Astrophysics</i>. 2026;708. doi:<a href=\"https://doi.org/10.1051/0004-6361/202556832\">10.1051/0004-6361/202556832</a>","chicago":"Schaerer, D., Y. I. Izotov, R. Marques-Chaves, C. C. Steidel, N. Reddy, A. E. Shapley, Sara Mascia, et al. “Nitrogen Abundances in Star-Forming Galaxies 2.2 Gyr after the Big Bang Are Not Elevated.” <i>Astronomy &#38; Astrophysics</i>. EDP Sciences, 2026. <a href=\"https://doi.org/10.1051/0004-6361/202556832\">https://doi.org/10.1051/0004-6361/202556832</a>.","ista":"Schaerer D, Izotov YI, Marques-Chaves R, Steidel CC, Reddy N, Shapley AE, Mascia S, Chisholm J, Flury SR, Guseva N, Heckman T, Henry A, Inoue AK, Jung I, Kusakabe H, Mawatari K, Oesch P, Östlin G, Pentericci L, Roy N, Saldana-Lopez A, Sato R, Vanzella E, Verhamme A, Wang B. 2026. Nitrogen abundances in star-forming galaxies 2.2 Gyr after the Big Bang are not elevated. Astronomy &#38; Astrophysics. 708, A242.","short":"D. Schaerer, Y.I. Izotov, R. Marques-Chaves, C.C. Steidel, N. Reddy, A.E. Shapley, S. Mascia, J. Chisholm, S.R. Flury, N. Guseva, T. Heckman, A. Henry, A.K. Inoue, I. Jung, H. Kusakabe, K. Mawatari, P. Oesch, G. Östlin, L. Pentericci, N. Roy, A. Saldana-Lopez, R. Sato, E. Vanzella, A. Verhamme, B. Wang, Astronomy &#38; Astrophysics 708 (2026)."},"publication_identifier":{"issn":["0004-6361"],"eissn":["1432-0746"]},"tmp":{"short":"CC BY (4.0)","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","image":"/images/cc_by.png","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"DOAJ_listed":"1","file_date_updated":"2026-09-09T12:55:37Z","file":[{"access_level":"open_access","success":1,"checksum":"94cc1327f363d69995984b06e18e2645","content_type":"application/pdf","creator":"dernst","date_created":"2026-09-09T12:55:37Z","date_updated":"2026-09-09T12:55:37Z","relation":"main_file","file_size":591297,"file_name":"2026_AstronomyAstrophysics_Schaerer.pdf","file_id":"22890"}],"day":"01","article_type":"original","PlanS_conform":"1","OA_type":"diamond","date_created":"2026-09-06T22:01:57Z","date_updated":"2026-09-09T12:59:51Z","doi":"10.1051/0004-6361/202556832","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","arxiv":1,"ddc":["520"],"oa_version":"Published Version","month":"04","type":"journal_article","supplementarymaterial":"no","department":[{"_id":"JoMa"}],"publisher":"EDP Sciences","article_processing_charge":"No","dataavailabilitystatement":"The data used are publicly available at the Mikulski Archive for Space Telescope (MAST),\r\nand can be accessed at https://dx.doi.org/10.17909/x6d5-vd44.","_id":"22817","quality_controlled":"1","das_tickbox":"1","external_id":{"arxiv":["2601.06968"]},"article_number":"A242","license":"https://creativecommons.org/licenses/by/4.0/","intvolume":"       708","acknowledgement":"Y.I., N.G., R.M.-C., and D.S. acknowledge support from\r\nproject No. 224866 carried out in the framework of the Joint Call “UkrainianSwiss Joint Research Projects: Call for Proposals 2023”. This work is based in\r\npart on observations made with the NASA/ESA/CSA James Webb Space Telescope. The data were obtained from the Mikulski Archive for Space Telescopes\r\nat the Space Telescope Science Institute, which is operated by the Association\r\nof Universities for Research in Astronomy, Inc., under NASA contract NAS 5-\r\n03127 for JWST. These observations are associated with program # 1869. Support for program # 1869 was provided by NASA through a grant from the Space\r\nTelescope Science Institute, which is operated by the Association of Universities\r\nfor Research in Astronomy, Inc., under NASA contract NAS 5-03127","status":"public","language":[{"iso":"eng"}],"abstract":[{"text":"Using deep, medium-resolution, JWST rest-optical spectra of a sample of typical star-forming galaxies (Lyman-break galaxies and Lyman-α emitters) from the LyC22 survey at z ∼ 3, we determined the nebular abundances of N, O, and Ne relative to H for a subsample of 25 objects with a direct method based on auroral [O III] λ4363 line detections. Our measurements increased the number of accurate N/O determinations at z ∼ 2 − 4 using a homogeneous approach. We found a mean value of log(N/O) = −+0.25−0.21 over a metallicity range of 12 + log(O/H) = 7.56 to 8.44. The observed N/O ratio and scatter are indistinguishable from that observed in low-z galaxies and H II regions over the same metallicity range, thus showing no redshift evolution of N/O for typical galaxies over a significant fraction of cosmic time. We also show that typical z ∼ 3 galaxies have a similar offset in the BPT diagram to galaxies from the low-z Lyman Continuum Survey (LzLCS) when compared to the average of SDSS galaxies, and we demonstrate that this offset is not due to enhanced nitrogen abundances. Our results establish a basis for future studies of the evolution of N and O at higher redshifts.","lang":"eng"}],"publication":"Astronomy & Astrophysics","volume":708,"year":"2026","has_accepted_license":"1","publication_status":"published","date_published":"2026-04-01T00:00:00Z","researchdata_availability":"yes","title":"Nitrogen abundances in star-forming galaxies 2.2 Gyr after the Big Bang are not elevated","author":[{"last_name":"Schaerer","first_name":"D.","full_name":"Schaerer, D."},{"last_name":"Izotov","first_name":"Y. I.","full_name":"Izotov, Y. I."},{"full_name":"Marques-Chaves, R.","last_name":"Marques-Chaves","first_name":"R."},{"full_name":"Steidel, C. C.","first_name":"C. C.","last_name":"Steidel"},{"full_name":"Reddy, N.","first_name":"N.","last_name":"Reddy"},{"last_name":"Shapley","first_name":"A. E.","full_name":"Shapley, A. E."},{"full_name":"Mascia, Sara","id":"edaf889c-c7cd-11ef-ab1b-bb28c431bd29","last_name":"Mascia","first_name":"Sara"},{"full_name":"Chisholm, J.","last_name":"Chisholm","first_name":"J."},{"full_name":"Flury, S. R.","first_name":"S. R.","last_name":"Flury"},{"last_name":"Guseva","first_name":"N.","full_name":"Guseva, N."},{"first_name":"T.","last_name":"Heckman","full_name":"Heckman, T."},{"full_name":"Henry, A.","first_name":"A.","last_name":"Henry"},{"full_name":"Inoue, A. K.","last_name":"Inoue","first_name":"A. K."},{"last_name":"Jung","first_name":"I.","full_name":"Jung, I."},{"full_name":"Kusakabe, H.","first_name":"H.","last_name":"Kusakabe"},{"first_name":"K.","last_name":"Mawatari","full_name":"Mawatari, K."},{"full_name":"Oesch, P.","last_name":"Oesch","first_name":"P."},{"full_name":"Östlin, G.","first_name":"G.","last_name":"Östlin"},{"full_name":"Pentericci, L.","first_name":"L.","last_name":"Pentericci"},{"full_name":"Roy, N.","first_name":"N.","last_name":"Roy"},{"full_name":"Saldana-Lopez, A.","last_name":"Saldana-Lopez","first_name":"A."},{"full_name":"Sato, R.","first_name":"R.","last_name":"Sato"},{"first_name":"E.","last_name":"Vanzella","full_name":"Vanzella, E."},{"first_name":"A.","last_name":"Verhamme","full_name":"Verhamme, A."},{"last_name":"Wang","first_name":"B.","full_name":"Wang, B."}]}