Cullen, F.Shapley, A.McLure, R.Dunlop, J.SSanders, R.LTopping, M.WReddy, N.AAmorin, R.Begley, R.Bolzonella, M.Calabro, A.Carnall, A.CCastellano, M.Cimatti, A.Cirasuolo, M.Cresci, G.Fontana, A.Fontanot, F.Garilli, B.Guaita, L.Hamadouche, M.Hathi, N.PMannucci, F.McLeod, D. JPentericci, L.Saxena, A.Talia, M.Zamorani, G.2021-07-092021-07-092021-05Monthly Notices of the Royal Astronomical Society Open Access Volume 505, Issue 1, Pages 903 - 9201 July 202100358711http://repositorio.unab.cl/xmlui/handle/ria/19336Indexación: ScopusWe present results from the NIRVANDELS survey on the gas-phase metallicity (Zg, tracing O/H) and stellar metallicity (Z∗, tracing Fe/H) of 33 star-forming galaxies at redshifts 2.95 < z < 3.80. Based on a combined analysis of deep optical and near-IR spectra, tracing the rest-frame far-ultraviolet (FUV; 1200-2000 Å) and rest-frame optical (3400-5500 Å), respectively, we present the first simultaneous determination of the stellar and gas-phase mass-metallicity relationships (MZRs) at z ≃ 3.4. In both cases, we find that metallicity increases with increasing stellar mass (M∗) and that the power-law slope at M∗ ≤ 1010M⊙ of both MZRs scales as Z ∝ M∗0.3. Comparing the stellar and gas-phase MZRs, we present direct evidence for super-solar O/Fe ratios (i.e. α-enhancement) at z > 3, finding (O/Fe) = 2.54 ± 0.38 × (O/Fe)⊙, with no clear dependence on M∗. © 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.enArtículo