The Gas-phase Mass–Metallicity Relation for Massive Galaxies at z ∼ 0.7 with the LEGA-C Survey
Journal
The Astrophysical Journal
Journal Volume
964
Journal Issue
1
Start Page
59
ISSN
0004-637X
1538-4357
Date Issued
2024-03-01
Author(s)
Zach J. Lewis
Brett H. Andrews
Rachel Bezanson
Michael Maseda
Eric F. Bell
Romeel Davé
Francesco D’Eugenio
Marijn Franx
Anna Gallazzi
Anna de Graaff
Yasha Kaushal
Angelos Nersesian
Jeffrey A. Newman
Arjen van der Wel
Abstract
The massive end of the gas-phase mass-metallicity relation (MZR) is a sensitive probe of active galactic nuclei (AGN) feedback that is a crucial but highly uncertain component of galaxy evolution models. In this paper, we extend the z ∼ 0.7 MZR by ∼0.5 dex up to log (M ⋆/M ⊙) ∼ 11.1. We use extremely deep VLT VIMOS spectra from the Large Early Galaxy Astrophysics Census (LEGA-C) survey to measure metallicities for 145 galaxies. The LEGA-C MZR matches the normalization of the z ∼ 0.8 DEEP2 MZR where they overlap, so we combine the two to create an MZR spanning from 9.3 to 11.1 log (M ⋆/M ⊙). The LEGA-C+DEEP2 MZR at z ∼ 0.7 is offset to slightly lower metallicities (0.05-0.13 dex) than the z ∼ 0 MZR, but it otherwise mirrors the established power-law rise at low/intermediate stellar masses and asymptotic flattening at high stellar masses. We compare the LEGA-C+DEEP2 MZR to the MZR from two cosmological simulations (IllustrisTNG and SIMBA), which predict qualitatively different metallicity trends for high-mass galaxies. This comparison highlights that our extended MZR provides a crucial observational constraint for galaxy evolution models in a mass regime where the MZR is very sensitive to choices about the implementation of AGN feedback.
Publisher
American Astronomical Society
Type
journal article