The High-Redshift Gas-Phase Mass-Metallicity Relation in FIRE-2

Understand

The unprecedented infrared spectroscopic capabilities of JWST have provided high-quality interstellar medium (ISM) metallicity measurements and enabled characterization of the gas-phase mass-metallicity relation (MZR) for galaxies at $z \gtrsim 5$ for the first time.

• We analyze the gas-phase MZR and its evolution in a high-redshift suite of FIRE-2 cosmological zoom-in simulations at $z=5-12$ and for stellar masses $M_* \sim 10^6-10^{10} \rm{M}_\odot$.
• These simulations implement a multi-channel stellar feedback model and produce broadly realistic galaxy properties, including when evolved to $z=0$.
• The simulations predict very weak redshift evolution of the MZR over the redshift range studied, with the normalization of the MZR increasing by less than $0.01$ dex as redshift decreases from $z = 12$ to $z=5$.