The impact of supernova feedback on the mass-metallicity relations

TL;DR

This study compares four supernova feedback methods in cosmological simulations to understand their effects on galaxy metallicity evolution, finding mechanical feedback aligns best with observations up to redshift 3.

Contribution

It introduces a systematic comparison of thermal, kinetic, stochastic, and mechanical supernova feedback methods using advanced chemodynamical simulations with updated nucleosynthesis yields.

Findings

Mechanical feedback best matches observed metallicity evolution up to z~3.

Predicted gas-phase metallicities are higher than observed at z≥1.

Feedback models can be further constrained by upcoming JWST and spectroscopic data.

Abstract

Metallicity is a fundamental physical property that strongly constrains galaxy formation and evolution. The formation of stars in galaxies is suppressed by the energy released from supernova explosions and can be enhanced by metal production. In order to understand the impact of this supernova feedback, we compare four different feedback methods, ejecting energy in thermal, kinetic, stochastic and mechanical forms, into our self-consistent cosmological chemodynamical simulations. To minimise other uncertainties, we use the latest nucleosynthesis yields that can reproduce the observed elemental abundances of stars in the Milky Way. For each method, we predict the evolution of stellar and gas-phase metallicities as a function of galaxy mass, i.e., the mass-metallicity relations. We then find that the mechanical feedback can give the best match to a number of observations up to redshift $z\sim3$, although the predicted gas-phase metallicities seem to be higher than observed at $z\ge 1$. The feedback modelling can be further constrained by the metallicities in distant galaxies with the James Web Space Telescope and those of a large sample with ongoing and future spectroscopic surveys.