SIMBAD references

Observations and semianalytical galaxy formation and evolution models (SAMs) have suggested the existence of a stellar mass-stellar metallicity relation (MZR), which is shown to be universal for different types of galaxies over a large range of stellar masses (M_* ∼ 10³-10¹¹ M_☉) and dark matter halo masses (M_halo ∼ 10⁹-10¹⁵ h^–1 M_☉). In this work, we construct a chemical evolution model to investigate the origin of the MZR, including both the effects of gas inflows and outflows in galaxies. We solve the MZR from the chemical evolution model by assuming that the cold gas mass (M_cold) and the stellar feedback efficiency (β) follow some power-law scaling relationships with M_* during the growth of a galaxy, i.e., M_cold∝M_*^α_gs and β∝M_*^α_βs_. We use the SAM to obtain these power-law scaling relations, which appear to be roughly universal over a large range of stellar masses for both satellites and central galaxies within a large range of halo masses. The range of MZRs produced by our models is in a narrow space, which provides support to the universality of the MZRs. The formation of the MZR is a result caused jointly by the cold gas fraction decreasing with increasing M_* and by the stellar feedback efficiency decreasing with increasing M_* in the galaxy growth, and the exponent in the MZR is around -α_βs or 1 - α_gs. The MZR represents an "average" evolutionary track for the stellar metallicity of a galaxy. The comparison of our model with some previous models for the origin of MZRs is also discussed.