Star formation and chemical enrichment in protoclusters

Abstract

We examine star formation and chemical enrichment in protoclusters (PCs) using cosmological zoom-in hydrodynamic simulations. We find that the total star formation rate (SFR) in all PC (M·) reaches at z = 3, equivalent to the observed PCs. The SFR in the Core region accounts for about 30 per cent of the total star formation in the PC at z 1, suggesting the importance of the outer regions to reveal the evolution of galaxy clusters. We find that the total SFR of PC is dominated by galaxies with stellar masses, while more massive galaxies dominate the SFR in the Core. For the chemical abundance evolution, we find that the higher-density region has a higher metallicity and faster evolution. We show that the [O/Fe] versus [Fe/H] relation turns down in the Core at z = 3.4 due to the enrichment of Fe by Type Ia supernovae. We find no environmental effects for the mass-metallicity relations (MZR) or log (N/O) versus 12 + log (O/H) for galaxies. We find that the chemical enrichment in galaxy clusters proceeds faster in the high-redshift universe (z > 1). Our work will benefit future tomographic observations, particularly using PCs as unique probes of accelerated structure formation and evolution in high-density regions of the universe.