Galaxy properties in the cosmic web of EAGLE simulation

TL;DR

This study uses the EAGLE simulation to analyze how galaxy properties vary across different cosmic web environments, revealing significant environmental influences on galaxy evolution and characteristics.

Contribution

It provides a detailed analysis of galaxy property dependence on cosmic web environments using the latest hydrodynamic simulation, highlighting environmental effects on galaxy evolution.

Findings

Baryon fractions decrease from knots to voids.

Characteristic halo mass of 10^12 h^-1 M_sun shows reversed stellar-to-halo mass ratio.

Environmental effects weaken at higher redshifts for most properties.

Abstract

We investigate the dependence of the galaxy properties on cosmic web environments using the most up-to-date hydrodynamic simulation: Evolution and Assembly of Galaxies and their Environments (EAGLE). The baryon fractions in haloes and the amplitudes of the galaxy luminosity function decrease going from knots to filaments to sheets to voids. Interestingly, the value of L$^*$ varies dramatically in different cosmic web environments. At z = 0, we find a characteristic halo mass of $10^{12} h^{-1}\rm M_{\odot}$, below which the stellar-to-halo mass ratio is higher in knots while above which it reverses. This particular halo mass corresponds to a characteristic stellar mass of $1.8\times 10^{10} h^{-1}\rm M_{\odot}$. Below the characteristic stellar mass central galaxies have redder colors, lower sSFRs and higher metallicities in knots than those in filaments, sheets and voids, while above this characteristic stellar mass, the cosmic web environmental dependences either reverse or vanish. Such dependences can be attributed to the fact that the active galaxy fraction decreases along voids, sheets, filaments and knots. The cosmic web dependences get weaker towards higher redshifts for most of the explored galaxy properties and scaling relations, except for the gas metallicity vs. stellar mass relation.