The Imprint of Cosmic Web Quenching on Central Galaxies

TL;DR

This study examines how the cosmic web environment influences the properties of central galaxies, revealing that proximity to web features correlates with lower star formation, older age, and higher metallicity, supporting environmental quenching mechanisms.

Contribution

It provides new evidence that cosmic web features affect galaxy properties independently of local density and mass, highlighting nurture and intrinsic effects in galaxy evolution.

Findings

Galaxies closer to web nodes, walls, or filaments are older and more metal-rich.

Property gradients are consistent across field and group environments.

Cosmic web quenching involves nurture effects like ram pressure stripping and intrinsic web properties.

Abstract

We investigate how cosmic web environment impacts the average properties of central galaxies in the Sloan Digital Sky Survey (SDSS). We analyse how the average specific star-formation rate, stellar age, metallicity and element abundance ratio [$\alpha$/Fe] of SDSS central galaxies depend on distance from the cosmic web nodes, walls and filaments identified by DisPerSE. In our approach we control for galaxy stellar mass and local density differentiated between field and group environment. Our results confirm the known trend whereby galaxies exhibit lower specific star-formation rates with decreasing distance to the cosmic web features. Furthermore, we show that centrals closer to either nodes, walls or filaments are on average older, metal richer and $\alpha$-enhanced compared to their equal mass counterparts at larger distances. The identified property gradients appear to have the same amplitude for central galaxies in the field as for those in groups. Our findings support a cosmic web quenching that stems from nurture effects, such as ram pressure stripping and strangulation, and/or nature effects linked to the intrinsic properties of the cosmic web.