Relative effect of nodes and filaments of the cosmic web on the quenching of galaxies and the orientation of their spin

Université Paris-Saclay, CNRS, Institut d’Astrophysique Spatiale, 91405 Orsay, France
e-mail: nmalavas@ias.u-psud.fr

Received: 6 July 2021
Accepted: 9 November 2021

Abstract

Filaments and clusters of the cosmic web have an impact on the properties of galaxies. They switch off their star-formation, contribute to the build-up of their stellar mass, and affect the acquisition of their angular momentum. We make use of the IllustrisTNG simulation, coupled with the DisPerSE cosmic web extraction algorithm, to test which galaxy property is most affected by the cosmic web and, conversely, to assess the differential impact of the various cosmic web features on a given galaxy property. Our aim is to use this information to better understand galaxy evolution and to identify on which galaxy property future efforts should focus to detect the cosmic web from the galaxy distribution. We provide a comprehensive analysis of the relation between galaxy properties and cosmic web features. We also perform extensive tests in which we try to separate the effect of local overdensities of galaxies on their properties from the effect of the large-scale structure environment. Our results show that star formation shows the strongest variation with distance from the cosmic web features, but it also shows the strongest relation to the local environment of galaxies. On the other hand, the direction of the angular momentum of galaxies shows the weakest trends with distance from cosmic web features while also being more independent from the local environment of galaxies. We conclude that the direction of the angular momentum of galaxies and its use to improve our detection of the cosmic web features could be the focus of future studies that will benefit from larger statistical samples.