Nexus of the Cosmic Web

TL;DR

This paper introduces the NEXUS+ formalism, an advanced multiscale method for identifying and characterizing the cosmic web's structures, enabling detailed analysis of environmental effects on dark matter haloes and galaxies.

Contribution

The work presents a novel multiscale, hierarchical algorithm that effectively traces all cosmic web components and characterizes their properties, improving upon previous methods.

Findings

Successful identification of cosmic web structures across scales

Ability to characterize filament and wall properties in detail

Facilitates analysis of environmental influence on haloes

Abstract

One of the important unknowns of current cosmology concerns the effects of the large scale distribution of matter on the formation and evolution of dark matter haloes and galaxies. One main difficulty in answering this question lies in the absence of a robust and natural way of identifying the large scale environments and their characteristics. This work summarizes the NEXUS+ formalism which extends and improves our multiscale scale-space MMF method. The new algorithm is very successful in tracing the Cosmic Web components, mainly due to its novel filtering of the density in logarithmic space. The method, due to its multiscale and hierarchical character, has the advantage of detecting all the cosmic structures, either prominent or tenuous, without preference for a certain size or shape. The resulting filamentary and wall networks can easily be characterized by their direction, thickness, mass density and density profile. These additional environmental properties allows to us to investigate not only the effect of environment on haloes, but also how it correlates with the environment characteristics.