The spatial distribution of dwarf and giant galaxies in and around Virgo cluster

TL;DR

This study investigates how the proportion of dwarf to giant galaxies varies spatially within and around the Virgo cluster, revealing significant local differences influenced by environment and structure.

Contribution

It provides a detailed analysis of dwarf fraction variations across different regions and environments surrounding the Virgo cluster, highlighting local environmental effects.

Findings

Total dwarf fraction within Virgo is approximately 0.8.

Regions further from the cluster have higher dwarf fractions, up to 1.0.

Dwarf fraction is slightly higher in filaments than in the cluster core.

Abstract

The Virgo cluster is one of the closest clusters to us where we can further study the evolution of galaxies, with several infalling substructures and several filaments around it have been reported. Therefore, it makes this cluster and its surrounding an interesting place to study the spatial distribution of the population of dwarf and bright giant galaxies. We analyse the dwarf fraction (DF) in different regions of the cluster, inside the virial radius, in its surrounding area, and in the filamentary structure surrounding it using available catalogues with the aim of measuring whether the DF changes in different environments. Although the total dwarf fraction within the cluster is $\sim$ 0.8, significant local variations are measured throughout the cluster; there are regions with a relatively higher concentration of giant or dwarf galaxies. The fact that Virgo is embedded in a rich environment surrounded by several filaments that feed the cluster with new substructures could imply changes in the DF locally. When we analyse the DF variation at further distances from the cluster we observe some regions with few or no giant galaxies at all, with a locally DF ranging from 0.8 - 1.0. Additionally, when comparing the dwarf fraction in different environments, overall, the DF is larger in regions further away from denser regions such as the Virgo cluster and its filamentary structure surrounding it. When comparing the filament and the cluster area, the dwarf fraction is slightly higher in the filaments, but from filament to filament, the DF changes depending on the presence of groups.