Hunting for low-surface brightness features in nearby galaxy groups

TL;DR

This paper investigates the distribution and motion of dwarf galaxies in nearby galaxy groups, revealing planar and co-rotating structures that challenge current cosmological models, and introduces a method to improve dwarf galaxy census.

Contribution

It demonstrates the presence of co-rotating planar dwarf galaxy structures in the Centaurus group and develops a new approach combining MTO detection with surface brightness fluctuation measurements.

Findings

Evidence for co-rotation within a planar structure of dwarf galaxies in the Centaurus group.

Validation of MTO combined with surface brightness fluctuation distances for dwarf galaxy detection.

Enhanced census of dwarf galaxies in nearby groups for statistical analysis.

Abstract

On the scale of dwarf galaxies, several tensions between observations and the theory of structure formation have been identified in the Local Group of galaxies. One of them, the plane-of-satellite problem describes the distribution and motion of dwarf galaxies around their hosts being planar and co-moving. To extend these studies, we have surveyed the nearby Centaurus group and found again evidence for co-rotation within a planar structure of dwarf galaxies, posing a challenge to the current LambdaCDM paradigm. To further study the distribution of satellite systems around other galaxy groups, we have tested MTO - a program to detect astronomical sources - and found that it works well in combination with surface brightness fluctuation distance measurements to get a complete sample of dwarf galaxies. Such an approach will improve the census of dwarf galaxies in nearby galaxy groups, bringing the study of the small-scale problems to a solid statistical foundation.