Edge-on galaxies relative to edge-on view of the Local Supercluster

TL;DR

This study investigates the alignment of galaxy spins within the Local Supercluster, finding a weak perpendicular tendency for low-mass galaxies, with no significant correlation observed in other groups.

Contribution

It provides a modern statistical analysis of galaxy spin orientations in the Local Supercluster, improving upon previous studies with updated catalogs and methods.

Findings

Low-mass galaxies tend to have spins perpendicular to the supercluster plane.

No significant alignment found in higher mass or other galaxy subsamples.

The observed alignment is statistically weak, at about 2-sigma level.

Abstract

Cosmological theories suggest that the angular momentum of galaxies should be closely linked to the structure of the cosmic web. The Local Supercluster is the closest and most studied structure where the orientation of galaxy spins can be studied. As noted by Navarro et al. (2004), the use of edge-on galaxies greatly simplifies this task by reducing it to an analysis of the distribution of position angles in the Supergalactic coordinates. We reexamine this correlation using modern catalogs that allow us to perform a more robust statistical analysis. We test the dependence on redshift, spatial position, luminosity, and color. We find that the spins of galaxies with stellar mass $M_*<10^{8.7}$ $M_\odot$ show a weak tendency to be aligned perpendicular to the plane of the Local Supercluster at the 2-sigma level. Other subsamples do not show statistically significant correlations.