The environment of barred galaxies in the low-redshift Universe

TL;DR

This study investigates the environmental factors influencing barred galaxies in the low-redshift universe, revealing weak overall differences but specific trends for early- and late-type galaxies related to their clustering and local surroundings.

Contribution

It provides a comprehensive analysis of the environment of barred galaxies using multiple statistical measures, highlighting the dependence of bar presence on galaxy type and local environment.

Findings

Early-type barred galaxies are more strongly clustered than unbarred ones.

Barred late-type galaxies have fewer close neighbors, suggesting tidal forces affect bar formation.

No significant link between large-scale overdensity and the presence of bars.

Abstract

We present a study of the environment of barred galaxies using a volume-limited sample of over 30,000 galaxies drawn from the Sloan Digital Sky Survey. We use four different statistics to quantify the environment: the projected two-point cross-correlation function, the background-subtracted number count of neighbor galaxies, the overdensity of the local environment, and the membership of our galaxies to galaxy groups to segregate central and satellite systems. For barred galaxies as a whole, we find a very weak difference in all the quantities compared to unbarred galaxies of the control sample. When we split our sample into early- and late-type galaxies, we see a weak but significant trend for early-type galaxies with a bar to be more strongly clustered on scales from a few 100 kpc to 1 Mpc when compared to unbarred early-type galaxies. This indicates that the presence of a bar in early-type galaxies depends on the location within their host dark matter halos. This is confirmed by the group catalog in the sense that for early-types, the fraction of central galaxies is smaller if they have a bar. For late-type galaxies, we find fewer neighbors within $\sim$50 kpc around the barred galaxies when compared to unbarred galaxies form the control sample, suggesting that tidal forces from close companions suppress the formation/growth of bars. Finally, we find no obvious correlation between overdensity and the bars in our sample, showing that galactic bars are not obviously linked to the large-scale structure of the universe.