The environment of barred galaxies in the low-redshift Universe
  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.
