R. Sánchez-Janssen, D. Gadotti
We address the effects of bar-driven secular evolution in discs by comparing their properties in a sample of nearly 700 unbarred and barred (42 +- 3 per cent of the population) massive disc galaxies (Mstar > 10^10 Msun). We make use of accurate structural parameters derived from bulge/disc/bar decompositions to show that, as a population, barred discs tend to have fainter central surface brightness (\Delta\mu\ ~ 0.25 mag in the i-band), and disc scale lengths that are larger by a factor ~1.15 than those of unbarred galaxies. The corresponding distributions of \mu\ and h are statistically inconsistent at the 5.2\sigma\ and 3.8\sigma\ levels, respectively. Bars rarely occur in high-surface brightness discs, with less than 5 per cent of the barred population having \mu\ < 19.5 mag/arcsec^2 -- compared to 20 per cent for unbarred galaxies. They tend to reside in moderately blue discs, with a bar fraction that peaks at (g-i) ~ 0.95 mag and mildly declines for both bluer and redder colours. These results demonstrate that bars induce noticeable evolution in the structural properties of galaxy discs, in qualitative agreement with longstanding theoretical expectations.
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http://arxiv.org/abs/1208.3682
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