Star formation activity of barred spiral galaxies

TL;DR

This study investigates how the presence and strength of bars in spiral galaxies influence their star formation activity, gas content, and metallicity, revealing that strongly barred galaxies have lower current star formation and gas than non-barred ones, with past activity affected by bar strength.

Contribution

It provides a comparative analysis of star formation and gas properties in strongly and weakly barred versus non-barred galaxies, highlighting the impact of bar strength on galaxy evolution.

Findings

Strongly barred galaxies have lower star formation activity than non-barred galaxies.

Strongly barred galaxies possess less atomic and molecular gas and higher metallicity.

Weakly barred galaxies show no significant difference from non-barred galaxies.

Abstract

We study the star formation activity of nearby galaxies with bars using a sample of late-type galaxies at 0.02$\leq z \leq$ 0.05489 and $M_r <-19.5$ from the Sloan Digital Sky Survey. We compare the physical properties of strongly and weakly barred galaxies with those of non-barred galaxies that have stellar mass and redshift distributions similar to barred galaxies. We find that the star formation activity of strongly barred galaxies probed by starburstiness, $\it{g-r}$, NUV$-r$, and mid-infrared [3.4]$-$[12] colors is, on average, lower than that of non-barred galaxies. However, weakly barred galaxies do not show such a difference between barred and non-barred galaxies. The amounts of atomic and molecular gas in strongly barred galaxies are smaller than those of non-barred galaxies, and the gas metallicity is higher in strongly barred galaxies than in non-barred galaxies. The gas properties of weakly barred galaxies again show no difference from those of non-barred galaxies. We stack the optical spectra of barred and non-barred galaxies in several mass bins and fit to the stacked spectra with a spectral fitting code, STARLIGHT. We find no significant difference in stellar populations between barred and non-barred galaxies for both strongly and weakly barred galaxies. Our results are consistent with the idea that the star formation activity of barred galaxies is enhanced in the past along with significant gas consumption, and is currently lower than or similar to that of non-barred galaxies. The past star formation enhancement depends on the strength of bars.