Nuclear starburst activity induced by elongated bulges in spiral galaxies

Eunbin Kim*, Sungsoo S. Kim, Yun-Young Choi, Gwang-Ho Lee, Richard De Grijs, Myung Gyoon Lee, Ho Seong Hwang

*Corresponding author for this work

    Research output: Contribution to journalArticlepeer-review

    5 Citations (Scopus)

    Abstract

    We study the effects of bulge elongation on the star formation activity in the centres of spiral galaxies using the data from the Sloan Digital Sky Survey Data Release 7. We construct a volume-limited sample of face-on spiral galaxies with Mr < -19.5 mag at 0.02 ≤ z ≤ 0.055 by excluding barred galaxies, where the aperture of the SDSS spectroscopic fibre covers the bulges of the galaxies. We adopt the ellipticity of bulges measured by Simard et al., who performed two-dimensional bulge + disc decompositions using the SDSS images of galaxies, and identify nuclear starbursts using the fibre specific star formation rates derived from the SDSS spectra. We find a statistically significant correlation between bulge elongation and nuclear starbursts in the sense that the fraction of nuclear starbursts increases with bulge elongation. This correlation is more prominent for fainter and redder galaxies, which exhibit higher ratios of elongated bulges. We find no significant environmental dependence of the correlation between bulge elongation and nuclear starbursts. These results suggest that nonaxisymmetric bulges can efficiently feed the gas into the centre of galaxies to trigger nuclear starburst activity.

    Original languageEnglish
    Pages (from-to)562-569
    Number of pages8
    JournalMonthly Notices of the Royal Astronomical Society
    Volume479
    Issue number1
    DOIs
    Publication statusPublished - 1 Sep 2018

    Keywords

    • Galaxies bulges
    • Galaxies: evolution
    • Galaxies: formation
    • Galaxies: spiral
    • Galaxies: star formation
    • Galaxies: starburst

    Fingerprint

    Dive into the research topics of 'Nuclear starburst activity induced by elongated bulges in spiral galaxies'. Together they form a unique fingerprint.

    Cite this