Nuclear starburst activity induced by elongated bulges in spiral galaxies
Affiliation
Univ Arizona, Steward ObservIssue Date
2018-06-05Keywords
galaxies: bulges galaxies: evolutiongalaxies: formation
galaxies: spiral
galaxies: starburst
galaxies: star formation
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OXFORD UNIV PRESSCitation
Eunbin Kim, Sungsoo S Kim, Yun-Young Choi, Gwang-Ho Lee, Richard de Grijs, Myung Gyoon Lee, Ho Seong Hwang, Nuclear starburst activity induced by elongated bulges in spiral galaxies, Monthly Notices of the Royal Astronomical Society, Volume 479, Issue 1, September 2018, Pages 562–569, https://doi.org/10.1093/mnras/sty1451Rights
Copyright © 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.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 non-axisymmetric bulges can efficiently feed the gas into the centre of galaxies to trigger nuclear starburst activity.ISSN
0035-8711Version
Final published versionSponsors
National Research Foundation -Ministry of Science, ICT and Future Planning of Korea [NRF-2014R1A2A1A11052367]; KASI-Arizona Fellowship; National Natural Science Foundation of China [U1631102, 11373010, 11633005]; National Key Research and Development Program of China [2017YFA0402702]; National Research Foundation (NRF) of Korea - Korean Government [NRF-2017R1A2B4004632]; National Research Foundation of Korea [2017R1A5A1070354]; Alfred P. Sloan Foundation; National Science Foundation; U.S. Department of Energy; National Aeronautics and Space Administration; Japanese Monbukagakusho; Max Planck Society; Higher Education Funding Council for England; American Museum of Natural History; Astrophysical Institute Potsdam; University of Basel; University of Cambridge; Case Western Reserve University; University of Chicago; Drexel University; Fermilab; Institute for Advanced Study; Japan Participation Group; Johns Hopkins University; Joint Institute for Nuclear Astrophysics; Kavli Institute for Particle Astrophysics and Cosmology; Korean Scientist Group; Chinese Academy of Sciences (LAMOST); Los Alamos National Laboratory; Max-Planck-Institute for Astronomy (MPIA); Max-Planck-Institute for Astrophysics (MPA); New Mexico State University; Ohio State University; University of Pittsburgh; University of Portsmouth; Princeton University; United States Naval Observatory; University of WashingtonScopus Count
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