The Bulletin of The Korean Astronomical Society (천문학회보)
- Volume 39 Issue 1
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- Pages.38.1-38.1
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- 2014
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- 1226-2692(pISSN)
Nuclear star formation in galaxies due to non-axisymmetric bulges
- Kim, Eunbin (School of Space Research, Kyung Hee University) ;
- Kim, Sungsoo S. (School of Space Research, Kyung Hee University) ;
- Lee, Gwang-Ho (Dept. of Physics and Astronomy, Seoul National University) ;
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Lee, Myung Gyoon
(Dept. of Physics and Astronomy, Seoul National University)
;
- Grijs, Richard De (Kavli Institute for Astronomy & Astrophysics and Dept. of Astronomy, Pecking University) ;
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Choi, Yun-Young
(Dept. of Astronomy & Space Science, Kyung Hee University)
- Published : 2014.04.10
Abstract
A non-axisymmetric mass distribution in the galactic bulge (or bar) causes gas flow from the disk to the nuclear region, inducing intense star formation in the nucleus. We investigate the relation between the ellipticity of the bulge and the presence of a nuclear starburst by using a volume-limited sample of galaxies. We use 1,680 spiral galaxies with Mr < -19.5 at 0.02 <= z < 0.05 in the Sloan Digital Sky Survey Data Release 7. We find that the occurrence of nuclear starburst has a moderate correlation with bulge ellipticity in intermediate-type spiral galaxies (morphology classes Sab~Sb) in low galaxy number density environments. In high galaxy number density environments, close encounters and mergers between galaxies can cause gas inflow to the nuclear region even without the presence of non-axisymmetric bulges.
Keywords