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Evidence of outflow from the Galactic bulge imprinted in stellar elemental abundances

Published online by Cambridge University Press:  01 July 2007

Takuji Tsujimoto*
Affiliation:
National Astronomical Observatory, Mitaka-shi, Tokyo 181-8588, Japan email: taku.tsujimoto@nao.ac.jp
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Abstract

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We explore the elemental abundance features of metal-rich disk stars, highlighting the comparisons made with those of the recently revealed Galactic bulge stars. A similarity between two of the comparisons leads to a new theoretical picture of the bulge-disk connection in the Galaxy, where a supermassive black hole resides at the center. We postulate that a metal-rich outflow, triggered by feedback from a black hole, was generated and quenched the star formation, which had lasted several billion years in the bulge. The expelled gas cooled down in the Galactic halo without escaping from the gravitational potential of the Galaxy. The gas gradually started to accrete to the disk around five billion years ago, corresponding to the time of sun's birth, and replaced a low-metallicity halo gas that had been accreting over nearly ten billion years. The metal-rich infalling gas, whose elemental abundance reflects that of metal-rich bulge stars, mixed with the interstellar gas already present in the disk. Stars formed from the mixture compose the metal-rich stellar disk.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2008

References

Bensby, T., Feltzing, S., Lundström, I., & Ilyiin, I. 2005, A&A 433, 185Google Scholar
Feltzing, S. & Gustafsson, B. 1998, A&AS 129, 237Google Scholar
Fulbright, J. P., McWilliam, A., & Rich, R. M. 2007, ApJ 661, 1152Google Scholar
Genzel, R., Eckart, A., Ott, T., & Eisenhauer, F. 1997, MNRAS 291, 219CrossRefGoogle Scholar
McWilliam, A., Rich, R. M., & Smecker-Hane, T. A. 2003, ApJ (Letters) 592, L21CrossRefGoogle Scholar
Reddy, B. E., Tomkin, J., Lambert, D. L., & Allende Prieto, C. 2003, MNRAS 340, 304CrossRefGoogle Scholar
Schödel, R., Ott, T., Genzel, R., Eckart, A., Mouawad, N., & Alexander, T. 2003, ApJ 596, 1015CrossRefGoogle Scholar
Silk, J. & Rees, M. J. 1998, A&A (Letters) 331, L1Google Scholar
Springel, V., Di Matteo, T., & Hernquist, L. 2005, MNRAS 361, 776CrossRefGoogle Scholar
Tsujimoto, T. 2007, ApJ (Letters) 665, L115Google Scholar