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An overall picture of EMP stars using the stellar abundances for galactic archaeology (SAGA) database

Published online by Cambridge University Press:  09 March 2010

Takuma Suda
Affiliation:
Astrophysics Group, EPSAM, Keele University, Keele, Staffordshire, ST5 5BG, UK email: suda@astro.keele.ac.uk, chikako@astro.keele.ac.uk
Shimako Yamada
Affiliation:
Dept. of Cosmosciences, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo, 060-0810, Japan email: yamada@astro1.sci.hokudai.ac.jp, kat@astro1.sci.hokudai.ac.jp, fujimoto@astro1.sci.hokudai.ac.jp
Yutaka Katsuta
Affiliation:
Dept. of Cosmosciences, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo, 060-0810, Japan email: yamada@astro1.sci.hokudai.ac.jp, kat@astro1.sci.hokudai.ac.jp, fujimoto@astro1.sci.hokudai.ac.jp
Chikako Ishizuka
Affiliation:
Astrophysics Group, EPSAM, Keele University, Keele, Staffordshire, ST5 5BG, UK email: suda@astro.keele.ac.uk, chikako@astro.keele.ac.uk
Yutaka Komiya
Affiliation:
National Astronomical Observatory of Japan, 2-1-21, Osawa, Mitaka, Tokyo, 181-8588, Japan email: yutaka.komiya@nao.ac.jp, nishimura.takanori@nao.ac.jp, aoki.wako@nao.ac.jp
Takanori Nishimura
Affiliation:
National Astronomical Observatory of Japan, 2-1-21, Osawa, Mitaka, Tokyo, 181-8588, Japan email: yutaka.komiya@nao.ac.jp, nishimura.takanori@nao.ac.jp, aoki.wako@nao.ac.jp
Wako Aoki
Affiliation:
National Astronomical Observatory of Japan, 2-1-21, Osawa, Mitaka, Tokyo, 181-8588, Japan email: yutaka.komiya@nao.ac.jp, nishimura.takanori@nao.ac.jp, aoki.wako@nao.ac.jp
Masayuki Y. Fujimoto
Affiliation:
Dept. of Cosmosciences, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo, 060-0810, Japan email: yamada@astro1.sci.hokudai.ac.jp, kat@astro1.sci.hokudai.ac.jp, fujimoto@astro1.sci.hokudai.ac.jp
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Abstract

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We explore the general characteristics of extremely metal-poor (EMP) stars in the Galaxy using the Stellar Abundances for Galactic Archaeology (SAGA) database (Suda et al. 2008, PASJ, 60, 1159). The overall trend of EMP stars suggests that there are at least two types of extra mixing to change the surface abundances of EMP stars. One is to deplete lithium abundance during the early phase of giant branch and another is to decrease C/N ratio by one order of magnitude during the red giant branch or AGB phase. On the other hand, these mixing processes are different from those suggested in the Galactic globular clusters because of the different relations between O, Na, Mg, and Al abundances.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2010

References

Aoki, W., Beers, T. C., Christlieb, N., Norris, J. E., Ryan, S. G., & Tsangarides, S., 2007, ApJ, 655, 492CrossRefGoogle Scholar
Deliyannis, C. P., Demarque, P., & Kawaler, S. D. 1990, ApJS, 73, 21CrossRefGoogle Scholar
Fujimoto, M. Y., Ikeda, Y., & Iben, I. Jr. 2000, ApJ, 529, L25CrossRefGoogle Scholar
Gratton, R. G., Sneden, C., Carretta, E., & Bragaglia, A. 2000, A&A, 354, 169Google Scholar
Komiya, Y., Suda, T., Minaguchi, H., Shigeyama, T., Aoki, W., & Fujimoto, M. Y. 2007, ApJ, 658, 367CrossRefGoogle Scholar
Nishimura, T., Aikawa, M., Suda, T., & Fujimoto, M. Y. 2009, PASJ, 61, 909CrossRefGoogle Scholar
Spite, M., Cayrel, R., Plez, B., Hill, V., Spite, F., Depagne, E., François, P., Bonifacio, P., Barbuy, B., Beers, T., Andersen, J., Molaro, P., Nordström, B., & Primas, F. 2005, A&A, 430, 655Google Scholar
Suda, T., Aikawa, M., Machida, M. N., Fujimoto, M. Y., & Iben, I. Jr. 2004, ApJ, 611, 476CrossRefGoogle Scholar
Suda, T. & Fujimoto, M. Y. 2009, MNRAS, accepted, ArXiv 1002, 0863Google Scholar
Suda, T., Katsuta, Y., Yamada, S., Suwa, T., Ishizuka, C., Komiya, Y., Sorai, K., Aikawa, M., & Fujimoto, M. Y. 2008, PASJ, 60, 1159CrossRefGoogle Scholar