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Carbon-Enhanced Metal-Poor (CEMP) stars

Published online by Cambridge University Press:  09 March 2010

Wako Aoki*
Affiliation:
National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan email: [email protected]
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Abstract

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A significant fraction of metal-poor stars have large over-abundances of carbon, and are called Carbon-Enhanced Metal-Poor (CEMP) stars. Most of CEMP stars also show excesses of heavy neutron-capture elements like Ba, indicating that their origin is the nucleosynthesis in AGB stars. Remaining CEMP stars that have Ba abundances as low as non-carbon-rich stars appear in the lowest metallicity range ([Fe/H]≲−2.5), and connections with the two most iron-deficient stars (so-called Hyper Metal-Poor stars) are suggested. Although the origins of the carbon-excesses in these objects have not been well identified, some objects suggest contributions of faint supernovae. Remaining problems on CEMP stars, such as the binary fraction, excess of r-process elements, are discussed.

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
Aoki, W., Norris, J. E., Ryan, S. G., Beers, T. C., & Ando, H. 2002, ApJ, 576, L141CrossRefGoogle Scholar
Beers, T. C. & Christlieb, N. 2005, ARAA, 43, 531CrossRefGoogle Scholar
Beers, T. C., Preston, G. W., & Shectman, S. A. 1992, AJ, 103, 1987CrossRefGoogle Scholar
Bond, H. E. 1974, ApJ, 194, 95CrossRefGoogle Scholar
Christlieb, N., et al. 2002, Nature, 419, 904CrossRefGoogle Scholar
Cohen, J. G., et al. 2006, AJ, 132, 137CrossRefGoogle Scholar
Keenan, P. C. 1942, ApJ, 96, 101CrossRefGoogle Scholar
Frebel, A., et al. 2005, Nature, 434, 871CrossRefGoogle Scholar
Frebel, A., et al. 2006, ApJ, 652, 1585CrossRefGoogle Scholar
Ito, H., Aoki, W., Honda, S., & Beers, T. C. 2009, ApJ, 698, L37CrossRefGoogle Scholar
Iwamoto, N., Kajino, T., Mathews, G. J., Fujimoto, M. Y., & Aoki, W. 2004, ApJ, 602, 377CrossRefGoogle Scholar
Lucatello, S., Beers, T. C., Christlieb, N., Barklem, P. S., Rossi, S., Marsteller, B., Sivarani, T., & Lee, Y., ApJ, 625, 825CrossRefGoogle Scholar
Marsteller, B. E., Beers, T. C., Sivarani, T., Rossi, S., Knapp, J., Plez, B., Johnson, J., & Masseron, T. 2006, Bulletin of the American Astronomical Society, 38, 1229Google Scholar
Masseron, T., Johnson, J. A., Plez, B., Van Eck, S., Primas, F., Goriely, S., & Jorissen, A. 2009, arXiv:0901.4737Google Scholar
McClure, R. D. 1984, ApJ, 280, L31CrossRefGoogle Scholar
McWilliam, A., Preston, G. W., Sneden, C., & Searle, L. 1995, AJ, 109, 2757CrossRefGoogle Scholar
Meynet, G., Ekström, S., & Maeder, A. 2006, A&A, 447, 623Google Scholar
Preston, G. W. & Sneden, C. 2001, AJ, 122, 1545CrossRefGoogle Scholar
Ryan, S. G., Aoki, W., Norris, J. E., & Beers, T. C. 2005, ApJ, 635, 349CrossRefGoogle Scholar
Umeda, H. & Nomoto, K. 2003, ApJ, 422, 871Google Scholar
Ventura, P., D'Antona, F., & Mazzitelli, I. 2002, A&A, 393, 215Google Scholar