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Two distinct halo populations in the solar neighborhood: evidence from stellar abundance of beryllium

Published online by Cambridge University Press:  06 January 2014

Kefeng Tan  and
Gang Zhao
Kefeng Tan
Affiliation:
Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China email: [email protected]; [email protected]
Gang Zhao
Affiliation:
Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China email: [email protected]; [email protected]
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Abstract

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It is now generally believed that the Galaxy was formed through hierarchical merging, which means that different components of the Galaxy may have experienced different chemical evolution histories. Since alpha elements are mainly produced by core collapse supernovae, they are closely associated with the star formation history of the Galaxy. In this regard, Galactic components with different alpha elemental abundance patterns may show different behaviors in beryllium abundances since the production of beryllium is correlated with the cosmic rays and thus the supernovae. A recent study by Nissen & Schuster (2010) has revealed the existence of two distinct halo populations in the solar neighborhood based on the alpha elemental abundances and kinematics of 94 dwarf stars. We determined beryllium abundances for some of these stars and find systematic differences in beryllium abundances between these two halo populations. Our results consolidate the conclusion of two distinct halo populations in the solar neighborhood. Our results also show that beryllium abundance is a very good indicator of star formation rate, and could be used to trace the substructures of the Galactic halo.

Keywords

Galaxy: formationGalaxy: halostars: abundances
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 9 , Symposium S298: Setting the scene for Gaia and LAMOST , May 2013 , pp. 83 - 85
Copyright
Copyright © International Astronomical Union 2014 

References

Duncan, D. K., Primas, F., Rebull, L. M., Boesgaard, A. M., Deliyannis, C. P., Hobbs, L. M., King, J. R., & Ryan, S. G. 1997, ApJ, 488, 338Google Scholar
Nissen, P. E., & Schuster, W. J. 2010, A&A, 511, L10Google Scholar
Ramírez, I., Meléndez, J., & Chanamé, J. 2012, ApJ, 757, 164Google Scholar
Reeves, H., Fowler, W. A., & Hoyle, F. 1970, Nature, 226, 727Google Scholar