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Copper and Barium Abundances in the Ursa Major Moving Group

S. Castro·G. F. Porto de Mello·L. da Silva
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Abstract

We present Cu and Ba abundances for 7 G-K dwarf stars, members of the solar-metallicity, 0.3 Gyr old Ursa Major Moving Group. All analyzed member stars show [Ba/Fe] excesses of +0.3-plus, associated with [Cu/Fe] deficiencies of up to -0.23 dex. The present results suggest that there is an anti-correlation between the abundances of Cu and the heavy elements produced by the main component of the neutron capture s-process. Other possible anomalies are Na and C deficiencies with respect to normal solar-metallicity stars. The new data do not confirm the recent claim that the group member HR6094 is a Ba dwarf star.

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S. Castro, G. F. Porto de Mello, L. da Silva. 1999-01-15. Copper and Barium Abundances in the Ursa Major Moving Group. https://doi.org/10.1046/j.1365-8711.1999.02455.x

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