New abundances for neutron-capture (n-capture) elements in a large sample of metal-poor giants from the Bond survey are presented. The spectra were acquired with the KPNO 4-m echelle and coudé feed spectrographs, and have been analyzed using LTE fine-analysis techniques with both line analysis and spectral synthesis. Abundances of eight n-capture elements (Sr, Y, Zr, Ba, La, Nd, Eu, Dy) in 43 stars have been derived from blue (λλ4070-4710Å, R∼20,000, S/N ratio∼100-200) echelle spectra and red (λλ6100-6180Å, R∼22,000, S/N ratio∼100-200) coudé spectra, and the abundance of Ba only has been derived from the red spectra for an additional 27 stars.Overall, the abundances show clear evidence for a large star-to-star dispersion in the heavy element-to-iron ratios. This condition must have arisen from individual nucleosynthetic events in rapidly evolving halo progenitors that injected newly manufactured n-capture elements into an inhomogeneous early Galactic halo interstellar medium. The new data also confirm that at metallicities [Fe/H] ∼ <-2.4, the abundance pattern of the heavy (Z≥56) n-capture elements in most giants is well-matched to a scaled Solar System r-process nucleosynthesis pattern.The onset of the main r-process can be seen at [Fe/H]≈-2.9; this onset is consistent with the suggestion that low mass Type II supernovae are responsible for the r-process. Contributions from the s-process can first be seen in some stars with metallicities as low as [Fe/H]∼-2.75, and are present in most stars with metallicities [Fe/H]>-2.3. The appearance of s-process contributions as metallicity increases presumably reflects the longer stellar evolutionary timescale of the (low-mass) s-process nucleosynthesis sites.The lighter n-capture elements (Sr-Y-Zr) are enhanced relative to the heavier r-process element abundances. Their production cannot be attributed solely to any combination of the Solar System r-and main s-processes, but requires a mixture of material from the r-process and from an additional n-capture process which can operate at early Galactic time. This additional process could be the weak s-process in massive (∼25 M ⊙ ) stars, or perhaps a second r-process site, i.e. different than the site that produces the heavier (Z≥56) n-capture elements.
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