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Spectroscopic Studies of Very Metal-Poor Stars with the Subaru High Dispersion Spectrograph. III. Light Neutron-Capture Elements

Wako Aoki·Satoshi Honda·Timothy C. Beers·Toshitaka Kajino·Hiroyasu Ando·John E. Norris·Sean G. Ryan·Hideyuki Izumiura·Kozo Sadakane·Masahide Takada-Hidai
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Abstract

Elemental abundance measurements have been obtained for a sample of 18 very metal-poor stars using spectra obtained with the Subaru Telescope High Dispersion Spectrograph. Seventeen stars, among which 16 are newly analyzed in the present work, were selected from candidate metal-poor stars identified in the HK survey of Beers and colleagues. The metallicity range covered by our sample is -3.1 ~< [Fe/H] ~< -2.4. The abundances of carbon, alpha-elements, and iron-peak elements determined for these stars confirm the trends found by previous work. One exception is the large over-abundance of Mg, Al and Sc found in BS16934--002, a giant with [Fe/H] = -2.8. By combining our new results with those of previous studies, we investigate the distribution of neutron-capture elements in very metal-poor stars, focusing on the production of the light neutron-capture elements (e.g., Sr, Y, and Zr).

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Wako Aoki, Satoshi Honda, Timothy C. Beers, Toshitaka Kajino, Hiroyasu Ando, John E. Norris, Sean G. Ryan, Hideyuki Izumiura, Kozo Sadakane, Masahide Takada-Hidai. 2005-06-19. Spectroscopic Studies of Very Metal-Poor Stars with the Subaru High Dispersion Spectrograph. III. Light Neutron-Capture Elements. https://doi.org/10.1086/432862

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