{"paper":{"title":"Non-LTE Analysis for the Sodium Abundances of Metal-Poor Stars in the Galactic Disk and Halo","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"Gang Zhao, Hua-Wei Zhang, Masahide Takada-Hidai, Yoichi Takeda, Yu-ji Saito, Yu-Qin Chen","submitted_at":"2003-04-18T04:58:11Z","abstract_excerpt":"We performed an extensive non-LTE analysis of the neutral sodium lines of Na {\\sc i} 5683/5688, 5890/5896, 6154/6161, and 8183/8195 for disk/halo stars of F--K type covering a wide metallicity range ($-4 \\la$ [Fe/H] $\\la 0.4$), based on our own data as well as those collected from the literature. For comparatively metal-rich disk stars ($-1 \\la$ [Fe/H] $\\la 0$) where the weaker 6154/6161 lines are best abundance indicators, we confirmed [Na/Fe] $\\sim$ 0 with an ``upturn'' (i.e., a shallow/broad dip around $-0.5 \\la$ [Fe/H] $\\la 0$) as already reported by previous studies. Regarding the metal-d"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0304337","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}