{"paper":{"title":"On the use of the index N2 to derive the metallicity in metal-poor galaxie","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"2), 2) ((1) Instituto de Astrofisica de Canarias, (2) Departamento de Astrofisica, (3) Instituto de Astrofisica de Andalucia - CSIC, A.B. Morales-Luis (1, C. Munoz Tunon (1, E. Perez-Montero (3), Granada, J. Sanchez Almeida (1, La Laguna, Spain, Spain), Tenerife, Universidad de La Laguna","submitted_at":"2014-10-10T17:48:19Z","abstract_excerpt":"The N2 index ([N II]6584/Ha) is used to determine emission line galaxy metallicities at all redshifts, including high redshift, where galaxies tend to be metal-poor. The initial aim of the work was to improve the calibrations used to infer oxygen abundance from N2 employing updated low-metallicity galaxy databases. We compare N2 and the metallicity determined using the direct method for the set of extremely metal-poor galaxies compiled by Morales-Luis et al. (2011). To our surprise, the oxygen abundance presents a tendency to be constant with N2, with a very large scatter. Consequently, we fin"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1410.2850","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"}