{"paper":{"title":"A spectroscopic study of component C and the extended emission around I Zw 18","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"(2) W. M. Keck Observatory, (3) MMT Observatory, (4) University of Virginia, (5) National Optical Astronomy Observatories, (6) Universit\\\"ats--Sternwarte, C. B. Foltz (3), F. H. Chaffee (2), Germany), G\\\"ottingen, K. J. Fricke (6), Kyiv, N. G. Guseva (1) ((1) Main Astronomical Observatory, P. Papaderos (6), R. F. Green (5), T. X. Thuan (4), Ukraine, University of Arizona, USA, Y. I. Izotov (1)","submitted_at":"2001-09-17T09:50:56Z","abstract_excerpt":"Long-slit Keck II, 4m Kitt Peak, and 4.5m MMT spectrophotometric data are used to investigate the stellar population and the evolutionary status of I Zw 18C, the faint C component of the nearby blue compact dwarf galaxy I Zw 18. Hydrogen H$\\alpha$ and H$\\beta$ emission lines are detected in the spectra of I Zw 18C, implying that ionizing massive stars are present. High signal-to-noise Keck II spectra of different regions in I Zw 18C reveal H$\\gamma$, H$\\delta$ and higher order hydrogen lines in absorption. Several techniques are used to constrain the age of the stellar population in I Zw 18C. "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0109257","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"}