{"paper":{"title":"The optically unbiased GRB host (TOUGH) survey. V. VLT/X-shooter emission-line redshifts for Swift GRBs at z~2","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"Andrew J. Levan, Bo Milvang-Jensen, Daniele Malesani, Darach J. Watson, Jens Hjorth, Johan P. U. Fynbo, Martin Sparre, Nial R. Tanvir, P\\'all Jakobsson, Thomas Kr\\\"uhler","submitted_at":"2012-05-17T20:01:48Z","abstract_excerpt":"We present simultaneous optical and near-infrared (NIR) spectroscopy of 19 Swift GRB host galaxies with VLT/X-shooter with the aim of measuring their redshifts. Galaxies were selected from The Optically Unbiased GRB Host (TOUGH) survey (15 of the 19 galaxies) or because they hosted GRBs without a bright optical afterglow. Here, we provide emission-line redshifts for 13 of the observed galaxies with brightnesses between F606W > 27 mag and R=22.9 mag (median R=24.6 mag). The median redshift is z=2.1 for all, and z=2.3 for the TOUGH hosts. Our new data significantly improve the redshift completen"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1205.4036","kind":"arxiv","version":2},"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"}