{"paper":{"title":"The Broken Light Curves of Gamma-Ray Bursts GRB 990123 and GRB 990510","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"(2) University of Iceland, (3) University of Copenhagen), B. Thomsen (1) ((1) University of Aarhus, G. Bjornsson (2), J. Hjorth (3), S. Holland (1)","submitted_at":"2000-10-10T16:55:25Z","abstract_excerpt":"We have collected all of the published photometry for GRB 990123 and GRB 990510, the first two gamma-ray bursts where breaks were seen in the light curves of their optical afterglows, and determined the shapes of their light curves and the break times. These parameters were used to investigate the physical mechanisms responsible for the breaks and the nature of the ambient medium that the bursts occurred in. The light curve for GRB 990123 is best fit by a broken power law with a break 1.68 +/- 0.19 days after the burst, a slope of alpha1 = -1.12 +/- 0.08 before the break, and a slope of alpha2"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0010196","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"}