{"paper":{"title":"Discovery of the Optical Transient of the Gamma Ray Burst 990308","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"A. Bongiovanni, A. Dubuc, A. Levine, A. Oemler, A. Rengstorf, B. Adams, Bradley E. Schaefer, B. Roscherr, C. Abad, C. Bailyn, C. Baltay, C. Briceno, C. Kouveliotou, C. Meegan, C. Sabbey et al, D. Band, D. Frail, D. Hartmann, D. Herrera, D. Smith, F. Della Prugna, F. Fuenmayor, F. Harris, G. Bruzual, G. Magris, G. Paredes, G. Williams, H. Park, I. Ferrin, J. A. Snyder, J. Bloom, J. Hernandez, J. Mateu, J. Musser, K. Honeycutt, K. Hurley, L. Romero, M. Deng, M. Gebhard, M. Rengel, N. Ellmann, O. Naranjo, P. Andrews, P. Butterworth, P. Coppi, P. Rosenzweig, R. Bionta, R. Kippen, R. Pacheco, R. Porrata, S. Barthelmy, S. Djorgovski, S. Kulkarni, s. Muffson, T. Cline, W. Emmet","submitted_at":"1999-07-16T21:51:15Z","abstract_excerpt":"The optical transient of the faint Gamma Ray Burst 990308 was detected by the QUEST camera on the Venezuelan 1-m Schmidt telescope starting 3.28 hours after the burst. Our photometry gives $V = 18.32 \\pm 0.07$, $R = 18.14 \\pm 0.06$, $B = 18.65 \\pm 0.23$, and $R = 18.22 \\pm 0.05$ for times ranging from 3.28 to 3.47 hours after the burst. The colors correspond to a spectral slope of close to $f_{\\nu} \\propto \\nu^{1/3}$. Within the standard synchrotron fireball model, this requires that the external medium be less dense than $10^{4} cm^{-3}$, the electrons contain $> 20%$ of the shock energy, and"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/9907235","kind":"arxiv","version":3},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/astro-ph/9907235/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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"}