{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:1999:MV2VRPEGY3SJVXQXOUV5E5UVON","short_pith_number":"pith:MV2VRPEG","schema_version":"1.0","canonical_sha256":"657558bc86c6e49ade17752bd27695737738d74fafb3aaf162594db61898e140","source":{"kind":"arxiv","id":"astro-ph/9906346","version":1},"attestation_state":"computed","paper":{"title":"The discovery of polarization in the afterglow of GRB 990510 with the ESO Very Large Telescope","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"C. Kouveliotou (USRA, E. Palazzi, E. Pian (TESRE), E. Rol (Univ. of Amsterdam), F. Frontera (TESRE, J. van Paradijs (Univ. of Amsterdam, L. Nicastro (IFCAI), L. Piro (IAS, NASA/MSFC), N. Masetti, P.M. Vreeswijk, P. Soffitta, R.A.M.J. Wijers (SUNY Stony Brook), R. Falomo (Padova), Roma), T. Giblin (UAH), T.J. Galama, UAH), Univ. of Ferrara)","submitted_at":"1999-06-22T12:57:17Z","abstract_excerpt":"Following a BeppoSAX alert (Piro 1999a) and the discovery of the OT at SAAO (Vreeswijk et al. 1999a), we observed GRB 990510 with the FORS instrument on ESO's VLT Unit 1 (`Antu'). The burst is unremarkable in gamma rays, but in optical is the first one to show good evidence for jet-like outflow (Stanek et al. 1999, Harrison et al. 1999). We report the detection of significant linear polarization in the afterglow: it is (1.6 +/- 0.2)% 0.86 days after trigger, and after 1.81 days is consistent with that same value, but much more uncertain. The polarization angle is constant on a time scale of ho"},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"astro-ph/9906346","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"1999-06-22T12:57:17Z","cross_cats_sorted":[],"title_canon_sha256":"c22b06ff353f06f02922910f9102a7cd341640befac832bbe725eea3de9530f4","abstract_canon_sha256":"bba9ece12b1e09084a34e4f67475bcbb1031ce29e3abd95cfdcac068739f0130"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-04T16:11:20.694259Z","signature_b64":"UQDnSVTwg7WaKJ9BNu6FpJZF+DwjaCB225tvnOsKAhTTsYeVTBlXZ3RbzwCbY0ZInejIY6bzvL7iJ66KKziEAg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"657558bc86c6e49ade17752bd27695737738d74fafb3aaf162594db61898e140","last_reissued_at":"2026-07-04T16:11:20.693784Z","signature_status":"signed_v1","first_computed_at":"2026-07-04T16:11:20.693784Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"The discovery of polarization in the afterglow of GRB 990510 with the ESO Very Large Telescope","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"C. Kouveliotou (USRA, E. Palazzi, E. Pian (TESRE), E. Rol (Univ. of Amsterdam), F. Frontera (TESRE, J. van Paradijs (Univ. of Amsterdam, L. Nicastro (IFCAI), L. Piro (IAS, NASA/MSFC), N. Masetti, P.M. Vreeswijk, P. Soffitta, R.A.M.J. Wijers (SUNY Stony Brook), R. Falomo (Padova), Roma), T. Giblin (UAH), T.J. Galama, UAH), Univ. of Ferrara)","submitted_at":"1999-06-22T12:57:17Z","abstract_excerpt":"Following a BeppoSAX alert (Piro 1999a) and the discovery of the OT at SAAO (Vreeswijk et al. 1999a), we observed GRB 990510 with the FORS instrument on ESO's VLT Unit 1 (`Antu'). The burst is unremarkable in gamma rays, but in optical is the first one to show good evidence for jet-like outflow (Stanek et al. 1999, Harrison et al. 1999). We report the detection of significant linear polarization in the afterglow: it is (1.6 +/- 0.2)% 0.86 days after trigger, and after 1.81 days is consistent with that same value, but much more uncertain. The polarization angle is constant on a time scale of ho"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/9906346","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/astro-ph/9906346/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"},"aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/9906346","created_at":"2026-07-04T16:11:20.693849+00:00"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/9906346v1","created_at":"2026-07-04T16:11:20.693849+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/9906346","created_at":"2026-07-04T16:11:20.693849+00:00"},{"alias_kind":"pith_short_12","alias_value":"MV2VRPEGY3SJ","created_at":"2026-07-04T16:11:20.693849+00:00"},{"alias_kind":"pith_short_16","alias_value":"MV2VRPEGY3SJVXQX","created_at":"2026-07-04T16:11:20.693849+00:00"},{"alias_kind":"pith_short_8","alias_value":"MV2VRPEG","created_at":"2026-07-04T16:11:20.693849+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/MV2VRPEGY3SJVXQXOUV5E5UVON","json":"https://pith.science/pith/MV2VRPEGY3SJVXQXOUV5E5UVON.json","graph_json":"https://pith.science/api/pith-number/MV2VRPEGY3SJVXQXOUV5E5UVON/graph.json","events_json":"https://pith.science/api/pith-number/MV2VRPEGY3SJVXQXOUV5E5UVON/events.json","paper":"https://pith.science/paper/MV2VRPEG"},"agent_actions":{"view_html":"https://pith.science/pith/MV2VRPEGY3SJVXQXOUV5E5UVON","download_json":"https://pith.science/pith/MV2VRPEGY3SJVXQXOUV5E5UVON.json","view_paper":"https://pith.science/paper/MV2VRPEG","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=astro-ph/9906346&json=true","fetch_graph":"https://pith.science/api/pith-number/MV2VRPEGY3SJVXQXOUV5E5UVON/graph.json","fetch_events":"https://pith.science/api/pith-number/MV2VRPEGY3SJVXQXOUV5E5UVON/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/MV2VRPEGY3SJVXQXOUV5E5UVON/action/timestamp_anchor","attest_storage":"https://pith.science/pith/MV2VRPEGY3SJVXQXOUV5E5UVON/action/storage_attestation","attest_author":"https://pith.science/pith/MV2VRPEGY3SJVXQXOUV5E5UVON/action/author_attestation","sign_citation":"https://pith.science/pith/MV2VRPEGY3SJVXQXOUV5E5UVON/action/citation_signature","submit_replication":"https://pith.science/pith/MV2VRPEGY3SJVXQXOUV5E5UVON/action/replication_record"}},"created_at":"2026-07-04T16:11:20.693849+00:00","updated_at":"2026-07-04T16:11:20.693849+00:00"}