{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2000:L6P47MRQ7OYJHDQXGIARFL5PWV","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"705372a8626176d302099bb924e2dbd0a59791e36435850a61748c40f192d3b8","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2000-09-01T19:53:58Z","title_canon_sha256":"44bdccaff6a40ab3991ba1e18a0e2c348fb7c94e6c144ce6756a3d518141dff0"},"schema_version":"1.0","source":{"id":"astro-ph/0009025","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/0009025","created_at":"2026-05-18T02:32:55Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/0009025v1","created_at":"2026-05-18T02:32:55Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/0009025","created_at":"2026-05-18T02:32:55Z"},{"alias_kind":"pith_short_12","alias_value":"L6P47MRQ7OYJ","created_at":"2026-05-18T12:25:50Z"},{"alias_kind":"pith_short_16","alias_value":"L6P47MRQ7OYJHDQX","created_at":"2026-05-18T12:25:50Z"},{"alias_kind":"pith_short_8","alias_value":"L6P47MRQ","created_at":"2026-05-18T12:25:50Z"}],"graph_snapshots":[{"event_id":"sha256:0c56fe0e793de7f3485b3d866f31dec0dfdd0811ceca9cfa9bee771e4362ebb7","target":"graph","created_at":"2026-05-18T02:32:55Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"paper":{"abstract_excerpt":"We present time-resolved optical spectroscopy of the afterglows of the gamma-ray bursts GRB 990510 and GRB 990712. Through the identification of several absorption lines in the first epoch GRB 990510 spectrum, we determine the redshift for this burst at z >= 1.619. No clear emission lines are detected. The strength of the MgI feature is indicative of a dense environment, most likely the host galaxy of GRB 990510. Although the host is extremely faint (V >~ 28), the GRB afterglow allows us to probe its interstellar medium and - in principle - to measure its metallicity. The optical spectrum of G","authors_text":"A. Fruchter, C. Kouveliotou, E. Palazzi, E. Pian, E.P.J. van den Heuvel, E. Rol, F. Frontera, F.V. Hessman, H. Nicklas, J. van Paradijs, K. Beuermann, K. Reinsch, L. Kaper, N. Masetti, P.M. Vreeswijk, R.A.M.J. Wijers, S. Savaglio, T.J. Galama","cross_cats":[],"headline":"","license":"","primary_cat":"astro-ph","submitted_at":"2000-09-01T19:53:58Z","title":"VLT spectroscopy of GRB 990510 and GRB 990712; probing the faint and bright end of the GRB host galaxy population"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0009025","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:38690391da12dc607f07f14a309aea205ed10d10e272cbd82059b41ea2b83d9f","target":"record","created_at":"2026-05-18T02:32:55Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"705372a8626176d302099bb924e2dbd0a59791e36435850a61748c40f192d3b8","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2000-09-01T19:53:58Z","title_canon_sha256":"44bdccaff6a40ab3991ba1e18a0e2c348fb7c94e6c144ce6756a3d518141dff0"},"schema_version":"1.0","source":{"id":"astro-ph/0009025","kind":"arxiv","version":1}},"canonical_sha256":"5f9fcfb230fbb0938e17320112afafb54783c8b2e2fcfab6dce9325e997442c7","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"5f9fcfb230fbb0938e17320112afafb54783c8b2e2fcfab6dce9325e997442c7","first_computed_at":"2026-05-18T02:32:55.488751Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:32:55.488751Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"sohksW5wIxFkjkbH7e1zIxlICfi6kNhGJbKMg2q4frKrjIVq8dP9BmZPA0h7pSenrNj2Dvp+4fMiN1D9S9oGAA==","signature_status":"signed_v1","signed_at":"2026-05-18T02:32:55.489229Z","signed_message":"canonical_sha256_bytes"},"source_id":"astro-ph/0009025","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:38690391da12dc607f07f14a309aea205ed10d10e272cbd82059b41ea2b83d9f","sha256:0c56fe0e793de7f3485b3d866f31dec0dfdd0811ceca9cfa9bee771e4362ebb7"],"state_sha256":"03c25ddac5969c4f57e54faa89df0bc01d13eb5ed0f2e4fd9658ac9e9b7cf499"}