{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2007:DZ2OJ6XNBMGA5UERITBSHCDKBI","short_pith_number":"pith:DZ2OJ6XN","schema_version":"1.0","canonical_sha256":"1e74e4faed0b0c0ed09144c323886a0a0c57a2b90a5bba34b8670370b7e11b27","source":{"kind":"arxiv","id":"0712.1831","version":1},"attestation_state":"computed","paper":{"title":"Quasar Broad Absorption Line Variability on Multi-Year Time Scales","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"Donald P. Schneider, Robert R. Gibson, S. C. Gallagher, W. N. Brandt","submitted_at":"2007-12-11T21:22:39Z","abstract_excerpt":"We use quantitative metrics to characterize the variation of CIV 1549 A broad absorption lines (BALs) over 3--6 (rest-frame) years in a sample of 13 quasars at 1.7 <= z <= 2.8 and compare the results to previous studies of BAL variability on shorter time scales. The strong BALs in our study change in complex ways over 3--6 yr. Variation occurs in discrete regions which are only a few thousand km/s wide, and the distribution of the change in absorption equivalent width broadens over time. We constrain the typical CIV BAL lifetime to be at least a few decades. While we do not find evidence to su"},"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":"0712.1831","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"2007-12-11T21:22:39Z","cross_cats_sorted":[],"title_canon_sha256":"00518eb1d96ed6586765527de06808aec48ff346c78fd6f1afde98c12bac30d8","abstract_canon_sha256":"f7f21bc7ee19ee7f1aa8409ec8af69d492909611c5a78869534a513b55760af5"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-04T17:07:12.664800Z","signature_b64":"6CbEfMPslCS23tBHWJstTgWc+plS2LxhB25Jxx33jaskyeK0S78cdSRQ27t510j0tqcss+HPqA1gXHteyT/iDA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"1e74e4faed0b0c0ed09144c323886a0a0c57a2b90a5bba34b8670370b7e11b27","last_reissued_at":"2026-07-04T17:07:12.664391Z","signature_status":"signed_v1","first_computed_at":"2026-07-04T17:07:12.664391Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Quasar Broad Absorption Line Variability on Multi-Year Time Scales","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"Donald P. Schneider, Robert R. Gibson, S. C. Gallagher, W. N. Brandt","submitted_at":"2007-12-11T21:22:39Z","abstract_excerpt":"We use quantitative metrics to characterize the variation of CIV 1549 A broad absorption lines (BALs) over 3--6 (rest-frame) years in a sample of 13 quasars at 1.7 <= z <= 2.8 and compare the results to previous studies of BAL variability on shorter time scales. The strong BALs in our study change in complex ways over 3--6 yr. Variation occurs in discrete regions which are only a few thousand km/s wide, and the distribution of the change in absorption equivalent width broadens over time. We constrain the typical CIV BAL lifetime to be at least a few decades. While we do not find evidence to su"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0712.1831","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/0712.1831/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":"0712.1831","created_at":"2026-07-04T17:07:12.664446+00:00"},{"alias_kind":"arxiv_version","alias_value":"0712.1831v1","created_at":"2026-07-04T17:07:12.664446+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0712.1831","created_at":"2026-07-04T17:07:12.664446+00:00"},{"alias_kind":"pith_short_12","alias_value":"DZ2OJ6XNBMGA","created_at":"2026-07-04T17:07:12.664446+00:00"},{"alias_kind":"pith_short_16","alias_value":"DZ2OJ6XNBMGA5UER","created_at":"2026-07-04T17:07:12.664446+00:00"},{"alias_kind":"pith_short_8","alias_value":"DZ2OJ6XN","created_at":"2026-07-04T17:07:12.664446+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":1,"internal_anchor_count":1,"sample":[{"citing_arxiv_id":"2608.10074","citing_title":"Discovery of four Narrow-line Type-1 Quasars at z = 2.54 -- 6.06 with Subaru 'Onohi'ula PFS-SSP","ref_index":100,"is_internal_anchor":true}]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/DZ2OJ6XNBMGA5UERITBSHCDKBI","json":"https://pith.science/pith/DZ2OJ6XNBMGA5UERITBSHCDKBI.json","graph_json":"https://pith.science/api/pith-number/DZ2OJ6XNBMGA5UERITBSHCDKBI/graph.json","events_json":"https://pith.science/api/pith-number/DZ2OJ6XNBMGA5UERITBSHCDKBI/events.json","paper":"https://pith.science/paper/DZ2OJ6XN"},"agent_actions":{"view_html":"https://pith.science/pith/DZ2OJ6XNBMGA5UERITBSHCDKBI","download_json":"https://pith.science/pith/DZ2OJ6XNBMGA5UERITBSHCDKBI.json","view_paper":"https://pith.science/paper/DZ2OJ6XN","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=0712.1831&json=true","fetch_graph":"https://pith.science/api/pith-number/DZ2OJ6XNBMGA5UERITBSHCDKBI/graph.json","fetch_events":"https://pith.science/api/pith-number/DZ2OJ6XNBMGA5UERITBSHCDKBI/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/DZ2OJ6XNBMGA5UERITBSHCDKBI/action/timestamp_anchor","attest_storage":"https://pith.science/pith/DZ2OJ6XNBMGA5UERITBSHCDKBI/action/storage_attestation","attest_author":"https://pith.science/pith/DZ2OJ6XNBMGA5UERITBSHCDKBI/action/author_attestation","sign_citation":"https://pith.science/pith/DZ2OJ6XNBMGA5UERITBSHCDKBI/action/citation_signature","submit_replication":"https://pith.science/pith/DZ2OJ6XNBMGA5UERITBSHCDKBI/action/replication_record"}},"created_at":"2026-07-04T17:07:12.664446+00:00","updated_at":"2026-07-04T17:07:12.664446+00:00"}