{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2001:ID5EOEMOW7FU6EJZZTKC7GXO6Q","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":"c7515b290a8d54aba02dae2a331be8b5d9b311936232b209bcf6229709ac43b9","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2001-11-20T21:08:04Z","title_canon_sha256":"f9213121f925a516a1b8b24df00301fbe163b2420102916cfc90366ab11b95a6"},"schema_version":"1.0","source":{"id":"astro-ph/0111398","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/0111398","created_at":"2026-07-04T16:24:30Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/0111398v1","created_at":"2026-07-04T16:24:30Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/0111398","created_at":"2026-07-04T16:24:30Z"},{"alias_kind":"pith_short_12","alias_value":"ID5EOEMOW7FU","created_at":"2026-07-04T16:24:30Z"},{"alias_kind":"pith_short_16","alias_value":"ID5EOEMOW7FU6EJZ","created_at":"2026-07-04T16:24:30Z"},{"alias_kind":"pith_short_8","alias_value":"ID5EOEMO","created_at":"2026-07-04T16:24:30Z"}],"graph_snapshots":[{"event_id":"sha256:1e01f8978d16d38020b90a8f45b2957fa8054629693226ff1608415c65433c73","target":"graph","created_at":"2026-07-04T16:24:30Z","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"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/astro-ph/0111398/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Intermediate-scale spurs are common in spiral galaxies, but perhaps most distinctively evident in a recent HST image of M51 (Scoville & Rector 2001). We investigate, using time-dependent numerical MHD simulations, how such spurs could form (and subsequently fragment) from the interaction of a gaseous ISM with a stellar spiral arm. We model the gaseous medium as a self-gravitating, magnetized, differentially-rotating, razor-thin disk. The basic flow shocks and compresses as it passes through a local segment of a tightly-wound, trailing stellar spiral arm, modeled as a rigidly-rotating gravitati","authors_text":"Eve C. Ostriker (Univ. of Maryland), Woong-Tae Kim","cross_cats":[],"headline":"","license":"","primary_cat":"astro-ph","submitted_at":"2001-11-20T21:08:04Z","title":"Formation and Fragmentation of Gaseous Spurs in Spiral Galaxies"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0111398","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:bb3fe88a94e60364b48c3d1257afee66742135350ef05455c4d0c3a872217f70","target":"record","created_at":"2026-07-04T16:24:30Z","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":"c7515b290a8d54aba02dae2a331be8b5d9b311936232b209bcf6229709ac43b9","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2001-11-20T21:08:04Z","title_canon_sha256":"f9213121f925a516a1b8b24df00301fbe163b2420102916cfc90366ab11b95a6"},"schema_version":"1.0","source":{"id":"astro-ph/0111398","kind":"arxiv","version":1}},"canonical_sha256":"40fa47118eb7cb4f1139ccd42f9aeef415365272e9196a7b78d9db0a8a6c0472","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"40fa47118eb7cb4f1139ccd42f9aeef415365272e9196a7b78d9db0a8a6c0472","first_computed_at":"2026-07-04T16:24:30.621308Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T16:24:30.621308Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"9p3kan5xf1QZzq2RnvlNQSIOEAZZkchouUhKgLxaIAvi9WqRJ1K1euH93pWJG0StRCxnNoSfaubuDtlV77SoCg==","signature_status":"signed_v1","signed_at":"2026-07-04T16:24:30.621725Z","signed_message":"canonical_sha256_bytes"},"source_id":"astro-ph/0111398","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:bb3fe88a94e60364b48c3d1257afee66742135350ef05455c4d0c3a872217f70","sha256:1e01f8978d16d38020b90a8f45b2957fa8054629693226ff1608415c65433c73"],"state_sha256":"27453e2d773333ebb2cdaa46704969a34f5470eab4c4341baab5447fb0395dfa"}