{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2020:ZLWN7QCY5MO5FEIOS3FPBPPIEP","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":"16501e08a8cfe2526c674b874309ba67b38dfe97416b84d3e1a305e26ecab1a5","cross_cats_sorted":["astro-ph.SR","physics.geo-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2020-07-03T18:08:09Z","title_canon_sha256":"05104f03f760cc599a95a49b6e00004d16b998f77025bc2e86d1060e687d8b91"},"schema_version":"1.0","source":{"id":"2007.01887","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2007.01887","created_at":"2026-07-05T01:33:21Z"},{"alias_kind":"arxiv_version","alias_value":"2007.01887v2","created_at":"2026-07-05T01:33:21Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2007.01887","created_at":"2026-07-05T01:33:21Z"},{"alias_kind":"pith_short_12","alias_value":"ZLWN7QCY5MO5","created_at":"2026-07-05T01:33:21Z"},{"alias_kind":"pith_short_16","alias_value":"ZLWN7QCY5MO5FEIO","created_at":"2026-07-05T01:33:21Z"},{"alias_kind":"pith_short_8","alias_value":"ZLWN7QCY","created_at":"2026-07-05T01:33:21Z"}],"graph_snapshots":[{"event_id":"sha256:2c38389bb073042b836a59df41388016a89cae2fd5db7041da8969564d7e6cc4","target":"graph","created_at":"2026-07-05T01:33:21Z","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/2007.01887/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"The Late Devonian was a protracted period of low speciation resulting in biodiversity decline, culminating in extinction events near the Devonian-Carboniferous boundary. Recent evidence indicates that the final extinction event may have coincided with a dramatic drop in stratospheric ozone, possibly due to a global temperature rise. Here we study an alternative possible cause for the postulated ozone drop: a nearby supernova explosion that could inflict damage by accelerating cosmic rays that can deliver ionizing radiation for up to $\\sim 100$ kyr. We therefore propose that the end-Devonian ex","authors_text":"Adrian L. Melott, Adrienne F. Ertel, Brian C. Thomas, Brian D. Fields, Brian J. Fry, Bruce S. Lieberman, Jesse A. Miller, John Ellis, Zhenghai Liu","cross_cats":["astro-ph.SR","physics.geo-ph"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2020-07-03T18:08:09Z","title":"Supernova Triggers for End-Devonian Extinctions"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2007.01887","kind":"arxiv","version":2},"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":"sha256:822d582aced4b727be487f1a4ef7286136b389ed56d9bcc1a5ce11bbe62d05ec","target":"record","created_at":"2026-07-05T01:33:21Z","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":"16501e08a8cfe2526c674b874309ba67b38dfe97416b84d3e1a305e26ecab1a5","cross_cats_sorted":["astro-ph.SR","physics.geo-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2020-07-03T18:08:09Z","title_canon_sha256":"05104f03f760cc599a95a49b6e00004d16b998f77025bc2e86d1060e687d8b91"},"schema_version":"1.0","source":{"id":"2007.01887","kind":"arxiv","version":2}},"canonical_sha256":"caecdfc058eb1dd2910e96caf0bde823c2bbcdad1ce5ec74a304bbd733dce7e3","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"caecdfc058eb1dd2910e96caf0bde823c2bbcdad1ce5ec74a304bbd733dce7e3","first_computed_at":"2026-07-05T01:33:21.794856Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T01:33:21.794856Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"xVXPh5Dwkb0+4RkJ6eL5dj5r+dLVEKWIlDND4DDIyzhDg6TCyahrb1KMxmqvfpGJadLhSqKboG8wlny+gjZGAA==","signature_status":"signed_v1","signed_at":"2026-07-05T01:33:21.795335Z","signed_message":"canonical_sha256_bytes"},"source_id":"2007.01887","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:822d582aced4b727be487f1a4ef7286136b389ed56d9bcc1a5ce11bbe62d05ec","sha256:2c38389bb073042b836a59df41388016a89cae2fd5db7041da8969564d7e6cc4"],"state_sha256":"0342710368184f0e35d9168b48cb6f7448ee0ad9007bca321e85bd387caac0d2"}