{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2025:D3KL54TYJL7KGRWZV6TJMH6JSP","short_pith_number":"pith:D3KL54TY","canonical_record":{"source":{"id":"2508.17183","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2025-08-24T01:45:44Z","cross_cats_sorted":[],"title_canon_sha256":"ef4ff9ed61ff4304c5490e2ac0e1d5c0e7d72cf6d65f9314a1a3d10d343e87bf","abstract_canon_sha256":"7f74b2b6e93c1ff2de75fa5b2b887feadc75068f6c5eb1c882a296763a56bc76"},"schema_version":"1.0"},"canonical_sha256":"1ed4bef2784afea346d9afa6961fc993f5c71e121313fa51cda0fb26207ee802","source":{"kind":"arxiv","id":"2508.17183","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2508.17183","created_at":"2026-07-05T11:58:37Z"},{"alias_kind":"arxiv_version","alias_value":"2508.17183v1","created_at":"2026-07-05T11:58:37Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2508.17183","created_at":"2026-07-05T11:58:37Z"},{"alias_kind":"pith_short_12","alias_value":"D3KL54TYJL7K","created_at":"2026-07-05T11:58:37Z"},{"alias_kind":"pith_short_16","alias_value":"D3KL54TYJL7KGRWZ","created_at":"2026-07-05T11:58:37Z"},{"alias_kind":"pith_short_8","alias_value":"D3KL54TY","created_at":"2026-07-05T11:58:37Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2025:D3KL54TYJL7KGRWZV6TJMH6JSP","target":"record","payload":{"canonical_record":{"source":{"id":"2508.17183","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2025-08-24T01:45:44Z","cross_cats_sorted":[],"title_canon_sha256":"ef4ff9ed61ff4304c5490e2ac0e1d5c0e7d72cf6d65f9314a1a3d10d343e87bf","abstract_canon_sha256":"7f74b2b6e93c1ff2de75fa5b2b887feadc75068f6c5eb1c882a296763a56bc76"},"schema_version":"1.0"},"canonical_sha256":"1ed4bef2784afea346d9afa6961fc993f5c71e121313fa51cda0fb26207ee802","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T11:58:37.160192Z","signature_b64":"a0twFIrZrodaPnKRSag5eUeBo5MI2EFL/LqjRQ0V1Ew/soIg53r4Wh4DMwEK99sJh6jWTTy1WMD6clh+lEePCQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"1ed4bef2784afea346d9afa6961fc993f5c71e121313fa51cda0fb26207ee802","last_reissued_at":"2026-07-05T11:58:37.159782Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T11:58:37.159782Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2508.17183","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-05T11:58:37Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"jzxjJQBt/MpKpM/47Up2VjOqvB3cH+pZAXao5jb0uJ0ng/KpGzL9Ihp7x4RWmTHuLx70UscEFM5F/dUkjeX4CA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-04T06:57:11.819599Z"},"content_sha256":"55ce6dce3e7f981fdf212e0a5f3ee19e45bfc4eb7dbdaa6f08b0182b5f157406","schema_version":"1.0","event_id":"sha256:55ce6dce3e7f981fdf212e0a5f3ee19e45bfc4eb7dbdaa6f08b0182b5f157406"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2025:D3KL54TYJL7KGRWZV6TJMH6JSP","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Gravitational Instability and Fragmentation in Collapsar Disks Supports the Formation of Sub-Solar Neutron Stars","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.HE","authors_text":"Brian D. Metzger, Yi-Xian Chen","submitted_at":"2025-08-24T01:45:44Z","abstract_excerpt":"We perform three-dimensional shearing-box hydrodynamical simulations to explore the outcome of gravitational instability in the outer regions of neutrino-cooled disks such as those formed from the collapse of rotating massive stars (\"collapsars''). We employ a physical equation of state, optically-thin neutrino cooling, and assume an electron fraction set by the balance of electron/positron pair-capture reactions. Disks in a marginally stable initial state (Toomre parameter Q~ 1) undergo runaway cooling and fragmentation when the dimensionless cooling timescale obeys tau_cool = t_cool*Omega < "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2508.17183","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/2508.17183/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"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-05T11:58:37Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"SN6aJSpSluRDsiqA1kpeKlqXchQ4tGmeVOEdVAwaTLZpbFlvcXQMvaS3JubvcbdXX/jIcZP9jCHARVI6f1FkDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-04T06:57:11.820116Z"},"content_sha256":"15760c50c999ccd80a19a25c25ad7cd9a88414d092b9571da956e76489020ac6","schema_version":"1.0","event_id":"sha256:15760c50c999ccd80a19a25c25ad7cd9a88414d092b9571da956e76489020ac6"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/D3KL54TYJL7KGRWZV6TJMH6JSP/bundle.json","state_url":"https://pith.science/pith/D3KL54TYJL7KGRWZV6TJMH6JSP/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/D3KL54TYJL7KGRWZV6TJMH6JSP/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-08-04T06:57:11Z","links":{"resolver":"https://pith.science/pith/D3KL54TYJL7KGRWZV6TJMH6JSP","bundle":"https://pith.science/pith/D3KL54TYJL7KGRWZV6TJMH6JSP/bundle.json","state":"https://pith.science/pith/D3KL54TYJL7KGRWZV6TJMH6JSP/state.json","well_known_bundle":"https://pith.science/.well-known/pith/D3KL54TYJL7KGRWZV6TJMH6JSP/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2025:D3KL54TYJL7KGRWZV6TJMH6JSP","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":"7f74b2b6e93c1ff2de75fa5b2b887feadc75068f6c5eb1c882a296763a56bc76","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2025-08-24T01:45:44Z","title_canon_sha256":"ef4ff9ed61ff4304c5490e2ac0e1d5c0e7d72cf6d65f9314a1a3d10d343e87bf"},"schema_version":"1.0","source":{"id":"2508.17183","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2508.17183","created_at":"2026-07-05T11:58:37Z"},{"alias_kind":"arxiv_version","alias_value":"2508.17183v1","created_at":"2026-07-05T11:58:37Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2508.17183","created_at":"2026-07-05T11:58:37Z"},{"alias_kind":"pith_short_12","alias_value":"D3KL54TYJL7K","created_at":"2026-07-05T11:58:37Z"},{"alias_kind":"pith_short_16","alias_value":"D3KL54TYJL7KGRWZ","created_at":"2026-07-05T11:58:37Z"},{"alias_kind":"pith_short_8","alias_value":"D3KL54TY","created_at":"2026-07-05T11:58:37Z"}],"graph_snapshots":[{"event_id":"sha256:15760c50c999ccd80a19a25c25ad7cd9a88414d092b9571da956e76489020ac6","target":"graph","created_at":"2026-07-05T11:58:37Z","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/2508.17183/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"We perform three-dimensional shearing-box hydrodynamical simulations to explore the outcome of gravitational instability in the outer regions of neutrino-cooled disks such as those formed from the collapse of rotating massive stars (\"collapsars''). We employ a physical equation of state, optically-thin neutrino cooling, and assume an electron fraction set by the balance of electron/positron pair-capture reactions. Disks in a marginally stable initial state (Toomre parameter Q~ 1) undergo runaway cooling and fragmentation when the dimensionless cooling timescale obeys tau_cool = t_cool*Omega < ","authors_text":"Brian D. Metzger, Yi-Xian Chen","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2025-08-24T01:45:44Z","title":"Gravitational Instability and Fragmentation in Collapsar Disks Supports the Formation of Sub-Solar Neutron Stars"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2508.17183","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":"sha256:55ce6dce3e7f981fdf212e0a5f3ee19e45bfc4eb7dbdaa6f08b0182b5f157406","target":"record","created_at":"2026-07-05T11:58:37Z","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":"7f74b2b6e93c1ff2de75fa5b2b887feadc75068f6c5eb1c882a296763a56bc76","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2025-08-24T01:45:44Z","title_canon_sha256":"ef4ff9ed61ff4304c5490e2ac0e1d5c0e7d72cf6d65f9314a1a3d10d343e87bf"},"schema_version":"1.0","source":{"id":"2508.17183","kind":"arxiv","version":1}},"canonical_sha256":"1ed4bef2784afea346d9afa6961fc993f5c71e121313fa51cda0fb26207ee802","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"1ed4bef2784afea346d9afa6961fc993f5c71e121313fa51cda0fb26207ee802","first_computed_at":"2026-07-05T11:58:37.159782Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T11:58:37.159782Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"a0twFIrZrodaPnKRSag5eUeBo5MI2EFL/LqjRQ0V1Ew/soIg53r4Wh4DMwEK99sJh6jWTTy1WMD6clh+lEePCQ==","signature_status":"signed_v1","signed_at":"2026-07-05T11:58:37.160192Z","signed_message":"canonical_sha256_bytes"},"source_id":"2508.17183","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:55ce6dce3e7f981fdf212e0a5f3ee19e45bfc4eb7dbdaa6f08b0182b5f157406","sha256:15760c50c999ccd80a19a25c25ad7cd9a88414d092b9571da956e76489020ac6"],"state_sha256":"03324ab97322ee4832983d7e4ad66c6813ef6a626c93a9e18a5187b05f148f15"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"oOdj+QrblCLYyZe7JE+TUTNAr2tRagJlNoW1f78NVZUc26C9NTjtzgsF43sDHaNLtpSht2wrGx/LOK3GzUyXBQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-04T06:57:11.824727Z","bundle_sha256":"be00fb5f056d73531d212a114e10d228b3cb99e55dec4fc264336b65ab82001b"}}