{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:G4WEYKJTRSQ6H2D367JCEVOZTB","short_pith_number":"pith:G4WEYKJT","canonical_record":{"source":{"id":"1803.04692","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2018-03-13T09:20:07Z","cross_cats_sorted":[],"title_canon_sha256":"068c082a4ee84de7ba38d06abfc9736305d0d5e118050f9ef345c2c0d878495f","abstract_canon_sha256":"620ecc15ff32a03d607bc20519d9e195acb0bc109c5abeaf18d99d8f4c181dd6"},"schema_version":"1.0"},"canonical_sha256":"372c4c29338ca1e3e87bf7d22255d998454bf808be1d3ac03602bb5b92615622","source":{"kind":"arxiv","id":"1803.04692","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1803.04692","created_at":"2026-05-18T00:18:25Z"},{"alias_kind":"arxiv_version","alias_value":"1803.04692v1","created_at":"2026-05-18T00:18:25Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1803.04692","created_at":"2026-05-18T00:18:25Z"},{"alias_kind":"pith_short_12","alias_value":"G4WEYKJTRSQ6","created_at":"2026-05-18T12:32:25Z"},{"alias_kind":"pith_short_16","alias_value":"G4WEYKJTRSQ6H2D3","created_at":"2026-05-18T12:32:25Z"},{"alias_kind":"pith_short_8","alias_value":"G4WEYKJT","created_at":"2026-05-18T12:32:25Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:G4WEYKJTRSQ6H2D367JCEVOZTB","target":"record","payload":{"canonical_record":{"source":{"id":"1803.04692","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2018-03-13T09:20:07Z","cross_cats_sorted":[],"title_canon_sha256":"068c082a4ee84de7ba38d06abfc9736305d0d5e118050f9ef345c2c0d878495f","abstract_canon_sha256":"620ecc15ff32a03d607bc20519d9e195acb0bc109c5abeaf18d99d8f4c181dd6"},"schema_version":"1.0"},"canonical_sha256":"372c4c29338ca1e3e87bf7d22255d998454bf808be1d3ac03602bb5b92615622","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:18:25.154981Z","signature_b64":"sz5MXnf476zCAFcL74yPMt4gk1a2baPbQIQ5WgLv2ocv0tFLFtE2UTXol0Xj5WCSP8RrGxJq++m0o6ijCF4IAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"372c4c29338ca1e3e87bf7d22255d998454bf808be1d3ac03602bb5b92615622","last_reissued_at":"2026-05-18T00:18:25.154426Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:18:25.154426Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1803.04692","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":"2026-05-18T00:18:25Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"4TEI7kP9k/We8OEJQzWwye4/HRmUbOtoTSaaFBg7unyYqfu/wL6KO8thTYyKMzZB8uRjTjw8nLla5w50hD5zCQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-08T23:23:50.947184Z"},"content_sha256":"fda88915d5e1d86330ab8b94daa74186dd7c3c00fa3ccbce5b8cdc9bf107d52f","schema_version":"1.0","event_id":"sha256:fda88915d5e1d86330ab8b94daa74186dd7c3c00fa3ccbce5b8cdc9bf107d52f"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:G4WEYKJTRSQ6H2D367JCEVOZTB","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Can a bright and energetic X-ray pulsar be hiding amid the debris of SN 1987A?","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.HE","authors_text":"D. Lazzati, J. A. Pons, M. Matsuura, N. Rea, P. Esposito, R. Perna","submitted_at":"2018-03-13T09:20:07Z","abstract_excerpt":"The mass of the stellar precursor of supernova (SN) 1987A and the burst of neutrinos observed at the moment of the explosion are consistent with the core-collapse formation of a neutron star. However, no compelling evidence for the presence in SN 1987A of a compact object of any kind has been found yet in any band of the electromagnetic spectrum, prompting questions on whether the neutron star survived and, if it did, on its properties. Starting from the analysis of recent Chandra observations, here we appraise the current observational situation. We derived limits on the X-ray luminosity of a"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1803.04692","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":""},"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":"2026-05-18T00:18:25Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"YkS59RKz43ABGOpFMrRK85IuRvWiWVns0tBlPz8VP5OjqLP5xK2EMQZDPzcgRpY/7IE6CuodXSw2sPa4YHXoAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-08T23:23:50.947542Z"},"content_sha256":"437a4b276d9ffdf4632d34f68cbe3610e027d5671bbe8ec6f950f95f2ea061be","schema_version":"1.0","event_id":"sha256:437a4b276d9ffdf4632d34f68cbe3610e027d5671bbe8ec6f950f95f2ea061be"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/G4WEYKJTRSQ6H2D367JCEVOZTB/bundle.json","state_url":"https://pith.science/pith/G4WEYKJTRSQ6H2D367JCEVOZTB/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/G4WEYKJTRSQ6H2D367JCEVOZTB/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":"2026-06-08T23:23:50Z","links":{"resolver":"https://pith.science/pith/G4WEYKJTRSQ6H2D367JCEVOZTB","bundle":"https://pith.science/pith/G4WEYKJTRSQ6H2D367JCEVOZTB/bundle.json","state":"https://pith.science/pith/G4WEYKJTRSQ6H2D367JCEVOZTB/state.json","well_known_bundle":"https://pith.science/.well-known/pith/G4WEYKJTRSQ6H2D367JCEVOZTB/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:G4WEYKJTRSQ6H2D367JCEVOZTB","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":"620ecc15ff32a03d607bc20519d9e195acb0bc109c5abeaf18d99d8f4c181dd6","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2018-03-13T09:20:07Z","title_canon_sha256":"068c082a4ee84de7ba38d06abfc9736305d0d5e118050f9ef345c2c0d878495f"},"schema_version":"1.0","source":{"id":"1803.04692","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1803.04692","created_at":"2026-05-18T00:18:25Z"},{"alias_kind":"arxiv_version","alias_value":"1803.04692v1","created_at":"2026-05-18T00:18:25Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1803.04692","created_at":"2026-05-18T00:18:25Z"},{"alias_kind":"pith_short_12","alias_value":"G4WEYKJTRSQ6","created_at":"2026-05-18T12:32:25Z"},{"alias_kind":"pith_short_16","alias_value":"G4WEYKJTRSQ6H2D3","created_at":"2026-05-18T12:32:25Z"},{"alias_kind":"pith_short_8","alias_value":"G4WEYKJT","created_at":"2026-05-18T12:32:25Z"}],"graph_snapshots":[{"event_id":"sha256:437a4b276d9ffdf4632d34f68cbe3610e027d5671bbe8ec6f950f95f2ea061be","target":"graph","created_at":"2026-05-18T00:18:25Z","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":"The mass of the stellar precursor of supernova (SN) 1987A and the burst of neutrinos observed at the moment of the explosion are consistent with the core-collapse formation of a neutron star. However, no compelling evidence for the presence in SN 1987A of a compact object of any kind has been found yet in any band of the electromagnetic spectrum, prompting questions on whether the neutron star survived and, if it did, on its properties. Starting from the analysis of recent Chandra observations, here we appraise the current observational situation. We derived limits on the X-ray luminosity of a","authors_text":"D. Lazzati, J. A. Pons, M. Matsuura, N. Rea, P. Esposito, R. Perna","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2018-03-13T09:20:07Z","title":"Can a bright and energetic X-ray pulsar be hiding amid the debris of SN 1987A?"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1803.04692","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:fda88915d5e1d86330ab8b94daa74186dd7c3c00fa3ccbce5b8cdc9bf107d52f","target":"record","created_at":"2026-05-18T00:18:25Z","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":"620ecc15ff32a03d607bc20519d9e195acb0bc109c5abeaf18d99d8f4c181dd6","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2018-03-13T09:20:07Z","title_canon_sha256":"068c082a4ee84de7ba38d06abfc9736305d0d5e118050f9ef345c2c0d878495f"},"schema_version":"1.0","source":{"id":"1803.04692","kind":"arxiv","version":1}},"canonical_sha256":"372c4c29338ca1e3e87bf7d22255d998454bf808be1d3ac03602bb5b92615622","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"372c4c29338ca1e3e87bf7d22255d998454bf808be1d3ac03602bb5b92615622","first_computed_at":"2026-05-18T00:18:25.154426Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:18:25.154426Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"sz5MXnf476zCAFcL74yPMt4gk1a2baPbQIQ5WgLv2ocv0tFLFtE2UTXol0Xj5WCSP8RrGxJq++m0o6ijCF4IAA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:18:25.154981Z","signed_message":"canonical_sha256_bytes"},"source_id":"1803.04692","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:fda88915d5e1d86330ab8b94daa74186dd7c3c00fa3ccbce5b8cdc9bf107d52f","sha256:437a4b276d9ffdf4632d34f68cbe3610e027d5671bbe8ec6f950f95f2ea061be"],"state_sha256":"76b0a3ebfa6db0093d6cfc9e83fcb436fd39022959847302fcfc6654f02d2e7d"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"xVAwzrqy6CaCcY95rXWhUo0qczNZYrnSrhz7UHLSyaap5uHw0LQU/e/iUU6+g57MnMfwFEfSgZw1ex0e/tmlBA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-08T23:23:50.949386Z","bundle_sha256":"339a35d1a2d2a85615e3eb43d54e2fb920aac6197322efec611c7111ad8d2144"}}