{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:T4F2MP5ZRYNACCVNOOZBAAWWHG","short_pith_number":"pith:T4F2MP5Z","canonical_record":{"source":{"id":"1901.03103","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2019-01-10T11:25:30Z","cross_cats_sorted":[],"title_canon_sha256":"c1e8e206ecb2f4896a42765957143689097b3549e52ba3e026ee0de2bfa0cb72","abstract_canon_sha256":"886647a28159ac706d75282278635bbb4ef03d7949842d8e02e0e15bb6d7e99c"},"schema_version":"1.0"},"canonical_sha256":"9f0ba63fb98e1a010aad73b21002d6399a699375b68bc92a2c73b6b6c5b3f375","source":{"kind":"arxiv","id":"1901.03103","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1901.03103","created_at":"2026-05-17T23:56:35Z"},{"alias_kind":"arxiv_version","alias_value":"1901.03103v1","created_at":"2026-05-17T23:56:35Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1901.03103","created_at":"2026-05-17T23:56:35Z"},{"alias_kind":"pith_short_12","alias_value":"T4F2MP5ZRYNA","created_at":"2026-05-18T12:33:27Z"},{"alias_kind":"pith_short_16","alias_value":"T4F2MP5ZRYNACCVN","created_at":"2026-05-18T12:33:27Z"},{"alias_kind":"pith_short_8","alias_value":"T4F2MP5Z","created_at":"2026-05-18T12:33:27Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:T4F2MP5ZRYNACCVNOOZBAAWWHG","target":"record","payload":{"canonical_record":{"source":{"id":"1901.03103","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2019-01-10T11:25:30Z","cross_cats_sorted":[],"title_canon_sha256":"c1e8e206ecb2f4896a42765957143689097b3549e52ba3e026ee0de2bfa0cb72","abstract_canon_sha256":"886647a28159ac706d75282278635bbb4ef03d7949842d8e02e0e15bb6d7e99c"},"schema_version":"1.0"},"canonical_sha256":"9f0ba63fb98e1a010aad73b21002d6399a699375b68bc92a2c73b6b6c5b3f375","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:56:35.553609Z","signature_b64":"vFKyRURUPtK2MhIZnnPz30h3UqU8cc/gWNetYG+TVycnpOECmBIJHjEiKj1VLnLQVWdQYh0k8HFL5BsGPE8qDA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"9f0ba63fb98e1a010aad73b21002d6399a699375b68bc92a2c73b6b6c5b3f375","last_reissued_at":"2026-05-17T23:56:35.552968Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:56:35.552968Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1901.03103","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":"2026-05-17T23:56:35Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"67w/lifNpbAThP9cW4wb6a1XqcCWg1OFB1AGmlv8SDfUInVt29yjKp6FGACr/5pv+U353uWcq4vbC3pAaJAjBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T07:23:41.751871Z"},"content_sha256":"9df9028c704ad0d25622107ffa668cec7ba62d38793c21e3d144582f3e33b9e4","schema_version":"1.0","event_id":"sha256:9df9028c704ad0d25622107ffa668cec7ba62d38793c21e3d144582f3e33b9e4"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:T4F2MP5ZRYNACCVNOOZBAAWWHG","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Spectral analysis of the binary nucleus of the planetary nebula Hen 2-428 - first results","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.SR","authors_text":"Marcelo M. Miller Bertolami, Martin A. Barstow, Nicole Reindl, Nicolle L. Finch, Sarah L. Casewell, Stefan Taubenberger, Stephan Geier","submitted_at":"2019-01-10T11:25:30Z","abstract_excerpt":"Identifying progenitor systems for the double-degenerate scenario is crucial to check the reliability of type Ia super-novae as cosmological standard candles. Santander-Garcia et al. (2015) claimed that Hen 2-428 has a double-degenerate core whose combined mass significantly exceeds the Chandrasekhar limit. Together with the short orbital period (4.2 hours), the authors concluded that the system should merge within a Hubble time triggering a type Ia supernova event. Garcia-Berro et al. (2016) explored alternative scenarios to explain the observational evidence, as the high mass conclusion is h"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1901.03103","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":"2026-05-17T23:56:35Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"5WRqsBWn3pj7K3ODjjmzf1/7NZZpUHqw/iQUTAVLhBLyqbzjx7l+/9IOuZcnz6ydpFDBchbTVG7Vkufy3auOBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T07:23:41.752227Z"},"content_sha256":"54ba22482383d1dd28f9d091ec96c7a1ddad195db3fd93fa3c6cadb6f8c331c7","schema_version":"1.0","event_id":"sha256:54ba22482383d1dd28f9d091ec96c7a1ddad195db3fd93fa3c6cadb6f8c331c7"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/T4F2MP5ZRYNACCVNOOZBAAWWHG/bundle.json","state_url":"https://pith.science/pith/T4F2MP5ZRYNACCVNOOZBAAWWHG/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/T4F2MP5ZRYNACCVNOOZBAAWWHG/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":"2026-05-28T07:23:41Z","links":{"resolver":"https://pith.science/pith/T4F2MP5ZRYNACCVNOOZBAAWWHG","bundle":"https://pith.science/pith/T4F2MP5ZRYNACCVNOOZBAAWWHG/bundle.json","state":"https://pith.science/pith/T4F2MP5ZRYNACCVNOOZBAAWWHG/state.json","well_known_bundle":"https://pith.science/.well-known/pith/T4F2MP5ZRYNACCVNOOZBAAWWHG/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:T4F2MP5ZRYNACCVNOOZBAAWWHG","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":"886647a28159ac706d75282278635bbb4ef03d7949842d8e02e0e15bb6d7e99c","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2019-01-10T11:25:30Z","title_canon_sha256":"c1e8e206ecb2f4896a42765957143689097b3549e52ba3e026ee0de2bfa0cb72"},"schema_version":"1.0","source":{"id":"1901.03103","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1901.03103","created_at":"2026-05-17T23:56:35Z"},{"alias_kind":"arxiv_version","alias_value":"1901.03103v1","created_at":"2026-05-17T23:56:35Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1901.03103","created_at":"2026-05-17T23:56:35Z"},{"alias_kind":"pith_short_12","alias_value":"T4F2MP5ZRYNA","created_at":"2026-05-18T12:33:27Z"},{"alias_kind":"pith_short_16","alias_value":"T4F2MP5ZRYNACCVN","created_at":"2026-05-18T12:33:27Z"},{"alias_kind":"pith_short_8","alias_value":"T4F2MP5Z","created_at":"2026-05-18T12:33:27Z"}],"graph_snapshots":[{"event_id":"sha256:54ba22482383d1dd28f9d091ec96c7a1ddad195db3fd93fa3c6cadb6f8c331c7","target":"graph","created_at":"2026-05-17T23:56:35Z","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":"Identifying progenitor systems for the double-degenerate scenario is crucial to check the reliability of type Ia super-novae as cosmological standard candles. Santander-Garcia et al. (2015) claimed that Hen 2-428 has a double-degenerate core whose combined mass significantly exceeds the Chandrasekhar limit. Together with the short orbital period (4.2 hours), the authors concluded that the system should merge within a Hubble time triggering a type Ia supernova event. Garcia-Berro et al. (2016) explored alternative scenarios to explain the observational evidence, as the high mass conclusion is h","authors_text":"Marcelo M. Miller Bertolami, Martin A. Barstow, Nicole Reindl, Nicolle L. Finch, Sarah L. Casewell, Stefan Taubenberger, Stephan Geier","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2019-01-10T11:25:30Z","title":"Spectral analysis of the binary nucleus of the planetary nebula Hen 2-428 - first results"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1901.03103","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":"sha256:9df9028c704ad0d25622107ffa668cec7ba62d38793c21e3d144582f3e33b9e4","target":"record","created_at":"2026-05-17T23:56:35Z","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":"886647a28159ac706d75282278635bbb4ef03d7949842d8e02e0e15bb6d7e99c","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2019-01-10T11:25:30Z","title_canon_sha256":"c1e8e206ecb2f4896a42765957143689097b3549e52ba3e026ee0de2bfa0cb72"},"schema_version":"1.0","source":{"id":"1901.03103","kind":"arxiv","version":1}},"canonical_sha256":"9f0ba63fb98e1a010aad73b21002d6399a699375b68bc92a2c73b6b6c5b3f375","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"9f0ba63fb98e1a010aad73b21002d6399a699375b68bc92a2c73b6b6c5b3f375","first_computed_at":"2026-05-17T23:56:35.552968Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:56:35.552968Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"vFKyRURUPtK2MhIZnnPz30h3UqU8cc/gWNetYG+TVycnpOECmBIJHjEiKj1VLnLQVWdQYh0k8HFL5BsGPE8qDA==","signature_status":"signed_v1","signed_at":"2026-05-17T23:56:35.553609Z","signed_message":"canonical_sha256_bytes"},"source_id":"1901.03103","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:9df9028c704ad0d25622107ffa668cec7ba62d38793c21e3d144582f3e33b9e4","sha256:54ba22482383d1dd28f9d091ec96c7a1ddad195db3fd93fa3c6cadb6f8c331c7"],"state_sha256":"f4a28eed11a2c9fe2fee31f9e0cfb611f60dd43b898a48ea9cb84a7be34fe52c"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"iONohE3A622d+0JIwU373FfgPHMuXUjEoSkeTatYh41UOPU68mxcgD/VvYuRAA3qIAsLiGIMJRd0g+17wyl5AA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-28T07:23:41.754256Z","bundle_sha256":"eaf6f2dff39d8bdbacc1a859b1ffa1bf68de4659b4f9e4eac95a406b70858709"}}