{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2006:IUJPOY6QLIN73ZQWRF5JRRFJX5","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":"c78a8488382248835016293fcdb59828347cc00ea22f9e54a656b8c3b4ec4351","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2006-09-27T09:40:41Z","title_canon_sha256":"a0dcf67e38a2d30888c0a8bc57bf890d40db8750a622e9e7de5dd6d10bfe018a"},"schema_version":"1.0","source":{"id":"astro-ph/0609742","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/0609742","created_at":"2026-07-04T16:59:27Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/0609742v1","created_at":"2026-07-04T16:59:27Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/0609742","created_at":"2026-07-04T16:59:27Z"},{"alias_kind":"pith_short_12","alias_value":"IUJPOY6QLIN7","created_at":"2026-07-04T16:59:27Z"},{"alias_kind":"pith_short_16","alias_value":"IUJPOY6QLIN73ZQW","created_at":"2026-07-04T16:59:27Z"},{"alias_kind":"pith_short_8","alias_value":"IUJPOY6Q","created_at":"2026-07-04T16:59:27Z"}],"graph_snapshots":[{"event_id":"sha256:17ec8dc52ac4484cc57cf34cb0e0f096bf5899f96628fcc09060c6f99104c819","target":"graph","created_at":"2026-07-04T16:59:27Z","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/0609742/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"The nature of the progenitors of type Ia supernovae is still under controversial debate. KPD 1930+2752 is one of the best SN Ia progenitor candidates known today. The object is a double degenerate system consisting of a subluminous B star (sdB) and a massive white dwarf (WD). Maxted et al. (2000) conclude that the system mass exceeds the Chandrasekhar mass. This conclusion, however, rests on the assumption that the sdB mass is 0.5 Mo. However, recent binary population synthesis calculations suggest that the mass of an sdB star may range from 0.3 Mo to more than 0.7 Mo. It is therefore importan","authors_text":"N. Przybilla, R. Napiwotzki, R.-P. Kudritzki, S. Geier, S. Nesslinger, U. Heber","cross_cats":[],"headline":"","license":"","primary_cat":"astro-ph","submitted_at":"2006-09-27T09:40:41Z","title":"The hot subdwarf B + white dwarf binary KPD 1930+2752 - a Supernova Type Ia progenitor candidate"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0609742","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":"sha256:618dd8c02ab9ff131a3e1b02c02dd376ebe17085fec71900493c1eadb2217da1","target":"record","created_at":"2026-07-04T16:59:27Z","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":"c78a8488382248835016293fcdb59828347cc00ea22f9e54a656b8c3b4ec4351","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2006-09-27T09:40:41Z","title_canon_sha256":"a0dcf67e38a2d30888c0a8bc57bf890d40db8750a622e9e7de5dd6d10bfe018a"},"schema_version":"1.0","source":{"id":"astro-ph/0609742","kind":"arxiv","version":1}},"canonical_sha256":"4512f763d05a1bfde616897a98c4a9bf5953878db968367b4a852767107f1249","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"4512f763d05a1bfde616897a98c4a9bf5953878db968367b4a852767107f1249","first_computed_at":"2026-07-04T16:59:27.640433Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T16:59:27.640433Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"4Rv3Rj7gL+5KZiB5IAfBKQL22xcBgexvo5Go1hWltSpjlvPv8Vgalb2KdbY5yb6qYrq62zxozmLSLnPRG59EAg==","signature_status":"signed_v1","signed_at":"2026-07-04T16:59:27.640928Z","signed_message":"canonical_sha256_bytes"},"source_id":"astro-ph/0609742","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:618dd8c02ab9ff131a3e1b02c02dd376ebe17085fec71900493c1eadb2217da1","sha256:17ec8dc52ac4484cc57cf34cb0e0f096bf5899f96628fcc09060c6f99104c819"],"state_sha256":"9b6d1e8ac7a19c37d3cb546b14553d7317610cad384026be115b22b85abdc884"}