{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2024:RKSMA6CESRJIUB2GACISD4B32Q","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":"e87b7afe22f9774c456de503a8a9b0be738f2de139fbd9c230a8f411d431d41b","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.HE","submitted_at":"2024-09-13T00:53:33Z","title_canon_sha256":"cff22756667670a0a00231c24e8eecb25a50d5ebb78ee48926ba0661a5aa3e58"},"schema_version":"1.0","source":{"id":"2409.08451","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2409.08451","created_at":"2026-07-05T10:03:45Z"},{"alias_kind":"arxiv_version","alias_value":"2409.08451v2","created_at":"2026-07-05T10:03:45Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2409.08451","created_at":"2026-07-05T10:03:45Z"},{"alias_kind":"pith_short_12","alias_value":"RKSMA6CESRJI","created_at":"2026-07-05T10:03:45Z"},{"alias_kind":"pith_short_16","alias_value":"RKSMA6CESRJIUB2G","created_at":"2026-07-05T10:03:45Z"},{"alias_kind":"pith_short_8","alias_value":"RKSMA6CE","created_at":"2026-07-05T10:03:45Z"}],"graph_snapshots":[{"event_id":"sha256:fd8ebea16191d6dc9963096f395d5e0cf31627c54253b304c08d53665d9c4c1f","target":"graph","created_at":"2026-07-05T10:03:45Z","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/2409.08451/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Because of the previously observed stability of the 171-day period, the superorbital modulation of the low-mass X-ray binary 4U 1820-30 was considered a consequence of a third star orbiting around the binary. This study aims to further verify this triple model by testing the stability of superorbital period using the light curves collected by X-ray sky monitoring/scanning telescopes from 1987 to 2023. Both power spectral and phase analysis results indicate a significant change in the superorbital period from 171 days to 167 days over this 36-year span. The evolution of the superorbital phase s","authors_text":"Bo-Chun Chen, Jun-Lei Wu, Wei-Yun Chang, Yi Chou","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.HE","submitted_at":"2024-09-13T00:53:33Z","title":"The Puzzling Superorbital Period Variation of the Low-mass X-ray Binary 4U 1820-30"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2409.08451","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":"sha256:854ee2c74310e267737d3f7aa59f7a457dd867b05c28012128b1d9d26f11c7cd","target":"record","created_at":"2026-07-05T10:03:45Z","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":"e87b7afe22f9774c456de503a8a9b0be738f2de139fbd9c230a8f411d431d41b","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.HE","submitted_at":"2024-09-13T00:53:33Z","title_canon_sha256":"cff22756667670a0a00231c24e8eecb25a50d5ebb78ee48926ba0661a5aa3e58"},"schema_version":"1.0","source":{"id":"2409.08451","kind":"arxiv","version":2}},"canonical_sha256":"8aa4c0784494528a0746009121f03bd43e09bb31a38f9fefff8cc6a66cc08d13","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"8aa4c0784494528a0746009121f03bd43e09bb31a38f9fefff8cc6a66cc08d13","first_computed_at":"2026-07-05T10:03:45.896646Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T10:03:45.896646Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"g9iBfdglx7V35EDvc1CG8JhAfhw8V0qDUpTOrVd1B7RO8ULqIfCnXsPpezmcN/jVGVCc53Ay3KBPkXfE1TECDg==","signature_status":"signed_v1","signed_at":"2026-07-05T10:03:45.897079Z","signed_message":"canonical_sha256_bytes"},"source_id":"2409.08451","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:854ee2c74310e267737d3f7aa59f7a457dd867b05c28012128b1d9d26f11c7cd","sha256:fd8ebea16191d6dc9963096f395d5e0cf31627c54253b304c08d53665d9c4c1f"],"state_sha256":"b23217b18b5aa3dc4a3c8f73f727b4864600a0d1c3354a377d914a1dd4fe4996"}