{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2010:TP4V66TJKTABD3W5EAGL7OGZWB","short_pith_number":"pith:TP4V66TJ","canonical_record":{"source":{"id":"1003.2901","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2010-03-15T11:40:52Z","cross_cats_sorted":[],"title_canon_sha256":"62c0d3d6e3125447749fa47a87f14843ba34e6dc7b7d9e4eb8da7fba7f184979","abstract_canon_sha256":"084dc05806cf1486d1d2af13c4ba8ce2a124e85ecc9c53e77a8072a1a4f69d82"},"schema_version":"1.0"},"canonical_sha256":"9bf95f7a6954c011eedd200cbfb8d9b04ddafc6be517f982d7285004a72d7a70","source":{"kind":"arxiv","id":"1003.2901","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1003.2901","created_at":"2026-05-18T02:08:33Z"},{"alias_kind":"arxiv_version","alias_value":"1003.2901v1","created_at":"2026-05-18T02:08:33Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1003.2901","created_at":"2026-05-18T02:08:33Z"},{"alias_kind":"pith_short_12","alias_value":"TP4V66TJKTAB","created_at":"2026-05-18T12:26:13Z"},{"alias_kind":"pith_short_16","alias_value":"TP4V66TJKTABD3W5","created_at":"2026-05-18T12:26:13Z"},{"alias_kind":"pith_short_8","alias_value":"TP4V66TJ","created_at":"2026-05-18T12:26:13Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2010:TP4V66TJKTABD3W5EAGL7OGZWB","target":"record","payload":{"canonical_record":{"source":{"id":"1003.2901","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2010-03-15T11:40:52Z","cross_cats_sorted":[],"title_canon_sha256":"62c0d3d6e3125447749fa47a87f14843ba34e6dc7b7d9e4eb8da7fba7f184979","abstract_canon_sha256":"084dc05806cf1486d1d2af13c4ba8ce2a124e85ecc9c53e77a8072a1a4f69d82"},"schema_version":"1.0"},"canonical_sha256":"9bf95f7a6954c011eedd200cbfb8d9b04ddafc6be517f982d7285004a72d7a70","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:08:33.909004Z","signature_b64":"twngL4Gpo70AP8nPgOvGKam9V8ueniJ0AXVavHHJRQz7qAjLF+IR1wTKU6cqamAU5/hD+eQZ0IIhzBMOec+fCA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"9bf95f7a6954c011eedd200cbfb8d9b04ddafc6be517f982d7285004a72d7a70","last_reissued_at":"2026-05-18T02:08:33.908104Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:08:33.908104Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1003.2901","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":"2026-05-18T02:08:33Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"pCQTQ2pl24o7dcRMlgQSeu11crkzV+ip+uSsp26dmMiOoOgXR5wZuePyCDqJOHUwX7tZ/AiPnHlXw81oZyg5Cg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T08:39:49.505784Z"},"content_sha256":"e13c8ce25e12182cba6c43ac48298fb7f3ef9e3f4dc3931249aaa66c897cfa2e","schema_version":"1.0","event_id":"sha256:e13c8ce25e12182cba6c43ac48298fb7f3ef9e3f4dc3931249aaa66c897cfa2e"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2010:TP4V66TJKTABD3W5EAGL7OGZWB","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Oxygen isotopic ratios in cool R Coronae Borealis stars","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.SR","authors_text":"D. Anibal Garcia-Hernandez, David L. Lambert, Ken H. Hinkle, Kjell Eriksson, N. Kameswara Rao","submitted_at":"2010-03-15T11:40:52Z","abstract_excerpt":"We investigate the relationship between R Coronae Borealis (RCB) stars and hydrogen-deficient carbon (HdC) stars by measuring precise 16O/18O ratios for five cool RCB stars. The 16O/18O ratios are derived by spectrum synthesis from high-resolution (R=50,000) K-band spectra. Lower limits to the 16O/17O and 14N/15}N ratios as well as Na and S abundances (when possible) are also given. RCB stars in our sample generally display less 18O than HdC stars - the derived 16O/18O ratios range from 3 to 20. The only exception is the RCB star WX CrA, which seems to be a HdC-like star with 16O/18O=0.3. Our "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1003.2901","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":"2026-05-18T02:08:33Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"pWnk3CAtJdssQVbCB6fsH8ndmXwBrgGKY3wD+frn/FU2RI7qfiSx2cM221RiEZ2kz2MP8JAewiWv9H/ktSwuAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T08:39:49.506475Z"},"content_sha256":"5b6dbfb2432462ff34fdfaf3e22178718ddb99b7b686c8033149ca73ad016190","schema_version":"1.0","event_id":"sha256:5b6dbfb2432462ff34fdfaf3e22178718ddb99b7b686c8033149ca73ad016190"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/TP4V66TJKTABD3W5EAGL7OGZWB/bundle.json","state_url":"https://pith.science/pith/TP4V66TJKTABD3W5EAGL7OGZWB/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/TP4V66TJKTABD3W5EAGL7OGZWB/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":"2026-05-31T08:39:49Z","links":{"resolver":"https://pith.science/pith/TP4V66TJKTABD3W5EAGL7OGZWB","bundle":"https://pith.science/pith/TP4V66TJKTABD3W5EAGL7OGZWB/bundle.json","state":"https://pith.science/pith/TP4V66TJKTABD3W5EAGL7OGZWB/state.json","well_known_bundle":"https://pith.science/.well-known/pith/TP4V66TJKTABD3W5EAGL7OGZWB/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2010:TP4V66TJKTABD3W5EAGL7OGZWB","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":"084dc05806cf1486d1d2af13c4ba8ce2a124e85ecc9c53e77a8072a1a4f69d82","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2010-03-15T11:40:52Z","title_canon_sha256":"62c0d3d6e3125447749fa47a87f14843ba34e6dc7b7d9e4eb8da7fba7f184979"},"schema_version":"1.0","source":{"id":"1003.2901","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1003.2901","created_at":"2026-05-18T02:08:33Z"},{"alias_kind":"arxiv_version","alias_value":"1003.2901v1","created_at":"2026-05-18T02:08:33Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1003.2901","created_at":"2026-05-18T02:08:33Z"},{"alias_kind":"pith_short_12","alias_value":"TP4V66TJKTAB","created_at":"2026-05-18T12:26:13Z"},{"alias_kind":"pith_short_16","alias_value":"TP4V66TJKTABD3W5","created_at":"2026-05-18T12:26:13Z"},{"alias_kind":"pith_short_8","alias_value":"TP4V66TJ","created_at":"2026-05-18T12:26:13Z"}],"graph_snapshots":[{"event_id":"sha256:5b6dbfb2432462ff34fdfaf3e22178718ddb99b7b686c8033149ca73ad016190","target":"graph","created_at":"2026-05-18T02:08:33Z","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":"We investigate the relationship between R Coronae Borealis (RCB) stars and hydrogen-deficient carbon (HdC) stars by measuring precise 16O/18O ratios for five cool RCB stars. The 16O/18O ratios are derived by spectrum synthesis from high-resolution (R=50,000) K-band spectra. Lower limits to the 16O/17O and 14N/15}N ratios as well as Na and S abundances (when possible) are also given. RCB stars in our sample generally display less 18O than HdC stars - the derived 16O/18O ratios range from 3 to 20. The only exception is the RCB star WX CrA, which seems to be a HdC-like star with 16O/18O=0.3. Our ","authors_text":"D. Anibal Garcia-Hernandez, David L. Lambert, Ken H. Hinkle, Kjell Eriksson, N. Kameswara Rao","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2010-03-15T11:40:52Z","title":"Oxygen isotopic ratios in cool R Coronae Borealis stars"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1003.2901","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:e13c8ce25e12182cba6c43ac48298fb7f3ef9e3f4dc3931249aaa66c897cfa2e","target":"record","created_at":"2026-05-18T02:08:33Z","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":"084dc05806cf1486d1d2af13c4ba8ce2a124e85ecc9c53e77a8072a1a4f69d82","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2010-03-15T11:40:52Z","title_canon_sha256":"62c0d3d6e3125447749fa47a87f14843ba34e6dc7b7d9e4eb8da7fba7f184979"},"schema_version":"1.0","source":{"id":"1003.2901","kind":"arxiv","version":1}},"canonical_sha256":"9bf95f7a6954c011eedd200cbfb8d9b04ddafc6be517f982d7285004a72d7a70","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"9bf95f7a6954c011eedd200cbfb8d9b04ddafc6be517f982d7285004a72d7a70","first_computed_at":"2026-05-18T02:08:33.908104Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:08:33.908104Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"twngL4Gpo70AP8nPgOvGKam9V8ueniJ0AXVavHHJRQz7qAjLF+IR1wTKU6cqamAU5/hD+eQZ0IIhzBMOec+fCA==","signature_status":"signed_v1","signed_at":"2026-05-18T02:08:33.909004Z","signed_message":"canonical_sha256_bytes"},"source_id":"1003.2901","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:e13c8ce25e12182cba6c43ac48298fb7f3ef9e3f4dc3931249aaa66c897cfa2e","sha256:5b6dbfb2432462ff34fdfaf3e22178718ddb99b7b686c8033149ca73ad016190"],"state_sha256":"fcc9776cdc413658115dd1b45d41c005957584a4b99f11e6595d53e518dde107"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"WqFhpeNvnLyDsMu/v2R5aFDF6wpTRB02N3OkAObU+t7AFx1Zb/U6QmvfeP5jli4eXd7e19c6fakL1FsSu7QKBQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-31T08:39:49.510222Z","bundle_sha256":"af4bb3f574ea8acfd58498b53296874a0504c245f3e0490d05e1692d7feebe28"}}