{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2010:P3FPWSJDMQ6X5CEWRQAY6XBEV5","short_pith_number":"pith:P3FPWSJD","canonical_record":{"source":{"id":"1011.4309","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2010-11-18T21:23:46Z","cross_cats_sorted":["astro-ph.GA"],"title_canon_sha256":"b7e875f5a7f743c6037675d6ef6b846422b275d23cba027f9d4a6bf732867470","abstract_canon_sha256":"21102c52b8abc812acd5ac11bc8d0573841c925da67464edad53e1b388c7e2d3"},"schema_version":"1.0"},"canonical_sha256":"7ecafb4923643d7e88968c018f5c24af59437985758baf7349def0aa25a736a1","source":{"kind":"arxiv","id":"1011.4309","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1011.4309","created_at":"2026-05-18T02:04:43Z"},{"alias_kind":"arxiv_version","alias_value":"1011.4309v1","created_at":"2026-05-18T02:04:43Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1011.4309","created_at":"2026-05-18T02:04:43Z"},{"alias_kind":"pith_short_12","alias_value":"P3FPWSJDMQ6X","created_at":"2026-05-18T12:26:12Z"},{"alias_kind":"pith_short_16","alias_value":"P3FPWSJDMQ6X5CEW","created_at":"2026-05-18T12:26:12Z"},{"alias_kind":"pith_short_8","alias_value":"P3FPWSJD","created_at":"2026-05-18T12:26:12Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2010:P3FPWSJDMQ6X5CEWRQAY6XBEV5","target":"record","payload":{"canonical_record":{"source":{"id":"1011.4309","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2010-11-18T21:23:46Z","cross_cats_sorted":["astro-ph.GA"],"title_canon_sha256":"b7e875f5a7f743c6037675d6ef6b846422b275d23cba027f9d4a6bf732867470","abstract_canon_sha256":"21102c52b8abc812acd5ac11bc8d0573841c925da67464edad53e1b388c7e2d3"},"schema_version":"1.0"},"canonical_sha256":"7ecafb4923643d7e88968c018f5c24af59437985758baf7349def0aa25a736a1","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:04:43.737066Z","signature_b64":"YA6In7tKYgKRiFgF9ZrtwHARzDgu4qQ1cljl2gh+ZCGAVD2T79lXdqEVa8yRnu9Ra2JrBTwko4PVLbRZCMV6Cg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"7ecafb4923643d7e88968c018f5c24af59437985758baf7349def0aa25a736a1","last_reissued_at":"2026-05-18T02:04:43.736238Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:04:43.736238Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1011.4309","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":"2026-05-18T02:04:43Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Uqs99ZuxHN22t/1nJMGLb4anZ/yzjE3d+2AQL4abdJPoP11OOf4oJnzbEwk54yhvETzN+rmFY4s8ZPLmLQVwAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-20T06:20:32.279895Z"},"content_sha256":"c6ca85ce821bcf228325b690557feee77bd556eb362adf5eadd3056a860a83cb","schema_version":"1.0","event_id":"sha256:c6ca85ce821bcf228325b690557feee77bd556eb362adf5eadd3056a860a83cb"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2010:P3FPWSJDMQ6X5CEWRQAY6XBEV5","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"How old are the stars in the halo of NGC 5128 (Centaurus A)?","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.GA"],"primary_cat":"astro-ph.CO","authors_text":"(2) McMaster University, (3) Padova Observatory, Canada, Canada), Germany, G. L. H. Harris (4) ((1) ESO, Italy, L. Greggio (3), M. Rejkuba (1), Waterloo University, W. E. Harris (2)","submitted_at":"2010-11-18T21:23:46Z","abstract_excerpt":"NGC 5128 (Centaurus A) is, at the distance of just 3.8 Mpc, the nearest easily observable giant elliptical galaxy. Therefore it is the best target to investigate the early star formation history of an elliptical galaxy. Our aims are to establish when the oldest stars formed in NGC 5128, and whether this galaxy formed stars over a long period. We compare simulated colour-magnitude diagrams with the deep ACS/HST photometry. We find that that the observed colour-magnitude diagram can be reproduced satisfactorily only by simulations that have the bulk of the stars with ages in excess of ~10 Gyr, a"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1011.4309","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":"2026-05-18T02:04:43Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"RVIePY7NN6j9W9+oIuPMUPCpBwOBtcVm9UVehp0/wUDWA+dk/AVT5/QhT8O6SLjJwRVEl/9fTzdH7LdNShXFBQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-20T06:20:32.280249Z"},"content_sha256":"04c12bbf2064bd06cc6dff5f870674555465e1dac4203a0320aabc0719713d25","schema_version":"1.0","event_id":"sha256:04c12bbf2064bd06cc6dff5f870674555465e1dac4203a0320aabc0719713d25"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/P3FPWSJDMQ6X5CEWRQAY6XBEV5/bundle.json","state_url":"https://pith.science/pith/P3FPWSJDMQ6X5CEWRQAY6XBEV5/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/P3FPWSJDMQ6X5CEWRQAY6XBEV5/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":"2026-05-20T06:20:32Z","links":{"resolver":"https://pith.science/pith/P3FPWSJDMQ6X5CEWRQAY6XBEV5","bundle":"https://pith.science/pith/P3FPWSJDMQ6X5CEWRQAY6XBEV5/bundle.json","state":"https://pith.science/pith/P3FPWSJDMQ6X5CEWRQAY6XBEV5/state.json","well_known_bundle":"https://pith.science/.well-known/pith/P3FPWSJDMQ6X5CEWRQAY6XBEV5/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2010:P3FPWSJDMQ6X5CEWRQAY6XBEV5","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":"21102c52b8abc812acd5ac11bc8d0573841c925da67464edad53e1b388c7e2d3","cross_cats_sorted":["astro-ph.GA"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2010-11-18T21:23:46Z","title_canon_sha256":"b7e875f5a7f743c6037675d6ef6b846422b275d23cba027f9d4a6bf732867470"},"schema_version":"1.0","source":{"id":"1011.4309","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1011.4309","created_at":"2026-05-18T02:04:43Z"},{"alias_kind":"arxiv_version","alias_value":"1011.4309v1","created_at":"2026-05-18T02:04:43Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1011.4309","created_at":"2026-05-18T02:04:43Z"},{"alias_kind":"pith_short_12","alias_value":"P3FPWSJDMQ6X","created_at":"2026-05-18T12:26:12Z"},{"alias_kind":"pith_short_16","alias_value":"P3FPWSJDMQ6X5CEW","created_at":"2026-05-18T12:26:12Z"},{"alias_kind":"pith_short_8","alias_value":"P3FPWSJD","created_at":"2026-05-18T12:26:12Z"}],"graph_snapshots":[{"event_id":"sha256:04c12bbf2064bd06cc6dff5f870674555465e1dac4203a0320aabc0719713d25","target":"graph","created_at":"2026-05-18T02:04:43Z","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":"NGC 5128 (Centaurus A) is, at the distance of just 3.8 Mpc, the nearest easily observable giant elliptical galaxy. Therefore it is the best target to investigate the early star formation history of an elliptical galaxy. Our aims are to establish when the oldest stars formed in NGC 5128, and whether this galaxy formed stars over a long period. We compare simulated colour-magnitude diagrams with the deep ACS/HST photometry. We find that that the observed colour-magnitude diagram can be reproduced satisfactorily only by simulations that have the bulk of the stars with ages in excess of ~10 Gyr, a","authors_text":"(2) McMaster University, (3) Padova Observatory, Canada, Canada), Germany, G. L. H. Harris (4) ((1) ESO, Italy, L. Greggio (3), M. Rejkuba (1), Waterloo University, W. E. Harris (2)","cross_cats":["astro-ph.GA"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2010-11-18T21:23:46Z","title":"How old are the stars in the halo of NGC 5128 (Centaurus A)?"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1011.4309","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:c6ca85ce821bcf228325b690557feee77bd556eb362adf5eadd3056a860a83cb","target":"record","created_at":"2026-05-18T02:04:43Z","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":"21102c52b8abc812acd5ac11bc8d0573841c925da67464edad53e1b388c7e2d3","cross_cats_sorted":["astro-ph.GA"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2010-11-18T21:23:46Z","title_canon_sha256":"b7e875f5a7f743c6037675d6ef6b846422b275d23cba027f9d4a6bf732867470"},"schema_version":"1.0","source":{"id":"1011.4309","kind":"arxiv","version":1}},"canonical_sha256":"7ecafb4923643d7e88968c018f5c24af59437985758baf7349def0aa25a736a1","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"7ecafb4923643d7e88968c018f5c24af59437985758baf7349def0aa25a736a1","first_computed_at":"2026-05-18T02:04:43.736238Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:04:43.736238Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"YA6In7tKYgKRiFgF9ZrtwHARzDgu4qQ1cljl2gh+ZCGAVD2T79lXdqEVa8yRnu9Ra2JrBTwko4PVLbRZCMV6Cg==","signature_status":"signed_v1","signed_at":"2026-05-18T02:04:43.737066Z","signed_message":"canonical_sha256_bytes"},"source_id":"1011.4309","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:c6ca85ce821bcf228325b690557feee77bd556eb362adf5eadd3056a860a83cb","sha256:04c12bbf2064bd06cc6dff5f870674555465e1dac4203a0320aabc0719713d25"],"state_sha256":"6befb414aa0e10426b5763ad4c4cd26624bc2750b824e1259db7aa1751a19f0a"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"NPjwPdipAgeS4WEXMe1/sj/WxtmiIpt5+oEl4LJStGeYWkyueRJi5XEwyUWh3p0qWsBsOsRemt2coOiWaA1jCA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-20T06:20:32.282728Z","bundle_sha256":"c64c7ae710246e8db3681ab8915cb82474363a95f91d1deb2220d3c81d7ee559"}}