{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:1999:NCOU7M4TIFHUEFSU7C6PKNK6NZ","short_pith_number":"pith:NCOU7M4T","canonical_record":{"source":{"id":"astro-ph/9906216","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"1999-06-12T14:07:12Z","cross_cats_sorted":[],"title_canon_sha256":"0954f52dd2f211481ef981ad318c0de7c9b24eb20573a24e2234706d437d69ed","abstract_canon_sha256":"e7bf0af3e301c6c04703cc2426347673b25353dc01ae93b200cb4e0370de9839"},"schema_version":"1.0"},"canonical_sha256":"689d4fb393414f421654f8bcf5355e6e5b11afcf56887465344daa9f35a5e116","source":{"kind":"arxiv","id":"astro-ph/9906216","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/9906216","created_at":"2026-07-04T14:16:47Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/9906216v1","created_at":"2026-07-04T14:16:47Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/9906216","created_at":"2026-07-04T14:16:47Z"},{"alias_kind":"pith_short_12","alias_value":"NCOU7M4TIFHU","created_at":"2026-07-04T14:16:47Z"},{"alias_kind":"pith_short_16","alias_value":"NCOU7M4TIFHUEFSU","created_at":"2026-07-04T14:16:47Z"},{"alias_kind":"pith_short_8","alias_value":"NCOU7M4T","created_at":"2026-07-04T14:16:47Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:1999:NCOU7M4TIFHUEFSU7C6PKNK6NZ","target":"record","payload":{"canonical_record":{"source":{"id":"astro-ph/9906216","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"1999-06-12T14:07:12Z","cross_cats_sorted":[],"title_canon_sha256":"0954f52dd2f211481ef981ad318c0de7c9b24eb20573a24e2234706d437d69ed","abstract_canon_sha256":"e7bf0af3e301c6c04703cc2426347673b25353dc01ae93b200cb4e0370de9839"},"schema_version":"1.0"},"canonical_sha256":"689d4fb393414f421654f8bcf5355e6e5b11afcf56887465344daa9f35a5e116","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-04T14:16:47.721439Z","signature_b64":"YiOt9Qnr0U+4sSKCASs0ndJwdLpwtprazcOtPWpV2r0ajZc87ex8FyIuS8KPeM3kTdkX2vc0/i6vJwFBnJUlCg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"689d4fb393414f421654f8bcf5355e6e5b11afcf56887465344daa9f35a5e116","last_reissued_at":"2026-07-04T14:16:47.720910Z","signature_status":"signed_v1","first_computed_at":"2026-07-04T14:16:47.720910Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"astro-ph/9906216","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":"2026-07-04T14:16:47Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"lsMrTguC4L0iJ4XNkcwTO9S3vptNNYAVvtHtiyPyIGxysmxouuSQPiD0HdbKsHukwlXukC3APi59YmXCilMVAg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-03T16:45:19.599888Z"},"content_sha256":"792098441151a62f848cb6ee00084baff248b5ccab38a0373f11a4a5e76ec740","schema_version":"1.0","event_id":"sha256:792098441151a62f848cb6ee00084baff248b5ccab38a0373f11a4a5e76ec740"},{"event_type":"graph_snapshot","subject_pith_number":"pith:1999:NCOU7M4TIFHUEFSU7C6PKNK6NZ","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Probing Star Formation Timescales in Elliptical Galaxies","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"Daniel Thomas (USM, Garching), Guinevere Kauffmann (MPA, Munich)","submitted_at":"1999-06-12T14:07:12Z","abstract_excerpt":"In models of galaxy formation in a hierarchical Universe, elliptical galaxies form through the merging of smaller disk systems. These models yield a number of testable predictions if reliable techniques for determining the relative ages and compositions of the stellar populations of different galaxies can be found: 1) ellipticals in low-density environments form later than ellipticals in clusters, 2) more massive ellipticals form later, 3) more massive ellipticals form in dissipationless mergers from disk galaxies with low gas content. While colours and the Balmer line strengths of galaxies ca"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/9906216","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/astro-ph/9906216/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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":"2026-07-04T14:16:47Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"KkC3yoaEzi5WpL06AyEEGeCyTbz6WbIRKnUN1RZgnFZCEU/V64Z9rP4M+kcmsD6uw3YuSsGNwSUPqgVCqfM7AQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-03T16:45:19.600392Z"},"content_sha256":"8fa277da6d14175dd3b6c49fb298cf24de86a6f650e2ec72a482ebcf834b4853","schema_version":"1.0","event_id":"sha256:8fa277da6d14175dd3b6c49fb298cf24de86a6f650e2ec72a482ebcf834b4853"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/NCOU7M4TIFHUEFSU7C6PKNK6NZ/bundle.json","state_url":"https://pith.science/pith/NCOU7M4TIFHUEFSU7C6PKNK6NZ/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/NCOU7M4TIFHUEFSU7C6PKNK6NZ/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":"2026-08-03T16:45:19Z","links":{"resolver":"https://pith.science/pith/NCOU7M4TIFHUEFSU7C6PKNK6NZ","bundle":"https://pith.science/pith/NCOU7M4TIFHUEFSU7C6PKNK6NZ/bundle.json","state":"https://pith.science/pith/NCOU7M4TIFHUEFSU7C6PKNK6NZ/state.json","well_known_bundle":"https://pith.science/.well-known/pith/NCOU7M4TIFHUEFSU7C6PKNK6NZ/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:1999:NCOU7M4TIFHUEFSU7C6PKNK6NZ","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":"e7bf0af3e301c6c04703cc2426347673b25353dc01ae93b200cb4e0370de9839","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"1999-06-12T14:07:12Z","title_canon_sha256":"0954f52dd2f211481ef981ad318c0de7c9b24eb20573a24e2234706d437d69ed"},"schema_version":"1.0","source":{"id":"astro-ph/9906216","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/9906216","created_at":"2026-07-04T14:16:47Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/9906216v1","created_at":"2026-07-04T14:16:47Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/9906216","created_at":"2026-07-04T14:16:47Z"},{"alias_kind":"pith_short_12","alias_value":"NCOU7M4TIFHU","created_at":"2026-07-04T14:16:47Z"},{"alias_kind":"pith_short_16","alias_value":"NCOU7M4TIFHUEFSU","created_at":"2026-07-04T14:16:47Z"},{"alias_kind":"pith_short_8","alias_value":"NCOU7M4T","created_at":"2026-07-04T14:16:47Z"}],"graph_snapshots":[{"event_id":"sha256:8fa277da6d14175dd3b6c49fb298cf24de86a6f650e2ec72a482ebcf834b4853","target":"graph","created_at":"2026-07-04T14:16:47Z","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/9906216/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"In models of galaxy formation in a hierarchical Universe, elliptical galaxies form through the merging of smaller disk systems. These models yield a number of testable predictions if reliable techniques for determining the relative ages and compositions of the stellar populations of different galaxies can be found: 1) ellipticals in low-density environments form later than ellipticals in clusters, 2) more massive ellipticals form later, 3) more massive ellipticals form in dissipationless mergers from disk galaxies with low gas content. While colours and the Balmer line strengths of galaxies ca","authors_text":"Daniel Thomas (USM, Garching), Guinevere Kauffmann (MPA, Munich)","cross_cats":[],"headline":"","license":"","primary_cat":"astro-ph","submitted_at":"1999-06-12T14:07:12Z","title":"Probing Star Formation Timescales in Elliptical Galaxies"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/9906216","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":"sha256:792098441151a62f848cb6ee00084baff248b5ccab38a0373f11a4a5e76ec740","target":"record","created_at":"2026-07-04T14:16:47Z","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":"e7bf0af3e301c6c04703cc2426347673b25353dc01ae93b200cb4e0370de9839","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"1999-06-12T14:07:12Z","title_canon_sha256":"0954f52dd2f211481ef981ad318c0de7c9b24eb20573a24e2234706d437d69ed"},"schema_version":"1.0","source":{"id":"astro-ph/9906216","kind":"arxiv","version":1}},"canonical_sha256":"689d4fb393414f421654f8bcf5355e6e5b11afcf56887465344daa9f35a5e116","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"689d4fb393414f421654f8bcf5355e6e5b11afcf56887465344daa9f35a5e116","first_computed_at":"2026-07-04T14:16:47.720910Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T14:16:47.720910Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"YiOt9Qnr0U+4sSKCASs0ndJwdLpwtprazcOtPWpV2r0ajZc87ex8FyIuS8KPeM3kTdkX2vc0/i6vJwFBnJUlCg==","signature_status":"signed_v1","signed_at":"2026-07-04T14:16:47.721439Z","signed_message":"canonical_sha256_bytes"},"source_id":"astro-ph/9906216","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:792098441151a62f848cb6ee00084baff248b5ccab38a0373f11a4a5e76ec740","sha256:8fa277da6d14175dd3b6c49fb298cf24de86a6f650e2ec72a482ebcf834b4853"],"state_sha256":"7efb60da54a9a11d214bf35fc2a8f9fb37753ba9a68de54606892ded7054a1aa"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"abmG4ONw2Tza8o+sQVhHSXtvVUQNx/u7kWJp1FuCb0P0Dy7NM7Bh4B5fIDsywkt4Y1bcxUHEgO5OlGxDy1EwDg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-03T16:45:19.605293Z","bundle_sha256":"5ad21e0e3c1a77baf46b77b07fa37b6fd507d4fef7513686c4d32a7c177394f9"}}