{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2004:QEROPFSH4MTQLRIJH3RNQMBQWZ","short_pith_number":"pith:QEROPFSH","canonical_record":{"source":{"id":"astro-ph/0409526","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"2004-09-22T04:39:10Z","cross_cats_sorted":[],"title_canon_sha256":"22728710b4f3bed09fbb442778cfb3468c7c2f965a60164714c2fa77e2d47ae6","abstract_canon_sha256":"cb4477c60fa678fd7dfa375efc1a901ec349c2f09bddc30c4baca149f8e382b6"},"schema_version":"1.0"},"canonical_sha256":"8122e79647e32705c5093ee2d83030b64078b829369a96eb0c4c795849ff3072","source":{"kind":"arxiv","id":"astro-ph/0409526","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/0409526","created_at":"2026-07-04T16:44:44Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/0409526v1","created_at":"2026-07-04T16:44:44Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/0409526","created_at":"2026-07-04T16:44:44Z"},{"alias_kind":"pith_short_12","alias_value":"QEROPFSH4MTQ","created_at":"2026-07-04T16:44:44Z"},{"alias_kind":"pith_short_16","alias_value":"QEROPFSH4MTQLRIJ","created_at":"2026-07-04T16:44:44Z"},{"alias_kind":"pith_short_8","alias_value":"QEROPFSH","created_at":"2026-07-04T16:44:44Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2004:QEROPFSH4MTQLRIJH3RNQMBQWZ","target":"record","payload":{"canonical_record":{"source":{"id":"astro-ph/0409526","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"2004-09-22T04:39:10Z","cross_cats_sorted":[],"title_canon_sha256":"22728710b4f3bed09fbb442778cfb3468c7c2f965a60164714c2fa77e2d47ae6","abstract_canon_sha256":"cb4477c60fa678fd7dfa375efc1a901ec349c2f09bddc30c4baca149f8e382b6"},"schema_version":"1.0"},"canonical_sha256":"8122e79647e32705c5093ee2d83030b64078b829369a96eb0c4c795849ff3072","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-04T16:44:44.239344Z","signature_b64":"kF3LL/QPCSXFWgYdcENPHwjL4K2i/AQ3Vh5qNkAlD3HXDYOgwKKxhmYJT5IYbexDeFIvpevB1BS/8HI9r4FaCA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"8122e79647e32705c5093ee2d83030b64078b829369a96eb0c4c795849ff3072","last_reissued_at":"2026-07-04T16:44:44.238917Z","signature_status":"signed_v1","first_computed_at":"2026-07-04T16:44:44.238917Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"astro-ph/0409526","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":"2026-07-04T16:44:44Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Zli1GHNLdrt3/WgfkJzYUofmWqDeTBDdwxXuEU8NsMqtgfBSKlGL5UcuXw5cPP+kQaZcvBGvEEceiOTbP1TRBA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-02T03:49:04.833924Z"},"content_sha256":"d1266b9f6b8aca2827438aebf78b4a5c6e60ab03790247159bfeb003ade6d04e","schema_version":"1.0","event_id":"sha256:d1266b9f6b8aca2827438aebf78b4a5c6e60ab03790247159bfeb003ade6d04e"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2004:QEROPFSH4MTQLRIJH3RNQMBQWZ","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"A Robust Method for the Analysis of Integrated Spectra from Globular Clusters using Lick Indices","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"Duncan A. Forbes & Michael A. Beasley, Robert N. Proctor","submitted_at":"2004-09-22T04:39:10Z","abstract_excerpt":"We define a method for analysis of the integrated spectra of extra-galactic globular clusters that provides more reliable measures of age, metallicity and alpha-element abundance ratio than have so far been achieved. The method involves the simultaneous fitting of up to 25 Lick indices in a chi-squared-fitting technique that maximises the use of the available data. Here we compare three sets of single stellar population (SSP) models of Lick indices to the high signal-to-noise, integrated spectra of 20 Galactic globular clusters. The ages, [Fe/H] and alpha-element abundance ratios derived from "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0409526","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/0409526/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":"2026-07-04T16:44:44Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"S8kVzx2k8DA/nN2ZaDncsxfzcoV67d+XbDhjHr/TGAlVzmmYrQYkyuNhB3TX9RaaoqbumgHhTbLp7N0xvGYcBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-02T03:49:04.834432Z"},"content_sha256":"f964dda56d302ac8e7dec4597f63e71427afe1c4dbee2ceb6e8327cba2b3f684","schema_version":"1.0","event_id":"sha256:f964dda56d302ac8e7dec4597f63e71427afe1c4dbee2ceb6e8327cba2b3f684"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/QEROPFSH4MTQLRIJH3RNQMBQWZ/bundle.json","state_url":"https://pith.science/pith/QEROPFSH4MTQLRIJH3RNQMBQWZ/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/QEROPFSH4MTQLRIJH3RNQMBQWZ/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":"2026-08-02T03:49:04Z","links":{"resolver":"https://pith.science/pith/QEROPFSH4MTQLRIJH3RNQMBQWZ","bundle":"https://pith.science/pith/QEROPFSH4MTQLRIJH3RNQMBQWZ/bundle.json","state":"https://pith.science/pith/QEROPFSH4MTQLRIJH3RNQMBQWZ/state.json","well_known_bundle":"https://pith.science/.well-known/pith/QEROPFSH4MTQLRIJH3RNQMBQWZ/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2004:QEROPFSH4MTQLRIJH3RNQMBQWZ","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":"cb4477c60fa678fd7dfa375efc1a901ec349c2f09bddc30c4baca149f8e382b6","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2004-09-22T04:39:10Z","title_canon_sha256":"22728710b4f3bed09fbb442778cfb3468c7c2f965a60164714c2fa77e2d47ae6"},"schema_version":"1.0","source":{"id":"astro-ph/0409526","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/0409526","created_at":"2026-07-04T16:44:44Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/0409526v1","created_at":"2026-07-04T16:44:44Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/0409526","created_at":"2026-07-04T16:44:44Z"},{"alias_kind":"pith_short_12","alias_value":"QEROPFSH4MTQ","created_at":"2026-07-04T16:44:44Z"},{"alias_kind":"pith_short_16","alias_value":"QEROPFSH4MTQLRIJ","created_at":"2026-07-04T16:44:44Z"},{"alias_kind":"pith_short_8","alias_value":"QEROPFSH","created_at":"2026-07-04T16:44:44Z"}],"graph_snapshots":[{"event_id":"sha256:f964dda56d302ac8e7dec4597f63e71427afe1c4dbee2ceb6e8327cba2b3f684","target":"graph","created_at":"2026-07-04T16:44:44Z","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/0409526/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"We define a method for analysis of the integrated spectra of extra-galactic globular clusters that provides more reliable measures of age, metallicity and alpha-element abundance ratio than have so far been achieved. The method involves the simultaneous fitting of up to 25 Lick indices in a chi-squared-fitting technique that maximises the use of the available data. Here we compare three sets of single stellar population (SSP) models of Lick indices to the high signal-to-noise, integrated spectra of 20 Galactic globular clusters. The ages, [Fe/H] and alpha-element abundance ratios derived from ","authors_text":"Duncan A. Forbes & Michael A. Beasley, Robert N. Proctor","cross_cats":[],"headline":"","license":"","primary_cat":"astro-ph","submitted_at":"2004-09-22T04:39:10Z","title":"A Robust Method for the Analysis of Integrated Spectra from Globular Clusters using Lick Indices"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0409526","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:d1266b9f6b8aca2827438aebf78b4a5c6e60ab03790247159bfeb003ade6d04e","target":"record","created_at":"2026-07-04T16:44:44Z","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":"cb4477c60fa678fd7dfa375efc1a901ec349c2f09bddc30c4baca149f8e382b6","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2004-09-22T04:39:10Z","title_canon_sha256":"22728710b4f3bed09fbb442778cfb3468c7c2f965a60164714c2fa77e2d47ae6"},"schema_version":"1.0","source":{"id":"astro-ph/0409526","kind":"arxiv","version":1}},"canonical_sha256":"8122e79647e32705c5093ee2d83030b64078b829369a96eb0c4c795849ff3072","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"8122e79647e32705c5093ee2d83030b64078b829369a96eb0c4c795849ff3072","first_computed_at":"2026-07-04T16:44:44.238917Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T16:44:44.238917Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"kF3LL/QPCSXFWgYdcENPHwjL4K2i/AQ3Vh5qNkAlD3HXDYOgwKKxhmYJT5IYbexDeFIvpevB1BS/8HI9r4FaCA==","signature_status":"signed_v1","signed_at":"2026-07-04T16:44:44.239344Z","signed_message":"canonical_sha256_bytes"},"source_id":"astro-ph/0409526","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:d1266b9f6b8aca2827438aebf78b4a5c6e60ab03790247159bfeb003ade6d04e","sha256:f964dda56d302ac8e7dec4597f63e71427afe1c4dbee2ceb6e8327cba2b3f684"],"state_sha256":"c26171e580e7623ee66a841337ccf73998251e04bb6b5bdd1fee53a33dc28402"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"U5r26wPLspJ+3qGzIbR/Bvg77krKZrIdKRo1Dy84dSw3Gxk6mWKecf2OHj8M241DFgvIz4hXcEziz6XoOBbXDg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-02T03:49:04.839350Z","bundle_sha256":"9435bcb53562399c44c0d489dbb439693968653e6d6e89bc6cdfde3bc5e3517a"}}