{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2012:KUWX2NTEHCEWT7JTKX442MAAOB","short_pith_number":"pith:KUWX2NTE","canonical_record":{"source":{"id":"1211.1142","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2012-11-06T08:42:57Z","cross_cats_sorted":[],"title_canon_sha256":"bdded4d897b1c6a3205dd3e0e1f34539eacd13b005524c91e4da2caea4a96e60","abstract_canon_sha256":"ed164d99bb642489fc6caf7e981d02e72d6da2f51754cb3735df4ddb13e44018"},"schema_version":"1.0"},"canonical_sha256":"552d7d3664388969fd3355f9cd30007072ec329d18793f0c30cb39b0d98b01b3","source":{"kind":"arxiv","id":"1211.1142","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1211.1142","created_at":"2026-05-18T01:53:25Z"},{"alias_kind":"arxiv_version","alias_value":"1211.1142v1","created_at":"2026-05-18T01:53:25Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1211.1142","created_at":"2026-05-18T01:53:25Z"},{"alias_kind":"pith_short_12","alias_value":"KUWX2NTEHCEW","created_at":"2026-05-18T12:27:11Z"},{"alias_kind":"pith_short_16","alias_value":"KUWX2NTEHCEWT7JT","created_at":"2026-05-18T12:27:11Z"},{"alias_kind":"pith_short_8","alias_value":"KUWX2NTE","created_at":"2026-05-18T12:27:11Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2012:KUWX2NTEHCEWT7JTKX442MAAOB","target":"record","payload":{"canonical_record":{"source":{"id":"1211.1142","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2012-11-06T08:42:57Z","cross_cats_sorted":[],"title_canon_sha256":"bdded4d897b1c6a3205dd3e0e1f34539eacd13b005524c91e4da2caea4a96e60","abstract_canon_sha256":"ed164d99bb642489fc6caf7e981d02e72d6da2f51754cb3735df4ddb13e44018"},"schema_version":"1.0"},"canonical_sha256":"552d7d3664388969fd3355f9cd30007072ec329d18793f0c30cb39b0d98b01b3","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:53:25.219073Z","signature_b64":"J/XtbSin/YxCxFkO8lA3BIm4Aj8wby9FZyC3AtXWjhZqF1Nf3fWKEpLKu/pUl9D9wx82zBSCvVgjIjOsEpjrBg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"552d7d3664388969fd3355f9cd30007072ec329d18793f0c30cb39b0d98b01b3","last_reissued_at":"2026-05-18T01:53:25.218613Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:53:25.218613Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1211.1142","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":"2026-05-18T01:53:25Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Z0Xjyz0yfVm/3v2FHgOsNHoftwrG6pE5e1bFphaQS+7qXj6L1Q7XjGHDfs7yDeg95cTnuq+QMl9Pr9BF+YMWCg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-24T08:33:08.044549Z"},"content_sha256":"5ca4c60b8684e61814fd94575d4da6e5b67116b43b6d524904db32a374105913","schema_version":"1.0","event_id":"sha256:5ca4c60b8684e61814fd94575d4da6e5b67116b43b6d524904db32a374105913"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2012:KUWX2NTEHCEWT7JTKX442MAAOB","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Searching for multiple stellar populations in the massive, old open cluster Berkeley 39","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"2-INAF OA Padova, 3- Macquarie Univ., 4), 4-Monash Univ., 5-Univ. of Texas Austin), A. Bragaglia (1), C. Sneden (5), E. Carretta (1), R.G. Gratton (2), S. Lucatello (2) (1-INAF OA Bologna, V. D'Orazi (3","submitted_at":"2012-11-06T08:42:57Z","abstract_excerpt":"The most massive star clusters include several generations of stars with a different chemical composition (mainly revealed by an Na-O anti-correlation) while low-mass star clusters appear to be chemically homogeneous. We are investigating the chemical composition of several clusters with masses of a few 10^4 Msun to establish the lower mass limit for the multiple stellar population phenomenon. Using FLAMES@VLT spectra we determine abundances of Fe, O, Na, and several other elements (alpha, Fe-peak, and neutron-capture elements) in the old open cluster Berkeley 39. This is a massive open cluste"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1211.1142","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":"2026-05-18T01:53:25Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"/0U2ZCNk+3JDto8qlgoGi87FCrWtpUKZpjAMwyKRE0wMLa8xjw1iA8kuM6MC9QEylGe9Rc/To27IpH4gmqOeAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-24T08:33:08.045281Z"},"content_sha256":"45553f3c5b32fc09550e49cbbd30a31378a3db41a1370b691eaf4488f8d6be26","schema_version":"1.0","event_id":"sha256:45553f3c5b32fc09550e49cbbd30a31378a3db41a1370b691eaf4488f8d6be26"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/KUWX2NTEHCEWT7JTKX442MAAOB/bundle.json","state_url":"https://pith.science/pith/KUWX2NTEHCEWT7JTKX442MAAOB/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/KUWX2NTEHCEWT7JTKX442MAAOB/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":"2026-05-24T08:33:08Z","links":{"resolver":"https://pith.science/pith/KUWX2NTEHCEWT7JTKX442MAAOB","bundle":"https://pith.science/pith/KUWX2NTEHCEWT7JTKX442MAAOB/bundle.json","state":"https://pith.science/pith/KUWX2NTEHCEWT7JTKX442MAAOB/state.json","well_known_bundle":"https://pith.science/.well-known/pith/KUWX2NTEHCEWT7JTKX442MAAOB/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2012:KUWX2NTEHCEWT7JTKX442MAAOB","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":"ed164d99bb642489fc6caf7e981d02e72d6da2f51754cb3735df4ddb13e44018","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2012-11-06T08:42:57Z","title_canon_sha256":"bdded4d897b1c6a3205dd3e0e1f34539eacd13b005524c91e4da2caea4a96e60"},"schema_version":"1.0","source":{"id":"1211.1142","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1211.1142","created_at":"2026-05-18T01:53:25Z"},{"alias_kind":"arxiv_version","alias_value":"1211.1142v1","created_at":"2026-05-18T01:53:25Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1211.1142","created_at":"2026-05-18T01:53:25Z"},{"alias_kind":"pith_short_12","alias_value":"KUWX2NTEHCEW","created_at":"2026-05-18T12:27:11Z"},{"alias_kind":"pith_short_16","alias_value":"KUWX2NTEHCEWT7JT","created_at":"2026-05-18T12:27:11Z"},{"alias_kind":"pith_short_8","alias_value":"KUWX2NTE","created_at":"2026-05-18T12:27:11Z"}],"graph_snapshots":[{"event_id":"sha256:45553f3c5b32fc09550e49cbbd30a31378a3db41a1370b691eaf4488f8d6be26","target":"graph","created_at":"2026-05-18T01:53:25Z","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":"The most massive star clusters include several generations of stars with a different chemical composition (mainly revealed by an Na-O anti-correlation) while low-mass star clusters appear to be chemically homogeneous. We are investigating the chemical composition of several clusters with masses of a few 10^4 Msun to establish the lower mass limit for the multiple stellar population phenomenon. Using FLAMES@VLT spectra we determine abundances of Fe, O, Na, and several other elements (alpha, Fe-peak, and neutron-capture elements) in the old open cluster Berkeley 39. This is a massive open cluste","authors_text":"2-INAF OA Padova, 3- Macquarie Univ., 4), 4-Monash Univ., 5-Univ. of Texas Austin), A. Bragaglia (1), C. Sneden (5), E. Carretta (1), R.G. Gratton (2), S. Lucatello (2) (1-INAF OA Bologna, V. D'Orazi (3","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2012-11-06T08:42:57Z","title":"Searching for multiple stellar populations in the massive, old open cluster Berkeley 39"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1211.1142","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":"sha256:5ca4c60b8684e61814fd94575d4da6e5b67116b43b6d524904db32a374105913","target":"record","created_at":"2026-05-18T01:53:25Z","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":"ed164d99bb642489fc6caf7e981d02e72d6da2f51754cb3735df4ddb13e44018","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2012-11-06T08:42:57Z","title_canon_sha256":"bdded4d897b1c6a3205dd3e0e1f34539eacd13b005524c91e4da2caea4a96e60"},"schema_version":"1.0","source":{"id":"1211.1142","kind":"arxiv","version":1}},"canonical_sha256":"552d7d3664388969fd3355f9cd30007072ec329d18793f0c30cb39b0d98b01b3","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"552d7d3664388969fd3355f9cd30007072ec329d18793f0c30cb39b0d98b01b3","first_computed_at":"2026-05-18T01:53:25.218613Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:53:25.218613Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"J/XtbSin/YxCxFkO8lA3BIm4Aj8wby9FZyC3AtXWjhZqF1Nf3fWKEpLKu/pUl9D9wx82zBSCvVgjIjOsEpjrBg==","signature_status":"signed_v1","signed_at":"2026-05-18T01:53:25.219073Z","signed_message":"canonical_sha256_bytes"},"source_id":"1211.1142","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:5ca4c60b8684e61814fd94575d4da6e5b67116b43b6d524904db32a374105913","sha256:45553f3c5b32fc09550e49cbbd30a31378a3db41a1370b691eaf4488f8d6be26"],"state_sha256":"5fad72e08437065aa6f13c84cbacfa8a06e8df9004f98ffc9a38530a0d7ee6b6"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"PHh2Fd/iuLRo5O2ZP6cq2PG06vHevLRNCe6g6yYIA/Is8ndiUgXSSYmi9972jdSPlTW6X4+f/Y+pKGjuhgerCw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-24T08:33:08.048533Z","bundle_sha256":"dda6a5d0d2adaee83d3adaa9d2f86c65093a1d06acac44dd96dd332f37282a01"}}