{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:1999:4WGQWKF5JNUKTH3ZZCUDM7I7HE","short_pith_number":"pith:4WGQWKF5","canonical_record":{"source":{"id":"hep-ph/9907491","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"hep-ph","submitted_at":"1999-07-26T14:21:53Z","cross_cats_sorted":["nucl-th"],"title_canon_sha256":"1b82729c0dfe254821c220874d43366907e54982775dca93997ab076b340da28","abstract_canon_sha256":"ae0695c2ab69e0726252a58f04041989d3048a94c0e022f608fe3fc500c42c84"},"schema_version":"1.0"},"canonical_sha256":"e58d0b28bd4b68a99f79c8a8367d1f391b6e7d31bf76be1689e5d239d50e4114","source":{"kind":"arxiv","id":"hep-ph/9907491","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"hep-ph/9907491","created_at":"2026-05-18T02:36:27Z"},{"alias_kind":"arxiv_version","alias_value":"hep-ph/9907491v2","created_at":"2026-05-18T02:36:27Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.hep-ph/9907491","created_at":"2026-05-18T02:36:27Z"},{"alias_kind":"pith_short_12","alias_value":"4WGQWKF5JNUK","created_at":"2026-05-18T12:25:49Z"},{"alias_kind":"pith_short_16","alias_value":"4WGQWKF5JNUKTH3Z","created_at":"2026-05-18T12:25:49Z"},{"alias_kind":"pith_short_8","alias_value":"4WGQWKF5","created_at":"2026-05-18T12:25:49Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:1999:4WGQWKF5JNUKTH3ZZCUDM7I7HE","target":"record","payload":{"canonical_record":{"source":{"id":"hep-ph/9907491","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"hep-ph","submitted_at":"1999-07-26T14:21:53Z","cross_cats_sorted":["nucl-th"],"title_canon_sha256":"1b82729c0dfe254821c220874d43366907e54982775dca93997ab076b340da28","abstract_canon_sha256":"ae0695c2ab69e0726252a58f04041989d3048a94c0e022f608fe3fc500c42c84"},"schema_version":"1.0"},"canonical_sha256":"e58d0b28bd4b68a99f79c8a8367d1f391b6e7d31bf76be1689e5d239d50e4114","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:36:27.671011Z","signature_b64":"iZ8qNTtfSNqovjmCaoMI19EkCy+p9ORuUk+1oGziMWL8e55j3i5ME+gJXnMjcxzTuOAaob70gE34HImYh2e+Bw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"e58d0b28bd4b68a99f79c8a8367d1f391b6e7d31bf76be1689e5d239d50e4114","last_reissued_at":"2026-05-18T02:36:27.670427Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:36:27.670427Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"hep-ph/9907491","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T02:36:27Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"xmQVblUnpg6JpSWxW7gzoEDHQ7jmgErP35FUd+1ASLDIfLgoUrfheMlOn274rSRXAsL8t+nZEUY+jD+0rTiOCA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-27T18:13:13.871243Z"},"content_sha256":"0e0ef5a9e141b2d9cd1a0c069e6aa1da140b2bec73c376102473f5d0dd344450","schema_version":"1.0","event_id":"sha256:0e0ef5a9e141b2d9cd1a0c069e6aa1da140b2bec73c376102473f5d0dd344450"},{"event_type":"graph_snapshot","subject_pith_number":"pith:1999:4WGQWKF5JNUKTH3ZZCUDM7I7HE","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Quark structure of pseudoscalar mesons","license":"","headline":"","cross_cats":["nucl-th"],"primary_cat":"hep-ph","authors_text":"Thorsten Feldmann (Univ. Wuppertal)","submitted_at":"1999-07-26T14:21:53Z","abstract_excerpt":"I review to which extent the properties of pseudoscalar mesons can be understood in terms of the underlying quark (and eventually gluon) structure. Special emphasis is put on the progress in our understanding of eta-eta' mixing. Process-independent mixing parameters are defined, and relations between different bases and conventions are studied. Both, the low-energy description in the framework of Chiral Perturbation Theory and the high-energy application in terms of light-cone wave functions for partonic Fock states, are considered. A thorough discussion of theoretical and phenomenological con"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/9907491","kind":"arxiv","version":2},"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":"2026-05-18T02:36:27Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"lcKFIL+7k/eHXDpbyVo/ynG0xd7R7y5u6Rqk0bwYDKHw9j+PnjsFlvIPpOSKuiLompiraHl+/oKVSGDRic+yCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-27T18:13:13.871604Z"},"content_sha256":"e0c6ecb62b27bcb3bce815cd4a1f30431bbd379f866fd95473766b0b639c8bf7","schema_version":"1.0","event_id":"sha256:e0c6ecb62b27bcb3bce815cd4a1f30431bbd379f866fd95473766b0b639c8bf7"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/4WGQWKF5JNUKTH3ZZCUDM7I7HE/bundle.json","state_url":"https://pith.science/pith/4WGQWKF5JNUKTH3ZZCUDM7I7HE/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/4WGQWKF5JNUKTH3ZZCUDM7I7HE/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":"2026-06-27T18:13:13Z","links":{"resolver":"https://pith.science/pith/4WGQWKF5JNUKTH3ZZCUDM7I7HE","bundle":"https://pith.science/pith/4WGQWKF5JNUKTH3ZZCUDM7I7HE/bundle.json","state":"https://pith.science/pith/4WGQWKF5JNUKTH3ZZCUDM7I7HE/state.json","well_known_bundle":"https://pith.science/.well-known/pith/4WGQWKF5JNUKTH3ZZCUDM7I7HE/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:1999:4WGQWKF5JNUKTH3ZZCUDM7I7HE","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":"ae0695c2ab69e0726252a58f04041989d3048a94c0e022f608fe3fc500c42c84","cross_cats_sorted":["nucl-th"],"license":"","primary_cat":"hep-ph","submitted_at":"1999-07-26T14:21:53Z","title_canon_sha256":"1b82729c0dfe254821c220874d43366907e54982775dca93997ab076b340da28"},"schema_version":"1.0","source":{"id":"hep-ph/9907491","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"hep-ph/9907491","created_at":"2026-05-18T02:36:27Z"},{"alias_kind":"arxiv_version","alias_value":"hep-ph/9907491v2","created_at":"2026-05-18T02:36:27Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.hep-ph/9907491","created_at":"2026-05-18T02:36:27Z"},{"alias_kind":"pith_short_12","alias_value":"4WGQWKF5JNUK","created_at":"2026-05-18T12:25:49Z"},{"alias_kind":"pith_short_16","alias_value":"4WGQWKF5JNUKTH3Z","created_at":"2026-05-18T12:25:49Z"},{"alias_kind":"pith_short_8","alias_value":"4WGQWKF5","created_at":"2026-05-18T12:25:49Z"}],"graph_snapshots":[{"event_id":"sha256:e0c6ecb62b27bcb3bce815cd4a1f30431bbd379f866fd95473766b0b639c8bf7","target":"graph","created_at":"2026-05-18T02:36:27Z","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":"I review to which extent the properties of pseudoscalar mesons can be understood in terms of the underlying quark (and eventually gluon) structure. Special emphasis is put on the progress in our understanding of eta-eta' mixing. Process-independent mixing parameters are defined, and relations between different bases and conventions are studied. Both, the low-energy description in the framework of Chiral Perturbation Theory and the high-energy application in terms of light-cone wave functions for partonic Fock states, are considered. A thorough discussion of theoretical and phenomenological con","authors_text":"Thorsten Feldmann (Univ. Wuppertal)","cross_cats":["nucl-th"],"headline":"","license":"","primary_cat":"hep-ph","submitted_at":"1999-07-26T14:21:53Z","title":"Quark structure of pseudoscalar mesons"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"hep-ph/9907491","kind":"arxiv","version":2},"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":"sha256:0e0ef5a9e141b2d9cd1a0c069e6aa1da140b2bec73c376102473f5d0dd344450","target":"record","created_at":"2026-05-18T02:36:27Z","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":"ae0695c2ab69e0726252a58f04041989d3048a94c0e022f608fe3fc500c42c84","cross_cats_sorted":["nucl-th"],"license":"","primary_cat":"hep-ph","submitted_at":"1999-07-26T14:21:53Z","title_canon_sha256":"1b82729c0dfe254821c220874d43366907e54982775dca93997ab076b340da28"},"schema_version":"1.0","source":{"id":"hep-ph/9907491","kind":"arxiv","version":2}},"canonical_sha256":"e58d0b28bd4b68a99f79c8a8367d1f391b6e7d31bf76be1689e5d239d50e4114","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"e58d0b28bd4b68a99f79c8a8367d1f391b6e7d31bf76be1689e5d239d50e4114","first_computed_at":"2026-05-18T02:36:27.670427Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:36:27.670427Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"iZ8qNTtfSNqovjmCaoMI19EkCy+p9ORuUk+1oGziMWL8e55j3i5ME+gJXnMjcxzTuOAaob70gE34HImYh2e+Bw==","signature_status":"signed_v1","signed_at":"2026-05-18T02:36:27.671011Z","signed_message":"canonical_sha256_bytes"},"source_id":"hep-ph/9907491","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:0e0ef5a9e141b2d9cd1a0c069e6aa1da140b2bec73c376102473f5d0dd344450","sha256:e0c6ecb62b27bcb3bce815cd4a1f30431bbd379f866fd95473766b0b639c8bf7"],"state_sha256":"fadd644a917360470e68d4e90a3fb6bb709f63d3d13f6b105c8dcde9811ce3c9"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"zzJ/YgH46S2ztXLbTLSkJtBioMRFd98rAXh/zLXIVVnd9gfAj8GvpoR8lxpZflUakgAwPI8dUb7xMz58/BeSCQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-27T18:13:13.873561Z","bundle_sha256":"3cbf26e183699e3e53d9f1d044ae3aae4d21525b4e636be66d1ae31f8b0de546"}}