{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2013:QFLHWRUKRDT336GOYADFJPZR4K","short_pith_number":"pith:QFLHWRUK","canonical_record":{"source":{"id":"1306.6515","kind":"arxiv","version":3},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"hep-ph","submitted_at":"2013-06-27T14:33:10Z","cross_cats_sorted":["nucl-th"],"title_canon_sha256":"98238ed97c59453a98351f1223d3db7d59cb62174a838c01b7e90f281f6e4ad3","abstract_canon_sha256":"66c00d2011d8e3b8bbe8dce4a06bd9b0ed0706781f1879c247285866a61b11c1"},"schema_version":"1.0"},"canonical_sha256":"81567b468a88e7bdf8cec00654bf31e28068aed786dbb27b59c699c3ede570ef","source":{"kind":"arxiv","id":"1306.6515","version":3},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1306.6515","created_at":"2026-05-18T01:49:07Z"},{"alias_kind":"arxiv_version","alias_value":"1306.6515v3","created_at":"2026-05-18T01:49:07Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1306.6515","created_at":"2026-05-18T01:49:07Z"},{"alias_kind":"pith_short_12","alias_value":"QFLHWRUKRDT3","created_at":"2026-05-18T12:27:57Z"},{"alias_kind":"pith_short_16","alias_value":"QFLHWRUKRDT336GO","created_at":"2026-05-18T12:27:57Z"},{"alias_kind":"pith_short_8","alias_value":"QFLHWRUK","created_at":"2026-05-18T12:27:57Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2013:QFLHWRUKRDT336GOYADFJPZR4K","target":"record","payload":{"canonical_record":{"source":{"id":"1306.6515","kind":"arxiv","version":3},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"hep-ph","submitted_at":"2013-06-27T14:33:10Z","cross_cats_sorted":["nucl-th"],"title_canon_sha256":"98238ed97c59453a98351f1223d3db7d59cb62174a838c01b7e90f281f6e4ad3","abstract_canon_sha256":"66c00d2011d8e3b8bbe8dce4a06bd9b0ed0706781f1879c247285866a61b11c1"},"schema_version":"1.0"},"canonical_sha256":"81567b468a88e7bdf8cec00654bf31e28068aed786dbb27b59c699c3ede570ef","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:49:07.107946Z","signature_b64":"QsHdYdcdFqDHl1I6llsr7TRK+w2T27LPacwtmUAI9EMCuZBQINArVQv7RP2WhdprmGbN+XSLHhm0qWazaPieBg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"81567b468a88e7bdf8cec00654bf31e28068aed786dbb27b59c699c3ede570ef","last_reissued_at":"2026-05-18T01:49:07.107534Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:49:07.107534Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1306.6515","source_version":3,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T01:49:07Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"82luOamUBQVIdynZsHHjbHc3xxRx9MQQ/gqL2qEbgZQo3CBudaVXYrDvvROUACLXQY9R+GpZhaXQZMgNDfrhBg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-28T08:51:10.786346Z"},"content_sha256":"bb0f7be0d3c914272ee928058a50ee75950a53b7913ec40d15fe9e1347ef65eb","schema_version":"1.0","event_id":"sha256:bb0f7be0d3c914272ee928058a50ee75950a53b7913ec40d15fe9e1347ef65eb"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2013:QFLHWRUKRDT336GOYADFJPZR4K","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Parton momentum and helicity distributions in the nucleon","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["nucl-th"],"primary_cat":"hep-ph","authors_text":"J. F. Owens, P. Jimenez-Delgado, W. Melnitchouk","submitted_at":"2013-06-27T14:33:10Z","abstract_excerpt":"We review the current status of spin-averaged and spin-dependent parton distribution functions (PDFs) of the nucleon. After presenting the formalism used to fit PDFs in modern global data analyses, we discuss constraints placed on the PDFs by specific data types. We give representative examples of unpolarized and polarized PDFs and their errors, and list open questions in global QCD fitting. Finally, we anticipate how future facilities, with fixed-target and collider experiments, may impact our knowledge of PDFs and reduce their uncertainties."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1306.6515","kind":"arxiv","version":3},"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":"2026-05-18T01:49:07Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"CE8pwBvAD0u9/decWO0+2AJWOQdMNTzqj31NSfqbJDxCCtt1zm4J1WUcQixaPcggQjUTmMIWE+uNnbzdxNnSCQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-28T08:51:10.786694Z"},"content_sha256":"f8df987f2e6dcb3b5516844e13bd3f2e8fd4452ce1dc3b71b039a42d1be531da","schema_version":"1.0","event_id":"sha256:f8df987f2e6dcb3b5516844e13bd3f2e8fd4452ce1dc3b71b039a42d1be531da"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/QFLHWRUKRDT336GOYADFJPZR4K/bundle.json","state_url":"https://pith.science/pith/QFLHWRUKRDT336GOYADFJPZR4K/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/QFLHWRUKRDT336GOYADFJPZR4K/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":"2026-06-28T08:51:10Z","links":{"resolver":"https://pith.science/pith/QFLHWRUKRDT336GOYADFJPZR4K","bundle":"https://pith.science/pith/QFLHWRUKRDT336GOYADFJPZR4K/bundle.json","state":"https://pith.science/pith/QFLHWRUKRDT336GOYADFJPZR4K/state.json","well_known_bundle":"https://pith.science/.well-known/pith/QFLHWRUKRDT336GOYADFJPZR4K/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2013:QFLHWRUKRDT336GOYADFJPZR4K","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":"66c00d2011d8e3b8bbe8dce4a06bd9b0ed0706781f1879c247285866a61b11c1","cross_cats_sorted":["nucl-th"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"hep-ph","submitted_at":"2013-06-27T14:33:10Z","title_canon_sha256":"98238ed97c59453a98351f1223d3db7d59cb62174a838c01b7e90f281f6e4ad3"},"schema_version":"1.0","source":{"id":"1306.6515","kind":"arxiv","version":3}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1306.6515","created_at":"2026-05-18T01:49:07Z"},{"alias_kind":"arxiv_version","alias_value":"1306.6515v3","created_at":"2026-05-18T01:49:07Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1306.6515","created_at":"2026-05-18T01:49:07Z"},{"alias_kind":"pith_short_12","alias_value":"QFLHWRUKRDT3","created_at":"2026-05-18T12:27:57Z"},{"alias_kind":"pith_short_16","alias_value":"QFLHWRUKRDT336GO","created_at":"2026-05-18T12:27:57Z"},{"alias_kind":"pith_short_8","alias_value":"QFLHWRUK","created_at":"2026-05-18T12:27:57Z"}],"graph_snapshots":[{"event_id":"sha256:f8df987f2e6dcb3b5516844e13bd3f2e8fd4452ce1dc3b71b039a42d1be531da","target":"graph","created_at":"2026-05-18T01:49:07Z","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":"We review the current status of spin-averaged and spin-dependent parton distribution functions (PDFs) of the nucleon. After presenting the formalism used to fit PDFs in modern global data analyses, we discuss constraints placed on the PDFs by specific data types. We give representative examples of unpolarized and polarized PDFs and their errors, and list open questions in global QCD fitting. Finally, we anticipate how future facilities, with fixed-target and collider experiments, may impact our knowledge of PDFs and reduce their uncertainties.","authors_text":"J. F. Owens, P. Jimenez-Delgado, W. Melnitchouk","cross_cats":["nucl-th"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"hep-ph","submitted_at":"2013-06-27T14:33:10Z","title":"Parton momentum and helicity distributions in the nucleon"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1306.6515","kind":"arxiv","version":3},"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:bb0f7be0d3c914272ee928058a50ee75950a53b7913ec40d15fe9e1347ef65eb","target":"record","created_at":"2026-05-18T01:49:07Z","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":"66c00d2011d8e3b8bbe8dce4a06bd9b0ed0706781f1879c247285866a61b11c1","cross_cats_sorted":["nucl-th"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"hep-ph","submitted_at":"2013-06-27T14:33:10Z","title_canon_sha256":"98238ed97c59453a98351f1223d3db7d59cb62174a838c01b7e90f281f6e4ad3"},"schema_version":"1.0","source":{"id":"1306.6515","kind":"arxiv","version":3}},"canonical_sha256":"81567b468a88e7bdf8cec00654bf31e28068aed786dbb27b59c699c3ede570ef","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"81567b468a88e7bdf8cec00654bf31e28068aed786dbb27b59c699c3ede570ef","first_computed_at":"2026-05-18T01:49:07.107534Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:49:07.107534Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"QsHdYdcdFqDHl1I6llsr7TRK+w2T27LPacwtmUAI9EMCuZBQINArVQv7RP2WhdprmGbN+XSLHhm0qWazaPieBg==","signature_status":"signed_v1","signed_at":"2026-05-18T01:49:07.107946Z","signed_message":"canonical_sha256_bytes"},"source_id":"1306.6515","source_kind":"arxiv","source_version":3}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:bb0f7be0d3c914272ee928058a50ee75950a53b7913ec40d15fe9e1347ef65eb","sha256:f8df987f2e6dcb3b5516844e13bd3f2e8fd4452ce1dc3b71b039a42d1be531da"],"state_sha256":"28b5dc4f2b48d0623e96b9d5b067e8d3677a840e770a0c2c3dc0083aa4b69962"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"T4hrqJMuXtuHEax3xBhcye9tB86P9b+O1GoHzd0tLRoEjugWA6sb1bE7z7XYZWqxb3aHZ1SNA1Zy9OIgl1eFAQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-28T08:51:10.788668Z","bundle_sha256":"55e282689a75c1097e172c063c08f32d2a87c45a1632e671decc3615f4554406"}}