{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2021:LJ4PR2NZTDN7UERCLCNRSX45MF","short_pith_number":"pith:LJ4PR2NZ","canonical_record":{"source":{"id":"2107.06748","kind":"arxiv","version":5},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"hep-ph","submitted_at":"2021-07-14T14:47:42Z","cross_cats_sorted":["nucl-ex","nucl-th"],"title_canon_sha256":"5a37e70365e6637d044e75675a331e27dbfcc55c88ab11c0286753206b5f3ced","abstract_canon_sha256":"fd1c6577c70a37abc6c0bbd51e00004349b52d515570d4d15fd0c23240dc39e3"},"schema_version":"1.0"},"canonical_sha256":"5a78f8e9b998dbfa1222589b195f9d617acff86fc783031d8294106097ccbeca","source":{"kind":"arxiv","id":"2107.06748","version":5},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2107.06748","created_at":"2026-07-05T03:55:28Z"},{"alias_kind":"arxiv_version","alias_value":"2107.06748v5","created_at":"2026-07-05T03:55:28Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2107.06748","created_at":"2026-07-05T03:55:28Z"},{"alias_kind":"pith_short_12","alias_value":"LJ4PR2NZTDN7","created_at":"2026-07-05T03:55:28Z"},{"alias_kind":"pith_short_16","alias_value":"LJ4PR2NZTDN7UERC","created_at":"2026-07-05T03:55:28Z"},{"alias_kind":"pith_short_8","alias_value":"LJ4PR2NZ","created_at":"2026-07-05T03:55:28Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2021:LJ4PR2NZTDN7UERCLCNRSX45MF","target":"record","payload":{"canonical_record":{"source":{"id":"2107.06748","kind":"arxiv","version":5},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"hep-ph","submitted_at":"2021-07-14T14:47:42Z","cross_cats_sorted":["nucl-ex","nucl-th"],"title_canon_sha256":"5a37e70365e6637d044e75675a331e27dbfcc55c88ab11c0286753206b5f3ced","abstract_canon_sha256":"fd1c6577c70a37abc6c0bbd51e00004349b52d515570d4d15fd0c23240dc39e3"},"schema_version":"1.0"},"canonical_sha256":"5a78f8e9b998dbfa1222589b195f9d617acff86fc783031d8294106097ccbeca","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T03:55:28.400413Z","signature_b64":"pjYk78QwIMrLk8vZ54Eb5cj7pLC3m31CRmL1gQOhbpLsiYBqwTFnVoW+pJM7zyFKJ6Puy45MEVAqb/P7eYAtBA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"5a78f8e9b998dbfa1222589b195f9d617acff86fc783031d8294106097ccbeca","last_reissued_at":"2026-07-05T03:55:28.399884Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T03:55:28.399884Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2107.06748","source_version":5,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-05T03:55:28Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"kyhwvfcS+/sYx4oL8p1cxJJgmSD6w99lhMsL5uiz1cn+BiAdKHlSywXxQKyno1FCQxCzG0wnEdfQlWbafTm3Dg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-07T05:56:09.416690Z"},"content_sha256":"23e1e3f089554e5efd74e11770be1ed3d5b9b4f76dacf7da7424fa2bad65a421","schema_version":"1.0","event_id":"sha256:23e1e3f089554e5efd74e11770be1ed3d5b9b4f76dacf7da7424fa2bad65a421"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2021:LJ4PR2NZTDN7UERCLCNRSX45MF","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Progress and Opportunities in Backward angle (u-channel) Physics","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["nucl-ex","nucl-th"],"primary_cat":"hep-ph","authors_text":"A. Stanek, B.-G. Yu, B. Pire, C. Ayerbe Gayoso, C. Weiss, D.W. Higinbotham, G.M. Huber, J.M. Laget, J.R. Stevens, K. Park, K. Semenov-Tian-Shansky, {\\L}. Bibrzycki, L. Szymanowski, R.J. Perry, S. Diehl, S. Heppelmann, S.J.D. Kay, S.R. Klein, V. Mathieu, W.B. Li","submitted_at":"2021-07-14T14:47:42Z","abstract_excerpt":"Backward angle (u-channel) scattering provides complementary information for studies of hadron spectroscopy and structure, but has been less comprehensively studied than the corresponding forward angle case. As a result, the physics of u-channel scattering poses a range of new experimental and theoretical opportunities and questions. We summarize recent progress in measuring and understanding high energy reactions with baryon charge exchange in the u-channel, as discussed in the first backward angle (u-channel) Physics Workshop. In particular, we discuss backward angle measurements and their t"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2107.06748","kind":"arxiv","version":5},"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/2107.06748/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":"2026-07-05T03:55:28Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"iscP9fOC8c7v1mIbKZR3VDQbf5En+ljj/XzZCW5Iiu9VxM3/7Ne5NFPg9nO4RCAsgO129UbX1zwOkjkG5ZqeDA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-07T05:56:09.417079Z"},"content_sha256":"f3caba7bb3daafc2195639ce3e1049aad2af7df5b7a89a24402425f77a6ba8db","schema_version":"1.0","event_id":"sha256:f3caba7bb3daafc2195639ce3e1049aad2af7df5b7a89a24402425f77a6ba8db"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/LJ4PR2NZTDN7UERCLCNRSX45MF/bundle.json","state_url":"https://pith.science/pith/LJ4PR2NZTDN7UERCLCNRSX45MF/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/LJ4PR2NZTDN7UERCLCNRSX45MF/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":"2026-07-07T05:56:09Z","links":{"resolver":"https://pith.science/pith/LJ4PR2NZTDN7UERCLCNRSX45MF","bundle":"https://pith.science/pith/LJ4PR2NZTDN7UERCLCNRSX45MF/bundle.json","state":"https://pith.science/pith/LJ4PR2NZTDN7UERCLCNRSX45MF/state.json","well_known_bundle":"https://pith.science/.well-known/pith/LJ4PR2NZTDN7UERCLCNRSX45MF/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2021:LJ4PR2NZTDN7UERCLCNRSX45MF","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":"fd1c6577c70a37abc6c0bbd51e00004349b52d515570d4d15fd0c23240dc39e3","cross_cats_sorted":["nucl-ex","nucl-th"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"hep-ph","submitted_at":"2021-07-14T14:47:42Z","title_canon_sha256":"5a37e70365e6637d044e75675a331e27dbfcc55c88ab11c0286753206b5f3ced"},"schema_version":"1.0","source":{"id":"2107.06748","kind":"arxiv","version":5}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2107.06748","created_at":"2026-07-05T03:55:28Z"},{"alias_kind":"arxiv_version","alias_value":"2107.06748v5","created_at":"2026-07-05T03:55:28Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2107.06748","created_at":"2026-07-05T03:55:28Z"},{"alias_kind":"pith_short_12","alias_value":"LJ4PR2NZTDN7","created_at":"2026-07-05T03:55:28Z"},{"alias_kind":"pith_short_16","alias_value":"LJ4PR2NZTDN7UERC","created_at":"2026-07-05T03:55:28Z"},{"alias_kind":"pith_short_8","alias_value":"LJ4PR2NZ","created_at":"2026-07-05T03:55:28Z"}],"graph_snapshots":[{"event_id":"sha256:f3caba7bb3daafc2195639ce3e1049aad2af7df5b7a89a24402425f77a6ba8db","target":"graph","created_at":"2026-07-05T03:55:28Z","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/2107.06748/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Backward angle (u-channel) scattering provides complementary information for studies of hadron spectroscopy and structure, but has been less comprehensively studied than the corresponding forward angle case. As a result, the physics of u-channel scattering poses a range of new experimental and theoretical opportunities and questions. We summarize recent progress in measuring and understanding high energy reactions with baryon charge exchange in the u-channel, as discussed in the first backward angle (u-channel) Physics Workshop. In particular, we discuss backward angle measurements and their t","authors_text":"A. Stanek, B.-G. Yu, B. Pire, C. Ayerbe Gayoso, C. Weiss, D.W. Higinbotham, G.M. Huber, J.M. Laget, J.R. Stevens, K. Park, K. Semenov-Tian-Shansky, {\\L}. Bibrzycki, L. Szymanowski, R.J. Perry, S. Diehl, S. Heppelmann, S.J.D. Kay, S.R. Klein, V. Mathieu, W.B. Li","cross_cats":["nucl-ex","nucl-th"],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"hep-ph","submitted_at":"2021-07-14T14:47:42Z","title":"Progress and Opportunities in Backward angle (u-channel) Physics"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2107.06748","kind":"arxiv","version":5},"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":"sha256:23e1e3f089554e5efd74e11770be1ed3d5b9b4f76dacf7da7424fa2bad65a421","target":"record","created_at":"2026-07-05T03:55:28Z","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":"fd1c6577c70a37abc6c0bbd51e00004349b52d515570d4d15fd0c23240dc39e3","cross_cats_sorted":["nucl-ex","nucl-th"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"hep-ph","submitted_at":"2021-07-14T14:47:42Z","title_canon_sha256":"5a37e70365e6637d044e75675a331e27dbfcc55c88ab11c0286753206b5f3ced"},"schema_version":"1.0","source":{"id":"2107.06748","kind":"arxiv","version":5}},"canonical_sha256":"5a78f8e9b998dbfa1222589b195f9d617acff86fc783031d8294106097ccbeca","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"5a78f8e9b998dbfa1222589b195f9d617acff86fc783031d8294106097ccbeca","first_computed_at":"2026-07-05T03:55:28.399884Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T03:55:28.399884Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"pjYk78QwIMrLk8vZ54Eb5cj7pLC3m31CRmL1gQOhbpLsiYBqwTFnVoW+pJM7zyFKJ6Puy45MEVAqb/P7eYAtBA==","signature_status":"signed_v1","signed_at":"2026-07-05T03:55:28.400413Z","signed_message":"canonical_sha256_bytes"},"source_id":"2107.06748","source_kind":"arxiv","source_version":5}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:23e1e3f089554e5efd74e11770be1ed3d5b9b4f76dacf7da7424fa2bad65a421","sha256:f3caba7bb3daafc2195639ce3e1049aad2af7df5b7a89a24402425f77a6ba8db"],"state_sha256":"07fbdd23076de526b52221b3ca4fe09ab2a8e6320bba626d78b8ca8683c2d759"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"09IOWUOptfA776eFIy3iQ8SYBSZnbrhtyo/K5SlhIY+OcHw6H753Wt3q7z2v8B0V7pj9DbIyZUsj95eH0hlaDw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-07-07T05:56:09.419296Z","bundle_sha256":"50def17fa68196ebc140297592521d4a9f2da6a23b0d94e5313819a5b3d1d131"}}