{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2021:RD6SQT4XT55WVODQFSN2JXZVVH","short_pith_number":"pith:RD6SQT4X","canonical_record":{"source":{"id":"2107.13985","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ins-det","submitted_at":"2021-07-26T15:09:44Z","cross_cats_sorted":["nucl-ex"],"title_canon_sha256":"272f8bfdc7fcbd12c3b2a8888f21cee041eb7288ac6607a8e076b4556dbef356","abstract_canon_sha256":"3874641c5e0db2d121542c5ddfa2fbe125856853ed29c5ddca0e72dacab07ea3"},"schema_version":"1.0"},"canonical_sha256":"88fd284f979f7b6ab8702c9ba4df35a9e776f9b0103ba36da8ce43072c066c04","source":{"kind":"arxiv","id":"2107.13985","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2107.13985","created_at":"2026-07-05T03:01:42Z"},{"alias_kind":"arxiv_version","alias_value":"2107.13985v1","created_at":"2026-07-05T03:01:42Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2107.13985","created_at":"2026-07-05T03:01:42Z"},{"alias_kind":"pith_short_12","alias_value":"RD6SQT4XT55W","created_at":"2026-07-05T03:01:42Z"},{"alias_kind":"pith_short_16","alias_value":"RD6SQT4XT55WVODQ","created_at":"2026-07-05T03:01:42Z"},{"alias_kind":"pith_short_8","alias_value":"RD6SQT4X","created_at":"2026-07-05T03:01:42Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2021:RD6SQT4XT55WVODQFSN2JXZVVH","target":"record","payload":{"canonical_record":{"source":{"id":"2107.13985","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ins-det","submitted_at":"2021-07-26T15:09:44Z","cross_cats_sorted":["nucl-ex"],"title_canon_sha256":"272f8bfdc7fcbd12c3b2a8888f21cee041eb7288ac6607a8e076b4556dbef356","abstract_canon_sha256":"3874641c5e0db2d121542c5ddfa2fbe125856853ed29c5ddca0e72dacab07ea3"},"schema_version":"1.0"},"canonical_sha256":"88fd284f979f7b6ab8702c9ba4df35a9e776f9b0103ba36da8ce43072c066c04","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T03:01:42.697555Z","signature_b64":"wZTY4A6AGlg66J7NQYnIwWwLr0SbhVFGPxLsDolp8DPYaVQ9vrwlLrUuF/j+efDa0tHiT8HPB4Mi2vXSNmaLDA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"88fd284f979f7b6ab8702c9ba4df35a9e776f9b0103ba36da8ce43072c066c04","last_reissued_at":"2026-07-05T03:01:42.697155Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T03:01:42.697155Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2107.13985","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":"2026-07-05T03:01:42Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"vJfMoWpiFqxg8jxPenFSiJyx+aXDFTiyk2+S9apw7etQhbcmGjMv5EAePV24BAb8ob/Kbi4wSc/yI658O/1YDQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-06T16:41:53.135403Z"},"content_sha256":"e1ca15b6b362a4171475f99bf9a76ad0e8a42c159e44ca39efd08a48a14e5755","schema_version":"1.0","event_id":"sha256:e1ca15b6b362a4171475f99bf9a76ad0e8a42c159e44ca39efd08a48a14e5755"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2021:RD6SQT4XT55WVODQFSN2JXZVVH","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Applying machine learning to determine impact parameter in nuclear physics experiments","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["nucl-ex"],"primary_cat":"physics.ins-det","authors_text":"Akira Ono, C.Y. Tsang, Dan Cozma, Fupeng Li, J. Estee, J.W. Lee, M.B. Tsang, M. Kaneko, M. Kurata-Nishimura, Qingfeng Li, Rohit Kumar, R. Wang, T. Isobe, T. Murakami, W.G. Lynch, Ying-Xun Zhang, Yongjia Wang","submitted_at":"2021-07-26T15:09:44Z","abstract_excerpt":"Machine Learning (ML) algorithms have been demonstrated to be capable of predicting impact parameter in heavy-ion collisions from transport model simulation events with perfect detector response. We extend the scope of ML application to experimental data by incorporating realistic detector response of the S$\\pi$RIT Time Projection Chamber into the heavy-ion simulation events generated from the UrQMD model to resemble experimental data. At 3 fm, the predicted impact parameter is 2.8 fm if simulation events with perfect detector is used for training and testing; 2.4 fm if detector response is in"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2107.13985","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/2107.13985/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":"2026-07-05T03:01:42Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"R284d64fevBfVfjAZVywOUpAPD4e5wg5Skcrtdl8KDhjUtTeWaDIJSQIbX430h94OdpdxXvcmK9v3hA1+v3VCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-06T16:41:53.136063Z"},"content_sha256":"4440bc90f345fe47e2b09273802a0f91313c6bdfb974c5ed0a704718f246283e","schema_version":"1.0","event_id":"sha256:4440bc90f345fe47e2b09273802a0f91313c6bdfb974c5ed0a704718f246283e"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/RD6SQT4XT55WVODQFSN2JXZVVH/bundle.json","state_url":"https://pith.science/pith/RD6SQT4XT55WVODQFSN2JXZVVH/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/RD6SQT4XT55WVODQFSN2JXZVVH/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":"2026-08-06T16:41:53Z","links":{"resolver":"https://pith.science/pith/RD6SQT4XT55WVODQFSN2JXZVVH","bundle":"https://pith.science/pith/RD6SQT4XT55WVODQFSN2JXZVVH/bundle.json","state":"https://pith.science/pith/RD6SQT4XT55WVODQFSN2JXZVVH/state.json","well_known_bundle":"https://pith.science/.well-known/pith/RD6SQT4XT55WVODQFSN2JXZVVH/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2021:RD6SQT4XT55WVODQFSN2JXZVVH","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":"3874641c5e0db2d121542c5ddfa2fbe125856853ed29c5ddca0e72dacab07ea3","cross_cats_sorted":["nucl-ex"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ins-det","submitted_at":"2021-07-26T15:09:44Z","title_canon_sha256":"272f8bfdc7fcbd12c3b2a8888f21cee041eb7288ac6607a8e076b4556dbef356"},"schema_version":"1.0","source":{"id":"2107.13985","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2107.13985","created_at":"2026-07-05T03:01:42Z"},{"alias_kind":"arxiv_version","alias_value":"2107.13985v1","created_at":"2026-07-05T03:01:42Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2107.13985","created_at":"2026-07-05T03:01:42Z"},{"alias_kind":"pith_short_12","alias_value":"RD6SQT4XT55W","created_at":"2026-07-05T03:01:42Z"},{"alias_kind":"pith_short_16","alias_value":"RD6SQT4XT55WVODQ","created_at":"2026-07-05T03:01:42Z"},{"alias_kind":"pith_short_8","alias_value":"RD6SQT4X","created_at":"2026-07-05T03:01:42Z"}],"graph_snapshots":[{"event_id":"sha256:4440bc90f345fe47e2b09273802a0f91313c6bdfb974c5ed0a704718f246283e","target":"graph","created_at":"2026-07-05T03:01:42Z","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/2107.13985/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Machine Learning (ML) algorithms have been demonstrated to be capable of predicting impact parameter in heavy-ion collisions from transport model simulation events with perfect detector response. We extend the scope of ML application to experimental data by incorporating realistic detector response of the S$\\pi$RIT Time Projection Chamber into the heavy-ion simulation events generated from the UrQMD model to resemble experimental data. At 3 fm, the predicted impact parameter is 2.8 fm if simulation events with perfect detector is used for training and testing; 2.4 fm if detector response is in","authors_text":"Akira Ono, C.Y. Tsang, Dan Cozma, Fupeng Li, J. Estee, J.W. Lee, M.B. Tsang, M. Kaneko, M. Kurata-Nishimura, Qingfeng Li, Rohit Kumar, R. Wang, T. Isobe, T. Murakami, W.G. Lynch, Ying-Xun Zhang, Yongjia Wang","cross_cats":["nucl-ex"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ins-det","submitted_at":"2021-07-26T15:09:44Z","title":"Applying machine learning to determine impact parameter in nuclear physics experiments"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2107.13985","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:e1ca15b6b362a4171475f99bf9a76ad0e8a42c159e44ca39efd08a48a14e5755","target":"record","created_at":"2026-07-05T03:01:42Z","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":"3874641c5e0db2d121542c5ddfa2fbe125856853ed29c5ddca0e72dacab07ea3","cross_cats_sorted":["nucl-ex"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ins-det","submitted_at":"2021-07-26T15:09:44Z","title_canon_sha256":"272f8bfdc7fcbd12c3b2a8888f21cee041eb7288ac6607a8e076b4556dbef356"},"schema_version":"1.0","source":{"id":"2107.13985","kind":"arxiv","version":1}},"canonical_sha256":"88fd284f979f7b6ab8702c9ba4df35a9e776f9b0103ba36da8ce43072c066c04","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"88fd284f979f7b6ab8702c9ba4df35a9e776f9b0103ba36da8ce43072c066c04","first_computed_at":"2026-07-05T03:01:42.697155Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T03:01:42.697155Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"wZTY4A6AGlg66J7NQYnIwWwLr0SbhVFGPxLsDolp8DPYaVQ9vrwlLrUuF/j+efDa0tHiT8HPB4Mi2vXSNmaLDA==","signature_status":"signed_v1","signed_at":"2026-07-05T03:01:42.697555Z","signed_message":"canonical_sha256_bytes"},"source_id":"2107.13985","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:e1ca15b6b362a4171475f99bf9a76ad0e8a42c159e44ca39efd08a48a14e5755","sha256:4440bc90f345fe47e2b09273802a0f91313c6bdfb974c5ed0a704718f246283e"],"state_sha256":"8350cf5022a5ce90470f377ff74cb5151e69fec9297951cb57e3cf20f1189ddb"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"frAYSrDRvehP3tyXa8IfA0jLZiQee1yNXDR63NP1c/Y/iDJRbRjNwpzP4P8RK/ilM+PaXo6nafABl1xQISplBQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-06T16:41:53.142228Z","bundle_sha256":"ed91d246f555753ef760c67e1730686be21b9a33b3eda0843b813126ac28ba12"}}