{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2008:K2WHJQOA2LGFUFTWK5G5AWOGYD","short_pith_number":"pith:K2WHJQOA","canonical_record":{"source":{"id":"0806.2741","kind":"arxiv","version":4},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2008-06-17T09:54:30Z","cross_cats_sorted":["physics.atom-ph"],"title_canon_sha256":"b71c4dac067b0b3d5c342a4e7f961c22e28eb75a37f886775bc1948dfea3f727","abstract_canon_sha256":"664a51f4b6962d461a2e48b894c5496763a624e85616f8528131edbcf378c965"},"schema_version":"1.0"},"canonical_sha256":"56ac74c1c0d2cc5a1676574dd059c6c0ec1b37d8ae64738ba1107767c8e43b2d","source":{"kind":"arxiv","id":"0806.2741","version":4},"source_aliases":[{"alias_kind":"arxiv","alias_value":"0806.2741","created_at":"2026-07-04T17:11:18Z"},{"alias_kind":"arxiv_version","alias_value":"0806.2741v4","created_at":"2026-07-04T17:11:18Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0806.2741","created_at":"2026-07-04T17:11:18Z"},{"alias_kind":"pith_short_12","alias_value":"K2WHJQOA2LGF","created_at":"2026-07-04T17:11:18Z"},{"alias_kind":"pith_short_16","alias_value":"K2WHJQOA2LGFUFTW","created_at":"2026-07-04T17:11:18Z"},{"alias_kind":"pith_short_8","alias_value":"K2WHJQOA","created_at":"2026-07-04T17:11:18Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2008:K2WHJQOA2LGFUFTWK5G5AWOGYD","target":"record","payload":{"canonical_record":{"source":{"id":"0806.2741","kind":"arxiv","version":4},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2008-06-17T09:54:30Z","cross_cats_sorted":["physics.atom-ph"],"title_canon_sha256":"b71c4dac067b0b3d5c342a4e7f961c22e28eb75a37f886775bc1948dfea3f727","abstract_canon_sha256":"664a51f4b6962d461a2e48b894c5496763a624e85616f8528131edbcf378c965"},"schema_version":"1.0"},"canonical_sha256":"56ac74c1c0d2cc5a1676574dd059c6c0ec1b37d8ae64738ba1107767c8e43b2d","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-04T17:11:18.471498Z","signature_b64":"k2SxUbC67XUoWU/GHNyxDtZRUxGU5FTaVcpdshByUjDdy7lZbJ3UV14hFXCVzyGAyVGH+WaXldfu2q4m/IuTCg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"56ac74c1c0d2cc5a1676574dd059c6c0ec1b37d8ae64738ba1107767c8e43b2d","last_reissued_at":"2026-07-04T17:11:18.471156Z","signature_status":"signed_v1","first_computed_at":"2026-07-04T17:11:18.471156Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"0806.2741","source_version":4,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-04T17:11:18Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"y/J7kZg9smt9/qsNBLFUVCKgPNu6nYnhRXMFdI++D9TC0xpkjPLWKu+iUMrJvxoiDqc8SpBspMkO2o/bSsflCg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-11T13:25:45.915726Z"},"content_sha256":"f753c1a8c559ec54efaba7349135c89b5043228a53e65aa68ecd10caf83316b1","schema_version":"1.0","event_id":"sha256:f753c1a8c559ec54efaba7349135c89b5043228a53e65aa68ecd10caf83316b1"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2008:K2WHJQOA2LGFUFTWK5G5AWOGYD","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"In situ accurate determination of the zero time delay between two independent ultrashort laser pulses by observing the oscillation of an atomic excited wave packet","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["physics.atom-ph"],"primary_cat":"physics.optics","authors_text":"John W. Hepburn, Qun Zhang","submitted_at":"2008-06-17T09:54:30Z","abstract_excerpt":"We propose a novel method that uses the oscillation of an atomic excited wave packet observed through a pump-probe technique to accurately determine the zero time delay between a pair of ultrashort laser pulses. This physically-based approach provides an easy fix for the intractable problem of synchronizing two different femtosecond laser pulses in a practical experimental environment, especially where an in situ time zero measurement with high accuracy is required."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0806.2741","kind":"arxiv","version":4},"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/0806.2741/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":"2026-07-04T17:11:18Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"bxyCUed+5jzotFwcp7ZwsbTUy+ch7ERpHGUV/re97jRmOEFzyFWFAjvnzsrsFWsk/rpzb1Wl5xoA2tpqqOxnAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-11T13:25:45.916527Z"},"content_sha256":"9bb8160868114ba168ba4cc78b289342bf8087a47b336f806fdb74f8937de823","schema_version":"1.0","event_id":"sha256:9bb8160868114ba168ba4cc78b289342bf8087a47b336f806fdb74f8937de823"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/K2WHJQOA2LGFUFTWK5G5AWOGYD/bundle.json","state_url":"https://pith.science/pith/K2WHJQOA2LGFUFTWK5G5AWOGYD/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/K2WHJQOA2LGFUFTWK5G5AWOGYD/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":"2026-08-11T13:25:45Z","links":{"resolver":"https://pith.science/pith/K2WHJQOA2LGFUFTWK5G5AWOGYD","bundle":"https://pith.science/pith/K2WHJQOA2LGFUFTWK5G5AWOGYD/bundle.json","state":"https://pith.science/pith/K2WHJQOA2LGFUFTWK5G5AWOGYD/state.json","well_known_bundle":"https://pith.science/.well-known/pith/K2WHJQOA2LGFUFTWK5G5AWOGYD/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2008:K2WHJQOA2LGFUFTWK5G5AWOGYD","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":"664a51f4b6962d461a2e48b894c5496763a624e85616f8528131edbcf378c965","cross_cats_sorted":["physics.atom-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2008-06-17T09:54:30Z","title_canon_sha256":"b71c4dac067b0b3d5c342a4e7f961c22e28eb75a37f886775bc1948dfea3f727"},"schema_version":"1.0","source":{"id":"0806.2741","kind":"arxiv","version":4}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"0806.2741","created_at":"2026-07-04T17:11:18Z"},{"alias_kind":"arxiv_version","alias_value":"0806.2741v4","created_at":"2026-07-04T17:11:18Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0806.2741","created_at":"2026-07-04T17:11:18Z"},{"alias_kind":"pith_short_12","alias_value":"K2WHJQOA2LGF","created_at":"2026-07-04T17:11:18Z"},{"alias_kind":"pith_short_16","alias_value":"K2WHJQOA2LGFUFTW","created_at":"2026-07-04T17:11:18Z"},{"alias_kind":"pith_short_8","alias_value":"K2WHJQOA","created_at":"2026-07-04T17:11:18Z"}],"graph_snapshots":[{"event_id":"sha256:9bb8160868114ba168ba4cc78b289342bf8087a47b336f806fdb74f8937de823","target":"graph","created_at":"2026-07-04T17:11:18Z","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/0806.2741/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"We propose a novel method that uses the oscillation of an atomic excited wave packet observed through a pump-probe technique to accurately determine the zero time delay between a pair of ultrashort laser pulses. This physically-based approach provides an easy fix for the intractable problem of synchronizing two different femtosecond laser pulses in a practical experimental environment, especially where an in situ time zero measurement with high accuracy is required.","authors_text":"John W. Hepburn, Qun Zhang","cross_cats":["physics.atom-ph"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2008-06-17T09:54:30Z","title":"In situ accurate determination of the zero time delay between two independent ultrashort laser pulses by observing the oscillation of an atomic excited wave packet"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0806.2741","kind":"arxiv","version":4},"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:f753c1a8c559ec54efaba7349135c89b5043228a53e65aa68ecd10caf83316b1","target":"record","created_at":"2026-07-04T17:11:18Z","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":"664a51f4b6962d461a2e48b894c5496763a624e85616f8528131edbcf378c965","cross_cats_sorted":["physics.atom-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2008-06-17T09:54:30Z","title_canon_sha256":"b71c4dac067b0b3d5c342a4e7f961c22e28eb75a37f886775bc1948dfea3f727"},"schema_version":"1.0","source":{"id":"0806.2741","kind":"arxiv","version":4}},"canonical_sha256":"56ac74c1c0d2cc5a1676574dd059c6c0ec1b37d8ae64738ba1107767c8e43b2d","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"56ac74c1c0d2cc5a1676574dd059c6c0ec1b37d8ae64738ba1107767c8e43b2d","first_computed_at":"2026-07-04T17:11:18.471156Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T17:11:18.471156Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"k2SxUbC67XUoWU/GHNyxDtZRUxGU5FTaVcpdshByUjDdy7lZbJ3UV14hFXCVzyGAyVGH+WaXldfu2q4m/IuTCg==","signature_status":"signed_v1","signed_at":"2026-07-04T17:11:18.471498Z","signed_message":"canonical_sha256_bytes"},"source_id":"0806.2741","source_kind":"arxiv","source_version":4}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:f753c1a8c559ec54efaba7349135c89b5043228a53e65aa68ecd10caf83316b1","sha256:9bb8160868114ba168ba4cc78b289342bf8087a47b336f806fdb74f8937de823"],"state_sha256":"759ba26367e1890ea93ccaebd80989ee1ecb3e5f87a3fc50294c95a07d90df23"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"PxUkY8kbqO16vRNrbKrycg1ix2Ypo2kqN6HcsFs+fHn0k3jNYNIxC9CJMML93KHkvj8s649RjhRRSRay6HfXBg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-11T13:25:45.930501Z","bundle_sha256":"dc10b35c1516cdf8eed2556a4c08219a696c80eb2159a3261c05a75f06736684"}}