{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2000:5P6FYZJUFZFEGK7EBMGDJT4UO2","short_pith_number":"pith:5P6FYZJU","canonical_record":{"source":{"id":"astro-ph/0004287","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"2000-04-20T16:41:17Z","cross_cats_sorted":[],"title_canon_sha256":"b491857048e0620a1fcc5cdcac69e4b80401128bb8dc1cf57af66031f014c175","abstract_canon_sha256":"a5393e4b697780f11577c0fb2880c7c7f57fe8342775cc56b227607eb7f494b5"},"schema_version":"1.0"},"canonical_sha256":"ebfc5c65342e4a432be40b0c34cf94768ed239b4f44761a6ce6d360c5ae23116","source":{"kind":"arxiv","id":"astro-ph/0004287","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/0004287","created_at":"2026-07-04T16:16:19Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/0004287v1","created_at":"2026-07-04T16:16:19Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/0004287","created_at":"2026-07-04T16:16:19Z"},{"alias_kind":"pith_short_12","alias_value":"5P6FYZJUFZFE","created_at":"2026-07-04T16:16:19Z"},{"alias_kind":"pith_short_16","alias_value":"5P6FYZJUFZFEGK7E","created_at":"2026-07-04T16:16:19Z"},{"alias_kind":"pith_short_8","alias_value":"5P6FYZJU","created_at":"2026-07-04T16:16:19Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2000:5P6FYZJUFZFEGK7EBMGDJT4UO2","target":"record","payload":{"canonical_record":{"source":{"id":"astro-ph/0004287","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"2000-04-20T16:41:17Z","cross_cats_sorted":[],"title_canon_sha256":"b491857048e0620a1fcc5cdcac69e4b80401128bb8dc1cf57af66031f014c175","abstract_canon_sha256":"a5393e4b697780f11577c0fb2880c7c7f57fe8342775cc56b227607eb7f494b5"},"schema_version":"1.0"},"canonical_sha256":"ebfc5c65342e4a432be40b0c34cf94768ed239b4f44761a6ce6d360c5ae23116","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-04T16:16:19.833792Z","signature_b64":"TmNEIIJqwjiYpeCW/Xxikrc/chZPa+PE2LANxiKpTc5FHxikPN0OOOsgtEXgeBpUptz+tC8SYM4AzxS/QVt+Cw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"ebfc5c65342e4a432be40b0c34cf94768ed239b4f44761a6ce6d360c5ae23116","last_reissued_at":"2026-07-04T16:16:19.833382Z","signature_status":"signed_v1","first_computed_at":"2026-07-04T16:16:19.833382Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"astro-ph/0004287","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":"2026-07-04T16:16:19Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"46psXmnf+yHF8qFqq2wds+sYNr67fFMhVSJh6St5+QAv12Oj3nhX/T1CoIUtVbhaD4iAjakPZZznp+q6H94lDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-01T02:21:21.005173Z"},"content_sha256":"6c7fc24e87d0abb413992dac815da3d717e490a5717ba55d6f612d62bf48039c","schema_version":"1.0","event_id":"sha256:6c7fc24e87d0abb413992dac815da3d717e490a5717ba55d6f612d62bf48039c"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2000:5P6FYZJUFZFEGK7EBMGDJT4UO2","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"The Optical Gravitational Lensing Experiment. A Hunt for Caustic Crossings in QSO 2237+0305","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"(2) Warsaw University Observatory), A. Udalski (2), G. Pietrzynski (2), I. Soszynski (2), K. Zebrun (2). ((1) Princeton University Observatory, M. Kubiak (2), M. Szymanski (2), P.R. Wozniak (1)","submitted_at":"2000-04-20T16:41:17Z","abstract_excerpt":"In 1998 The Optical Gravitational Lensing Experiment (OGLE) successfully implemented automated data reductions for QSO 2237+0305. Using a new image subtraction method we achieved a differential photometry scatter of 1-5 % for images A-D respectively. Combined with a time sampling of 1-2 times a week this is sufficient for early detection of caustic crossings. Nearly real time photometry of QSO 2237+0305 is available from the OGLE web site http://www.astro.princeton.edu/~ogle/ogle2/huchra.html . During the 1999 observing season, the apparent V magnitude of the A, B, C and D images changed by 0."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0004287","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/astro-ph/0004287/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":"2026-07-04T16:16:19Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"yVRQ8poDbMq1pTLYm8o/J6bYd+xiRhlOXsxCXBE6SvTiAW4lnRTMClm3gVAN9axsGzIt9C1nWehU65uNpZ5VAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-01T02:21:21.005464Z"},"content_sha256":"7d49980098fba207a18ee0d31d1bcf97751e70a900e026ab5d5e3810a2fc27e1","schema_version":"1.0","event_id":"sha256:7d49980098fba207a18ee0d31d1bcf97751e70a900e026ab5d5e3810a2fc27e1"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/5P6FYZJUFZFEGK7EBMGDJT4UO2/bundle.json","state_url":"https://pith.science/pith/5P6FYZJUFZFEGK7EBMGDJT4UO2/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/5P6FYZJUFZFEGK7EBMGDJT4UO2/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":"2026-08-01T02:21:21Z","links":{"resolver":"https://pith.science/pith/5P6FYZJUFZFEGK7EBMGDJT4UO2","bundle":"https://pith.science/pith/5P6FYZJUFZFEGK7EBMGDJT4UO2/bundle.json","state":"https://pith.science/pith/5P6FYZJUFZFEGK7EBMGDJT4UO2/state.json","well_known_bundle":"https://pith.science/.well-known/pith/5P6FYZJUFZFEGK7EBMGDJT4UO2/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2000:5P6FYZJUFZFEGK7EBMGDJT4UO2","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":"a5393e4b697780f11577c0fb2880c7c7f57fe8342775cc56b227607eb7f494b5","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2000-04-20T16:41:17Z","title_canon_sha256":"b491857048e0620a1fcc5cdcac69e4b80401128bb8dc1cf57af66031f014c175"},"schema_version":"1.0","source":{"id":"astro-ph/0004287","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/0004287","created_at":"2026-07-04T16:16:19Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/0004287v1","created_at":"2026-07-04T16:16:19Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/0004287","created_at":"2026-07-04T16:16:19Z"},{"alias_kind":"pith_short_12","alias_value":"5P6FYZJUFZFE","created_at":"2026-07-04T16:16:19Z"},{"alias_kind":"pith_short_16","alias_value":"5P6FYZJUFZFEGK7E","created_at":"2026-07-04T16:16:19Z"},{"alias_kind":"pith_short_8","alias_value":"5P6FYZJU","created_at":"2026-07-04T16:16:19Z"}],"graph_snapshots":[{"event_id":"sha256:7d49980098fba207a18ee0d31d1bcf97751e70a900e026ab5d5e3810a2fc27e1","target":"graph","created_at":"2026-07-04T16:16:19Z","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/astro-ph/0004287/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"In 1998 The Optical Gravitational Lensing Experiment (OGLE) successfully implemented automated data reductions for QSO 2237+0305. Using a new image subtraction method we achieved a differential photometry scatter of 1-5 % for images A-D respectively. Combined with a time sampling of 1-2 times a week this is sufficient for early detection of caustic crossings. Nearly real time photometry of QSO 2237+0305 is available from the OGLE web site http://www.astro.princeton.edu/~ogle/ogle2/huchra.html . During the 1999 observing season, the apparent V magnitude of the A, B, C and D images changed by 0.","authors_text":"(2) Warsaw University Observatory), A. Udalski (2), G. Pietrzynski (2), I. Soszynski (2), K. Zebrun (2). ((1) Princeton University Observatory, M. Kubiak (2), M. Szymanski (2), P.R. Wozniak (1)","cross_cats":[],"headline":"","license":"","primary_cat":"astro-ph","submitted_at":"2000-04-20T16:41:17Z","title":"The Optical Gravitational Lensing Experiment. A Hunt for Caustic Crossings in QSO 2237+0305"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0004287","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":"sha256:6c7fc24e87d0abb413992dac815da3d717e490a5717ba55d6f612d62bf48039c","target":"record","created_at":"2026-07-04T16:16:19Z","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":"a5393e4b697780f11577c0fb2880c7c7f57fe8342775cc56b227607eb7f494b5","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2000-04-20T16:41:17Z","title_canon_sha256":"b491857048e0620a1fcc5cdcac69e4b80401128bb8dc1cf57af66031f014c175"},"schema_version":"1.0","source":{"id":"astro-ph/0004287","kind":"arxiv","version":1}},"canonical_sha256":"ebfc5c65342e4a432be40b0c34cf94768ed239b4f44761a6ce6d360c5ae23116","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"ebfc5c65342e4a432be40b0c34cf94768ed239b4f44761a6ce6d360c5ae23116","first_computed_at":"2026-07-04T16:16:19.833382Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T16:16:19.833382Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"TmNEIIJqwjiYpeCW/Xxikrc/chZPa+PE2LANxiKpTc5FHxikPN0OOOsgtEXgeBpUptz+tC8SYM4AzxS/QVt+Cw==","signature_status":"signed_v1","signed_at":"2026-07-04T16:16:19.833792Z","signed_message":"canonical_sha256_bytes"},"source_id":"astro-ph/0004287","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:6c7fc24e87d0abb413992dac815da3d717e490a5717ba55d6f612d62bf48039c","sha256:7d49980098fba207a18ee0d31d1bcf97751e70a900e026ab5d5e3810a2fc27e1"],"state_sha256":"f9c1559e04ad175ac16d1ea035e0dbe697c5ddbb4b564e7818e69b577a63b07b"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"COAqolTVjo6lGTxsv5QWvo8RL3r05EOwdco0wYZSXDw+7QozWkuWz1/kjuD5pBqoMSQhGEn5JnXMcyIiXS2kCQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-01T02:21:21.008541Z","bundle_sha256":"df199dee4b7fb889afd1fff7ef0e2ba42425039350074784d7f6a900f546d569"}}