{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2005:7ZOXX4TNRRVTPRDU6BQPQNGDNV","short_pith_number":"pith:7ZOXX4TN","canonical_record":{"source":{"id":"astro-ph/0501489","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"2005-01-22T21:07:45Z","cross_cats_sorted":[],"title_canon_sha256":"45c63249c77595953812523739d31aca9c3a4f1519761700a117d58fec81982e","abstract_canon_sha256":"9ece23491f0c2d6953cf80c823ca8ecd303a3bba0a13d006239c593d233829a3"},"schema_version":"1.0"},"canonical_sha256":"fe5d7bf26d8c6b37c474f060f834c36d596f52d626bab9cdf25f7afb4c34762a","source":{"kind":"arxiv","id":"astro-ph/0501489","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/0501489","created_at":"2026-07-04T16:50:41Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/0501489v1","created_at":"2026-07-04T16:50:41Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/0501489","created_at":"2026-07-04T16:50:41Z"},{"alias_kind":"pith_short_12","alias_value":"7ZOXX4TNRRVT","created_at":"2026-07-04T16:50:41Z"},{"alias_kind":"pith_short_16","alias_value":"7ZOXX4TNRRVTPRDU","created_at":"2026-07-04T16:50:41Z"},{"alias_kind":"pith_short_8","alias_value":"7ZOXX4TN","created_at":"2026-07-04T16:50:41Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2005:7ZOXX4TNRRVTPRDU6BQPQNGDNV","target":"record","payload":{"canonical_record":{"source":{"id":"astro-ph/0501489","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"2005-01-22T21:07:45Z","cross_cats_sorted":[],"title_canon_sha256":"45c63249c77595953812523739d31aca9c3a4f1519761700a117d58fec81982e","abstract_canon_sha256":"9ece23491f0c2d6953cf80c823ca8ecd303a3bba0a13d006239c593d233829a3"},"schema_version":"1.0"},"canonical_sha256":"fe5d7bf26d8c6b37c474f060f834c36d596f52d626bab9cdf25f7afb4c34762a","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-04T16:50:41.229353Z","signature_b64":"HuevSBVvA2egE38tWaGscddGwvFZkjlYmVqMGlij9B7Ya9+jKnasTK8J4626pwtjGnF6cLlZXELE7rcIJqSNBw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"fe5d7bf26d8c6b37c474f060f834c36d596f52d626bab9cdf25f7afb4c34762a","last_reissued_at":"2026-07-04T16:50:41.228993Z","signature_status":"signed_v1","first_computed_at":"2026-07-04T16:50:41.228993Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"astro-ph/0501489","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":"2026-07-04T16:50:41Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"E8p5vvavwugJ+l7LV2m9jL8TT6BVhO2EFLch2r3UBp16FaSbBDTtTVcMUmyuj/jpWYhJrnI/00UOiBIjwvc0Ag==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-06T08:04:09.716461Z"},"content_sha256":"2f6bbb3b7a8b74b0a23838098adb94217bdd0bf7fe61a12ffa9b891858177ad0","schema_version":"1.0","event_id":"sha256:2f6bbb3b7a8b74b0a23838098adb94217bdd0bf7fe61a12ffa9b891858177ad0"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2005:7ZOXX4TNRRVTPRDU6BQPQNGDNV","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Measuring Extinction Curves of Lensing Galaxies","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"Christina McGough, Geoffrey C. Clayton, Karl D. Gordon, & Michael J. Wolff","submitted_at":"2005-01-22T21:07:45Z","abstract_excerpt":"We critique the method of constructing extinction curves of lensing galaxies using multiply imaged QSOs. If one of the two QSO images is lightly reddened or if the dust along both sightlines has the same properties then the method works well and produces an extinction curve for the lensing galaxy. These cases are likely rare and hard to confirm. However, if the dust along each sightline has different properties then the resulting curve is no longer a measurement of extinction. Instead, it is a measurement of the difference between two extinction curves. This \"lens difference curve'' does conta"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0501489","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/0501489/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":"2026-07-04T16:50:41Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"sJ7djvo0sjX25Jv8pWrbAMaOnTwIxItESzAXgLbKPGLT1yT+3OdSQkuBd0hCm1M0OEcPwoQtBTRtQfCtTQYrBQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-06T08:04:09.717316Z"},"content_sha256":"07b55afb9f31680fe83506d8d83a3cc248b7018d30e2243ed62d890786ec5018","schema_version":"1.0","event_id":"sha256:07b55afb9f31680fe83506d8d83a3cc248b7018d30e2243ed62d890786ec5018"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/7ZOXX4TNRRVTPRDU6BQPQNGDNV/bundle.json","state_url":"https://pith.science/pith/7ZOXX4TNRRVTPRDU6BQPQNGDNV/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/7ZOXX4TNRRVTPRDU6BQPQNGDNV/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":"2026-08-06T08:04:09Z","links":{"resolver":"https://pith.science/pith/7ZOXX4TNRRVTPRDU6BQPQNGDNV","bundle":"https://pith.science/pith/7ZOXX4TNRRVTPRDU6BQPQNGDNV/bundle.json","state":"https://pith.science/pith/7ZOXX4TNRRVTPRDU6BQPQNGDNV/state.json","well_known_bundle":"https://pith.science/.well-known/pith/7ZOXX4TNRRVTPRDU6BQPQNGDNV/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2005:7ZOXX4TNRRVTPRDU6BQPQNGDNV","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":"9ece23491f0c2d6953cf80c823ca8ecd303a3bba0a13d006239c593d233829a3","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2005-01-22T21:07:45Z","title_canon_sha256":"45c63249c77595953812523739d31aca9c3a4f1519761700a117d58fec81982e"},"schema_version":"1.0","source":{"id":"astro-ph/0501489","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/0501489","created_at":"2026-07-04T16:50:41Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/0501489v1","created_at":"2026-07-04T16:50:41Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/0501489","created_at":"2026-07-04T16:50:41Z"},{"alias_kind":"pith_short_12","alias_value":"7ZOXX4TNRRVT","created_at":"2026-07-04T16:50:41Z"},{"alias_kind":"pith_short_16","alias_value":"7ZOXX4TNRRVTPRDU","created_at":"2026-07-04T16:50:41Z"},{"alias_kind":"pith_short_8","alias_value":"7ZOXX4TN","created_at":"2026-07-04T16:50:41Z"}],"graph_snapshots":[{"event_id":"sha256:07b55afb9f31680fe83506d8d83a3cc248b7018d30e2243ed62d890786ec5018","target":"graph","created_at":"2026-07-04T16:50:41Z","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/0501489/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"We critique the method of constructing extinction curves of lensing galaxies using multiply imaged QSOs. If one of the two QSO images is lightly reddened or if the dust along both sightlines has the same properties then the method works well and produces an extinction curve for the lensing galaxy. These cases are likely rare and hard to confirm. However, if the dust along each sightline has different properties then the resulting curve is no longer a measurement of extinction. Instead, it is a measurement of the difference between two extinction curves. This \"lens difference curve'' does conta","authors_text":"Christina McGough, Geoffrey C. Clayton, Karl D. Gordon, & Michael J. Wolff","cross_cats":[],"headline":"","license":"","primary_cat":"astro-ph","submitted_at":"2005-01-22T21:07:45Z","title":"Measuring Extinction Curves of Lensing Galaxies"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0501489","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":"sha256:2f6bbb3b7a8b74b0a23838098adb94217bdd0bf7fe61a12ffa9b891858177ad0","target":"record","created_at":"2026-07-04T16:50:41Z","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":"9ece23491f0c2d6953cf80c823ca8ecd303a3bba0a13d006239c593d233829a3","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2005-01-22T21:07:45Z","title_canon_sha256":"45c63249c77595953812523739d31aca9c3a4f1519761700a117d58fec81982e"},"schema_version":"1.0","source":{"id":"astro-ph/0501489","kind":"arxiv","version":1}},"canonical_sha256":"fe5d7bf26d8c6b37c474f060f834c36d596f52d626bab9cdf25f7afb4c34762a","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"fe5d7bf26d8c6b37c474f060f834c36d596f52d626bab9cdf25f7afb4c34762a","first_computed_at":"2026-07-04T16:50:41.228993Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T16:50:41.228993Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"HuevSBVvA2egE38tWaGscddGwvFZkjlYmVqMGlij9B7Ya9+jKnasTK8J4626pwtjGnF6cLlZXELE7rcIJqSNBw==","signature_status":"signed_v1","signed_at":"2026-07-04T16:50:41.229353Z","signed_message":"canonical_sha256_bytes"},"source_id":"astro-ph/0501489","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:2f6bbb3b7a8b74b0a23838098adb94217bdd0bf7fe61a12ffa9b891858177ad0","sha256:07b55afb9f31680fe83506d8d83a3cc248b7018d30e2243ed62d890786ec5018"],"state_sha256":"c84153ed99a0bd17947e19158552709975ae5ae9c663243692fd3f752733fbd6"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"SFqEHTUJBNtDDztu6VMyRnZNUAGBrdDEKRJjis+V/z/QQfliBPrTAtlS2fQzRN4nO4a8wEK+4asXOKICe3SpBA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-06T08:04:09.720781Z","bundle_sha256":"6a58bbcf3bbca87a58574d94c1245915b55254b22542fde0b4b08e9a08027033"}}