{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2006:VMH6TFKJWQNKNEURAY4E2TJGKI","short_pith_number":"pith:VMH6TFKJ","canonical_record":{"source":{"id":"astro-ph/0603742","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"2006-03-28T20:07:04Z","cross_cats_sorted":[],"title_canon_sha256":"a0fc2c06314a0d8a1d6ca7b8726825082a38f324d5389976e1369fdd707f3b50","abstract_canon_sha256":"8dfccd9a80f177bc42ef5b88801e56c6095728787ce68f210479dce17aa41b12"},"schema_version":"1.0"},"canonical_sha256":"ab0fe99549b41aa6929106384d4d2652106916808a6773ba2f29e364caed0818","source":{"kind":"arxiv","id":"astro-ph/0603742","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/0603742","created_at":"2026-05-18T04:29:04Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/0603742v2","created_at":"2026-05-18T04:29:04Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/0603742","created_at":"2026-05-18T04:29:04Z"},{"alias_kind":"pith_short_12","alias_value":"VMH6TFKJWQNK","created_at":"2026-05-18T12:25:54Z"},{"alias_kind":"pith_short_16","alias_value":"VMH6TFKJWQNKNEUR","created_at":"2026-05-18T12:25:54Z"},{"alias_kind":"pith_short_8","alias_value":"VMH6TFKJ","created_at":"2026-05-18T12:25:54Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2006:VMH6TFKJWQNKNEURAY4E2TJGKI","target":"record","payload":{"canonical_record":{"source":{"id":"astro-ph/0603742","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"2006-03-28T20:07:04Z","cross_cats_sorted":[],"title_canon_sha256":"a0fc2c06314a0d8a1d6ca7b8726825082a38f324d5389976e1369fdd707f3b50","abstract_canon_sha256":"8dfccd9a80f177bc42ef5b88801e56c6095728787ce68f210479dce17aa41b12"},"schema_version":"1.0"},"canonical_sha256":"ab0fe99549b41aa6929106384d4d2652106916808a6773ba2f29e364caed0818","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T04:29:04.889370Z","signature_b64":"osjn3R42RBcqAxBcZw/EbSB1zJavcjwm1XP1moBEqj3K3pdlbtCuI5yl+BeWcRXucmhAfc+Ev5oW6Y68e1jcAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"ab0fe99549b41aa6929106384d4d2652106916808a6773ba2f29e364caed0818","last_reissued_at":"2026-05-18T04:29:04.888888Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T04:29:04.888888Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"astro-ph/0603742","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T04:29:04Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Y3tYkAOJeNWxjPTY93GCODKCJTd+I4qJv28xMRoq+Pcsi160eUyi78EcFM+CVD+Rr2hZAfo17IsOZxfA8Y2XDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-26T21:23:41.455348Z"},"content_sha256":"ceead6699419bf49abf0f9957e942fb32b2f995ae12326be211c2b65da74f26b","schema_version":"1.0","event_id":"sha256:ceead6699419bf49abf0f9957e942fb32b2f995ae12326be211c2b65da74f26b"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2006:VMH6TFKJWQNKNEURAY4E2TJGKI","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Quasars Probing Quasars I: Optically Thick Absorbers Near Luminous Quasars","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"David J. Schlegel, Donald P. Schneider, Gordon T. Richards, James E. Gunn, Jason X. Prochaska, Jon Brinkmann, Joseph F. Hennawi, Masamune Oguri, Michael A. Strauss, Nadia L. Zakamska, Robert H. Lupton, Robert J. Brunner, Scott Burles, Xiaohui Fan","submitted_at":"2006-03-28T20:07:04Z","abstract_excerpt":"With close pairs of quasars at different redshifts, a background quasar sightline can be used to study a foreground quasar's environment in absorption. We search 149 moderate resolution background quasar spectra, from Gemini, Keck, the MMT, and the SDSS to survey Lyman Limit Systems (LLSs) and Damped Ly-alpha systems (DLAs) in the vicinity of 1.8 < z < 4.0 luminous foreground quasars. A sample of 27 new quasar-absorber pairs is uncovered with column densities, 17.2 < log (N_HI/cm^2) < 20.9, and transverse (proper) distances of 22 kpc/h < R < 1.7 Mpc/h, from the foreground quasars. If they emit"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0603742","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"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":"2026-05-18T04:29:04Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"NFbQdDFEQY+mvBX7ZeCvSnubgSz6TsBKoqNgGdX9fBBTmgpETB3IsPyv4iHDEWCsHMXE7zJpZ6ugjHuxRIOuAg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-26T21:23:41.455964Z"},"content_sha256":"9071152b94d7d5704981465543b9ad80cc8dc6df7b326d6a6390cf3d6e6991e0","schema_version":"1.0","event_id":"sha256:9071152b94d7d5704981465543b9ad80cc8dc6df7b326d6a6390cf3d6e6991e0"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/VMH6TFKJWQNKNEURAY4E2TJGKI/bundle.json","state_url":"https://pith.science/pith/VMH6TFKJWQNKNEURAY4E2TJGKI/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/VMH6TFKJWQNKNEURAY4E2TJGKI/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":"2026-05-26T21:23:41Z","links":{"resolver":"https://pith.science/pith/VMH6TFKJWQNKNEURAY4E2TJGKI","bundle":"https://pith.science/pith/VMH6TFKJWQNKNEURAY4E2TJGKI/bundle.json","state":"https://pith.science/pith/VMH6TFKJWQNKNEURAY4E2TJGKI/state.json","well_known_bundle":"https://pith.science/.well-known/pith/VMH6TFKJWQNKNEURAY4E2TJGKI/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2006:VMH6TFKJWQNKNEURAY4E2TJGKI","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":"8dfccd9a80f177bc42ef5b88801e56c6095728787ce68f210479dce17aa41b12","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2006-03-28T20:07:04Z","title_canon_sha256":"a0fc2c06314a0d8a1d6ca7b8726825082a38f324d5389976e1369fdd707f3b50"},"schema_version":"1.0","source":{"id":"astro-ph/0603742","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/0603742","created_at":"2026-05-18T04:29:04Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/0603742v2","created_at":"2026-05-18T04:29:04Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/0603742","created_at":"2026-05-18T04:29:04Z"},{"alias_kind":"pith_short_12","alias_value":"VMH6TFKJWQNK","created_at":"2026-05-18T12:25:54Z"},{"alias_kind":"pith_short_16","alias_value":"VMH6TFKJWQNKNEUR","created_at":"2026-05-18T12:25:54Z"},{"alias_kind":"pith_short_8","alias_value":"VMH6TFKJ","created_at":"2026-05-18T12:25:54Z"}],"graph_snapshots":[{"event_id":"sha256:9071152b94d7d5704981465543b9ad80cc8dc6df7b326d6a6390cf3d6e6991e0","target":"graph","created_at":"2026-05-18T04:29:04Z","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"},"paper":{"abstract_excerpt":"With close pairs of quasars at different redshifts, a background quasar sightline can be used to study a foreground quasar's environment in absorption. We search 149 moderate resolution background quasar spectra, from Gemini, Keck, the MMT, and the SDSS to survey Lyman Limit Systems (LLSs) and Damped Ly-alpha systems (DLAs) in the vicinity of 1.8 < z < 4.0 luminous foreground quasars. A sample of 27 new quasar-absorber pairs is uncovered with column densities, 17.2 < log (N_HI/cm^2) < 20.9, and transverse (proper) distances of 22 kpc/h < R < 1.7 Mpc/h, from the foreground quasars. If they emit","authors_text":"David J. Schlegel, Donald P. Schneider, Gordon T. Richards, James E. Gunn, Jason X. Prochaska, Jon Brinkmann, Joseph F. Hennawi, Masamune Oguri, Michael A. Strauss, Nadia L. Zakamska, Robert H. Lupton, Robert J. Brunner, Scott Burles, Xiaohui Fan","cross_cats":[],"headline":"","license":"","primary_cat":"astro-ph","submitted_at":"2006-03-28T20:07:04Z","title":"Quasars Probing Quasars I: Optically Thick Absorbers Near Luminous Quasars"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0603742","kind":"arxiv","version":2},"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:ceead6699419bf49abf0f9957e942fb32b2f995ae12326be211c2b65da74f26b","target":"record","created_at":"2026-05-18T04:29:04Z","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":"8dfccd9a80f177bc42ef5b88801e56c6095728787ce68f210479dce17aa41b12","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"2006-03-28T20:07:04Z","title_canon_sha256":"a0fc2c06314a0d8a1d6ca7b8726825082a38f324d5389976e1369fdd707f3b50"},"schema_version":"1.0","source":{"id":"astro-ph/0603742","kind":"arxiv","version":2}},"canonical_sha256":"ab0fe99549b41aa6929106384d4d2652106916808a6773ba2f29e364caed0818","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"ab0fe99549b41aa6929106384d4d2652106916808a6773ba2f29e364caed0818","first_computed_at":"2026-05-18T04:29:04.888888Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T04:29:04.888888Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"osjn3R42RBcqAxBcZw/EbSB1zJavcjwm1XP1moBEqj3K3pdlbtCuI5yl+BeWcRXucmhAfc+Ev5oW6Y68e1jcAA==","signature_status":"signed_v1","signed_at":"2026-05-18T04:29:04.889370Z","signed_message":"canonical_sha256_bytes"},"source_id":"astro-ph/0603742","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:ceead6699419bf49abf0f9957e942fb32b2f995ae12326be211c2b65da74f26b","sha256:9071152b94d7d5704981465543b9ad80cc8dc6df7b326d6a6390cf3d6e6991e0"],"state_sha256":"409d15ab37a2d1bb6e2d854c784e4d808f5efe834b8aeefb5f795aae368a661a"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"xx5AbvrMuMB5SdK72VMYXd5toGTbCNzdf8iF9y6bdy1c0fXy9kLHpXC2bOtLiVpNzOh141IYLT8dbIPQupO+Cw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-26T21:23:41.459153Z","bundle_sha256":"fc5dc6df4eb118b9efd66b168ebb2b2708c0828f5ed3fc62ad58f611e1a7963f"}}