{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2012:DVK46HYJWWUJPD6ZOXBCV6DB6C","short_pith_number":"pith:DVK46HYJ","canonical_record":{"source":{"id":"1201.3919","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-01-18T21:00:04Z","cross_cats_sorted":[],"title_canon_sha256":"d3d208ed7fe0d11c41bfeeb2318b8f1a79f2eca0a078c411498f060b55dc37c5","abstract_canon_sha256":"89b2dc8323e440cef0c26f79dd97634a92524cb7244fed89e953395b51cb2cf4"},"schema_version":"1.0"},"canonical_sha256":"1d55cf1f09b5a8978fd975c22af861f094758a8bf3c89fdd2d21456ee8c85929","source":{"kind":"arxiv","id":"1201.3919","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1201.3919","created_at":"2026-05-18T01:58:47Z"},{"alias_kind":"arxiv_version","alias_value":"1201.3919v1","created_at":"2026-05-18T01:58:47Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1201.3919","created_at":"2026-05-18T01:58:47Z"},{"alias_kind":"pith_short_12","alias_value":"DVK46HYJWWUJ","created_at":"2026-05-18T12:27:04Z"},{"alias_kind":"pith_short_16","alias_value":"DVK46HYJWWUJPD6Z","created_at":"2026-05-18T12:27:04Z"},{"alias_kind":"pith_short_8","alias_value":"DVK46HYJ","created_at":"2026-05-18T12:27:04Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2012:DVK46HYJWWUJPD6ZOXBCV6DB6C","target":"record","payload":{"canonical_record":{"source":{"id":"1201.3919","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-01-18T21:00:04Z","cross_cats_sorted":[],"title_canon_sha256":"d3d208ed7fe0d11c41bfeeb2318b8f1a79f2eca0a078c411498f060b55dc37c5","abstract_canon_sha256":"89b2dc8323e440cef0c26f79dd97634a92524cb7244fed89e953395b51cb2cf4"},"schema_version":"1.0"},"canonical_sha256":"1d55cf1f09b5a8978fd975c22af861f094758a8bf3c89fdd2d21456ee8c85929","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:58:47.134910Z","signature_b64":"r0zsuU4w2SEuTKtVIyEMcK7xTCVlRJ3j0CojN3uBQJPpO0/r9iRiXm7okyOyUH7l4iELG86fwlRsscfZIo5MAg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"1d55cf1f09b5a8978fd975c22af861f094758a8bf3c89fdd2d21456ee8c85929","last_reissued_at":"2026-05-18T01:58:47.134219Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:58:47.134219Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1201.3919","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":"2026-05-18T01:58:47Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"sZYhBv1Rw19/6pc89xmBhvHZ+4SR9xZntRq0acaaS0dyNzL5J+Egy/dw9wo+ymlzEJKutGfvMPTWupowcwQLCg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-22T12:07:16.453848Z"},"content_sha256":"30fa94d15f854889e1a0a12daf2ec33f37fb21cfb61e0772e0ac39fbaaf8f82d","schema_version":"1.0","event_id":"sha256:30fa94d15f854889e1a0a12daf2ec33f37fb21cfb61e0772e0ac39fbaaf8f82d"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2012:DVK46HYJWWUJPD6ZOXBCV6DB6C","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"A Survey of MgII Absorption at 2 < z < 6 with Magellan / FIRE: I: Sample and Evolution of the MgII Frequency","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"Michael S. Matejek, Robert A. Simcoe (MIT)","submitted_at":"2012-01-18T21:00:04Z","abstract_excerpt":"We present initial results from the first systematic survey for MgII quasar absorption lines at z > 2.5. Using infrared spectra of 46 high-redshift quasars, we discovered 111 MgII systems over a path covering 1.9 < z < 6.3. Five systems have z > 5, with a maximum of z = 5.33 - the most distant MgII system now known. The comoving MgII line density for weaker systems (Wr < 1.0A) is statistically consistent with no evolution from z = 0.4 to z = 5.5, while that for stronger systems increases three-fold until z \\sim 3 before declining again towards higher redshifts. The equivalent width distributio"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1201.3919","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":""},"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":"2026-05-18T01:58:47Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"H2dJeUeS6BVykk3f/5OwFWTmmbNrldl1QEekZibf7BGCC9mLtI9gSqfC64rTfay9zQI7GeGvYO35b61yWd+MBA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-22T12:07:16.454264Z"},"content_sha256":"7b3ebd31c697c7910bc6c79e7bec5da25922a0732f55da81964c5f34ed334004","schema_version":"1.0","event_id":"sha256:7b3ebd31c697c7910bc6c79e7bec5da25922a0732f55da81964c5f34ed334004"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/DVK46HYJWWUJPD6ZOXBCV6DB6C/bundle.json","state_url":"https://pith.science/pith/DVK46HYJWWUJPD6ZOXBCV6DB6C/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/DVK46HYJWWUJPD6ZOXBCV6DB6C/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":"2026-05-22T12:07:16Z","links":{"resolver":"https://pith.science/pith/DVK46HYJWWUJPD6ZOXBCV6DB6C","bundle":"https://pith.science/pith/DVK46HYJWWUJPD6ZOXBCV6DB6C/bundle.json","state":"https://pith.science/pith/DVK46HYJWWUJPD6ZOXBCV6DB6C/state.json","well_known_bundle":"https://pith.science/.well-known/pith/DVK46HYJWWUJPD6ZOXBCV6DB6C/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2012:DVK46HYJWWUJPD6ZOXBCV6DB6C","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":"89b2dc8323e440cef0c26f79dd97634a92524cb7244fed89e953395b51cb2cf4","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-01-18T21:00:04Z","title_canon_sha256":"d3d208ed7fe0d11c41bfeeb2318b8f1a79f2eca0a078c411498f060b55dc37c5"},"schema_version":"1.0","source":{"id":"1201.3919","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1201.3919","created_at":"2026-05-18T01:58:47Z"},{"alias_kind":"arxiv_version","alias_value":"1201.3919v1","created_at":"2026-05-18T01:58:47Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1201.3919","created_at":"2026-05-18T01:58:47Z"},{"alias_kind":"pith_short_12","alias_value":"DVK46HYJWWUJ","created_at":"2026-05-18T12:27:04Z"},{"alias_kind":"pith_short_16","alias_value":"DVK46HYJWWUJPD6Z","created_at":"2026-05-18T12:27:04Z"},{"alias_kind":"pith_short_8","alias_value":"DVK46HYJ","created_at":"2026-05-18T12:27:04Z"}],"graph_snapshots":[{"event_id":"sha256:7b3ebd31c697c7910bc6c79e7bec5da25922a0732f55da81964c5f34ed334004","target":"graph","created_at":"2026-05-18T01:58:47Z","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":"We present initial results from the first systematic survey for MgII quasar absorption lines at z > 2.5. Using infrared spectra of 46 high-redshift quasars, we discovered 111 MgII systems over a path covering 1.9 < z < 6.3. Five systems have z > 5, with a maximum of z = 5.33 - the most distant MgII system now known. The comoving MgII line density for weaker systems (Wr < 1.0A) is statistically consistent with no evolution from z = 0.4 to z = 5.5, while that for stronger systems increases three-fold until z \\sim 3 before declining again towards higher redshifts. The equivalent width distributio","authors_text":"Michael S. Matejek, Robert A. Simcoe (MIT)","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-01-18T21:00:04Z","title":"A Survey of MgII Absorption at 2 < z < 6 with Magellan / FIRE: I: Sample and Evolution of the MgII Frequency"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1201.3919","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":"sha256:30fa94d15f854889e1a0a12daf2ec33f37fb21cfb61e0772e0ac39fbaaf8f82d","target":"record","created_at":"2026-05-18T01:58:47Z","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":"89b2dc8323e440cef0c26f79dd97634a92524cb7244fed89e953395b51cb2cf4","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-01-18T21:00:04Z","title_canon_sha256":"d3d208ed7fe0d11c41bfeeb2318b8f1a79f2eca0a078c411498f060b55dc37c5"},"schema_version":"1.0","source":{"id":"1201.3919","kind":"arxiv","version":1}},"canonical_sha256":"1d55cf1f09b5a8978fd975c22af861f094758a8bf3c89fdd2d21456ee8c85929","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"1d55cf1f09b5a8978fd975c22af861f094758a8bf3c89fdd2d21456ee8c85929","first_computed_at":"2026-05-18T01:58:47.134219Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:58:47.134219Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"r0zsuU4w2SEuTKtVIyEMcK7xTCVlRJ3j0CojN3uBQJPpO0/r9iRiXm7okyOyUH7l4iELG86fwlRsscfZIo5MAg==","signature_status":"signed_v1","signed_at":"2026-05-18T01:58:47.134910Z","signed_message":"canonical_sha256_bytes"},"source_id":"1201.3919","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:30fa94d15f854889e1a0a12daf2ec33f37fb21cfb61e0772e0ac39fbaaf8f82d","sha256:7b3ebd31c697c7910bc6c79e7bec5da25922a0732f55da81964c5f34ed334004"],"state_sha256":"a2b1dede25e945d5ec812f6597a5aefd74f1e6e651bcb38395a9ffb7dc809186"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"JFVqFhGhjH81URUEonaGm6vf/5KgD5OF05NKPPx+mRkT2khyyURZwtflyODn5BMlejp5+3H4/rujnzp1jCDYAw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-22T12:07:16.456905Z","bundle_sha256":"6b4ccb4aa319fd8b9ddbf592e36e569c034c7e14f30764dc8d639db0ce0187d3"}}