{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:WXADWEME2GTKBPBPEMYW2YXKKS","short_pith_number":"pith:WXADWEME","canonical_record":{"source":{"id":"1801.06193","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-01-18T19:00:22Z","cross_cats_sorted":["astro-ph.CO"],"title_canon_sha256":"bc3eaf8dcb88a5f697336249ef8cccbe578a63dbc8c401410f0c131f3b0db139","abstract_canon_sha256":"2e7a6c6ceb9855434a0c0f0756a74d517aedf8e5a3d8c48b7abff6d88d2ace17"},"schema_version":"1.0"},"canonical_sha256":"b5c03b1184d1a6a0bc2f23316d62ea5499ae7ec5d5c0649dceedac85d9958959","source":{"kind":"arxiv","id":"1801.06193","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1801.06193","created_at":"2026-05-18T00:25:33Z"},{"alias_kind":"arxiv_version","alias_value":"1801.06193v1","created_at":"2026-05-18T00:25:33Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1801.06193","created_at":"2026-05-18T00:25:33Z"},{"alias_kind":"pith_short_12","alias_value":"WXADWEME2GTK","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_16","alias_value":"WXADWEME2GTKBPBP","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_8","alias_value":"WXADWEME","created_at":"2026-05-18T12:33:01Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:WXADWEME2GTKBPBPEMYW2YXKKS","target":"record","payload":{"canonical_record":{"source":{"id":"1801.06193","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-01-18T19:00:22Z","cross_cats_sorted":["astro-ph.CO"],"title_canon_sha256":"bc3eaf8dcb88a5f697336249ef8cccbe578a63dbc8c401410f0c131f3b0db139","abstract_canon_sha256":"2e7a6c6ceb9855434a0c0f0756a74d517aedf8e5a3d8c48b7abff6d88d2ace17"},"schema_version":"1.0"},"canonical_sha256":"b5c03b1184d1a6a0bc2f23316d62ea5499ae7ec5d5c0649dceedac85d9958959","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:25:33.232817Z","signature_b64":"7h1k1074irdhdrDq4TZH8cJ+Tq8dufiwJXMmaXjZAce/w1TrJEr6lp/NZSZPPXgOW9EkpfX7YQbd1iedyM5cAw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"b5c03b1184d1a6a0bc2f23316d62ea5499ae7ec5d5c0649dceedac85d9958959","last_reissued_at":"2026-05-18T00:25:33.232227Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:25:33.232227Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1801.06193","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":"2026-05-18T00:25:33Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"GJHTJyCrcDogZ65Gpz5eh4LhUkGM+zPF7P2nseuv0ie+hd90yUnByWAgoxpjAYXmDVdZdASlBFm8oLb0A34sAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-26T16:58:34.629187Z"},"content_sha256":"64ed8c7fa22c8773c1a0ee083f60c505f00cb3ec0893655ec5ef26ea68f43b7f","schema_version":"1.0","event_id":"sha256:64ed8c7fa22c8773c1a0ee083f60c505f00cb3ec0893655ec5ef26ea68f43b7f"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:WXADWEME2GTKBPBPEMYW2YXKKS","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Aligned metal absorbers and the ultraviolet background at the end of reionization","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.CO"],"primary_cat":"astro-ph.GA","authors_text":"Benjamin D. Oppenheimer, Caitlin Doughty, Erik Zackrisson, Kristian Finlator, Romeel Dav\\'e","submitted_at":"2018-01-18T19:00:22Z","abstract_excerpt":"We use observations of spatially-aligned C II, C IV, Si II, Si IV, and O I absorbers to probe the slope and intensity of the ultraviolet background (UVB) at $z \\sim 6$. We accomplish this by comparing observations with predictions from a cosmological hydrodynamic simulation using three trial UVBs applied in post-processing: a spectrally soft, fluctuating UVB calculated using multi-frequency radiative transfer; a soft, spatially-uniform UVB; and a hard, spatially-uniform \"quasars-only\" model. When considering our paired high-ionization absorbers (C IV/Si IV), the observed statistics strongly pr"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1801.06193","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":"2026-05-18T00:25:33Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"DCwSN+bvbqkvSYCe035b73P+CVg1S5Aa248TCNI/OJXQMz4oQwKa13cPB3oxsShDgPCnRiq2PyPvTwW1aCm1AA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-26T16:58:34.629849Z"},"content_sha256":"3b37a7a47ba28b1861e48e8225c79833f0dcbe845e2319bb14863fd25d606ff7","schema_version":"1.0","event_id":"sha256:3b37a7a47ba28b1861e48e8225c79833f0dcbe845e2319bb14863fd25d606ff7"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/WXADWEME2GTKBPBPEMYW2YXKKS/bundle.json","state_url":"https://pith.science/pith/WXADWEME2GTKBPBPEMYW2YXKKS/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/WXADWEME2GTKBPBPEMYW2YXKKS/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":"2026-05-26T16:58:34Z","links":{"resolver":"https://pith.science/pith/WXADWEME2GTKBPBPEMYW2YXKKS","bundle":"https://pith.science/pith/WXADWEME2GTKBPBPEMYW2YXKKS/bundle.json","state":"https://pith.science/pith/WXADWEME2GTKBPBPEMYW2YXKKS/state.json","well_known_bundle":"https://pith.science/.well-known/pith/WXADWEME2GTKBPBPEMYW2YXKKS/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:WXADWEME2GTKBPBPEMYW2YXKKS","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":"2e7a6c6ceb9855434a0c0f0756a74d517aedf8e5a3d8c48b7abff6d88d2ace17","cross_cats_sorted":["astro-ph.CO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-01-18T19:00:22Z","title_canon_sha256":"bc3eaf8dcb88a5f697336249ef8cccbe578a63dbc8c401410f0c131f3b0db139"},"schema_version":"1.0","source":{"id":"1801.06193","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1801.06193","created_at":"2026-05-18T00:25:33Z"},{"alias_kind":"arxiv_version","alias_value":"1801.06193v1","created_at":"2026-05-18T00:25:33Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1801.06193","created_at":"2026-05-18T00:25:33Z"},{"alias_kind":"pith_short_12","alias_value":"WXADWEME2GTK","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_16","alias_value":"WXADWEME2GTKBPBP","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_8","alias_value":"WXADWEME","created_at":"2026-05-18T12:33:01Z"}],"graph_snapshots":[{"event_id":"sha256:3b37a7a47ba28b1861e48e8225c79833f0dcbe845e2319bb14863fd25d606ff7","target":"graph","created_at":"2026-05-18T00:25:33Z","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 use observations of spatially-aligned C II, C IV, Si II, Si IV, and O I absorbers to probe the slope and intensity of the ultraviolet background (UVB) at $z \\sim 6$. We accomplish this by comparing observations with predictions from a cosmological hydrodynamic simulation using three trial UVBs applied in post-processing: a spectrally soft, fluctuating UVB calculated using multi-frequency radiative transfer; a soft, spatially-uniform UVB; and a hard, spatially-uniform \"quasars-only\" model. When considering our paired high-ionization absorbers (C IV/Si IV), the observed statistics strongly pr","authors_text":"Benjamin D. Oppenheimer, Caitlin Doughty, Erik Zackrisson, Kristian Finlator, Romeel Dav\\'e","cross_cats":["astro-ph.CO"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-01-18T19:00:22Z","title":"Aligned metal absorbers and the ultraviolet background at the end of reionization"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1801.06193","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":"sha256:64ed8c7fa22c8773c1a0ee083f60c505f00cb3ec0893655ec5ef26ea68f43b7f","target":"record","created_at":"2026-05-18T00:25:33Z","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":"2e7a6c6ceb9855434a0c0f0756a74d517aedf8e5a3d8c48b7abff6d88d2ace17","cross_cats_sorted":["astro-ph.CO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-01-18T19:00:22Z","title_canon_sha256":"bc3eaf8dcb88a5f697336249ef8cccbe578a63dbc8c401410f0c131f3b0db139"},"schema_version":"1.0","source":{"id":"1801.06193","kind":"arxiv","version":1}},"canonical_sha256":"b5c03b1184d1a6a0bc2f23316d62ea5499ae7ec5d5c0649dceedac85d9958959","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"b5c03b1184d1a6a0bc2f23316d62ea5499ae7ec5d5c0649dceedac85d9958959","first_computed_at":"2026-05-18T00:25:33.232227Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:25:33.232227Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"7h1k1074irdhdrDq4TZH8cJ+Tq8dufiwJXMmaXjZAce/w1TrJEr6lp/NZSZPPXgOW9EkpfX7YQbd1iedyM5cAw==","signature_status":"signed_v1","signed_at":"2026-05-18T00:25:33.232817Z","signed_message":"canonical_sha256_bytes"},"source_id":"1801.06193","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:64ed8c7fa22c8773c1a0ee083f60c505f00cb3ec0893655ec5ef26ea68f43b7f","sha256:3b37a7a47ba28b1861e48e8225c79833f0dcbe845e2319bb14863fd25d606ff7"],"state_sha256":"6f126095f10b1956e363e1e3f9a765b8d680414ca67c4fe549dd6d235241a6d4"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"KSMESPIbsdDPRPpAkq/rCBgLMdQceEEiKOlaNrg8r/diciR0W02gDzWs9o0AFtDvEKFEiBg8iAnd1rpv5IqpCw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-26T16:58:34.633509Z","bundle_sha256":"ff0efda1fb33ef9a40e298f0f4b6ee49cd58c0b3084798404a93d8d182da5946"}}