{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2013:UV57BBJKMK3VUQB22ZAJERCZTD","short_pith_number":"pith:UV57BBJK","canonical_record":{"source":{"id":"1303.1000","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2013-03-05T12:03:57Z","cross_cats_sorted":[],"title_canon_sha256":"087e9a14f996ecffa7b4b912107f76287c379b190db7d2ed1b97b0fc40949b66","abstract_canon_sha256":"d2e55bb8020fc171e5140604cf6850763a74461d24989765e32ebd09abb11e70"},"schema_version":"1.0"},"canonical_sha256":"a57bf0852a62b75a403ad64092445998c3bf2cd4a9b8ae705aaa3885919fc005","source":{"kind":"arxiv","id":"1303.1000","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1303.1000","created_at":"2026-05-18T01:51:16Z"},{"alias_kind":"arxiv_version","alias_value":"1303.1000v1","created_at":"2026-05-18T01:51:16Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1303.1000","created_at":"2026-05-18T01:51:16Z"},{"alias_kind":"pith_short_12","alias_value":"UV57BBJKMK3V","created_at":"2026-05-18T12:28:02Z"},{"alias_kind":"pith_short_16","alias_value":"UV57BBJKMK3VUQB2","created_at":"2026-05-18T12:28:02Z"},{"alias_kind":"pith_short_8","alias_value":"UV57BBJK","created_at":"2026-05-18T12:28:02Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2013:UV57BBJKMK3VUQB22ZAJERCZTD","target":"record","payload":{"canonical_record":{"source":{"id":"1303.1000","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2013-03-05T12:03:57Z","cross_cats_sorted":[],"title_canon_sha256":"087e9a14f996ecffa7b4b912107f76287c379b190db7d2ed1b97b0fc40949b66","abstract_canon_sha256":"d2e55bb8020fc171e5140604cf6850763a74461d24989765e32ebd09abb11e70"},"schema_version":"1.0"},"canonical_sha256":"a57bf0852a62b75a403ad64092445998c3bf2cd4a9b8ae705aaa3885919fc005","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:51:16.889295Z","signature_b64":"HiVu5gxKX6Gv8Nalin0iLZgQuy/8b/PDLW85bCInku1/qHVZPBTjNo8eDoJRooIrbPaYwzaYAm8OPw90SbUXBQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"a57bf0852a62b75a403ad64092445998c3bf2cd4a9b8ae705aaa3885919fc005","last_reissued_at":"2026-05-18T01:51:16.888757Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:51:16.888757Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1303.1000","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":"2026-05-18T01:51:16Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"9I+bblza+uuY3vPHR0c+hbQ2RaVhIfLYjatZm8pzC0qH3OJbBWj5MyRhmz7ld7KgIH5PVfJxg2JvW++ixRb9Aw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-08T08:10:09.655544Z"},"content_sha256":"2e75bc27ab95221d62597e4a10e69d9d3740cb2d5c7bdc281706effd2bd20c13","schema_version":"1.0","event_id":"sha256:2e75bc27ab95221d62597e4a10e69d9d3740cb2d5c7bdc281706effd2bd20c13"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2013:UV57BBJKMK3VUQB22ZAJERCZTD","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Fluctuations of the intergalactic ionization field at redshift z ~ 2","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"D. Reimers, D. Tytler, H.-J. Hagen, I. I. Agafonova, S. A. Levshakov","submitted_at":"2013-03-05T12:03:57Z","abstract_excerpt":"(Abridged) Aims. To probe the spectral energy distribution (SED) of the ionizing background radiation at z ~ 2 and to specify the sources contributing to the intergalactic radiation field. Methods. The spectrum of a bright quasar HS1103+6416 (zem = 2.19) contains five successive metal-line absorption systems at zabs = 1.1923, 1.7193, 1.8873, 1.8916, and 1.9410. The systems are optically thin and reveal multiple lines of different metal ions with the ionization potentials lying in the extreme ultraviolet (EUV) range (1 Ryd to 0.2 keV). For each system, the EUV SED of the underlying ionization f"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1303.1000","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":"2026-05-18T01:51:16Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"88DNzEzbbVYg+5aXJFYddrMXMMLVkPTR++Jkw4oQ2IuLmDYS0h9xlaYGXHp/uZMLyitYZGgb1/YSJAbGS2pNDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-08T08:10:09.656166Z"},"content_sha256":"b8426ec75aedbc364f4028d524e735effe94974875f811d132651296199f2942","schema_version":"1.0","event_id":"sha256:b8426ec75aedbc364f4028d524e735effe94974875f811d132651296199f2942"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/UV57BBJKMK3VUQB22ZAJERCZTD/bundle.json","state_url":"https://pith.science/pith/UV57BBJKMK3VUQB22ZAJERCZTD/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/UV57BBJKMK3VUQB22ZAJERCZTD/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":"2026-06-08T08:10:09Z","links":{"resolver":"https://pith.science/pith/UV57BBJKMK3VUQB22ZAJERCZTD","bundle":"https://pith.science/pith/UV57BBJKMK3VUQB22ZAJERCZTD/bundle.json","state":"https://pith.science/pith/UV57BBJKMK3VUQB22ZAJERCZTD/state.json","well_known_bundle":"https://pith.science/.well-known/pith/UV57BBJKMK3VUQB22ZAJERCZTD/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2013:UV57BBJKMK3VUQB22ZAJERCZTD","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":"d2e55bb8020fc171e5140604cf6850763a74461d24989765e32ebd09abb11e70","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2013-03-05T12:03:57Z","title_canon_sha256":"087e9a14f996ecffa7b4b912107f76287c379b190db7d2ed1b97b0fc40949b66"},"schema_version":"1.0","source":{"id":"1303.1000","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1303.1000","created_at":"2026-05-18T01:51:16Z"},{"alias_kind":"arxiv_version","alias_value":"1303.1000v1","created_at":"2026-05-18T01:51:16Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1303.1000","created_at":"2026-05-18T01:51:16Z"},{"alias_kind":"pith_short_12","alias_value":"UV57BBJKMK3V","created_at":"2026-05-18T12:28:02Z"},{"alias_kind":"pith_short_16","alias_value":"UV57BBJKMK3VUQB2","created_at":"2026-05-18T12:28:02Z"},{"alias_kind":"pith_short_8","alias_value":"UV57BBJK","created_at":"2026-05-18T12:28:02Z"}],"graph_snapshots":[{"event_id":"sha256:b8426ec75aedbc364f4028d524e735effe94974875f811d132651296199f2942","target":"graph","created_at":"2026-05-18T01:51:16Z","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":"(Abridged) Aims. To probe the spectral energy distribution (SED) of the ionizing background radiation at z ~ 2 and to specify the sources contributing to the intergalactic radiation field. Methods. The spectrum of a bright quasar HS1103+6416 (zem = 2.19) contains five successive metal-line absorption systems at zabs = 1.1923, 1.7193, 1.8873, 1.8916, and 1.9410. The systems are optically thin and reveal multiple lines of different metal ions with the ionization potentials lying in the extreme ultraviolet (EUV) range (1 Ryd to 0.2 keV). For each system, the EUV SED of the underlying ionization f","authors_text":"D. Reimers, D. Tytler, H.-J. Hagen, I. I. Agafonova, S. A. Levshakov","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2013-03-05T12:03:57Z","title":"Fluctuations of the intergalactic ionization field at redshift z ~ 2"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1303.1000","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":"sha256:2e75bc27ab95221d62597e4a10e69d9d3740cb2d5c7bdc281706effd2bd20c13","target":"record","created_at":"2026-05-18T01:51:16Z","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":"d2e55bb8020fc171e5140604cf6850763a74461d24989765e32ebd09abb11e70","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2013-03-05T12:03:57Z","title_canon_sha256":"087e9a14f996ecffa7b4b912107f76287c379b190db7d2ed1b97b0fc40949b66"},"schema_version":"1.0","source":{"id":"1303.1000","kind":"arxiv","version":1}},"canonical_sha256":"a57bf0852a62b75a403ad64092445998c3bf2cd4a9b8ae705aaa3885919fc005","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"a57bf0852a62b75a403ad64092445998c3bf2cd4a9b8ae705aaa3885919fc005","first_computed_at":"2026-05-18T01:51:16.888757Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:51:16.888757Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"HiVu5gxKX6Gv8Nalin0iLZgQuy/8b/PDLW85bCInku1/qHVZPBTjNo8eDoJRooIrbPaYwzaYAm8OPw90SbUXBQ==","signature_status":"signed_v1","signed_at":"2026-05-18T01:51:16.889295Z","signed_message":"canonical_sha256_bytes"},"source_id":"1303.1000","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:2e75bc27ab95221d62597e4a10e69d9d3740cb2d5c7bdc281706effd2bd20c13","sha256:b8426ec75aedbc364f4028d524e735effe94974875f811d132651296199f2942"],"state_sha256":"a3cd8c34d26748ff6d644c5855d7dfd6e5eb7eb347dd58f1768ef688f4303ebf"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"OHQaJaTDv/fX+jCwzOX3Xof4sgsNmMmVoEO3gMMzT0CzDTq4f94YMFUozESV/EuUclvCS9vj/0KhVw15EZFQBQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-08T08:10:09.659968Z","bundle_sha256":"238de83393f639991896743b73e84c24aa8a5d6bffe6e0b3a8b1a8cfcade35b7"}}