{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2017:KSOLV3SY4KWSKD4COXKPDO35EK","short_pith_number":"pith:KSOLV3SY","canonical_record":{"source":{"id":"1702.03937","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-02-13T19:00:06Z","cross_cats_sorted":["astro-ph.CO"],"title_canon_sha256":"2a3e91a6e4e78f8b193a2d4ab5ec044be7c67768c3e65bd5074c53d5ff0559da","abstract_canon_sha256":"79110d9b447fcc9df66145c63ecc6e6dacdf2329473a8c31218525c919b4217d"},"schema_version":"1.0"},"canonical_sha256":"549cbaee58e2ad250f8275d4f1bb7d228e4cc0a9fd2f65d75da17b3512c12a8e","source":{"kind":"arxiv","id":"1702.03937","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1702.03937","created_at":"2026-05-18T00:24:31Z"},{"alias_kind":"arxiv_version","alias_value":"1702.03937v2","created_at":"2026-05-18T00:24:31Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1702.03937","created_at":"2026-05-18T00:24:31Z"},{"alias_kind":"pith_short_12","alias_value":"KSOLV3SY4KWS","created_at":"2026-05-18T12:31:28Z"},{"alias_kind":"pith_short_16","alias_value":"KSOLV3SY4KWSKD4C","created_at":"2026-05-18T12:31:28Z"},{"alias_kind":"pith_short_8","alias_value":"KSOLV3SY","created_at":"2026-05-18T12:31:28Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2017:KSOLV3SY4KWSKD4COXKPDO35EK","target":"record","payload":{"canonical_record":{"source":{"id":"1702.03937","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-02-13T19:00:06Z","cross_cats_sorted":["astro-ph.CO"],"title_canon_sha256":"2a3e91a6e4e78f8b193a2d4ab5ec044be7c67768c3e65bd5074c53d5ff0559da","abstract_canon_sha256":"79110d9b447fcc9df66145c63ecc6e6dacdf2329473a8c31218525c919b4217d"},"schema_version":"1.0"},"canonical_sha256":"549cbaee58e2ad250f8275d4f1bb7d228e4cc0a9fd2f65d75da17b3512c12a8e","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:24:31.526111Z","signature_b64":"HvKH/dlYwban/MJbjVOdFO8kQnXRtOl1jjAKHTmeBxjN7dOUDy98KHOjFIfuO8AnqRP3KxGToAxOvbwRl4jLDQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"549cbaee58e2ad250f8275d4f1bb7d228e4cc0a9fd2f65d75da17b3512c12a8e","last_reissued_at":"2026-05-18T00:24:31.525485Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:24:31.525485Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1702.03937","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":"2026-05-18T00:24:31Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"SK5U0LoOiguw2WCfmaPQiqUrlDDukIzoKombYDU7X9sp46995ZLwx6RjNzvBFKTiovIADT7Z59Q3OnWHR90YBA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-14T06:41:12.293206Z"},"content_sha256":"ceebc41a713d5efd28d9d222c36febf7ad527fdf8f5ca259a1a18a0240d8cfc1","schema_version":"1.0","event_id":"sha256:ceebc41a713d5efd28d9d222c36febf7ad527fdf8f5ca259a1a18a0240d8cfc1"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2017:KSOLV3SY4KWSKD4COXKPDO35EK","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Constraints on QSO emissivity using H I and He II Lyman alpha forest","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.CO"],"primary_cat":"astro-ph.GA","authors_text":"Vikram Khaire","submitted_at":"2017-02-13T19:00:06Z","abstract_excerpt":"The spectrum of cosmic ultraviolet background radiation at He II ionizing energies (E > 4 Ryd) is important to study the He II reionization, thermal history of the intergalactic medium (IGM) and metal lines observed in QSO absorption spectra. It is determined by the emissivity of QSOs at E > 4 Ryd obtained from their observed luminosity functions and the mean spectral energy distribution (SED). The SED is approximated as a power-law at energies E > 1 Ryd, $f_E \\propto E^{\\alpha}$, where the existing observations constrain the power-law index $\\alpha$ only up to ~2.3 Ryd. Here, we constrain $\\a"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1702.03937","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":"2026-05-18T00:24:31Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"RYw0yms9J2kTai68coEkUrlMqHriwz3lhDXi2k1rC8Y/n3EggPJCboTIhmxYjN3OKkxJlWUgzjtBZSolB7kpCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-14T06:41:12.293897Z"},"content_sha256":"fd34fc6268ad66dd11b29af587f091c8fac837da45528430f0c50efabc93d350","schema_version":"1.0","event_id":"sha256:fd34fc6268ad66dd11b29af587f091c8fac837da45528430f0c50efabc93d350"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/KSOLV3SY4KWSKD4COXKPDO35EK/bundle.json","state_url":"https://pith.science/pith/KSOLV3SY4KWSKD4COXKPDO35EK/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/KSOLV3SY4KWSKD4COXKPDO35EK/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":"2026-08-14T06:41:12Z","links":{"resolver":"https://pith.science/pith/KSOLV3SY4KWSKD4COXKPDO35EK","bundle":"https://pith.science/pith/KSOLV3SY4KWSKD4COXKPDO35EK/bundle.json","state":"https://pith.science/pith/KSOLV3SY4KWSKD4COXKPDO35EK/state.json","well_known_bundle":"https://pith.science/.well-known/pith/KSOLV3SY4KWSKD4COXKPDO35EK/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2017:KSOLV3SY4KWSKD4COXKPDO35EK","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":"79110d9b447fcc9df66145c63ecc6e6dacdf2329473a8c31218525c919b4217d","cross_cats_sorted":["astro-ph.CO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-02-13T19:00:06Z","title_canon_sha256":"2a3e91a6e4e78f8b193a2d4ab5ec044be7c67768c3e65bd5074c53d5ff0559da"},"schema_version":"1.0","source":{"id":"1702.03937","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1702.03937","created_at":"2026-05-18T00:24:31Z"},{"alias_kind":"arxiv_version","alias_value":"1702.03937v2","created_at":"2026-05-18T00:24:31Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1702.03937","created_at":"2026-05-18T00:24:31Z"},{"alias_kind":"pith_short_12","alias_value":"KSOLV3SY4KWS","created_at":"2026-05-18T12:31:28Z"},{"alias_kind":"pith_short_16","alias_value":"KSOLV3SY4KWSKD4C","created_at":"2026-05-18T12:31:28Z"},{"alias_kind":"pith_short_8","alias_value":"KSOLV3SY","created_at":"2026-05-18T12:31:28Z"}],"graph_snapshots":[{"event_id":"sha256:fd34fc6268ad66dd11b29af587f091c8fac837da45528430f0c50efabc93d350","target":"graph","created_at":"2026-05-18T00:24:31Z","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":"The spectrum of cosmic ultraviolet background radiation at He II ionizing energies (E > 4 Ryd) is important to study the He II reionization, thermal history of the intergalactic medium (IGM) and metal lines observed in QSO absorption spectra. It is determined by the emissivity of QSOs at E > 4 Ryd obtained from their observed luminosity functions and the mean spectral energy distribution (SED). The SED is approximated as a power-law at energies E > 1 Ryd, $f_E \\propto E^{\\alpha}$, where the existing observations constrain the power-law index $\\alpha$ only up to ~2.3 Ryd. Here, we constrain $\\a","authors_text":"Vikram Khaire","cross_cats":["astro-ph.CO"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-02-13T19:00:06Z","title":"Constraints on QSO emissivity using H I and He II Lyman alpha forest"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1702.03937","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:ceebc41a713d5efd28d9d222c36febf7ad527fdf8f5ca259a1a18a0240d8cfc1","target":"record","created_at":"2026-05-18T00:24:31Z","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":"79110d9b447fcc9df66145c63ecc6e6dacdf2329473a8c31218525c919b4217d","cross_cats_sorted":["astro-ph.CO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-02-13T19:00:06Z","title_canon_sha256":"2a3e91a6e4e78f8b193a2d4ab5ec044be7c67768c3e65bd5074c53d5ff0559da"},"schema_version":"1.0","source":{"id":"1702.03937","kind":"arxiv","version":2}},"canonical_sha256":"549cbaee58e2ad250f8275d4f1bb7d228e4cc0a9fd2f65d75da17b3512c12a8e","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"549cbaee58e2ad250f8275d4f1bb7d228e4cc0a9fd2f65d75da17b3512c12a8e","first_computed_at":"2026-05-18T00:24:31.525485Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:24:31.525485Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"HvKH/dlYwban/MJbjVOdFO8kQnXRtOl1jjAKHTmeBxjN7dOUDy98KHOjFIfuO8AnqRP3KxGToAxOvbwRl4jLDQ==","signature_status":"signed_v1","signed_at":"2026-05-18T00:24:31.526111Z","signed_message":"canonical_sha256_bytes"},"source_id":"1702.03937","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:ceebc41a713d5efd28d9d222c36febf7ad527fdf8f5ca259a1a18a0240d8cfc1","sha256:fd34fc6268ad66dd11b29af587f091c8fac837da45528430f0c50efabc93d350"],"state_sha256":"55f3524bd6d66edce054740f4047ca4b7cf52f45ff97a9fd1ca7e79beae426ec"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"J/2zMxABiSIaEJYjrbO2Iy2FSGrJXoqUCJBcj4q+sSNGM0gDbS4nEbOL+OYFf/G52VDAFN1Qh1fTFl3ELWitBA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-14T06:41:12.300566Z","bundle_sha256":"ada9bf400586dbb0877c48bacf575092160142efb6a69da563e360704b3a1614"}}