{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2017:YCZKCY7U7WPNU5JTMJ33J5VQGK","short_pith_number":"pith:YCZKCY7U","canonical_record":{"source":{"id":"1712.07515","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-12-20T15:08:40Z","cross_cats_sorted":["astro-ph.CO"],"title_canon_sha256":"3eeb662443541ec24a73c3cd777c7d6516c14c62ad477d346b68323265ecbb12","abstract_canon_sha256":"28aaf3bf74ee5f135a2d69864f4d34a5896abd6e8b03ebdd44a537e84aaba96c"},"schema_version":"1.0"},"canonical_sha256":"c0b2a163f4fd9eda75336277b4f6b032889b6f8d165c4eb3b511f5fd93c48201","source":{"kind":"arxiv","id":"1712.07515","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1712.07515","created_at":"2026-05-18T00:27:34Z"},{"alias_kind":"arxiv_version","alias_value":"1712.07515v1","created_at":"2026-05-18T00:27:34Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1712.07515","created_at":"2026-05-18T00:27:34Z"},{"alias_kind":"pith_short_12","alias_value":"YCZKCY7U7WPN","created_at":"2026-05-18T12:31:56Z"},{"alias_kind":"pith_short_16","alias_value":"YCZKCY7U7WPNU5JT","created_at":"2026-05-18T12:31:56Z"},{"alias_kind":"pith_short_8","alias_value":"YCZKCY7U","created_at":"2026-05-18T12:31:56Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2017:YCZKCY7U7WPNU5JTMJ33J5VQGK","target":"record","payload":{"canonical_record":{"source":{"id":"1712.07515","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-12-20T15:08:40Z","cross_cats_sorted":["astro-ph.CO"],"title_canon_sha256":"3eeb662443541ec24a73c3cd777c7d6516c14c62ad477d346b68323265ecbb12","abstract_canon_sha256":"28aaf3bf74ee5f135a2d69864f4d34a5896abd6e8b03ebdd44a537e84aaba96c"},"schema_version":"1.0"},"canonical_sha256":"c0b2a163f4fd9eda75336277b4f6b032889b6f8d165c4eb3b511f5fd93c48201","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:27:34.333468Z","signature_b64":"WMNYd95LLW1af0PwSquGIY5olbWLg35l0xXi3vINDDkOo+zTm9+K6b1NPZ7ISrwCH4zm9bjRL4OIWQ+KISGBCA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"c0b2a163f4fd9eda75336277b4f6b032889b6f8d165c4eb3b511f5fd93c48201","last_reissued_at":"2026-05-18T00:27:34.332806Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:27:34.332806Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1712.07515","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":"2026-05-18T00:27:34Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ZKAgyiPju0tApuTwtBKtXQeKGMqG8zGrWCYVo0mZ7MmWegJEY7aAcOKgcdMA1Pd3qftLthqB9sk4xOQ/KlSvDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T01:57:50.299374Z"},"content_sha256":"4a96e7cd8ab01b72674dc8e4bc77a7bac3789591dd3b626198c67ea6b08e1683","schema_version":"1.0","event_id":"sha256:4a96e7cd8ab01b72674dc8e4bc77a7bac3789591dd3b626198c67ea6b08e1683"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2017:YCZKCY7U7WPNU5JTMJ33J5VQGK","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"A Hubble diagram for quasars","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.CO"],"primary_cat":"astro-ph.GA","authors_text":"Elisabeta Lusso, Guido Risaliti, Susanna Bisogni","submitted_at":"2017-12-20T15:08:40Z","abstract_excerpt":"The cosmological model is at present not tested between the redshift of the farthest observed supernovae (z ~ 1.4) and that of the Cosmic Microwave Background (z ~ 1,100). Here we introduce a new method to measure the cosmological parameters: we show that quasars can be used as \"standard candles\" by employing the non-linear relation between their intrinsic UV and X-ray emission as an absolute distance indicator. We built a sample of ~ 1,900 quasars with available UV and X-ray observations, and produced a Hubble Diagram up to z ~ 5. The analysis of the quasar Hubble Diagram, when used in combin"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1712.07515","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":"2026-05-18T00:27:34Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"cDqS3j0wQTDQvt02kiojch3VN/YuURbcL13jXNi+zTRL6oglP7L3URtC5aXDJ0BtLGiIJ7jHFvu1aBAo44VdCg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T01:57:50.299963Z"},"content_sha256":"8332d63607093877584215cff9a9bb92cdc3c449afc0821d57a95be1359680a7","schema_version":"1.0","event_id":"sha256:8332d63607093877584215cff9a9bb92cdc3c449afc0821d57a95be1359680a7"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/YCZKCY7U7WPNU5JTMJ33J5VQGK/bundle.json","state_url":"https://pith.science/pith/YCZKCY7U7WPNU5JTMJ33J5VQGK/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/YCZKCY7U7WPNU5JTMJ33J5VQGK/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":"2026-05-31T01:57:50Z","links":{"resolver":"https://pith.science/pith/YCZKCY7U7WPNU5JTMJ33J5VQGK","bundle":"https://pith.science/pith/YCZKCY7U7WPNU5JTMJ33J5VQGK/bundle.json","state":"https://pith.science/pith/YCZKCY7U7WPNU5JTMJ33J5VQGK/state.json","well_known_bundle":"https://pith.science/.well-known/pith/YCZKCY7U7WPNU5JTMJ33J5VQGK/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2017:YCZKCY7U7WPNU5JTMJ33J5VQGK","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":"28aaf3bf74ee5f135a2d69864f4d34a5896abd6e8b03ebdd44a537e84aaba96c","cross_cats_sorted":["astro-ph.CO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-12-20T15:08:40Z","title_canon_sha256":"3eeb662443541ec24a73c3cd777c7d6516c14c62ad477d346b68323265ecbb12"},"schema_version":"1.0","source":{"id":"1712.07515","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1712.07515","created_at":"2026-05-18T00:27:34Z"},{"alias_kind":"arxiv_version","alias_value":"1712.07515v1","created_at":"2026-05-18T00:27:34Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1712.07515","created_at":"2026-05-18T00:27:34Z"},{"alias_kind":"pith_short_12","alias_value":"YCZKCY7U7WPN","created_at":"2026-05-18T12:31:56Z"},{"alias_kind":"pith_short_16","alias_value":"YCZKCY7U7WPNU5JT","created_at":"2026-05-18T12:31:56Z"},{"alias_kind":"pith_short_8","alias_value":"YCZKCY7U","created_at":"2026-05-18T12:31:56Z"}],"graph_snapshots":[{"event_id":"sha256:8332d63607093877584215cff9a9bb92cdc3c449afc0821d57a95be1359680a7","target":"graph","created_at":"2026-05-18T00:27:34Z","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 cosmological model is at present not tested between the redshift of the farthest observed supernovae (z ~ 1.4) and that of the Cosmic Microwave Background (z ~ 1,100). Here we introduce a new method to measure the cosmological parameters: we show that quasars can be used as \"standard candles\" by employing the non-linear relation between their intrinsic UV and X-ray emission as an absolute distance indicator. We built a sample of ~ 1,900 quasars with available UV and X-ray observations, and produced a Hubble Diagram up to z ~ 5. The analysis of the quasar Hubble Diagram, when used in combin","authors_text":"Elisabeta Lusso, Guido Risaliti, Susanna Bisogni","cross_cats":["astro-ph.CO"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-12-20T15:08:40Z","title":"A Hubble diagram for quasars"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1712.07515","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":"sha256:4a96e7cd8ab01b72674dc8e4bc77a7bac3789591dd3b626198c67ea6b08e1683","target":"record","created_at":"2026-05-18T00:27:34Z","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":"28aaf3bf74ee5f135a2d69864f4d34a5896abd6e8b03ebdd44a537e84aaba96c","cross_cats_sorted":["astro-ph.CO"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-12-20T15:08:40Z","title_canon_sha256":"3eeb662443541ec24a73c3cd777c7d6516c14c62ad477d346b68323265ecbb12"},"schema_version":"1.0","source":{"id":"1712.07515","kind":"arxiv","version":1}},"canonical_sha256":"c0b2a163f4fd9eda75336277b4f6b032889b6f8d165c4eb3b511f5fd93c48201","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"c0b2a163f4fd9eda75336277b4f6b032889b6f8d165c4eb3b511f5fd93c48201","first_computed_at":"2026-05-18T00:27:34.332806Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:27:34.332806Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"WMNYd95LLW1af0PwSquGIY5olbWLg35l0xXi3vINDDkOo+zTm9+K6b1NPZ7ISrwCH4zm9bjRL4OIWQ+KISGBCA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:27:34.333468Z","signed_message":"canonical_sha256_bytes"},"source_id":"1712.07515","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:4a96e7cd8ab01b72674dc8e4bc77a7bac3789591dd3b626198c67ea6b08e1683","sha256:8332d63607093877584215cff9a9bb92cdc3c449afc0821d57a95be1359680a7"],"state_sha256":"57886ec9a02d173a61778c90f3c1c5af1d1c0ec3352741b4799784430f3f48cb"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"P5Cu7gQIw4v4JD6BmpeICnJFtXF7PpXuCSmAaMi4I3iPaI4sykXDRpUlOH/shk9wrGGOafsepcJfLrE7AqiLCw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-31T01:57:50.303459Z","bundle_sha256":"e373246c6a68a1c0806e223291886f6259998318fb7ae6483d0651db121f2d99"}}