{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:3UH64K6ZTEX7SFOKA64QRNRGPH","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":"7c54bf171e642f184e67e8091841ee56f55ba244caf6a6920139f5c6e5cfb378","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-08-26T18:00:06Z","title_canon_sha256":"7a1190e4d769f6f61f10d4ed772fd68c5e9ca332fd3bc98de44d2e5f192e9730"},"schema_version":"1.0","source":{"id":"1908.09849","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1908.09849","created_at":"2026-07-05T00:09:03Z"},{"alias_kind":"arxiv_version","alias_value":"1908.09849v1","created_at":"2026-07-05T00:09:03Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1908.09849","created_at":"2026-07-05T00:09:03Z"},{"alias_kind":"pith_short_12","alias_value":"3UH64K6ZTEX7","created_at":"2026-07-05T00:09:03Z"},{"alias_kind":"pith_short_16","alias_value":"3UH64K6ZTEX7SFOK","created_at":"2026-07-05T00:09:03Z"},{"alias_kind":"pith_short_8","alias_value":"3UH64K6Z","created_at":"2026-07-05T00:09:03Z"}],"graph_snapshots":[{"event_id":"sha256:3ea732de87beea7907c47091fd88d21c13a5a83ce89a79c938b91ea09ad7c874","target":"graph","created_at":"2026-07-05T00:09:03Z","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"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/1908.09849/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"X-ray emission from QSOs has been used to assess SMBH accretion properties up to $z$~6. However, at $z>6$ only ~15 QSOs are covered by sensitive X-ray observations, preventing a statistically significant investigation of the X-ray properties of QSOs in the first Gyr of the Universe. We present new Chandra observations of 10 $z>6$ QSOs, selected to have virial black-hole mass estimates from Mg II line spectroscopy. Adding archival X-ray data for an additional 15 $z>6$ QSOs, we investigate the X-ray properties of the QSO population in the first Gyr of the Universe, focusing in particular on the ","authors_text":"Andrea Comastri, Bin Luo, Cristian Vignali, Fabio Vito, Francesca Civano, Francesco Calura, Franz Erik Bauer, Gianni Zamorani, Marcella Brusa, Ohad Shemmer, Riccardo Nanni, Roberto Gilli, William Nielsen Brandt","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-08-26T18:00:06Z","title":"The X-ray properties of $z>6$ quasars: no evident evolution of accretion physics in the first Gyr of the Universe"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1908.09849","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":"sha256:357509b40f256a3af27ec4a6d789210509555a76a4947a130aba9ee9a00fd22d","target":"record","created_at":"2026-07-05T00:09:03Z","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":"7c54bf171e642f184e67e8091841ee56f55ba244caf6a6920139f5c6e5cfb378","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-08-26T18:00:06Z","title_canon_sha256":"7a1190e4d769f6f61f10d4ed772fd68c5e9ca332fd3bc98de44d2e5f192e9730"},"schema_version":"1.0","source":{"id":"1908.09849","kind":"arxiv","version":1}},"canonical_sha256":"dd0fee2bd9992ff915ca07b908b62679d0e4721410e56977666bf29f040186d0","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"dd0fee2bd9992ff915ca07b908b62679d0e4721410e56977666bf29f040186d0","first_computed_at":"2026-07-05T00:09:03.777340Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T00:09:03.777340Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"xWY37X3g3NUwm9guVFN9i5seXqGF3cYFCfEE9zCMD2goBPLyAFI6MeIlspRjtAQ9wl/xYRa91NpVuqD5pBtbAw==","signature_status":"signed_v1","signed_at":"2026-07-05T00:09:03.777726Z","signed_message":"canonical_sha256_bytes"},"source_id":"1908.09849","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:357509b40f256a3af27ec4a6d789210509555a76a4947a130aba9ee9a00fd22d","sha256:3ea732de87beea7907c47091fd88d21c13a5a83ce89a79c938b91ea09ad7c874"],"state_sha256":"4a14d95522f74cf6d541349dc81eff3567d549d1ebf40993332be223d0e19321"}