{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2012:HUHVNFY64Z5CYC5DFMDGEVUCJY","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":"3e6a0cad1b35ce70001c5a51afada56aed49c56a07be09fa5877ccff50f79faa","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-04-13T05:03:11Z","title_canon_sha256":"4251da80570b1a2d7fe00f1cc23ce66a78935059cc9098f2feaeabcaff8c60b2"},"schema_version":"1.0","source":{"id":"1204.2881","kind":"arxiv","version":4}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1204.2881","created_at":"2026-05-18T01:57:52Z"},{"alias_kind":"arxiv_version","alias_value":"1204.2881v4","created_at":"2026-05-18T01:57:52Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1204.2881","created_at":"2026-05-18T01:57:52Z"},{"alias_kind":"pith_short_12","alias_value":"HUHVNFY64Z5C","created_at":"2026-05-18T12:27:09Z"},{"alias_kind":"pith_short_16","alias_value":"HUHVNFY64Z5CYC5D","created_at":"2026-05-18T12:27:09Z"},{"alias_kind":"pith_short_8","alias_value":"HUHVNFY6","created_at":"2026-05-18T12:27:09Z"}],"graph_snapshots":[{"event_id":"sha256:4d0aec658fa609ecde85b0be216f3608a30820e485a464511376d21d985c560a","target":"graph","created_at":"2026-05-18T01:57:52Z","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":"From the first published z > 3 survey of 21-cm absorption within the hosts of radio galaxies and quasars, we found an apparent dearth of cool neutral gas at high redshift. From a detailed analysis of the photometry, each object is found to have a 1216 A continuum luminosity in excess of L ~1e23 W/Hz, a critical value above which 21-cm has never been detected at any redshift. At these wavelengths, and below, hydrogen is excited above the ground state so that it cannot absorb in 21-cm. In order to apply the equation of photoionsation equilibrium, we demonstrate that this critical value also appl","authors_text":"M. T. Whiting, S. J. Curran","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-04-13T05:03:11Z","title":"Complete ionisation of the neutral gas: why there are so few detections of 21-cm hydrogen in high redshift radio galaxies and quasars"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1204.2881","kind":"arxiv","version":4},"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":"sha256:04283a79da2a77633eede0e4e8bbfc601f73b8930f735d0ca1d2e55558f2b8b5","target":"record","created_at":"2026-05-18T01:57:52Z","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":"3e6a0cad1b35ce70001c5a51afada56aed49c56a07be09fa5877ccff50f79faa","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-04-13T05:03:11Z","title_canon_sha256":"4251da80570b1a2d7fe00f1cc23ce66a78935059cc9098f2feaeabcaff8c60b2"},"schema_version":"1.0","source":{"id":"1204.2881","kind":"arxiv","version":4}},"canonical_sha256":"3d0f56971ee67a2c0ba32b066256824e204700fa28aba354ae9685eca317b36a","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"3d0f56971ee67a2c0ba32b066256824e204700fa28aba354ae9685eca317b36a","first_computed_at":"2026-05-18T01:57:52.879423Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:57:52.879423Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"xIRGiNh5XCU7Y5xpDiZDgehxOEw+pJwzgFIPbHENB+n2YdvkAAPBKnqfGV7PocogsYFGaadiIM8C7hf6nXLABg==","signature_status":"signed_v1","signed_at":"2026-05-18T01:57:52.879989Z","signed_message":"canonical_sha256_bytes"},"source_id":"1204.2881","source_kind":"arxiv","source_version":4}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:04283a79da2a77633eede0e4e8bbfc601f73b8930f735d0ca1d2e55558f2b8b5","sha256:4d0aec658fa609ecde85b0be216f3608a30820e485a464511376d21d985c560a"],"state_sha256":"5b26fdc8d2608d2debd0d5b225aa8748364c3f38b224511059b19efb94ec5341"}