{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2005:YKLXGRX2RWNXXT6ZHKAIUL5NG7","short_pith_number":"pith:YKLXGRX2","schema_version":"1.0","canonical_sha256":"c2977346fa8d9b7bcfd93a808a2fad37cac913320c896aeef011b81a9d1befdd","source":{"kind":"arxiv","id":"astro-ph/0501521","version":2},"attestation_state":"computed","paper":{"title":"XMM-Newton Observations of High Redshift Quasars","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"B. Wilkes (Harvard-Smithsonian Center for Astrophysics), D. Grupe (The Ohio State University), P. Osmer (The Ohio State University), S. Mathur (The Ohio State University)","submitted_at":"2005-01-24T21:41:59Z","abstract_excerpt":"We report on our XMM observations of the high redshift quasars BR 2237--0607 (z=4.558) and BR 0351--1034 (z=4.351), together with 14 other z>4 objects found in the XMM public archive. Contrary to former reports, we do not find high redshift radio-loud quasars to be more absorbed than their radio-quiet counterparts. We find that the optical to X-ray spectral index alpha-ox is correlated with the luminosity density at 2500 A, but does not show a correlation with redshift. The mean 2-10 keV power-law slope of the 9 high redshift radio-quiet quasars in our sample for which a spectral analysis can "},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"astro-ph/0501521","kind":"arxiv","version":2},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"2005-01-24T21:41:59Z","cross_cats_sorted":[],"title_canon_sha256":"746fb3e70dd02f9a5ff4f23591c4843e4b573713860e2746b25e9a9cf689b57a","abstract_canon_sha256":"01e5625699ed0047ecdbe5c7ac9802c3e21b86c6678f15316f0190a45d70ca1d"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T04:36:30.250638Z","signature_b64":"GCOYxEQH3/aLVCXucfSlZP1p2qZHzAv+s55xFiKi/vXeHGwOwM42Fpvz4prH8K55lDwj1y8XiQxsylunKwLUBw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"c2977346fa8d9b7bcfd93a808a2fad37cac913320c896aeef011b81a9d1befdd","last_reissued_at":"2026-05-18T04:36:30.250248Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T04:36:30.250248Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"XMM-Newton Observations of High Redshift Quasars","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"B. Wilkes (Harvard-Smithsonian Center for Astrophysics), D. Grupe (The Ohio State University), P. Osmer (The Ohio State University), S. Mathur (The Ohio State University)","submitted_at":"2005-01-24T21:41:59Z","abstract_excerpt":"We report on our XMM observations of the high redshift quasars BR 2237--0607 (z=4.558) and BR 0351--1034 (z=4.351), together with 14 other z>4 objects found in the XMM public archive. Contrary to former reports, we do not find high redshift radio-loud quasars to be more absorbed than their radio-quiet counterparts. We find that the optical to X-ray spectral index alpha-ox is correlated with the luminosity density at 2500 A, but does not show a correlation with redshift. The mean 2-10 keV power-law slope of the 9 high redshift radio-quiet quasars in our sample for which a spectral analysis can "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0501521","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"},"aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/0501521","created_at":"2026-05-18T04:36:30.250301+00:00"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/0501521v2","created_at":"2026-05-18T04:36:30.250301+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/0501521","created_at":"2026-05-18T04:36:30.250301+00:00"},{"alias_kind":"pith_short_12","alias_value":"YKLXGRX2RWNX","created_at":"2026-05-18T12:25:53.939244+00:00"},{"alias_kind":"pith_short_16","alias_value":"YKLXGRX2RWNXXT6Z","created_at":"2026-05-18T12:25:53.939244+00:00"},{"alias_kind":"pith_short_8","alias_value":"YKLXGRX2","created_at":"2026-05-18T12:25:53.939244+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/YKLXGRX2RWNXXT6ZHKAIUL5NG7","json":"https://pith.science/pith/YKLXGRX2RWNXXT6ZHKAIUL5NG7.json","graph_json":"https://pith.science/api/pith-number/YKLXGRX2RWNXXT6ZHKAIUL5NG7/graph.json","events_json":"https://pith.science/api/pith-number/YKLXGRX2RWNXXT6ZHKAIUL5NG7/events.json","paper":"https://pith.science/paper/YKLXGRX2"},"agent_actions":{"view_html":"https://pith.science/pith/YKLXGRX2RWNXXT6ZHKAIUL5NG7","download_json":"https://pith.science/pith/YKLXGRX2RWNXXT6ZHKAIUL5NG7.json","view_paper":"https://pith.science/paper/YKLXGRX2","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=astro-ph/0501521&json=true","fetch_graph":"https://pith.science/api/pith-number/YKLXGRX2RWNXXT6ZHKAIUL5NG7/graph.json","fetch_events":"https://pith.science/api/pith-number/YKLXGRX2RWNXXT6ZHKAIUL5NG7/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/YKLXGRX2RWNXXT6ZHKAIUL5NG7/action/timestamp_anchor","attest_storage":"https://pith.science/pith/YKLXGRX2RWNXXT6ZHKAIUL5NG7/action/storage_attestation","attest_author":"https://pith.science/pith/YKLXGRX2RWNXXT6ZHKAIUL5NG7/action/author_attestation","sign_citation":"https://pith.science/pith/YKLXGRX2RWNXXT6ZHKAIUL5NG7/action/citation_signature","submit_replication":"https://pith.science/pith/YKLXGRX2RWNXXT6ZHKAIUL5NG7/action/replication_record"}},"created_at":"2026-05-18T04:36:30.250301+00:00","updated_at":"2026-05-18T04:36:30.250301+00:00"}