{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2010:Q2PKUMFJT7NFTSJGG3453MSEAO","short_pith_number":"pith:Q2PKUMFJ","schema_version":"1.0","canonical_sha256":"869eaa30a99fda59c92636f9ddb244038abda4d2761ed84ec01f39ed8ab0a080","source":{"kind":"arxiv","id":"1008.2065","version":1},"attestation_state":"computed","paper":{"title":"Detection of Strong Short-Term Variability in NGC 6946 X-1","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.HE","authors_text":"Fengyun Rao (Tsinghua), Hua Feng (Tsinghua), Philip Kaaret (Iowa)","submitted_at":"2010-08-12T08:35:37Z","abstract_excerpt":"Using two archival XMM-Newton observations, we identify strong X-ray flux variations in NGC 6946 X-1 indicating it is the most variable ultraluminous X-ray source (ULX) on mHz time scales known so far. The 1-10 keV lightcurve exhibits variability with a fractional rms amplitude of 60% integrated in the frequency range of 1-100 mHz. The power spectral density of the source shows a flat-topped spectrum that breaks at about 3 mHz with possible quasi-periodic oscillations (QPOs) near 8.5 mHz. Black hole binaries usually produce strong fast variability in the hard or intermediate state. The energy "},"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":"1008.2065","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2010-08-12T08:35:37Z","cross_cats_sorted":[],"title_canon_sha256":"52298112389d559df62970c4b3cd8d5f0f89fb803f03e782e3b63e83dccd69d8","abstract_canon_sha256":"e418a62d799749ce05eee68e58c5e880491cc4edb592d0fde9754bdf8c7a7ba6"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:05:49.113325Z","signature_b64":"CluoNAolhWyavJq5pw3m73Fz9BmdouCoKS1dz47dHjxeN79zQHpv86zzQ43lyp3R2CMVVWnyzyyojCi5g8r9Bw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"869eaa30a99fda59c92636f9ddb244038abda4d2761ed84ec01f39ed8ab0a080","last_reissued_at":"2026-05-18T02:05:49.112668Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:05:49.112668Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Detection of Strong Short-Term Variability in NGC 6946 X-1","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.HE","authors_text":"Fengyun Rao (Tsinghua), Hua Feng (Tsinghua), Philip Kaaret (Iowa)","submitted_at":"2010-08-12T08:35:37Z","abstract_excerpt":"Using two archival XMM-Newton observations, we identify strong X-ray flux variations in NGC 6946 X-1 indicating it is the most variable ultraluminous X-ray source (ULX) on mHz time scales known so far. The 1-10 keV lightcurve exhibits variability with a fractional rms amplitude of 60% integrated in the frequency range of 1-100 mHz. The power spectral density of the source shows a flat-topped spectrum that breaks at about 3 mHz with possible quasi-periodic oscillations (QPOs) near 8.5 mHz. Black hole binaries usually produce strong fast variability in the hard or intermediate state. The energy "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1008.2065","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"},"aliases":[{"alias_kind":"arxiv","alias_value":"1008.2065","created_at":"2026-05-18T02:05:49.112761+00:00"},{"alias_kind":"arxiv_version","alias_value":"1008.2065v1","created_at":"2026-05-18T02:05:49.112761+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1008.2065","created_at":"2026-05-18T02:05:49.112761+00:00"},{"alias_kind":"pith_short_12","alias_value":"Q2PKUMFJT7NF","created_at":"2026-05-18T12:26:12.377268+00:00"},{"alias_kind":"pith_short_16","alias_value":"Q2PKUMFJT7NFTSJG","created_at":"2026-05-18T12:26:12.377268+00:00"},{"alias_kind":"pith_short_8","alias_value":"Q2PKUMFJ","created_at":"2026-05-18T12:26:12.377268+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/Q2PKUMFJT7NFTSJGG3453MSEAO","json":"https://pith.science/pith/Q2PKUMFJT7NFTSJGG3453MSEAO.json","graph_json":"https://pith.science/api/pith-number/Q2PKUMFJT7NFTSJGG3453MSEAO/graph.json","events_json":"https://pith.science/api/pith-number/Q2PKUMFJT7NFTSJGG3453MSEAO/events.json","paper":"https://pith.science/paper/Q2PKUMFJ"},"agent_actions":{"view_html":"https://pith.science/pith/Q2PKUMFJT7NFTSJGG3453MSEAO","download_json":"https://pith.science/pith/Q2PKUMFJT7NFTSJGG3453MSEAO.json","view_paper":"https://pith.science/paper/Q2PKUMFJ","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=1008.2065&json=true","fetch_graph":"https://pith.science/api/pith-number/Q2PKUMFJT7NFTSJGG3453MSEAO/graph.json","fetch_events":"https://pith.science/api/pith-number/Q2PKUMFJT7NFTSJGG3453MSEAO/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/Q2PKUMFJT7NFTSJGG3453MSEAO/action/timestamp_anchor","attest_storage":"https://pith.science/pith/Q2PKUMFJT7NFTSJGG3453MSEAO/action/storage_attestation","attest_author":"https://pith.science/pith/Q2PKUMFJT7NFTSJGG3453MSEAO/action/author_attestation","sign_citation":"https://pith.science/pith/Q2PKUMFJT7NFTSJGG3453MSEAO/action/citation_signature","submit_replication":"https://pith.science/pith/Q2PKUMFJT7NFTSJGG3453MSEAO/action/replication_record"}},"created_at":"2026-05-18T02:05:49.112761+00:00","updated_at":"2026-05-18T02:05:49.112761+00:00"}