{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2015:2TC2TSS5V36JBULL3IEP45YSUF","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":"2c9853b44d67f57782d31de145aeaeebec651b6b57ebb0fdca8ebe8396defadf","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2015-09-09T20:13:56Z","title_canon_sha256":"efb0f491606bd3ad8feccd36ecf13b92303f39d79276c3b6d95cdc0071d660b6"},"schema_version":"1.0","source":{"id":"1509.02920","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1509.02920","created_at":"2026-05-18T01:32:26Z"},{"alias_kind":"arxiv_version","alias_value":"1509.02920v1","created_at":"2026-05-18T01:32:26Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1509.02920","created_at":"2026-05-18T01:32:26Z"},{"alias_kind":"pith_short_12","alias_value":"2TC2TSS5V36J","created_at":"2026-05-18T12:29:02Z"},{"alias_kind":"pith_short_16","alias_value":"2TC2TSS5V36JBULL","created_at":"2026-05-18T12:29:02Z"},{"alias_kind":"pith_short_8","alias_value":"2TC2TSS5","created_at":"2026-05-18T12:29:02Z"}],"graph_snapshots":[{"event_id":"sha256:9e0c25762818d6a63852a6537abb5a6503af58af7dc50ce2e463259dd2f2ced2","target":"graph","created_at":"2026-05-18T01:32:26Z","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":"Mergers of gas-rich galaxies are key events in the hierarchical built-up of cosmic structures, and can lead to the formation of massive black hole binaries. By means of high-resolution hydrodynamical simulations we consider the late stages of a gas-rich major merger, detailing the dynamics of two circumnuclear discs, and of the hosted massive black holes during their pairing phase. During the merger gas clumps with masses of a fraction of the black hole mass form because of fragmentation. Such high-density gas is very effective in forming stars, and the most massive clumps can substantially pe","authors_text":"Alessandro Lupi, Francesco Haardt, Massimo Dotti, Monica Colpi","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2015-09-09T20:13:56Z","title":"Massive black hole and gas dynamics in mergers of galaxy nuclei - II. Black hole sinking in star-forming nuclear discs"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1509.02920","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":"sha256:7d2ea480dd233b4588054556210fab833a41528738781ee5b4b3854a4e65d727","target":"record","created_at":"2026-05-18T01:32:26Z","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":"2c9853b44d67f57782d31de145aeaeebec651b6b57ebb0fdca8ebe8396defadf","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2015-09-09T20:13:56Z","title_canon_sha256":"efb0f491606bd3ad8feccd36ecf13b92303f39d79276c3b6d95cdc0071d660b6"},"schema_version":"1.0","source":{"id":"1509.02920","kind":"arxiv","version":1}},"canonical_sha256":"d4c5a9ca5daefc90d16bda08fe7712a16c5e53a6bc489d2268e54ec8b30e843f","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"d4c5a9ca5daefc90d16bda08fe7712a16c5e53a6bc489d2268e54ec8b30e843f","first_computed_at":"2026-05-18T01:32:26.550460Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:32:26.550460Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"uyfKYbVRE+ROkXM4TOPQEMdI2//IU5UMpOLzb/Hqg+S73tUqtufkqnHjVZx/xgToPnxJ3qIRj15im1ERqz06BQ==","signature_status":"signed_v1","signed_at":"2026-05-18T01:32:26.551137Z","signed_message":"canonical_sha256_bytes"},"source_id":"1509.02920","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:7d2ea480dd233b4588054556210fab833a41528738781ee5b4b3854a4e65d727","sha256:9e0c25762818d6a63852a6537abb5a6503af58af7dc50ce2e463259dd2f2ced2"],"state_sha256":"22b3f805d8da807c84ce9e81dd65bf129e3a5a26a8d13bff5c81e277a5346136"}