{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2017:FQY2WPHEA64S4AZGR46PH6ZT3W","short_pith_number":"pith:FQY2WPHE","canonical_record":{"source":{"id":"1701.02685","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-01-10T16:55:02Z","cross_cats_sorted":[],"title_canon_sha256":"1f145dabb48fd2abd970bd61ef8dedcfe1b1bbac55aaa389a354e169330a4cf9","abstract_canon_sha256":"9a0e4fad733ba2c740bbe06522514db4449d50d56fb2a67d4f884db316cc80e3"},"schema_version":"1.0"},"canonical_sha256":"2c31ab3ce407b92e03268f3cf3fb33ddbfa720696b5303fd36276155f3d8a3f9","source":{"kind":"arxiv","id":"1701.02685","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1701.02685","created_at":"2026-05-18T00:48:15Z"},{"alias_kind":"arxiv_version","alias_value":"1701.02685v1","created_at":"2026-05-18T00:48:15Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1701.02685","created_at":"2026-05-18T00:48:15Z"},{"alias_kind":"pith_short_12","alias_value":"FQY2WPHEA64S","created_at":"2026-05-18T12:31:15Z"},{"alias_kind":"pith_short_16","alias_value":"FQY2WPHEA64S4AZG","created_at":"2026-05-18T12:31:15Z"},{"alias_kind":"pith_short_8","alias_value":"FQY2WPHE","created_at":"2026-05-18T12:31:15Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2017:FQY2WPHEA64S4AZGR46PH6ZT3W","target":"record","payload":{"canonical_record":{"source":{"id":"1701.02685","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-01-10T16:55:02Z","cross_cats_sorted":[],"title_canon_sha256":"1f145dabb48fd2abd970bd61ef8dedcfe1b1bbac55aaa389a354e169330a4cf9","abstract_canon_sha256":"9a0e4fad733ba2c740bbe06522514db4449d50d56fb2a67d4f884db316cc80e3"},"schema_version":"1.0"},"canonical_sha256":"2c31ab3ce407b92e03268f3cf3fb33ddbfa720696b5303fd36276155f3d8a3f9","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:48:15.413730Z","signature_b64":"A0Ym+GhSTm3aBQUSaJwsK2y0/B+3mJpWwaEga9qKqve3KDZZlwRymwamRGUWSbgcu7cXObXUupjJXc8EGtuMDw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"2c31ab3ce407b92e03268f3cf3fb33ddbfa720696b5303fd36276155f3d8a3f9","last_reissued_at":"2026-05-18T00:48:15.413011Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:48:15.413011Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1701.02685","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T00:48:15Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"bLMcdotvnLM1D2p+iFBPkxLaPDQtPSb0UhC8xo6sp+Ut87vsXMifwgZP5lIX57zlyg6T3KRP3LvSpSuynAH+AA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-08T18:08:43.091993Z"},"content_sha256":"a588ec43ec52e3412764c68a19168d756e47e010fdc61da891b7e3821ac37a46","schema_version":"1.0","event_id":"sha256:a588ec43ec52e3412764c68a19168d756e47e010fdc61da891b7e3821ac37a46"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2017:FQY2WPHEA64S4AZGR46PH6ZT3W","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Forming disc galaxies in major mergers II. The central mass concentration problem and a comparison of GADGET3 with GIZMO","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"E. Athanassoula, N. Peschken, S.A. Rodionov","submitted_at":"2017-01-10T16:55:02Z","abstract_excerpt":"Context: In a series of papers, we study the major merger of two disk galaxies in order to establish whether or not such a merger can produce a disc galaxy. Aims: Our aim here is to describe in detail the technical aspects of our numerical experiments. Methods: We discuss the initial conditions of our major merger, which consist of two protogalaxies on a collision orbit. We show that such merger simulations can produce a non-realistic central mass concentration, and we propose simple, parametric, AGN-like feedback as a solution to this problem. Our AGN-like feedback algorithm is very simple: a"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1701.02685","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"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T00:48:15Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"H0dtpAGZCNEXSmcr9p0eFO+lZyyiEE8GIFYraBO1GZOXzBYUyzTWpwV3vorVWgXhErQ87U91zoEWmREpK8+lCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-08T18:08:43.092701Z"},"content_sha256":"ff041d51911312b8e0de3be0cb6cef9f45c8b5e9bdd5ef0e016c02701d20f51d","schema_version":"1.0","event_id":"sha256:ff041d51911312b8e0de3be0cb6cef9f45c8b5e9bdd5ef0e016c02701d20f51d"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/FQY2WPHEA64S4AZGR46PH6ZT3W/bundle.json","state_url":"https://pith.science/pith/FQY2WPHEA64S4AZGR46PH6ZT3W/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/FQY2WPHEA64S4AZGR46PH6ZT3W/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-06-08T18:08:43Z","links":{"resolver":"https://pith.science/pith/FQY2WPHEA64S4AZGR46PH6ZT3W","bundle":"https://pith.science/pith/FQY2WPHEA64S4AZGR46PH6ZT3W/bundle.json","state":"https://pith.science/pith/FQY2WPHEA64S4AZGR46PH6ZT3W/state.json","well_known_bundle":"https://pith.science/.well-known/pith/FQY2WPHEA64S4AZGR46PH6ZT3W/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2017:FQY2WPHEA64S4AZGR46PH6ZT3W","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":"9a0e4fad733ba2c740bbe06522514db4449d50d56fb2a67d4f884db316cc80e3","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-01-10T16:55:02Z","title_canon_sha256":"1f145dabb48fd2abd970bd61ef8dedcfe1b1bbac55aaa389a354e169330a4cf9"},"schema_version":"1.0","source":{"id":"1701.02685","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1701.02685","created_at":"2026-05-18T00:48:15Z"},{"alias_kind":"arxiv_version","alias_value":"1701.02685v1","created_at":"2026-05-18T00:48:15Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1701.02685","created_at":"2026-05-18T00:48:15Z"},{"alias_kind":"pith_short_12","alias_value":"FQY2WPHEA64S","created_at":"2026-05-18T12:31:15Z"},{"alias_kind":"pith_short_16","alias_value":"FQY2WPHEA64S4AZG","created_at":"2026-05-18T12:31:15Z"},{"alias_kind":"pith_short_8","alias_value":"FQY2WPHE","created_at":"2026-05-18T12:31:15Z"}],"graph_snapshots":[{"event_id":"sha256:ff041d51911312b8e0de3be0cb6cef9f45c8b5e9bdd5ef0e016c02701d20f51d","target":"graph","created_at":"2026-05-18T00:48:15Z","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":"Context: In a series of papers, we study the major merger of two disk galaxies in order to establish whether or not such a merger can produce a disc galaxy. Aims: Our aim here is to describe in detail the technical aspects of our numerical experiments. Methods: We discuss the initial conditions of our major merger, which consist of two protogalaxies on a collision orbit. We show that such merger simulations can produce a non-realistic central mass concentration, and we propose simple, parametric, AGN-like feedback as a solution to this problem. Our AGN-like feedback algorithm is very simple: a","authors_text":"E. Athanassoula, N. Peschken, S.A. Rodionov","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-01-10T16:55:02Z","title":"Forming disc galaxies in major mergers II. The central mass concentration problem and a comparison of GADGET3 with GIZMO"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1701.02685","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:a588ec43ec52e3412764c68a19168d756e47e010fdc61da891b7e3821ac37a46","target":"record","created_at":"2026-05-18T00:48:15Z","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":"9a0e4fad733ba2c740bbe06522514db4449d50d56fb2a67d4f884db316cc80e3","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-01-10T16:55:02Z","title_canon_sha256":"1f145dabb48fd2abd970bd61ef8dedcfe1b1bbac55aaa389a354e169330a4cf9"},"schema_version":"1.0","source":{"id":"1701.02685","kind":"arxiv","version":1}},"canonical_sha256":"2c31ab3ce407b92e03268f3cf3fb33ddbfa720696b5303fd36276155f3d8a3f9","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"2c31ab3ce407b92e03268f3cf3fb33ddbfa720696b5303fd36276155f3d8a3f9","first_computed_at":"2026-05-18T00:48:15.413011Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:48:15.413011Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"A0Ym+GhSTm3aBQUSaJwsK2y0/B+3mJpWwaEga9qKqve3KDZZlwRymwamRGUWSbgcu7cXObXUupjJXc8EGtuMDw==","signature_status":"signed_v1","signed_at":"2026-05-18T00:48:15.413730Z","signed_message":"canonical_sha256_bytes"},"source_id":"1701.02685","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:a588ec43ec52e3412764c68a19168d756e47e010fdc61da891b7e3821ac37a46","sha256:ff041d51911312b8e0de3be0cb6cef9f45c8b5e9bdd5ef0e016c02701d20f51d"],"state_sha256":"2e1c172a004eaf187a12c86c196809508174818ce3bcc123ef981247dc238b79"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"c5v8s8A2jVKKZgX9OKIKK5ewJgAOSh+rP0i0FbjnTy6o4HRyLVVXxz4p5b3I3N5fiEyNr2GfGt0pD0LgZfkKCg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-08T18:08:43.096529Z","bundle_sha256":"632ba472c9fdb7db81d027bd0ad954880d19f710c6a1f7ee979f4773775735e0"}}