{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2023:VKPKBBRJDSJBLTBW53OZZVRIEY","short_pith_number":"pith:VKPKBBRJ","canonical_record":{"source":{"id":"2301.04002","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2023-01-10T14:49:52Z","cross_cats_sorted":[],"title_canon_sha256":"cdd199c062aa9b124e3db247564ec210ac66fdafe649a90218d11447dbbb6b47","abstract_canon_sha256":"702d7c0f6260934bb04e6a02a0f9f224e321b7aecfb99e5262f47886ab854571"},"schema_version":"1.0"},"canonical_sha256":"aa9ea086291c9215cc36eedd9cd628261b0cdbc18d69cf169c85d238a99a8c18","source":{"kind":"arxiv","id":"2301.04002","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2301.04002","created_at":"2026-07-05T05:32:13Z"},{"alias_kind":"arxiv_version","alias_value":"2301.04002v2","created_at":"2026-07-05T05:32:13Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2301.04002","created_at":"2026-07-05T05:32:13Z"},{"alias_kind":"pith_short_12","alias_value":"VKPKBBRJDSJB","created_at":"2026-07-05T05:32:13Z"},{"alias_kind":"pith_short_16","alias_value":"VKPKBBRJDSJBLTBW","created_at":"2026-07-05T05:32:13Z"},{"alias_kind":"pith_short_8","alias_value":"VKPKBBRJ","created_at":"2026-07-05T05:32:13Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2023:VKPKBBRJDSJBLTBW53OZZVRIEY","target":"record","payload":{"canonical_record":{"source":{"id":"2301.04002","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2023-01-10T14:49:52Z","cross_cats_sorted":[],"title_canon_sha256":"cdd199c062aa9b124e3db247564ec210ac66fdafe649a90218d11447dbbb6b47","abstract_canon_sha256":"702d7c0f6260934bb04e6a02a0f9f224e321b7aecfb99e5262f47886ab854571"},"schema_version":"1.0"},"canonical_sha256":"aa9ea086291c9215cc36eedd9cd628261b0cdbc18d69cf169c85d238a99a8c18","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T05:32:13.078485Z","signature_b64":"kMLoocA0KsyRe5NzFC+JYrpYnXv2M+u7e3r2jc+r42DZA1e7MFXvujmvc+17kQDXcBbxkJtDWyVrUb0Dj/zABw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"aa9ea086291c9215cc36eedd9cd628261b0cdbc18d69cf169c85d238a99a8c18","last_reissued_at":"2026-07-05T05:32:13.078075Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T05:32:13.078075Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2301.04002","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-05T05:32:13Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"EAluG5wWx+YdE2rh1iUDrxw/Cax5RvS/Ohn81mv3H3X6rPSaUqMYJXe0maS26UCSult13S75o+XIKpr9c4jPAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-07T04:03:54.885483Z"},"content_sha256":"5e788307ae13eeb992d8d6d6b68e2e1d498f6020ae04e64e88b21e9fecce7c79","schema_version":"1.0","event_id":"sha256:5e788307ae13eeb992d8d6d6b68e2e1d498f6020ae04e64e88b21e9fecce7c79"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2023:VKPKBBRJDSJBLTBW53OZZVRIEY","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"X-ray Polarimetry as a Tool to Measure the Black Hole Spin in Microquasars: Simulations of IXPE Capabilities","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.HE","authors_text":"Giorgio Matt, Jiri Svoboda, Michal Bursa, Michal Dovciak, Niccolo Di Lalla, Roberto Taverna, Romana Mikusincova, Wenda Zhang","submitted_at":"2023-01-10T14:49:52Z","abstract_excerpt":"Measurements of the angular momentum (spin) of astrophysical black holes are extremely important, as they provide information on the black hole formation and evolution. We present simulated observations of a X-ray binary system with the Imaging X-ray Polarimetry Explorer (IXPE), with the aim to study the robustness of black hole spin and geometry measurements using X-ray polarimetry. As a representative example, we used the parameters of GRS 1915+105 in its former unobscured, soft state. In order to simulate the polarization properties, we modeled the source emission with a multicolor blackbod"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2301.04002","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2301.04002/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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":"2026-07-05T05:32:13Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"R07U/4q4Zc+Zu3UQ/tEYeD2lwqr28CLR7Lcye2PlAvGYQQ1U3Kv9nEHjqWDLwYOvIsYg0UTvRsd/ELThLPQcDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-07T04:03:54.886395Z"},"content_sha256":"d0fdf9e3b6b38a04c18ba145eaf7f8e705c2d2817f20770f734f55b9a1f77f6a","schema_version":"1.0","event_id":"sha256:d0fdf9e3b6b38a04c18ba145eaf7f8e705c2d2817f20770f734f55b9a1f77f6a"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/VKPKBBRJDSJBLTBW53OZZVRIEY/bundle.json","state_url":"https://pith.science/pith/VKPKBBRJDSJBLTBW53OZZVRIEY/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/VKPKBBRJDSJBLTBW53OZZVRIEY/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":"2026-08-07T04:03:54Z","links":{"resolver":"https://pith.science/pith/VKPKBBRJDSJBLTBW53OZZVRIEY","bundle":"https://pith.science/pith/VKPKBBRJDSJBLTBW53OZZVRIEY/bundle.json","state":"https://pith.science/pith/VKPKBBRJDSJBLTBW53OZZVRIEY/state.json","well_known_bundle":"https://pith.science/.well-known/pith/VKPKBBRJDSJBLTBW53OZZVRIEY/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2023:VKPKBBRJDSJBLTBW53OZZVRIEY","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":"702d7c0f6260934bb04e6a02a0f9f224e321b7aecfb99e5262f47886ab854571","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2023-01-10T14:49:52Z","title_canon_sha256":"cdd199c062aa9b124e3db247564ec210ac66fdafe649a90218d11447dbbb6b47"},"schema_version":"1.0","source":{"id":"2301.04002","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2301.04002","created_at":"2026-07-05T05:32:13Z"},{"alias_kind":"arxiv_version","alias_value":"2301.04002v2","created_at":"2026-07-05T05:32:13Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2301.04002","created_at":"2026-07-05T05:32:13Z"},{"alias_kind":"pith_short_12","alias_value":"VKPKBBRJDSJB","created_at":"2026-07-05T05:32:13Z"},{"alias_kind":"pith_short_16","alias_value":"VKPKBBRJDSJBLTBW","created_at":"2026-07-05T05:32:13Z"},{"alias_kind":"pith_short_8","alias_value":"VKPKBBRJ","created_at":"2026-07-05T05:32:13Z"}],"graph_snapshots":[{"event_id":"sha256:d0fdf9e3b6b38a04c18ba145eaf7f8e705c2d2817f20770f734f55b9a1f77f6a","target":"graph","created_at":"2026-07-05T05:32:13Z","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"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2301.04002/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Measurements of the angular momentum (spin) of astrophysical black holes are extremely important, as they provide information on the black hole formation and evolution. We present simulated observations of a X-ray binary system with the Imaging X-ray Polarimetry Explorer (IXPE), with the aim to study the robustness of black hole spin and geometry measurements using X-ray polarimetry. As a representative example, we used the parameters of GRS 1915+105 in its former unobscured, soft state. In order to simulate the polarization properties, we modeled the source emission with a multicolor blackbod","authors_text":"Giorgio Matt, Jiri Svoboda, Michal Bursa, Michal Dovciak, Niccolo Di Lalla, Roberto Taverna, Romana Mikusincova, Wenda Zhang","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2023-01-10T14:49:52Z","title":"X-ray Polarimetry as a Tool to Measure the Black Hole Spin in Microquasars: Simulations of IXPE Capabilities"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2301.04002","kind":"arxiv","version":2},"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":"sha256:5e788307ae13eeb992d8d6d6b68e2e1d498f6020ae04e64e88b21e9fecce7c79","target":"record","created_at":"2026-07-05T05:32:13Z","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":"702d7c0f6260934bb04e6a02a0f9f224e321b7aecfb99e5262f47886ab854571","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2023-01-10T14:49:52Z","title_canon_sha256":"cdd199c062aa9b124e3db247564ec210ac66fdafe649a90218d11447dbbb6b47"},"schema_version":"1.0","source":{"id":"2301.04002","kind":"arxiv","version":2}},"canonical_sha256":"aa9ea086291c9215cc36eedd9cd628261b0cdbc18d69cf169c85d238a99a8c18","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"aa9ea086291c9215cc36eedd9cd628261b0cdbc18d69cf169c85d238a99a8c18","first_computed_at":"2026-07-05T05:32:13.078075Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T05:32:13.078075Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"kMLoocA0KsyRe5NzFC+JYrpYnXv2M+u7e3r2jc+r42DZA1e7MFXvujmvc+17kQDXcBbxkJtDWyVrUb0Dj/zABw==","signature_status":"signed_v1","signed_at":"2026-07-05T05:32:13.078485Z","signed_message":"canonical_sha256_bytes"},"source_id":"2301.04002","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:5e788307ae13eeb992d8d6d6b68e2e1d498f6020ae04e64e88b21e9fecce7c79","sha256:d0fdf9e3b6b38a04c18ba145eaf7f8e705c2d2817f20770f734f55b9a1f77f6a"],"state_sha256":"b77ea8ff25dbb1ea9a825371f72f93042737870520c79f7a21b094e49f3e355f"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"vk0e53/GbxqSU1C6mFQR4wYqYDZ1fYBfmVxSlUAlBiNUrnRa4aBbIiioa6o3wbm8cfojw8UqB3eFvmIS+0caCA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-07T04:03:54.892761Z","bundle_sha256":"fe7bf714fa1cd566683687faf9beb10d5b66a19a5ae9edb7b3a8e6d9b057767d"}}