{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:A4XU6T3XORZXSY7MPG3YHD6SMR","short_pith_number":"pith:A4XU6T3X","canonical_record":{"source":{"id":"1802.06252","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-02-17T15:44:04Z","cross_cats_sorted":[],"title_canon_sha256":"353fc6066381c2aef11a71b8d2e43ff7f34e37618aa8788c5a206374cf0e9f62","abstract_canon_sha256":"323b8d4dbcbe912b4b0a7b9c65dad62624d13b1d85fb3ea4790336fbdceb0de1"},"schema_version":"1.0"},"canonical_sha256":"072f4f4f7774737963ec79b7838fd2646ba6b7c2b7ba78800879d922c0c16463","source":{"kind":"arxiv","id":"1802.06252","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1802.06252","created_at":"2026-05-18T00:00:45Z"},{"alias_kind":"arxiv_version","alias_value":"1802.06252v2","created_at":"2026-05-18T00:00:45Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1802.06252","created_at":"2026-05-18T00:00:45Z"},{"alias_kind":"pith_short_12","alias_value":"A4XU6T3XORZX","created_at":"2026-05-18T12:32:13Z"},{"alias_kind":"pith_short_16","alias_value":"A4XU6T3XORZXSY7M","created_at":"2026-05-18T12:32:13Z"},{"alias_kind":"pith_short_8","alias_value":"A4XU6T3X","created_at":"2026-05-18T12:32:13Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:A4XU6T3XORZXSY7MPG3YHD6SMR","target":"record","payload":{"canonical_record":{"source":{"id":"1802.06252","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-02-17T15:44:04Z","cross_cats_sorted":[],"title_canon_sha256":"353fc6066381c2aef11a71b8d2e43ff7f34e37618aa8788c5a206374cf0e9f62","abstract_canon_sha256":"323b8d4dbcbe912b4b0a7b9c65dad62624d13b1d85fb3ea4790336fbdceb0de1"},"schema_version":"1.0"},"canonical_sha256":"072f4f4f7774737963ec79b7838fd2646ba6b7c2b7ba78800879d922c0c16463","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:00:45.902801Z","signature_b64":"5fbhOU3VDfSoRTWIYEO+qvFJ6sKUmw9LMpGIE82SKl9gqXYv1L3rzynRkI5alI/zWpfF+fROEQfRyajgQ1JFDA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"072f4f4f7774737963ec79b7838fd2646ba6b7c2b7ba78800879d922c0c16463","last_reissued_at":"2026-05-18T00:00:45.902448Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:00:45.902448Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1802.06252","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":"2026-05-18T00:00:45Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"LYhT52rqmgSZq9id/YilKZkA0Zui6ZrKLDjC42b2ofpF0wBcYDFtpCp9uRsm9u8wiVPsIfeHHMLidQPaL845CQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-05T18:33:52.161774Z"},"content_sha256":"5461679797a5108e0a866914aa0a7c2755d3dac23c64ce6434a802019b81c4d5","schema_version":"1.0","event_id":"sha256:5461679797a5108e0a866914aa0a7c2755d3dac23c64ce6434a802019b81c4d5"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:A4XU6T3XORZXSY7MPG3YHD6SMR","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Kernel-nulling for a robust direct interferometric detection of extrasolar planets","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.IM","authors_text":"Frantz Martinache, Michael J. Ireland","submitted_at":"2018-02-17T15:44:04Z","abstract_excerpt":"Combining the resolving power of long-baseline interferometry with the high-dynamic range capability of nulling still remains the only technique that can directly sense the presence of structures in the innermost regions of extrasolar planetary systems. Ultimately, the performance of any nuller architecture is constrained by the partial resolution of the on-axis star whose light it attempts to cancel out. However from the ground, the effective performance of nulling is dominated by residual time-varying instrumental phase and background errors that keep the instrument off the null. Our work in"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1802.06252","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"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T00:00:45Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"L3dmy7KUhqUSHurwgd0AynOWsR4JwJZNxnv7f/p8P7o3Ggv9N6iO6sKVFdNUi8FTaJBxzMizSUoY/GqjcutUAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-05T18:33:52.162129Z"},"content_sha256":"7d2b12bbe4f1e3484b948a571f024faeb34a977a731bae8873bf362e98acb7a8","schema_version":"1.0","event_id":"sha256:7d2b12bbe4f1e3484b948a571f024faeb34a977a731bae8873bf362e98acb7a8"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/A4XU6T3XORZXSY7MPG3YHD6SMR/bundle.json","state_url":"https://pith.science/pith/A4XU6T3XORZXSY7MPG3YHD6SMR/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/A4XU6T3XORZXSY7MPG3YHD6SMR/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":"2026-08-05T18:33:52Z","links":{"resolver":"https://pith.science/pith/A4XU6T3XORZXSY7MPG3YHD6SMR","bundle":"https://pith.science/pith/A4XU6T3XORZXSY7MPG3YHD6SMR/bundle.json","state":"https://pith.science/pith/A4XU6T3XORZXSY7MPG3YHD6SMR/state.json","well_known_bundle":"https://pith.science/.well-known/pith/A4XU6T3XORZXSY7MPG3YHD6SMR/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:A4XU6T3XORZXSY7MPG3YHD6SMR","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":"323b8d4dbcbe912b4b0a7b9c65dad62624d13b1d85fb3ea4790336fbdceb0de1","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-02-17T15:44:04Z","title_canon_sha256":"353fc6066381c2aef11a71b8d2e43ff7f34e37618aa8788c5a206374cf0e9f62"},"schema_version":"1.0","source":{"id":"1802.06252","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1802.06252","created_at":"2026-05-18T00:00:45Z"},{"alias_kind":"arxiv_version","alias_value":"1802.06252v2","created_at":"2026-05-18T00:00:45Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1802.06252","created_at":"2026-05-18T00:00:45Z"},{"alias_kind":"pith_short_12","alias_value":"A4XU6T3XORZX","created_at":"2026-05-18T12:32:13Z"},{"alias_kind":"pith_short_16","alias_value":"A4XU6T3XORZXSY7M","created_at":"2026-05-18T12:32:13Z"},{"alias_kind":"pith_short_8","alias_value":"A4XU6T3X","created_at":"2026-05-18T12:32:13Z"}],"graph_snapshots":[{"event_id":"sha256:7d2b12bbe4f1e3484b948a571f024faeb34a977a731bae8873bf362e98acb7a8","target":"graph","created_at":"2026-05-18T00:00:45Z","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":"Combining the resolving power of long-baseline interferometry with the high-dynamic range capability of nulling still remains the only technique that can directly sense the presence of structures in the innermost regions of extrasolar planetary systems. Ultimately, the performance of any nuller architecture is constrained by the partial resolution of the on-axis star whose light it attempts to cancel out. However from the ground, the effective performance of nulling is dominated by residual time-varying instrumental phase and background errors that keep the instrument off the null. Our work in","authors_text":"Frantz Martinache, Michael J. Ireland","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-02-17T15:44:04Z","title":"Kernel-nulling for a robust direct interferometric detection of extrasolar planets"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1802.06252","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":"sha256:5461679797a5108e0a866914aa0a7c2755d3dac23c64ce6434a802019b81c4d5","target":"record","created_at":"2026-05-18T00:00:45Z","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":"323b8d4dbcbe912b4b0a7b9c65dad62624d13b1d85fb3ea4790336fbdceb0de1","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-02-17T15:44:04Z","title_canon_sha256":"353fc6066381c2aef11a71b8d2e43ff7f34e37618aa8788c5a206374cf0e9f62"},"schema_version":"1.0","source":{"id":"1802.06252","kind":"arxiv","version":2}},"canonical_sha256":"072f4f4f7774737963ec79b7838fd2646ba6b7c2b7ba78800879d922c0c16463","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"072f4f4f7774737963ec79b7838fd2646ba6b7c2b7ba78800879d922c0c16463","first_computed_at":"2026-05-18T00:00:45.902448Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:00:45.902448Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"5fbhOU3VDfSoRTWIYEO+qvFJ6sKUmw9LMpGIE82SKl9gqXYv1L3rzynRkI5alI/zWpfF+fROEQfRyajgQ1JFDA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:00:45.902801Z","signed_message":"canonical_sha256_bytes"},"source_id":"1802.06252","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:5461679797a5108e0a866914aa0a7c2755d3dac23c64ce6434a802019b81c4d5","sha256:7d2b12bbe4f1e3484b948a571f024faeb34a977a731bae8873bf362e98acb7a8"],"state_sha256":"23d8f6915eeccac9bad25420754879679bd993001bf9ecc0c673b3cb9d4aef6e"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"c4mssDT8R/crHisdnT0M7O2xr0H8YVd1auhv/SCt1oSV8kNn4dE/SRiGfahpqXVYO8+TBbWCkBq+GDoe7ChPAg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-05T18:33:52.164564Z","bundle_sha256":"6c5b3b6434a73714de100b8129e98c2ce6b7f681ab975913ea801e12fed138db"}}