{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2014:7PK3CXEYY3MDBYBOGDRHVGDFFR","short_pith_number":"pith:7PK3CXEY","schema_version":"1.0","canonical_sha256":"fbd5b15c98c6d830e02e30e27a98652c564bdde249de47b9c8c467bd288f8712","source":{"kind":"arxiv","id":"1406.2364","version":2},"attestation_state":"computed","paper":{"title":"A high-contrast coronagraph for earth-like exoplanet direct imaging: design and test","license":"http://creativecommons.org/licenses/by/3.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.IM","authors_text":"C. C. Liu, D. Q. Ren, G. Zhao, J. P. Dou, R. Chen, X. Zhang, Y. T. Zhu, Zh. Wu","submitted_at":"2014-06-09T21:23:52Z","abstract_excerpt":"The high-contrast coronagraph for direct imaging earth-like exoplanet at the visible needs a contrast of 10^(-10) at a small angular separation of 4 lambda/D or less. Here we report our recent laboratory experiment that is close to the limits. The test of the high-contrast imaging coronagraph is based on our step-transmission apodized filter. To achieve the goal, we use a liquid crystal array (LCA) as a phase corrector to create a dark hole based on our dedicated focal dark algorithm. We have suppressed the diffracted and speckle noise near the star point image to a level of 1.68 x 10^(-9) at "},"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":"1406.2364","kind":"arxiv","version":2},"metadata":{"license":"http://creativecommons.org/licenses/by/3.0/","primary_cat":"astro-ph.IM","submitted_at":"2014-06-09T21:23:52Z","cross_cats_sorted":[],"title_canon_sha256":"9742f896f1a2f54da446d7039f5dda46b50ec7c9a10009d9cd75f315234b0806","abstract_canon_sha256":"b051b2756ff1dee8611a685915dcf21cd3582f8497130314baf687dd4288cf07"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:49:55.390859Z","signature_b64":"I9yx75GgTJB+sIODaXiqRag2PMg6FLkoUCvSmYVqZNq5n1JScT6ydMdOh+CoodSV1Ra3EoCXEpbShlxCKRqEBg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"fbd5b15c98c6d830e02e30e27a98652c564bdde249de47b9c8c467bd288f8712","last_reissued_at":"2026-05-18T02:49:55.390140Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:49:55.390140Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"A high-contrast coronagraph for earth-like exoplanet direct imaging: design and test","license":"http://creativecommons.org/licenses/by/3.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.IM","authors_text":"C. C. Liu, D. Q. Ren, G. Zhao, J. P. Dou, R. Chen, X. Zhang, Y. T. Zhu, Zh. Wu","submitted_at":"2014-06-09T21:23:52Z","abstract_excerpt":"The high-contrast coronagraph for direct imaging earth-like exoplanet at the visible needs a contrast of 10^(-10) at a small angular separation of 4 lambda/D or less. Here we report our recent laboratory experiment that is close to the limits. The test of the high-contrast imaging coronagraph is based on our step-transmission apodized filter. To achieve the goal, we use a liquid crystal array (LCA) as a phase corrector to create a dark hole based on our dedicated focal dark algorithm. We have suppressed the diffracted and speckle noise near the star point image to a level of 1.68 x 10^(-9) at "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1406.2364","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"},"aliases":[{"alias_kind":"arxiv","alias_value":"1406.2364","created_at":"2026-05-18T02:49:55.390236+00:00"},{"alias_kind":"arxiv_version","alias_value":"1406.2364v2","created_at":"2026-05-18T02:49:55.390236+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1406.2364","created_at":"2026-05-18T02:49:55.390236+00:00"},{"alias_kind":"pith_short_12","alias_value":"7PK3CXEYY3MD","created_at":"2026-05-18T12:28:19.803747+00:00"},{"alias_kind":"pith_short_16","alias_value":"7PK3CXEYY3MDBYBO","created_at":"2026-05-18T12:28:19.803747+00:00"},{"alias_kind":"pith_short_8","alias_value":"7PK3CXEY","created_at":"2026-05-18T12:28:19.803747+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/7PK3CXEYY3MDBYBOGDRHVGDFFR","json":"https://pith.science/pith/7PK3CXEYY3MDBYBOGDRHVGDFFR.json","graph_json":"https://pith.science/api/pith-number/7PK3CXEYY3MDBYBOGDRHVGDFFR/graph.json","events_json":"https://pith.science/api/pith-number/7PK3CXEYY3MDBYBOGDRHVGDFFR/events.json","paper":"https://pith.science/paper/7PK3CXEY"},"agent_actions":{"view_html":"https://pith.science/pith/7PK3CXEYY3MDBYBOGDRHVGDFFR","download_json":"https://pith.science/pith/7PK3CXEYY3MDBYBOGDRHVGDFFR.json","view_paper":"https://pith.science/paper/7PK3CXEY","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=1406.2364&json=true","fetch_graph":"https://pith.science/api/pith-number/7PK3CXEYY3MDBYBOGDRHVGDFFR/graph.json","fetch_events":"https://pith.science/api/pith-number/7PK3CXEYY3MDBYBOGDRHVGDFFR/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/7PK3CXEYY3MDBYBOGDRHVGDFFR/action/timestamp_anchor","attest_storage":"https://pith.science/pith/7PK3CXEYY3MDBYBOGDRHVGDFFR/action/storage_attestation","attest_author":"https://pith.science/pith/7PK3CXEYY3MDBYBOGDRHVGDFFR/action/author_attestation","sign_citation":"https://pith.science/pith/7PK3CXEYY3MDBYBOGDRHVGDFFR/action/citation_signature","submit_replication":"https://pith.science/pith/7PK3CXEYY3MDBYBOGDRHVGDFFR/action/replication_record"}},"created_at":"2026-05-18T02:49:55.390236+00:00","updated_at":"2026-05-18T02:49:55.390236+00:00"}