{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:JH26WVHJ253L74BB7UENL2TTIB","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":"64f40172e57be9806bc185ba71e3f24501e51751a27cfb2d9953c298495b086a","cross_cats_sorted":["astro-ph.EP","physics.optics"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2019-01-13T23:50:07Z","title_canon_sha256":"fc452c9582c10cc6988cb64d305ba6cc998bd7a7ab42bb052376538629356635"},"schema_version":"1.0","source":{"id":"1901.04090","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1901.04090","created_at":"2026-05-17T23:53:49Z"},{"alias_kind":"arxiv_version","alias_value":"1901.04090v2","created_at":"2026-05-17T23:53:49Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1901.04090","created_at":"2026-05-17T23:53:49Z"},{"alias_kind":"pith_short_12","alias_value":"JH26WVHJ253L","created_at":"2026-05-18T12:33:21Z"},{"alias_kind":"pith_short_16","alias_value":"JH26WVHJ253L74BB","created_at":"2026-05-18T12:33:21Z"},{"alias_kind":"pith_short_8","alias_value":"JH26WVHJ","created_at":"2026-05-18T12:33:21Z"}],"graph_snapshots":[{"event_id":"sha256:0919ac6d13a8c9e22f4b71429cc924973636728a670c7ca9fe4c55b7400c3759","target":"graph","created_at":"2026-05-17T23:53:49Z","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":"Reference star differential imaging (RDI) is a powerful strategy for high contrast imaging. Using example observations taken with the vortex coronagraph mode of Keck/NIRC2 in $L^\\prime$ band, we demonstrate that RDI provides improved sensitivity to point sources at small angular separations compared to angular differential imaging (ADI). Applying RDI to images of the low-mass stellar companions HIP 79124 C (192 mas separation, $\\Delta L^\\prime$=4.01) and HIP 78233 B (141 mas separation, $\\Delta L^\\prime$=4.78), the latter a first imaging detection, increases the significance of their detection","authors_text":"Carlos Gomez Gonzalez, Dimitri Mawet, Elodie Choquet, Elsa huby, Eugene Serabyn, Garreth Ruane, Henry Ngo, Keith Matthews, Maddalena Reggiani, Nicole Wallack, Olivier Absil, Therese Cook, Tiffany Meshkat, W. Jerry Xuan","cross_cats":["astro-ph.EP","physics.optics"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2019-01-13T23:50:07Z","title":"Reference star differential imaging of close-in companions and circumstellar disks with the NIRC2 vortex coronagraph at W.M. Keck Observatory"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1901.04090","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":"sha256:8fa04b80c5064ea3843ede493ef5f0c9e3642ec658f50c57dd8a3343dfad6841","target":"record","created_at":"2026-05-17T23:53:49Z","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":"64f40172e57be9806bc185ba71e3f24501e51751a27cfb2d9953c298495b086a","cross_cats_sorted":["astro-ph.EP","physics.optics"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2019-01-13T23:50:07Z","title_canon_sha256":"fc452c9582c10cc6988cb64d305ba6cc998bd7a7ab42bb052376538629356635"},"schema_version":"1.0","source":{"id":"1901.04090","kind":"arxiv","version":2}},"canonical_sha256":"49f5eb54e9d776bff021fd08d5ea734052177e0a5b52af7e892bef17971bbff0","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"49f5eb54e9d776bff021fd08d5ea734052177e0a5b52af7e892bef17971bbff0","first_computed_at":"2026-05-17T23:53:49.616703Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:53:49.616703Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"YObv4ZlhxS6WvcCeMzdLRec3GOtfngLtDws8bkqK6NVbc64x+jIz+47b35jSo7LbXLYxJj7GJh4Vwwy83/EWCw==","signature_status":"signed_v1","signed_at":"2026-05-17T23:53:49.617371Z","signed_message":"canonical_sha256_bytes"},"source_id":"1901.04090","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:8fa04b80c5064ea3843ede493ef5f0c9e3642ec658f50c57dd8a3343dfad6841","sha256:0919ac6d13a8c9e22f4b71429cc924973636728a670c7ca9fe4c55b7400c3759"],"state_sha256":"f52c118a0391040a34d31142a034f5e9d5166e8ae5f3a353d53d7a85394cea07"}