{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2020:64I24CLQEPJ7U3LJDC2H746GQD","short_pith_number":"pith:64I24CLQ","canonical_record":{"source":{"id":"2012.15836","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2020-12-31T18:54:09Z","cross_cats_sorted":[],"title_canon_sha256":"11be9210db4499b9b3102aa608938f22ab8a693e633a3fc950150e1d6490e71a","abstract_canon_sha256":"934d8751705067e7bbeae8e736771f6c78e71e0f6b52a40d60f164533e6f9f3a"},"schema_version":"1.0"},"canonical_sha256":"f711ae097023d3fa6d6918b47ff3c680d03f13c65202f5edbcaea4dedd1b3568","source":{"kind":"arxiv","id":"2012.15836","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2012.15836","created_at":"2026-07-05T02:03:21Z"},{"alias_kind":"arxiv_version","alias_value":"2012.15836v1","created_at":"2026-07-05T02:03:21Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2012.15836","created_at":"2026-07-05T02:03:21Z"},{"alias_kind":"pith_short_12","alias_value":"64I24CLQEPJ7","created_at":"2026-07-05T02:03:21Z"},{"alias_kind":"pith_short_16","alias_value":"64I24CLQEPJ7U3LJ","created_at":"2026-07-05T02:03:21Z"},{"alias_kind":"pith_short_8","alias_value":"64I24CLQ","created_at":"2026-07-05T02:03:21Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2020:64I24CLQEPJ7U3LJDC2H746GQD","target":"record","payload":{"canonical_record":{"source":{"id":"2012.15836","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2020-12-31T18:54:09Z","cross_cats_sorted":[],"title_canon_sha256":"11be9210db4499b9b3102aa608938f22ab8a693e633a3fc950150e1d6490e71a","abstract_canon_sha256":"934d8751705067e7bbeae8e736771f6c78e71e0f6b52a40d60f164533e6f9f3a"},"schema_version":"1.0"},"canonical_sha256":"f711ae097023d3fa6d6918b47ff3c680d03f13c65202f5edbcaea4dedd1b3568","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T02:03:21.846450Z","signature_b64":"0dDUQpcy6hSwGlEz6OGpQpFUR0J/1ZRdHXMumX41WQGUsaW99GUSEXRw+hPECp4bhxmaZcwveOmLa5bjQaoQDA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"f711ae097023d3fa6d6918b47ff3c680d03f13c65202f5edbcaea4dedd1b3568","last_reissued_at":"2026-07-05T02:03:21.846030Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T02:03:21.846030Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2012.15836","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":"2026-07-05T02:03:21Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"HANkYrwvr48L7QHQmTry7v+KYvNoSnvXSrHz7A6W+rBuq52F/FJIi21m4zqpFxvxOAJPOMqtCAbv+y62ek2UCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-06T19:10:06.361978Z"},"content_sha256":"ab1deba9dfe22401bea6ef1563bcc8a62d541e47a8e0f352f34e45c8ce7a4d0d","schema_version":"1.0","event_id":"sha256:ab1deba9dfe22401bea6ef1563bcc8a62d541e47a8e0f352f34e45c8ce7a4d0d"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2020:64I24CLQEPJ7U3LJDC2H746GQD","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Principled point-source detection in collections of astronomical images","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.IM","authors_text":"David W. Hogg, Dustin Lang","submitted_at":"2020-12-31T18:54:09Z","abstract_excerpt":"We review the well-known matched filter method for the detection of point sources in astronomical images. This is shown to be optimal (that is, to saturate the Cramer--Rao bound) under stated conditions that are very strong: an isolated source in background-dominated imaging with perfectly known background level, point-spread function, and noise models. We show that the matched filter produces a maximum-likelihood estimate of the brightness of a purported point source, and this leads to a simple way to combine multiple images---taken through the same bandpass filter but with different noise le"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2012.15836","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2012.15836/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":"2026-07-05T02:03:21Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Wk94rjta1KZLS54btCEzDcbID1p93oz5a/T1VgeOZgeWCQvVg5pkGwVthIh3O0odJH35kTULhyuuAm/iSHVbBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-06T19:10:06.362468Z"},"content_sha256":"a576def53a53aa5c815e1bde64ecaf8a0d2877bdad3855f7e2ac09560c0d81c0","schema_version":"1.0","event_id":"sha256:a576def53a53aa5c815e1bde64ecaf8a0d2877bdad3855f7e2ac09560c0d81c0"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/64I24CLQEPJ7U3LJDC2H746GQD/bundle.json","state_url":"https://pith.science/pith/64I24CLQEPJ7U3LJDC2H746GQD/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/64I24CLQEPJ7U3LJDC2H746GQD/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":"2026-08-06T19:10:06Z","links":{"resolver":"https://pith.science/pith/64I24CLQEPJ7U3LJDC2H746GQD","bundle":"https://pith.science/pith/64I24CLQEPJ7U3LJDC2H746GQD/bundle.json","state":"https://pith.science/pith/64I24CLQEPJ7U3LJDC2H746GQD/state.json","well_known_bundle":"https://pith.science/.well-known/pith/64I24CLQEPJ7U3LJDC2H746GQD/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2020:64I24CLQEPJ7U3LJDC2H746GQD","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":"934d8751705067e7bbeae8e736771f6c78e71e0f6b52a40d60f164533e6f9f3a","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2020-12-31T18:54:09Z","title_canon_sha256":"11be9210db4499b9b3102aa608938f22ab8a693e633a3fc950150e1d6490e71a"},"schema_version":"1.0","source":{"id":"2012.15836","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2012.15836","created_at":"2026-07-05T02:03:21Z"},{"alias_kind":"arxiv_version","alias_value":"2012.15836v1","created_at":"2026-07-05T02:03:21Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2012.15836","created_at":"2026-07-05T02:03:21Z"},{"alias_kind":"pith_short_12","alias_value":"64I24CLQEPJ7","created_at":"2026-07-05T02:03:21Z"},{"alias_kind":"pith_short_16","alias_value":"64I24CLQEPJ7U3LJ","created_at":"2026-07-05T02:03:21Z"},{"alias_kind":"pith_short_8","alias_value":"64I24CLQ","created_at":"2026-07-05T02:03:21Z"}],"graph_snapshots":[{"event_id":"sha256:a576def53a53aa5c815e1bde64ecaf8a0d2877bdad3855f7e2ac09560c0d81c0","target":"graph","created_at":"2026-07-05T02:03:21Z","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/2012.15836/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"We review the well-known matched filter method for the detection of point sources in astronomical images. This is shown to be optimal (that is, to saturate the Cramer--Rao bound) under stated conditions that are very strong: an isolated source in background-dominated imaging with perfectly known background level, point-spread function, and noise models. We show that the matched filter produces a maximum-likelihood estimate of the brightness of a purported point source, and this leads to a simple way to combine multiple images---taken through the same bandpass filter but with different noise le","authors_text":"David W. Hogg, Dustin Lang","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2020-12-31T18:54:09Z","title":"Principled point-source detection in collections of astronomical images"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2012.15836","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:ab1deba9dfe22401bea6ef1563bcc8a62d541e47a8e0f352f34e45c8ce7a4d0d","target":"record","created_at":"2026-07-05T02:03:21Z","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":"934d8751705067e7bbeae8e736771f6c78e71e0f6b52a40d60f164533e6f9f3a","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2020-12-31T18:54:09Z","title_canon_sha256":"11be9210db4499b9b3102aa608938f22ab8a693e633a3fc950150e1d6490e71a"},"schema_version":"1.0","source":{"id":"2012.15836","kind":"arxiv","version":1}},"canonical_sha256":"f711ae097023d3fa6d6918b47ff3c680d03f13c65202f5edbcaea4dedd1b3568","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"f711ae097023d3fa6d6918b47ff3c680d03f13c65202f5edbcaea4dedd1b3568","first_computed_at":"2026-07-05T02:03:21.846030Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T02:03:21.846030Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"0dDUQpcy6hSwGlEz6OGpQpFUR0J/1ZRdHXMumX41WQGUsaW99GUSEXRw+hPECp4bhxmaZcwveOmLa5bjQaoQDA==","signature_status":"signed_v1","signed_at":"2026-07-05T02:03:21.846450Z","signed_message":"canonical_sha256_bytes"},"source_id":"2012.15836","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:ab1deba9dfe22401bea6ef1563bcc8a62d541e47a8e0f352f34e45c8ce7a4d0d","sha256:a576def53a53aa5c815e1bde64ecaf8a0d2877bdad3855f7e2ac09560c0d81c0"],"state_sha256":"722ddc128d6d8c2a6cb679a74f0224a5326ac34f6b954bde5b29808bb271a326"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"/hVuDP0JV1WTY/m+AH3Th2BHw0X2QZVz7d+PYHjaPG3K5pBuiciDNCiE48lIoeGr7/7n/LIf2xlBAo4YS2qBDg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-06T19:10:06.366226Z","bundle_sha256":"38e53990410f2a6f0c24772345db364c623f8c1826c55869aa5469629541703d"}}