{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2026:FOVQUFDPYBDLBJN6N3W2XFCTHD","short_pith_number":"pith:FOVQUFDP","canonical_record":{"source":{"id":"2606.25541","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2026-06-24T08:18:32Z","cross_cats_sorted":["physics.comp-ph"],"title_canon_sha256":"1dbaa43bba870c4aa64ca92fd612b9aa97c737dc6af4183accd19ad984a47b17","abstract_canon_sha256":"ef36625f3aa87f5fe33b01dfb4df35805e9d1ce738db47cc6bff807128e77dcd"},"schema_version":"1.0"},"canonical_sha256":"2bab0a146fc046b0a5be6eedab945338fb07847f05eb4c9adf9025bc8f9005f1","source":{"kind":"arxiv","id":"2606.25541","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2606.25541","created_at":"2026-06-25T01:18:08Z"},{"alias_kind":"arxiv_version","alias_value":"2606.25541v1","created_at":"2026-06-25T01:18:08Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2606.25541","created_at":"2026-06-25T01:18:08Z"},{"alias_kind":"pith_short_12","alias_value":"FOVQUFDPYBDL","created_at":"2026-06-25T01:18:08Z"},{"alias_kind":"pith_short_16","alias_value":"FOVQUFDPYBDLBJN6","created_at":"2026-06-25T01:18:08Z"},{"alias_kind":"pith_short_8","alias_value":"FOVQUFDP","created_at":"2026-06-25T01:18:08Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2026:FOVQUFDPYBDLBJN6N3W2XFCTHD","target":"record","payload":{"canonical_record":{"source":{"id":"2606.25541","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2026-06-24T08:18:32Z","cross_cats_sorted":["physics.comp-ph"],"title_canon_sha256":"1dbaa43bba870c4aa64ca92fd612b9aa97c737dc6af4183accd19ad984a47b17","abstract_canon_sha256":"ef36625f3aa87f5fe33b01dfb4df35805e9d1ce738db47cc6bff807128e77dcd"},"schema_version":"1.0"},"canonical_sha256":"2bab0a146fc046b0a5be6eedab945338fb07847f05eb4c9adf9025bc8f9005f1","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-06-25T01:18:08.332850Z","signature_b64":"UtedBJLMDWwOidd0yzNPIIY8KqRwMYu9OKLRC4YUsRcYrWvVjx6EgokzOtLb6dkpSh2DFGt/Jphow2yCQoWDBw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"2bab0a146fc046b0a5be6eedab945338fb07847f05eb4c9adf9025bc8f9005f1","last_reissued_at":"2026-06-25T01:18:08.332434Z","signature_status":"signed_v1","first_computed_at":"2026-06-25T01:18:08.332434Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2606.25541","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":"2026-06-25T01:18:08Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"hJNcvPahoEncsJp1w+67Zjaxt2skI8d7uMG30hw1wGikhyclrJunjHt4jjDiVDzIfO2M8oQOQgq35NM4ehDRBQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-27T16:10:53.268915Z"},"content_sha256":"98c455374adf40cfdfd2e31b8898b1be1a4e4c1aab12bed95a24db513ac7b3d7","schema_version":"1.0","event_id":"sha256:98c455374adf40cfdfd2e31b8898b1be1a4e4c1aab12bed95a24db513ac7b3d7"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2026:FOVQUFDPYBDLBJN6N3W2XFCTHD","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Pseudo-spectral frequency-domain method with background field decomposition and Green's function preconditioner for electromagnetic scattering problem in EUV lithography","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["physics.comp-ph"],"primary_cat":"physics.optics","authors_text":"Doyun Kim, Seungjin Lee, Werner Gillijns","submitted_at":"2026-06-24T08:18:32Z","abstract_excerpt":"We provide an accelerated computational framework to solve electromagnetic scattering problems in planarly layered media arising from extreme ultraviolet (EUV) lithography. To achieve this, we reformulate the EUV scattering problem into a scattering problem on a homogeneous background, in which the electromagnetic contribution of the layered media is captured by a recursively updated reflection of the layered stack. The system is numerically solved by employing the pseudo-spectral frequency-domain method paired with an iterative solver, whose iterative convergence is expedited by a free-space "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2606.25541","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/2606.25541/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":"2026-06-25T01:18:08Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"3zoCpJ+rx8i5Qwd0ywfxmqFagYlsPLGGRjLIx5ITKk4qqqOpu+e+b+aB9xrN0+8rboFhmY/YtGO4QhrMETj2AQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-27T16:10:53.269287Z"},"content_sha256":"476c3f3649c54d9e968d94ad3c89286a38881b1397eb30914eb6d43f1a49e068","schema_version":"1.0","event_id":"sha256:476c3f3649c54d9e968d94ad3c89286a38881b1397eb30914eb6d43f1a49e068"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/FOVQUFDPYBDLBJN6N3W2XFCTHD/bundle.json","state_url":"https://pith.science/pith/FOVQUFDPYBDLBJN6N3W2XFCTHD/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/FOVQUFDPYBDLBJN6N3W2XFCTHD/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":"2026-06-27T16:10:53Z","links":{"resolver":"https://pith.science/pith/FOVQUFDPYBDLBJN6N3W2XFCTHD","bundle":"https://pith.science/pith/FOVQUFDPYBDLBJN6N3W2XFCTHD/bundle.json","state":"https://pith.science/pith/FOVQUFDPYBDLBJN6N3W2XFCTHD/state.json","well_known_bundle":"https://pith.science/.well-known/pith/FOVQUFDPYBDLBJN6N3W2XFCTHD/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2026:FOVQUFDPYBDLBJN6N3W2XFCTHD","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":"ef36625f3aa87f5fe33b01dfb4df35805e9d1ce738db47cc6bff807128e77dcd","cross_cats_sorted":["physics.comp-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2026-06-24T08:18:32Z","title_canon_sha256":"1dbaa43bba870c4aa64ca92fd612b9aa97c737dc6af4183accd19ad984a47b17"},"schema_version":"1.0","source":{"id":"2606.25541","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2606.25541","created_at":"2026-06-25T01:18:08Z"},{"alias_kind":"arxiv_version","alias_value":"2606.25541v1","created_at":"2026-06-25T01:18:08Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2606.25541","created_at":"2026-06-25T01:18:08Z"},{"alias_kind":"pith_short_12","alias_value":"FOVQUFDPYBDL","created_at":"2026-06-25T01:18:08Z"},{"alias_kind":"pith_short_16","alias_value":"FOVQUFDPYBDLBJN6","created_at":"2026-06-25T01:18:08Z"},{"alias_kind":"pith_short_8","alias_value":"FOVQUFDP","created_at":"2026-06-25T01:18:08Z"}],"graph_snapshots":[{"event_id":"sha256:476c3f3649c54d9e968d94ad3c89286a38881b1397eb30914eb6d43f1a49e068","target":"graph","created_at":"2026-06-25T01:18:08Z","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/2606.25541/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"We provide an accelerated computational framework to solve electromagnetic scattering problems in planarly layered media arising from extreme ultraviolet (EUV) lithography. To achieve this, we reformulate the EUV scattering problem into a scattering problem on a homogeneous background, in which the electromagnetic contribution of the layered media is captured by a recursively updated reflection of the layered stack. The system is numerically solved by employing the pseudo-spectral frequency-domain method paired with an iterative solver, whose iterative convergence is expedited by a free-space ","authors_text":"Doyun Kim, Seungjin Lee, Werner Gillijns","cross_cats":["physics.comp-ph"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2026-06-24T08:18:32Z","title":"Pseudo-spectral frequency-domain method with background field decomposition and Green's function preconditioner for electromagnetic scattering problem in EUV lithography"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2606.25541","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":"sha256:98c455374adf40cfdfd2e31b8898b1be1a4e4c1aab12bed95a24db513ac7b3d7","target":"record","created_at":"2026-06-25T01:18:08Z","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":"ef36625f3aa87f5fe33b01dfb4df35805e9d1ce738db47cc6bff807128e77dcd","cross_cats_sorted":["physics.comp-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.optics","submitted_at":"2026-06-24T08:18:32Z","title_canon_sha256":"1dbaa43bba870c4aa64ca92fd612b9aa97c737dc6af4183accd19ad984a47b17"},"schema_version":"1.0","source":{"id":"2606.25541","kind":"arxiv","version":1}},"canonical_sha256":"2bab0a146fc046b0a5be6eedab945338fb07847f05eb4c9adf9025bc8f9005f1","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"2bab0a146fc046b0a5be6eedab945338fb07847f05eb4c9adf9025bc8f9005f1","first_computed_at":"2026-06-25T01:18:08.332434Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-06-25T01:18:08.332434Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"UtedBJLMDWwOidd0yzNPIIY8KqRwMYu9OKLRC4YUsRcYrWvVjx6EgokzOtLb6dkpSh2DFGt/Jphow2yCQoWDBw==","signature_status":"signed_v1","signed_at":"2026-06-25T01:18:08.332850Z","signed_message":"canonical_sha256_bytes"},"source_id":"2606.25541","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:98c455374adf40cfdfd2e31b8898b1be1a4e4c1aab12bed95a24db513ac7b3d7","sha256:476c3f3649c54d9e968d94ad3c89286a38881b1397eb30914eb6d43f1a49e068"],"state_sha256":"4cd362fe92b4471f4f3a302981bfed42789497c0f14123eb4bbc9df4f368e7f3"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"k7JKNIP+y/PJTlODHhFkR7tLiy1Nb6P3gYbp+hAjlVc3sZqaRNExBW2hsOJW0sq+dTFdXwCH68Pxy8OQ3LhkCQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-27T16:10:53.271279Z","bundle_sha256":"569bbf60f0b775421a4183368224721444ed98712302e876acfbbc4a6404c4d7"}}