{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2009:UXSP25CFQFNIVAICV66PQI6BAK","short_pith_number":"pith:UXSP25CF","canonical_record":{"source":{"id":"0906.1718","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2009-06-09T13:08:07Z","cross_cats_sorted":[],"title_canon_sha256":"3670adb00e902e5de80683a8547f6e12207c73f8b7039d1f4720a351acf1952f","abstract_canon_sha256":"29c94a65f21333cbfb2bca75b04134f03ea95fbdd6bdfe92feba79816634ab29"},"schema_version":"1.0"},"canonical_sha256":"a5e4fd7445815a8a8102afbcf823c10292ca543125f2830266227f336f9af94a","source":{"kind":"arxiv","id":"0906.1718","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"0906.1718","created_at":"2026-07-04T15:43:29Z"},{"alias_kind":"arxiv_version","alias_value":"0906.1718v1","created_at":"2026-07-04T15:43:29Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0906.1718","created_at":"2026-07-04T15:43:29Z"},{"alias_kind":"pith_short_12","alias_value":"UXSP25CFQFNI","created_at":"2026-07-04T15:43:29Z"},{"alias_kind":"pith_short_16","alias_value":"UXSP25CFQFNIVAIC","created_at":"2026-07-04T15:43:29Z"},{"alias_kind":"pith_short_8","alias_value":"UXSP25CF","created_at":"2026-07-04T15:43:29Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2009:UXSP25CFQFNIVAICV66PQI6BAK","target":"record","payload":{"canonical_record":{"source":{"id":"0906.1718","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2009-06-09T13:08:07Z","cross_cats_sorted":[],"title_canon_sha256":"3670adb00e902e5de80683a8547f6e12207c73f8b7039d1f4720a351acf1952f","abstract_canon_sha256":"29c94a65f21333cbfb2bca75b04134f03ea95fbdd6bdfe92feba79816634ab29"},"schema_version":"1.0"},"canonical_sha256":"a5e4fd7445815a8a8102afbcf823c10292ca543125f2830266227f336f9af94a","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-04T15:43:29.692116Z","signature_b64":"JODsmAsOKEXHbOdBCVtXnqjjrzXkK3uRslvP+gKeC0RkNik/gag6EjK3WbwuX5kC84lfrzFkLye/644w2STcBA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"a5e4fd7445815a8a8102afbcf823c10292ca543125f2830266227f336f9af94a","last_reissued_at":"2026-07-04T15:43:29.691718Z","signature_status":"signed_v1","first_computed_at":"2026-07-04T15:43:29.691718Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"0906.1718","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":"2026-07-04T15:43:29Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"WNfOhd+3ihQjFoTLxpb+6DiwufJfkr9DOq4mMzrWLdwiNxAM0jsCfDhsI73MYqO4ttHZKZRq2qsRPYULFHCADA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-07T14:37:25.898067Z"},"content_sha256":"cfa9aabcaf8f74513abcd78b461b69e87bb6c05b51b38cf85371331f5c765615","schema_version":"1.0","event_id":"sha256:cfa9aabcaf8f74513abcd78b461b69e87bb6c05b51b38cf85371331f5c765615"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2009:UXSP25CFQFNIVAICV66PQI6BAK","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Reconstruction methods for acoustic particle detection in the deep sea using clusters of hydrophones","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.IM","authors_text":"A. Kappes, Ch. Naumann, C. Richardt, F. Schoeck, G. Anton, J. Hoessl, K. Graf, M. Neff, R. Lahmann, U. Katz","submitted_at":"2009-06-09T13:08:07Z","abstract_excerpt":"This article focuses on techniques for acoustic noise reduction, signal filters and source reconstruction. For noise reduction, bandpass filters and cross correlations are found to be efficient and fast ways to improve the signal to noise ratio and identify a possible neutrino-induced acoustic signal. The reconstruction of the position of an acoustic point source in the sea is performed by using small-volume clusters of hydrophones (about 1 cubic meter) for direction reconstruction by a beamforming algorithm. The directional information from a number of such clusters allows for position recons"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0906.1718","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/0906.1718/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":"2026-07-04T15:43:29Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"hyQPE8c8glNGoCRNJMGTqB+0pw1sbG6VxlJdB17SvgY25mh/szlS3+9SrcogHv1t6DoyDjKqrTvXUI09uZEuAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-07-07T14:37:25.898490Z"},"content_sha256":"e9a84c0513766d8606d3bfda9cf20c4b0a760ef2f483b66b88dcdd097766a4bf","schema_version":"1.0","event_id":"sha256:e9a84c0513766d8606d3bfda9cf20c4b0a760ef2f483b66b88dcdd097766a4bf"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/UXSP25CFQFNIVAICV66PQI6BAK/bundle.json","state_url":"https://pith.science/pith/UXSP25CFQFNIVAICV66PQI6BAK/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/UXSP25CFQFNIVAICV66PQI6BAK/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":"2026-07-07T14:37:25Z","links":{"resolver":"https://pith.science/pith/UXSP25CFQFNIVAICV66PQI6BAK","bundle":"https://pith.science/pith/UXSP25CFQFNIVAICV66PQI6BAK/bundle.json","state":"https://pith.science/pith/UXSP25CFQFNIVAICV66PQI6BAK/state.json","well_known_bundle":"https://pith.science/.well-known/pith/UXSP25CFQFNIVAICV66PQI6BAK/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2009:UXSP25CFQFNIVAICV66PQI6BAK","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":"29c94a65f21333cbfb2bca75b04134f03ea95fbdd6bdfe92feba79816634ab29","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2009-06-09T13:08:07Z","title_canon_sha256":"3670adb00e902e5de80683a8547f6e12207c73f8b7039d1f4720a351acf1952f"},"schema_version":"1.0","source":{"id":"0906.1718","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"0906.1718","created_at":"2026-07-04T15:43:29Z"},{"alias_kind":"arxiv_version","alias_value":"0906.1718v1","created_at":"2026-07-04T15:43:29Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0906.1718","created_at":"2026-07-04T15:43:29Z"},{"alias_kind":"pith_short_12","alias_value":"UXSP25CFQFNI","created_at":"2026-07-04T15:43:29Z"},{"alias_kind":"pith_short_16","alias_value":"UXSP25CFQFNIVAIC","created_at":"2026-07-04T15:43:29Z"},{"alias_kind":"pith_short_8","alias_value":"UXSP25CF","created_at":"2026-07-04T15:43:29Z"}],"graph_snapshots":[{"event_id":"sha256:e9a84c0513766d8606d3bfda9cf20c4b0a760ef2f483b66b88dcdd097766a4bf","target":"graph","created_at":"2026-07-04T15:43:29Z","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/0906.1718/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"This article focuses on techniques for acoustic noise reduction, signal filters and source reconstruction. For noise reduction, bandpass filters and cross correlations are found to be efficient and fast ways to improve the signal to noise ratio and identify a possible neutrino-induced acoustic signal. The reconstruction of the position of an acoustic point source in the sea is performed by using small-volume clusters of hydrophones (about 1 cubic meter) for direction reconstruction by a beamforming algorithm. The directional information from a number of such clusters allows for position recons","authors_text":"A. Kappes, Ch. Naumann, C. Richardt, F. Schoeck, G. Anton, J. Hoessl, K. Graf, M. Neff, R. Lahmann, U. Katz","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2009-06-09T13:08:07Z","title":"Reconstruction methods for acoustic particle detection in the deep sea using clusters of hydrophones"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0906.1718","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:cfa9aabcaf8f74513abcd78b461b69e87bb6c05b51b38cf85371331f5c765615","target":"record","created_at":"2026-07-04T15:43:29Z","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":"29c94a65f21333cbfb2bca75b04134f03ea95fbdd6bdfe92feba79816634ab29","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2009-06-09T13:08:07Z","title_canon_sha256":"3670adb00e902e5de80683a8547f6e12207c73f8b7039d1f4720a351acf1952f"},"schema_version":"1.0","source":{"id":"0906.1718","kind":"arxiv","version":1}},"canonical_sha256":"a5e4fd7445815a8a8102afbcf823c10292ca543125f2830266227f336f9af94a","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"a5e4fd7445815a8a8102afbcf823c10292ca543125f2830266227f336f9af94a","first_computed_at":"2026-07-04T15:43:29.691718Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-04T15:43:29.691718Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"JODsmAsOKEXHbOdBCVtXnqjjrzXkK3uRslvP+gKeC0RkNik/gag6EjK3WbwuX5kC84lfrzFkLye/644w2STcBA==","signature_status":"signed_v1","signed_at":"2026-07-04T15:43:29.692116Z","signed_message":"canonical_sha256_bytes"},"source_id":"0906.1718","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:cfa9aabcaf8f74513abcd78b461b69e87bb6c05b51b38cf85371331f5c765615","sha256:e9a84c0513766d8606d3bfda9cf20c4b0a760ef2f483b66b88dcdd097766a4bf"],"state_sha256":"4ae8268abadd684ee5f03275947a8ae46272a9f6df8ef72b05b9722ae67bad04"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"mg1pxJylshv871FYzLnGH7Bcs+G1d2cvKZfcwRp9a31qkGiI3HX+UBRB3fH2aMDntlqsBlU7EiHxO4Cxf3XnDQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-07-07T14:37:25.900469Z","bundle_sha256":"c25d8955aa0de2e550858545920a473244be934e7ebbb78acb589477df52e499"}}