{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2016:TTQZR6S5CD3NYBRW46JTQ3XVWX","short_pith_number":"pith:TTQZR6S5","canonical_record":{"source":{"id":"1602.00402","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2016-02-01T06:41:01Z","cross_cats_sorted":[],"title_canon_sha256":"b4871a411105bb0066ffbbcaeed469ae4147129d1db6943c8e1715fe068caa0a","abstract_canon_sha256":"15d756a2fc080d1401d8b3bf90738767573fdc597774d45eb65862ddc93a5e05"},"schema_version":"1.0"},"canonical_sha256":"9ce198fa5d10f6dc0636e793386ef5b5cd3118f528e79222739daab391f313be","source":{"kind":"arxiv","id":"1602.00402","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1602.00402","created_at":"2026-05-18T01:12:16Z"},{"alias_kind":"arxiv_version","alias_value":"1602.00402v2","created_at":"2026-05-18T01:12:16Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1602.00402","created_at":"2026-05-18T01:12:16Z"},{"alias_kind":"pith_short_12","alias_value":"TTQZR6S5CD3N","created_at":"2026-05-18T12:30:46Z"},{"alias_kind":"pith_short_16","alias_value":"TTQZR6S5CD3NYBRW","created_at":"2026-05-18T12:30:46Z"},{"alias_kind":"pith_short_8","alias_value":"TTQZR6S5","created_at":"2026-05-18T12:30:46Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2016:TTQZR6S5CD3NYBRW46JTQ3XVWX","target":"record","payload":{"canonical_record":{"source":{"id":"1602.00402","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2016-02-01T06:41:01Z","cross_cats_sorted":[],"title_canon_sha256":"b4871a411105bb0066ffbbcaeed469ae4147129d1db6943c8e1715fe068caa0a","abstract_canon_sha256":"15d756a2fc080d1401d8b3bf90738767573fdc597774d45eb65862ddc93a5e05"},"schema_version":"1.0"},"canonical_sha256":"9ce198fa5d10f6dc0636e793386ef5b5cd3118f528e79222739daab391f313be","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:12:16.847063Z","signature_b64":"0Ze+ql7p1st+K4Qh4LAGxHp4uOALqxn/J5yrWltSAV87T3tNZgl2KnO2oeoRa+niqfDmyF616Tf5LojilqYXCA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"9ce198fa5d10f6dc0636e793386ef5b5cd3118f528e79222739daab391f313be","last_reissued_at":"2026-05-18T01:12:16.846729Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:12:16.846729Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1602.00402","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T01:12:16Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"zoM0t1EUA9Qzh30NFDEYHHL1l1EtGzF172ln/R0tfWefauwvhefE92GoluanN6FdMwqjfbaxVsd0H2tHzx4BBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-08T02:08:54.064294Z"},"content_sha256":"71c2b4c42e115a3530eae82afa07b7ad2439d17680e48efcd18e29897b6772c5","schema_version":"1.0","event_id":"sha256:71c2b4c42e115a3530eae82afa07b7ad2439d17680e48efcd18e29897b6772c5"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2016:TTQZR6S5CD3NYBRW46JTQ3XVWX","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Recent Developments in Measuring Signal and Noise in Phased Array Feeds at CSIRO","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.IM","authors_text":"A. P. Chippendale, A. W. Hotan, D. B. Hayman, D. McConnell, K. Bannister, K. W. Smart, N. Nikolic, R. D. Shaw, S. G. Hay","submitted_at":"2016-02-01T06:41:01Z","abstract_excerpt":"We describe recent developments in measuring both signal and noise in phased array feeds for radio astronomy at CSIRO. We introduce new techniques including aperture array noise measurements with beamforming weights matched to a reflector's focal field. Weights are calculated via antenna-range and in-reflector measurements. We also describe the separation of system temperature and aperture efficiency via drift scans."},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1602.00402","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"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T01:12:16Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"4/yv+fohT7ai0cChA4bC7CcDnaMJd8c6OgN+/Xz+AOrV9Gut/N4a0nQD4RCzXDbEwGRX9GvUeKbHg4XgOoSICw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-08T02:08:54.064976Z"},"content_sha256":"ed186307705d0e361f8381ab7795c657c3adaf3d6b54a4f4133ae3a1acda6e6b","schema_version":"1.0","event_id":"sha256:ed186307705d0e361f8381ab7795c657c3adaf3d6b54a4f4133ae3a1acda6e6b"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/TTQZR6S5CD3NYBRW46JTQ3XVWX/bundle.json","state_url":"https://pith.science/pith/TTQZR6S5CD3NYBRW46JTQ3XVWX/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/TTQZR6S5CD3NYBRW46JTQ3XVWX/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":"2026-06-08T02:08:54Z","links":{"resolver":"https://pith.science/pith/TTQZR6S5CD3NYBRW46JTQ3XVWX","bundle":"https://pith.science/pith/TTQZR6S5CD3NYBRW46JTQ3XVWX/bundle.json","state":"https://pith.science/pith/TTQZR6S5CD3NYBRW46JTQ3XVWX/state.json","well_known_bundle":"https://pith.science/.well-known/pith/TTQZR6S5CD3NYBRW46JTQ3XVWX/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2016:TTQZR6S5CD3NYBRW46JTQ3XVWX","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":"15d756a2fc080d1401d8b3bf90738767573fdc597774d45eb65862ddc93a5e05","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2016-02-01T06:41:01Z","title_canon_sha256":"b4871a411105bb0066ffbbcaeed469ae4147129d1db6943c8e1715fe068caa0a"},"schema_version":"1.0","source":{"id":"1602.00402","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1602.00402","created_at":"2026-05-18T01:12:16Z"},{"alias_kind":"arxiv_version","alias_value":"1602.00402v2","created_at":"2026-05-18T01:12:16Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1602.00402","created_at":"2026-05-18T01:12:16Z"},{"alias_kind":"pith_short_12","alias_value":"TTQZR6S5CD3N","created_at":"2026-05-18T12:30:46Z"},{"alias_kind":"pith_short_16","alias_value":"TTQZR6S5CD3NYBRW","created_at":"2026-05-18T12:30:46Z"},{"alias_kind":"pith_short_8","alias_value":"TTQZR6S5","created_at":"2026-05-18T12:30:46Z"}],"graph_snapshots":[{"event_id":"sha256:ed186307705d0e361f8381ab7795c657c3adaf3d6b54a4f4133ae3a1acda6e6b","target":"graph","created_at":"2026-05-18T01:12:16Z","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":"We describe recent developments in measuring both signal and noise in phased array feeds for radio astronomy at CSIRO. We introduce new techniques including aperture array noise measurements with beamforming weights matched to a reflector's focal field. Weights are calculated via antenna-range and in-reflector measurements. We also describe the separation of system temperature and aperture efficiency via drift scans.","authors_text":"A. P. Chippendale, A. W. Hotan, D. B. Hayman, D. McConnell, K. Bannister, K. W. Smart, N. Nikolic, R. D. Shaw, S. G. Hay","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2016-02-01T06:41:01Z","title":"Recent Developments in Measuring Signal and Noise in Phased Array Feeds at CSIRO"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1602.00402","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":"sha256:71c2b4c42e115a3530eae82afa07b7ad2439d17680e48efcd18e29897b6772c5","target":"record","created_at":"2026-05-18T01:12:16Z","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":"15d756a2fc080d1401d8b3bf90738767573fdc597774d45eb65862ddc93a5e05","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2016-02-01T06:41:01Z","title_canon_sha256":"b4871a411105bb0066ffbbcaeed469ae4147129d1db6943c8e1715fe068caa0a"},"schema_version":"1.0","source":{"id":"1602.00402","kind":"arxiv","version":2}},"canonical_sha256":"9ce198fa5d10f6dc0636e793386ef5b5cd3118f528e79222739daab391f313be","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"9ce198fa5d10f6dc0636e793386ef5b5cd3118f528e79222739daab391f313be","first_computed_at":"2026-05-18T01:12:16.846729Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:12:16.846729Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"0Ze+ql7p1st+K4Qh4LAGxHp4uOALqxn/J5yrWltSAV87T3tNZgl2KnO2oeoRa+niqfDmyF616Tf5LojilqYXCA==","signature_status":"signed_v1","signed_at":"2026-05-18T01:12:16.847063Z","signed_message":"canonical_sha256_bytes"},"source_id":"1602.00402","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:71c2b4c42e115a3530eae82afa07b7ad2439d17680e48efcd18e29897b6772c5","sha256:ed186307705d0e361f8381ab7795c657c3adaf3d6b54a4f4133ae3a1acda6e6b"],"state_sha256":"212cdf1b6a4000f61883914d1e9a5537805dc55f9aaeb7ae0977ea15807910b5"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"u7XotFnOR/ZY/qBKrkqEhbNuTMwCWX4KBvMcD/cLojlTlsfUOMXaeU2ylFx4o+UMo4w/URlRor0K4Htlf8SODQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-08T02:08:54.068587Z","bundle_sha256":"df9cba215e7441b9dd27b38f661573ddecd1e4799b10531411704698d0bb97eb"}}