{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:BJB7B3ARL5YUHRBQW37TJ4ZMNC","short_pith_number":"pith:BJB7B3AR","canonical_record":{"source":{"id":"1808.04516","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-08-14T03:40:24Z","cross_cats_sorted":[],"title_canon_sha256":"ad67fa7007888fb2666adada109694ac9ecfbefcfbdd27703bdd8ea44cee5ca3","abstract_canon_sha256":"8835b95ed9b2ff6a7ab396168a093235b2dce99cf755f6502756fbcaa1d5da7a"},"schema_version":"1.0"},"canonical_sha256":"0a43f0ec115f7143c430b6ff34f32c6881beead6308aa23d37b5d822df0979a6","source":{"kind":"arxiv","id":"1808.04516","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1808.04516","created_at":"2026-05-17T23:53:29Z"},{"alias_kind":"arxiv_version","alias_value":"1808.04516v1","created_at":"2026-05-17T23:53:29Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1808.04516","created_at":"2026-05-17T23:53:29Z"},{"alias_kind":"pith_short_12","alias_value":"BJB7B3ARL5YU","created_at":"2026-05-18T12:32:16Z"},{"alias_kind":"pith_short_16","alias_value":"BJB7B3ARL5YUHRBQ","created_at":"2026-05-18T12:32:16Z"},{"alias_kind":"pith_short_8","alias_value":"BJB7B3AR","created_at":"2026-05-18T12:32:16Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:BJB7B3ARL5YUHRBQW37TJ4ZMNC","target":"record","payload":{"canonical_record":{"source":{"id":"1808.04516","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-08-14T03:40:24Z","cross_cats_sorted":[],"title_canon_sha256":"ad67fa7007888fb2666adada109694ac9ecfbefcfbdd27703bdd8ea44cee5ca3","abstract_canon_sha256":"8835b95ed9b2ff6a7ab396168a093235b2dce99cf755f6502756fbcaa1d5da7a"},"schema_version":"1.0"},"canonical_sha256":"0a43f0ec115f7143c430b6ff34f32c6881beead6308aa23d37b5d822df0979a6","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:53:29.415695Z","signature_b64":"gthAqEFEqOZ7cjVqDlH8pG15zj7cdjKtnDMAbeYt+jV8DN0alW3qaKidULDuxJPvIgYgqWv0UYq+FOztoVfMDQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"0a43f0ec115f7143c430b6ff34f32c6881beead6308aa23d37b5d822df0979a6","last_reissued_at":"2026-05-17T23:53:29.415086Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:53:29.415086Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1808.04516","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":"2026-05-17T23:53:29Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"eL2m1GnNnfrgOPHvGib9sNiBaMd5t+7WdwqrtnMga/vp7N4UHeXrqzluB9JycPZoBvktfUVjQ4xM9jR7QjdODw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T19:43:05.191925Z"},"content_sha256":"90dc69cf62cc96be81d3bd44cf332b6c0260b5921081de75c1f1036dbb704d0a","schema_version":"1.0","event_id":"sha256:90dc69cf62cc96be81d3bd44cf332b6c0260b5921081de75c1f1036dbb704d0a"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:BJB7B3ARL5YUHRBQW37TJ4ZMNC","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"In situ measurement of MWA primary beam variation using ORBCOMM","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.IM","authors_text":"(2) ICRAR, (3) Arizona State University, (4) The University of Sydney, 5), (5) Dunlap Institute for Astronomy, (6) University of Wisconsin-Milwaukee, (7) University of Washington, (8) ICRAR, 9, 9), (9) CAASTRO), A. Beardsley (3), Astrophysics, A. Williams (2), B. Crosse (2), B. McKinley (2, B. M. Gaensler (4, C. M. Trott (2, Curtin University, C. Wu (8) ((1) The University of Melbourne, D. Emrich (2), D. Kenney (2), D. L. Kaplan (6), D. Pallot (8), D. Ung (2), J. L. B. Line (1, J. Rasti (1, K. Steele (2), L. Horsley (2), M. Bhardwaj (1, M. F. Morales (7), M. Johnston-Hollitt (2), M. Walker (2), R. B. Wayth (2, R. L. Webster (1, S. J. Tingay (2, T. M. O. Franzen (2), University of Toronto, University of Western Australia","submitted_at":"2018-08-14T03:40:24Z","abstract_excerpt":"We provide the first in situ measurements of antenna element (tile) beam shapes of the Murchison Widefield Array (MWA), a low radio-frequency interferometer and an SKA precursor. Most current MWA processing pipelines use an assumed beam shape, errors in which can cause absolute and relative flux density errors, as well as polarisation 'leakage'. This makes understanding the primary beam of paramount importance, especially for sensitive experiments such as a measurement of the 21 cm line from the epoch of reionisation (EoR). The calibration requirements for measuring the EoR 21 cm line are so e"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1808.04516","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":""},"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":"2026-05-17T23:53:29Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"MYdXAX0PDGdveXKE2cExDZxM5Zaz13yytktcQmep07TN2YvDkAJTDcI9FmSnFlaHhZHovJiUhX2bOdAJl2dxBA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T19:43:05.192586Z"},"content_sha256":"b249db7d615e6abf674cca17e98c8c9dd10d652efdf358185a6278a745985658","schema_version":"1.0","event_id":"sha256:b249db7d615e6abf674cca17e98c8c9dd10d652efdf358185a6278a745985658"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/BJB7B3ARL5YUHRBQW37TJ4ZMNC/bundle.json","state_url":"https://pith.science/pith/BJB7B3ARL5YUHRBQW37TJ4ZMNC/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/BJB7B3ARL5YUHRBQW37TJ4ZMNC/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":"2026-05-28T19:43:05Z","links":{"resolver":"https://pith.science/pith/BJB7B3ARL5YUHRBQW37TJ4ZMNC","bundle":"https://pith.science/pith/BJB7B3ARL5YUHRBQW37TJ4ZMNC/bundle.json","state":"https://pith.science/pith/BJB7B3ARL5YUHRBQW37TJ4ZMNC/state.json","well_known_bundle":"https://pith.science/.well-known/pith/BJB7B3ARL5YUHRBQW37TJ4ZMNC/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:BJB7B3ARL5YUHRBQW37TJ4ZMNC","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":"8835b95ed9b2ff6a7ab396168a093235b2dce99cf755f6502756fbcaa1d5da7a","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-08-14T03:40:24Z","title_canon_sha256":"ad67fa7007888fb2666adada109694ac9ecfbefcfbdd27703bdd8ea44cee5ca3"},"schema_version":"1.0","source":{"id":"1808.04516","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1808.04516","created_at":"2026-05-17T23:53:29Z"},{"alias_kind":"arxiv_version","alias_value":"1808.04516v1","created_at":"2026-05-17T23:53:29Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1808.04516","created_at":"2026-05-17T23:53:29Z"},{"alias_kind":"pith_short_12","alias_value":"BJB7B3ARL5YU","created_at":"2026-05-18T12:32:16Z"},{"alias_kind":"pith_short_16","alias_value":"BJB7B3ARL5YUHRBQ","created_at":"2026-05-18T12:32:16Z"},{"alias_kind":"pith_short_8","alias_value":"BJB7B3AR","created_at":"2026-05-18T12:32:16Z"}],"graph_snapshots":[{"event_id":"sha256:b249db7d615e6abf674cca17e98c8c9dd10d652efdf358185a6278a745985658","target":"graph","created_at":"2026-05-17T23:53:29Z","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"},"paper":{"abstract_excerpt":"We provide the first in situ measurements of antenna element (tile) beam shapes of the Murchison Widefield Array (MWA), a low radio-frequency interferometer and an SKA precursor. Most current MWA processing pipelines use an assumed beam shape, errors in which can cause absolute and relative flux density errors, as well as polarisation 'leakage'. This makes understanding the primary beam of paramount importance, especially for sensitive experiments such as a measurement of the 21 cm line from the epoch of reionisation (EoR). The calibration requirements for measuring the EoR 21 cm line are so e","authors_text":"(2) ICRAR, (3) Arizona State University, (4) The University of Sydney, 5), (5) Dunlap Institute for Astronomy, (6) University of Wisconsin-Milwaukee, (7) University of Washington, (8) ICRAR, 9, 9), (9) CAASTRO), A. Beardsley (3), Astrophysics, A. Williams (2), B. Crosse (2), B. McKinley (2, B. M. Gaensler (4, C. M. Trott (2, Curtin University, C. Wu (8) ((1) The University of Melbourne, D. Emrich (2), D. Kenney (2), D. L. Kaplan (6), D. Pallot (8), D. Ung (2), J. L. B. Line (1, J. Rasti (1, K. Steele (2), L. Horsley (2), M. Bhardwaj (1, M. F. Morales (7), M. Johnston-Hollitt (2), M. Walker (2), R. B. Wayth (2, R. L. Webster (1, S. J. Tingay (2, T. M. O. Franzen (2), University of Toronto, University of Western Australia","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-08-14T03:40:24Z","title":"In situ measurement of MWA primary beam variation using ORBCOMM"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1808.04516","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":"sha256:90dc69cf62cc96be81d3bd44cf332b6c0260b5921081de75c1f1036dbb704d0a","target":"record","created_at":"2026-05-17T23:53:29Z","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":"8835b95ed9b2ff6a7ab396168a093235b2dce99cf755f6502756fbcaa1d5da7a","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2018-08-14T03:40:24Z","title_canon_sha256":"ad67fa7007888fb2666adada109694ac9ecfbefcfbdd27703bdd8ea44cee5ca3"},"schema_version":"1.0","source":{"id":"1808.04516","kind":"arxiv","version":1}},"canonical_sha256":"0a43f0ec115f7143c430b6ff34f32c6881beead6308aa23d37b5d822df0979a6","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"0a43f0ec115f7143c430b6ff34f32c6881beead6308aa23d37b5d822df0979a6","first_computed_at":"2026-05-17T23:53:29.415086Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:53:29.415086Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"gthAqEFEqOZ7cjVqDlH8pG15zj7cdjKtnDMAbeYt+jV8DN0alW3qaKidULDuxJPvIgYgqWv0UYq+FOztoVfMDQ==","signature_status":"signed_v1","signed_at":"2026-05-17T23:53:29.415695Z","signed_message":"canonical_sha256_bytes"},"source_id":"1808.04516","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:90dc69cf62cc96be81d3bd44cf332b6c0260b5921081de75c1f1036dbb704d0a","sha256:b249db7d615e6abf674cca17e98c8c9dd10d652efdf358185a6278a745985658"],"state_sha256":"dd97b9edeb69b28052f03862d7671a9457d15115bbd04f0f8bd7392a1889e9e6"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"QXz+rwfOlfusks5KFhOUqJw8AQ6pDYa7nmfeL1FLXe6lgsB81hCAQKyQJ5G1Ouzb7BrsNdkNCT7RNcpLlIW/CQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-28T19:43:05.195376Z","bundle_sha256":"cfcfeb9179337203bbfb6278cc26888a2c82fe57b4a3707405ebc22f24616317"}}