{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2013:EHAYTZ7FQU34OUYLOLFRQ7P7J7","short_pith_number":"pith:EHAYTZ7F","canonical_record":{"source":{"id":"1309.4646","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2013-09-18T13:56:43Z","cross_cats_sorted":[],"title_canon_sha256":"3c3e9fbcb3593222584bb6ed149f95862fae6e7e9839c09b387c57ecbd681f44","abstract_canon_sha256":"06f286f7ad98cb039761a74d823803b23136d69be0013f7c336291eb7c6aeb31"},"schema_version":"1.0"},"canonical_sha256":"21c189e7e58537c7530b72cb187dff4ff2643cca8ef91a6f2a6e8a6148f06b08","source":{"kind":"arxiv","id":"1309.4646","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1309.4646","created_at":"2026-05-18T03:12:58Z"},{"alias_kind":"arxiv_version","alias_value":"1309.4646v1","created_at":"2026-05-18T03:12:58Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1309.4646","created_at":"2026-05-18T03:12:58Z"},{"alias_kind":"pith_short_12","alias_value":"EHAYTZ7FQU34","created_at":"2026-05-18T12:27:43Z"},{"alias_kind":"pith_short_16","alias_value":"EHAYTZ7FQU34OUYL","created_at":"2026-05-18T12:27:43Z"},{"alias_kind":"pith_short_8","alias_value":"EHAYTZ7F","created_at":"2026-05-18T12:27:43Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2013:EHAYTZ7FQU34OUYLOLFRQ7P7J7","target":"record","payload":{"canonical_record":{"source":{"id":"1309.4646","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2013-09-18T13:56:43Z","cross_cats_sorted":[],"title_canon_sha256":"3c3e9fbcb3593222584bb6ed149f95862fae6e7e9839c09b387c57ecbd681f44","abstract_canon_sha256":"06f286f7ad98cb039761a74d823803b23136d69be0013f7c336291eb7c6aeb31"},"schema_version":"1.0"},"canonical_sha256":"21c189e7e58537c7530b72cb187dff4ff2643cca8ef91a6f2a6e8a6148f06b08","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T03:12:58.693540Z","signature_b64":"ekhnm3MKB8n3NEY443Liaxp/kJPPBgHu/T25Lyg1bpORbmFVISmxvaGbBRROmi6nuE3IH6UuNZz5oTfK1GYeAg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"21c189e7e58537c7530b72cb187dff4ff2643cca8ef91a6f2a6e8a6148f06b08","last_reissued_at":"2026-05-18T03:12:58.692850Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T03:12:58.692850Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1309.4646","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":"2026-05-18T03:12:58Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"JWP2ql0X+9zZgfwOExv/fHBeVkdelX1WeeYAKo2GD9qWSePtL8+VSvfiR0pQ1eOHy8rf4wM0MR9X6XnU6z1SDA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T19:54:35.226625Z"},"content_sha256":"4515dbe1f36aec4051fb02c8623480161cea8ee14b2e3cd8b5dead0ef4adc314","schema_version":"1.0","event_id":"sha256:4515dbe1f36aec4051fb02c8623480161cea8ee14b2e3cd8b5dead0ef4adc314"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2013:EHAYTZ7FQU34OUYLOLFRQ7P7J7","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Probing Magnetic Fields using the Giant Metrewave Radio Telescope","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.IM","authors_text":"D. A. Green, J. S. Farnes, N. G. Kantharia","submitted_at":"2013-09-18T13:56:43Z","abstract_excerpt":"We present the first spectropolarimetric radio observations that apply Rotation Measure (RM) Synthesis to interferometric data from the Giant Metrewave Radio Telescope (GMRT) at 610 MHz. Spectropolarimetry requires measurement of a large number of instrumental systematics so that their effects can be calibrated - a technical problem that is currently being faced by the upcoming SKA pathfinders. Our fully-calibrated data allow for the peak Faraday depth and polarisation fraction to be measured for sub-mJy compact sources in the field of M51 at 610 MHz. The diffuse extended emission in the inter"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1309.4646","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":"2026-05-18T03:12:58Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"rAMMITE+r4nxwla3RdzS85lTsnazUa1jPmtceIdvihGPLW+hAaULjtCrurviz8mnQHuJ6rp2hMLh0ldAEWpfDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T19:54:35.227291Z"},"content_sha256":"c3efc76088a8f3e653f984803ae4f42394a5c63027b716596fdf0173594a8440","schema_version":"1.0","event_id":"sha256:c3efc76088a8f3e653f984803ae4f42394a5c63027b716596fdf0173594a8440"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/EHAYTZ7FQU34OUYLOLFRQ7P7J7/bundle.json","state_url":"https://pith.science/pith/EHAYTZ7FQU34OUYLOLFRQ7P7J7/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/EHAYTZ7FQU34OUYLOLFRQ7P7J7/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":"2026-05-25T19:54:35Z","links":{"resolver":"https://pith.science/pith/EHAYTZ7FQU34OUYLOLFRQ7P7J7","bundle":"https://pith.science/pith/EHAYTZ7FQU34OUYLOLFRQ7P7J7/bundle.json","state":"https://pith.science/pith/EHAYTZ7FQU34OUYLOLFRQ7P7J7/state.json","well_known_bundle":"https://pith.science/.well-known/pith/EHAYTZ7FQU34OUYLOLFRQ7P7J7/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2013:EHAYTZ7FQU34OUYLOLFRQ7P7J7","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":"06f286f7ad98cb039761a74d823803b23136d69be0013f7c336291eb7c6aeb31","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2013-09-18T13:56:43Z","title_canon_sha256":"3c3e9fbcb3593222584bb6ed149f95862fae6e7e9839c09b387c57ecbd681f44"},"schema_version":"1.0","source":{"id":"1309.4646","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1309.4646","created_at":"2026-05-18T03:12:58Z"},{"alias_kind":"arxiv_version","alias_value":"1309.4646v1","created_at":"2026-05-18T03:12:58Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1309.4646","created_at":"2026-05-18T03:12:58Z"},{"alias_kind":"pith_short_12","alias_value":"EHAYTZ7FQU34","created_at":"2026-05-18T12:27:43Z"},{"alias_kind":"pith_short_16","alias_value":"EHAYTZ7FQU34OUYL","created_at":"2026-05-18T12:27:43Z"},{"alias_kind":"pith_short_8","alias_value":"EHAYTZ7F","created_at":"2026-05-18T12:27:43Z"}],"graph_snapshots":[{"event_id":"sha256:c3efc76088a8f3e653f984803ae4f42394a5c63027b716596fdf0173594a8440","target":"graph","created_at":"2026-05-18T03:12:58Z","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 present the first spectropolarimetric radio observations that apply Rotation Measure (RM) Synthesis to interferometric data from the Giant Metrewave Radio Telescope (GMRT) at 610 MHz. Spectropolarimetry requires measurement of a large number of instrumental systematics so that their effects can be calibrated - a technical problem that is currently being faced by the upcoming SKA pathfinders. Our fully-calibrated data allow for the peak Faraday depth and polarisation fraction to be measured for sub-mJy compact sources in the field of M51 at 610 MHz. The diffuse extended emission in the inter","authors_text":"D. A. Green, J. S. Farnes, N. G. Kantharia","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2013-09-18T13:56:43Z","title":"Probing Magnetic Fields using the Giant Metrewave Radio Telescope"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1309.4646","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":"sha256:4515dbe1f36aec4051fb02c8623480161cea8ee14b2e3cd8b5dead0ef4adc314","target":"record","created_at":"2026-05-18T03:12:58Z","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":"06f286f7ad98cb039761a74d823803b23136d69be0013f7c336291eb7c6aeb31","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2013-09-18T13:56:43Z","title_canon_sha256":"3c3e9fbcb3593222584bb6ed149f95862fae6e7e9839c09b387c57ecbd681f44"},"schema_version":"1.0","source":{"id":"1309.4646","kind":"arxiv","version":1}},"canonical_sha256":"21c189e7e58537c7530b72cb187dff4ff2643cca8ef91a6f2a6e8a6148f06b08","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"21c189e7e58537c7530b72cb187dff4ff2643cca8ef91a6f2a6e8a6148f06b08","first_computed_at":"2026-05-18T03:12:58.692850Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T03:12:58.692850Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"ekhnm3MKB8n3NEY443Liaxp/kJPPBgHu/T25Lyg1bpORbmFVISmxvaGbBRROmi6nuE3IH6UuNZz5oTfK1GYeAg==","signature_status":"signed_v1","signed_at":"2026-05-18T03:12:58.693540Z","signed_message":"canonical_sha256_bytes"},"source_id":"1309.4646","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:4515dbe1f36aec4051fb02c8623480161cea8ee14b2e3cd8b5dead0ef4adc314","sha256:c3efc76088a8f3e653f984803ae4f42394a5c63027b716596fdf0173594a8440"],"state_sha256":"05bbeb181bb10803289f8b269bd3ecbe7729de8f788f6738739173459020ce51"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"fDPEjQg1RsnXQIikcAJTm+W7w3OHAs6NKwGbyU1HVa8+0mUlbT67jhgNXMRKDYxc686ukmjw/QHh48pwuH5JDw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-25T19:54:35.230852Z","bundle_sha256":"47c7f15d95ce66a1e8e4a85118c58427df12be16f41d940b8d94ab69b0f10486"}}