{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2013:7DVJTU2N56ZOKYL5JWUPVD5HYI","short_pith_number":"pith:7DVJTU2N","canonical_record":{"source":{"id":"1307.6759","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2013-07-25T14:42:07Z","cross_cats_sorted":["astro-ph.CO","astro-ph.HE"],"title_canon_sha256":"3298f2a6eb8b9eb87a26b1530736fa140635d5b10b4b84fcb527051667ac6302","abstract_canon_sha256":"2d48f800926db2c460f14b5e9beb17005ed8ed3507746dd3fe507d9a39d03bb6"},"schema_version":"1.0"},"canonical_sha256":"f8ea99d34defb2e5617d4da8fa8fa7c20340b54f44ce6e8ded5f37553f0fbed4","source":{"kind":"arxiv","id":"1307.6759","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1307.6759","created_at":"2026-05-18T03:17:34Z"},{"alias_kind":"arxiv_version","alias_value":"1307.6759v1","created_at":"2026-05-18T03:17:34Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1307.6759","created_at":"2026-05-18T03:17:34Z"},{"alias_kind":"pith_short_12","alias_value":"7DVJTU2N56ZO","created_at":"2026-05-18T12:27:36Z"},{"alias_kind":"pith_short_16","alias_value":"7DVJTU2N56ZOKYL5","created_at":"2026-05-18T12:27:36Z"},{"alias_kind":"pith_short_8","alias_value":"7DVJTU2N","created_at":"2026-05-18T12:27:36Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2013:7DVJTU2N56ZOKYL5JWUPVD5HYI","target":"record","payload":{"canonical_record":{"source":{"id":"1307.6759","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2013-07-25T14:42:07Z","cross_cats_sorted":["astro-ph.CO","astro-ph.HE"],"title_canon_sha256":"3298f2a6eb8b9eb87a26b1530736fa140635d5b10b4b84fcb527051667ac6302","abstract_canon_sha256":"2d48f800926db2c460f14b5e9beb17005ed8ed3507746dd3fe507d9a39d03bb6"},"schema_version":"1.0"},"canonical_sha256":"f8ea99d34defb2e5617d4da8fa8fa7c20340b54f44ce6e8ded5f37553f0fbed4","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T03:17:34.749858Z","signature_b64":"2G8awE+jSUAR8A07Uvfz7RoeKtWHsVhR+fewlzitQCsppykgelMtsZPeQE66cfgbIfOn3MMG16+YYFaPXnJaDw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"f8ea99d34defb2e5617d4da8fa8fa7c20340b54f44ce6e8ded5f37553f0fbed4","last_reissued_at":"2026-05-18T03:17:34.749253Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T03:17:34.749253Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1307.6759","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":"2026-05-18T03:17:34Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Dwd07tiiDqr/5GsUx6RpZRRkNjsp05E95vpK+NgORXglOZOcgsdSLo/pvkhzvC+6ukfby+jEwGMk7MsC0sb5Bg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-10T23:42:45.284302Z"},"content_sha256":"f76ad54b8de62ab18c21611c2af0c97f33dee92b30265e992ed646f37568e4f5","schema_version":"1.0","event_id":"sha256:f76ad54b8de62ab18c21611c2af0c97f33dee92b30265e992ed646f37568e4f5"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2013:7DVJTU2N56ZOKYL5JWUPVD5HYI","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Describing the Uncertainties in VLBI Images","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.CO","astro-ph.HE"],"primary_cat":"astro-ph.GA","authors_text":"Colm P. Coughlan, Denise C. Gabuzda","submitted_at":"2013-07-25T14:42:07Z","abstract_excerpt":"We are investigating a new approach to modelling uncertainties in individual pixels of Very Long Baseline Interferometry (VLBI) intensity (Stokes I, Q, U) images. Comparison of distributions of our calculated uncertainties for model sources with the results of Monte Carlo simulations shows that our method correctly reproduces the overall level and pattern of uncertainties in intensity images for model sources that are not too compact. Refinement of the approach to better reproduce uncertainties in compact sources is being studied. This new approach should ultimately provide a means to correctl"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1307.6759","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":"2026-05-18T03:17:34Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Enc6uMlQkrvXEX6fbbDhpm75/92zLpawY/GFRH+LsiM9hzPavayzNxJr2PFwuQGbIdOm2r2Steft2wkTZPlvBA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-10T23:42:45.284696Z"},"content_sha256":"794ac79752e182e210fa14a805ec25f8d4719819530e9f688f0e4ed281d80dab","schema_version":"1.0","event_id":"sha256:794ac79752e182e210fa14a805ec25f8d4719819530e9f688f0e4ed281d80dab"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/7DVJTU2N56ZOKYL5JWUPVD5HYI/bundle.json","state_url":"https://pith.science/pith/7DVJTU2N56ZOKYL5JWUPVD5HYI/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/7DVJTU2N56ZOKYL5JWUPVD5HYI/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":"2026-06-10T23:42:45Z","links":{"resolver":"https://pith.science/pith/7DVJTU2N56ZOKYL5JWUPVD5HYI","bundle":"https://pith.science/pith/7DVJTU2N56ZOKYL5JWUPVD5HYI/bundle.json","state":"https://pith.science/pith/7DVJTU2N56ZOKYL5JWUPVD5HYI/state.json","well_known_bundle":"https://pith.science/.well-known/pith/7DVJTU2N56ZOKYL5JWUPVD5HYI/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2013:7DVJTU2N56ZOKYL5JWUPVD5HYI","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":"2d48f800926db2c460f14b5e9beb17005ed8ed3507746dd3fe507d9a39d03bb6","cross_cats_sorted":["astro-ph.CO","astro-ph.HE"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2013-07-25T14:42:07Z","title_canon_sha256":"3298f2a6eb8b9eb87a26b1530736fa140635d5b10b4b84fcb527051667ac6302"},"schema_version":"1.0","source":{"id":"1307.6759","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1307.6759","created_at":"2026-05-18T03:17:34Z"},{"alias_kind":"arxiv_version","alias_value":"1307.6759v1","created_at":"2026-05-18T03:17:34Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1307.6759","created_at":"2026-05-18T03:17:34Z"},{"alias_kind":"pith_short_12","alias_value":"7DVJTU2N56ZO","created_at":"2026-05-18T12:27:36Z"},{"alias_kind":"pith_short_16","alias_value":"7DVJTU2N56ZOKYL5","created_at":"2026-05-18T12:27:36Z"},{"alias_kind":"pith_short_8","alias_value":"7DVJTU2N","created_at":"2026-05-18T12:27:36Z"}],"graph_snapshots":[{"event_id":"sha256:794ac79752e182e210fa14a805ec25f8d4719819530e9f688f0e4ed281d80dab","target":"graph","created_at":"2026-05-18T03:17:34Z","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 are investigating a new approach to modelling uncertainties in individual pixels of Very Long Baseline Interferometry (VLBI) intensity (Stokes I, Q, U) images. Comparison of distributions of our calculated uncertainties for model sources with the results of Monte Carlo simulations shows that our method correctly reproduces the overall level and pattern of uncertainties in intensity images for model sources that are not too compact. Refinement of the approach to better reproduce uncertainties in compact sources is being studied. This new approach should ultimately provide a means to correctl","authors_text":"Colm P. Coughlan, Denise C. Gabuzda","cross_cats":["astro-ph.CO","astro-ph.HE"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2013-07-25T14:42:07Z","title":"Describing the Uncertainties in VLBI Images"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1307.6759","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:f76ad54b8de62ab18c21611c2af0c97f33dee92b30265e992ed646f37568e4f5","target":"record","created_at":"2026-05-18T03:17:34Z","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":"2d48f800926db2c460f14b5e9beb17005ed8ed3507746dd3fe507d9a39d03bb6","cross_cats_sorted":["astro-ph.CO","astro-ph.HE"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2013-07-25T14:42:07Z","title_canon_sha256":"3298f2a6eb8b9eb87a26b1530736fa140635d5b10b4b84fcb527051667ac6302"},"schema_version":"1.0","source":{"id":"1307.6759","kind":"arxiv","version":1}},"canonical_sha256":"f8ea99d34defb2e5617d4da8fa8fa7c20340b54f44ce6e8ded5f37553f0fbed4","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"f8ea99d34defb2e5617d4da8fa8fa7c20340b54f44ce6e8ded5f37553f0fbed4","first_computed_at":"2026-05-18T03:17:34.749253Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T03:17:34.749253Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"2G8awE+jSUAR8A07Uvfz7RoeKtWHsVhR+fewlzitQCsppykgelMtsZPeQE66cfgbIfOn3MMG16+YYFaPXnJaDw==","signature_status":"signed_v1","signed_at":"2026-05-18T03:17:34.749858Z","signed_message":"canonical_sha256_bytes"},"source_id":"1307.6759","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:f76ad54b8de62ab18c21611c2af0c97f33dee92b30265e992ed646f37568e4f5","sha256:794ac79752e182e210fa14a805ec25f8d4719819530e9f688f0e4ed281d80dab"],"state_sha256":"5619b739ba6ab7b8f6dd2db2c5cb7d17eae42dd9cfca9e318741eb52f2032c6e"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"hCi+okgETvzPKVij3L0SobkmMosPj8rS9j+c4vqMdyDNs4QoxuN1r6iSK+zjqgsBsoDawk/l5n+TsWfGJqb3Dg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-10T23:42:45.286991Z","bundle_sha256":"0d145d41272c1c5f6404162ff0ae27d1694fdfe1fcb746e60b5d8661be3148c4"}}