{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2017:SXAE7EU2B7QX356AKB4COTTCWJ","short_pith_number":"pith:SXAE7EU2","canonical_record":{"source":{"id":"1711.11367","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2017-11-30T13:12:14Z","cross_cats_sorted":["astro-ph.CO","astro-ph.GA"],"title_canon_sha256":"694547d0c21a27f6f09fcce28f75e2f27bec60cfa0d83d03e6200bb9a94a7543","abstract_canon_sha256":"8fa7bd7c65ab400b8eef6578d13cad92a6a665f6c82ade84b3eddc57535b55bd"},"schema_version":"1.0"},"canonical_sha256":"95c04f929a0fe17df7c05078274e62b2786b6c69c138f33b2452458d2ca26814","source":{"kind":"arxiv","id":"1711.11367","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1711.11367","created_at":"2026-05-18T00:26:23Z"},{"alias_kind":"arxiv_version","alias_value":"1711.11367v2","created_at":"2026-05-18T00:26:23Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1711.11367","created_at":"2026-05-18T00:26:23Z"},{"alias_kind":"pith_short_12","alias_value":"SXAE7EU2B7QX","created_at":"2026-05-18T12:31:43Z"},{"alias_kind":"pith_short_16","alias_value":"SXAE7EU2B7QX356A","created_at":"2026-05-18T12:31:43Z"},{"alias_kind":"pith_short_8","alias_value":"SXAE7EU2","created_at":"2026-05-18T12:31:43Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2017:SXAE7EU2B7QX356AKB4COTTCWJ","target":"record","payload":{"canonical_record":{"source":{"id":"1711.11367","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2017-11-30T13:12:14Z","cross_cats_sorted":["astro-ph.CO","astro-ph.GA"],"title_canon_sha256":"694547d0c21a27f6f09fcce28f75e2f27bec60cfa0d83d03e6200bb9a94a7543","abstract_canon_sha256":"8fa7bd7c65ab400b8eef6578d13cad92a6a665f6c82ade84b3eddc57535b55bd"},"schema_version":"1.0"},"canonical_sha256":"95c04f929a0fe17df7c05078274e62b2786b6c69c138f33b2452458d2ca26814","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:26:23.499110Z","signature_b64":"5XgoMRMjmZHdHFpQDix+4veuo8J6gv6i3nWnL7TX31hpFEYIB3rdoChPaAkDqfnHEWbA+WPwBVwQYpUFd8+LBA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"95c04f929a0fe17df7c05078274e62b2786b6c69c138f33b2452458d2ca26814","last_reissued_at":"2026-05-18T00:26:23.498648Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:26:23.498648Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1711.11367","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":"2026-05-18T00:26:23Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"U8t7cBRXU1kL1ItMTT8mMjBMGqzhbncgSeMoEMbv017OSdEJTLb9IFZ14OYgN8uJ7JR66Rs2575pOti4LvBOBA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-02T20:55:40.015683Z"},"content_sha256":"50cfdfe8903c51ff8f0194a7e4df854e0e1b627923a0580ca0b3a5f8b7f2891d","schema_version":"1.0","event_id":"sha256:50cfdfe8903c51ff8f0194a7e4df854e0e1b627923a0580ca0b3a5f8b7f2891d"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2017:SXAE7EU2B7QX356AKB4COTTCWJ","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"A radio spectral index map and catalogue at 147-1400 MHz covering 80 per cent of the sky","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.CO","astro-ph.GA"],"primary_cat":"astro-ph.IM","authors_text":"D. A. Frail, F. De Gasperin, H. T. Intema","submitted_at":"2017-11-30T13:12:14Z","abstract_excerpt":"The radio spectral index is a powerful probe for classifying cosmic radio sources and understanding the origin of the radio emission. Combining data at 147 MHz and 1.4 GHz from the TIFR GMRT Sky Survey (TGSS) and the NRAO VLA Sky Survey (NVSS), we produced a large-area radio spectral index map of ~80 per cent of the sky (Dec > -40 deg), as well as a radio spectral index catalogue containing 1,396,515 sources, of which 503,647 are not upper or lower limits. Almost every TGSS source has a detected counterpart, while this is true only for 36 per cent of NVSS sources. We released both the map and "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1711.11367","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":"2026-05-18T00:26:23Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ECnR4ypI86XqvMYRyb61oEtexLGSj2Rh15/lqDL3KqSWu4hOc+GRuhNKWl20WHuHSCPoaoEyajSCx1ka+6eSAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-02T20:55:40.016026Z"},"content_sha256":"67332a78ebe4f3e1522a11e49c618b5f05b44929677a0c2e1cfdf847261c7882","schema_version":"1.0","event_id":"sha256:67332a78ebe4f3e1522a11e49c618b5f05b44929677a0c2e1cfdf847261c7882"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/SXAE7EU2B7QX356AKB4COTTCWJ/bundle.json","state_url":"https://pith.science/pith/SXAE7EU2B7QX356AKB4COTTCWJ/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/SXAE7EU2B7QX356AKB4COTTCWJ/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":"2026-06-02T20:55:40Z","links":{"resolver":"https://pith.science/pith/SXAE7EU2B7QX356AKB4COTTCWJ","bundle":"https://pith.science/pith/SXAE7EU2B7QX356AKB4COTTCWJ/bundle.json","state":"https://pith.science/pith/SXAE7EU2B7QX356AKB4COTTCWJ/state.json","well_known_bundle":"https://pith.science/.well-known/pith/SXAE7EU2B7QX356AKB4COTTCWJ/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2017:SXAE7EU2B7QX356AKB4COTTCWJ","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":"8fa7bd7c65ab400b8eef6578d13cad92a6a665f6c82ade84b3eddc57535b55bd","cross_cats_sorted":["astro-ph.CO","astro-ph.GA"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2017-11-30T13:12:14Z","title_canon_sha256":"694547d0c21a27f6f09fcce28f75e2f27bec60cfa0d83d03e6200bb9a94a7543"},"schema_version":"1.0","source":{"id":"1711.11367","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1711.11367","created_at":"2026-05-18T00:26:23Z"},{"alias_kind":"arxiv_version","alias_value":"1711.11367v2","created_at":"2026-05-18T00:26:23Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1711.11367","created_at":"2026-05-18T00:26:23Z"},{"alias_kind":"pith_short_12","alias_value":"SXAE7EU2B7QX","created_at":"2026-05-18T12:31:43Z"},{"alias_kind":"pith_short_16","alias_value":"SXAE7EU2B7QX356A","created_at":"2026-05-18T12:31:43Z"},{"alias_kind":"pith_short_8","alias_value":"SXAE7EU2","created_at":"2026-05-18T12:31:43Z"}],"graph_snapshots":[{"event_id":"sha256:67332a78ebe4f3e1522a11e49c618b5f05b44929677a0c2e1cfdf847261c7882","target":"graph","created_at":"2026-05-18T00:26:23Z","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":"The radio spectral index is a powerful probe for classifying cosmic radio sources and understanding the origin of the radio emission. Combining data at 147 MHz and 1.4 GHz from the TIFR GMRT Sky Survey (TGSS) and the NRAO VLA Sky Survey (NVSS), we produced a large-area radio spectral index map of ~80 per cent of the sky (Dec > -40 deg), as well as a radio spectral index catalogue containing 1,396,515 sources, of which 503,647 are not upper or lower limits. Almost every TGSS source has a detected counterpart, while this is true only for 36 per cent of NVSS sources. We released both the map and ","authors_text":"D. A. Frail, F. De Gasperin, H. T. Intema","cross_cats":["astro-ph.CO","astro-ph.GA"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2017-11-30T13:12:14Z","title":"A radio spectral index map and catalogue at 147-1400 MHz covering 80 per cent of the sky"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1711.11367","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":"sha256:50cfdfe8903c51ff8f0194a7e4df854e0e1b627923a0580ca0b3a5f8b7f2891d","target":"record","created_at":"2026-05-18T00:26:23Z","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":"8fa7bd7c65ab400b8eef6578d13cad92a6a665f6c82ade84b3eddc57535b55bd","cross_cats_sorted":["astro-ph.CO","astro-ph.GA"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2017-11-30T13:12:14Z","title_canon_sha256":"694547d0c21a27f6f09fcce28f75e2f27bec60cfa0d83d03e6200bb9a94a7543"},"schema_version":"1.0","source":{"id":"1711.11367","kind":"arxiv","version":2}},"canonical_sha256":"95c04f929a0fe17df7c05078274e62b2786b6c69c138f33b2452458d2ca26814","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"95c04f929a0fe17df7c05078274e62b2786b6c69c138f33b2452458d2ca26814","first_computed_at":"2026-05-18T00:26:23.498648Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:26:23.498648Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"5XgoMRMjmZHdHFpQDix+4veuo8J6gv6i3nWnL7TX31hpFEYIB3rdoChPaAkDqfnHEWbA+WPwBVwQYpUFd8+LBA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:26:23.499110Z","signed_message":"canonical_sha256_bytes"},"source_id":"1711.11367","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:50cfdfe8903c51ff8f0194a7e4df854e0e1b627923a0580ca0b3a5f8b7f2891d","sha256:67332a78ebe4f3e1522a11e49c618b5f05b44929677a0c2e1cfdf847261c7882"],"state_sha256":"f125423befc75dfdde7f34144757d8e7de6aaf0db3c4e9dc9dd71cd6ee0d39ea"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"bC7TmPQNx/qLxhOO2NOF05xLs7dQn70g4TWi8Bhy7OBG4jslLLNKf9h1o6PcpKtBTBeDJY9azQ5eKcMr0oJuDQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-02T20:55:40.018005Z","bundle_sha256":"9cf523b7ae1690a5915a5c2269fad9157a654cda555b5fc918a28b086fb289d7"}}