{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:5UUHBKULAKI4FJA3DJ6QXKPPFI","short_pith_number":"pith:5UUHBKUL","canonical_record":{"source":{"id":"1805.01900","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-05-04T18:00:01Z","cross_cats_sorted":[],"title_canon_sha256":"ab15bf5e5f087c162ff0a30458e1fcc3720c651ee365403ab588e18628601eb9","abstract_canon_sha256":"6d0950e68ad6cae6e032a43db1e4fffcf45fdfcd1a113d89b79aad7e409af664"},"schema_version":"1.0"},"canonical_sha256":"ed2870aa8b0291c2a41b1a7d0ba9ef2a28b1ddde045d03eaac1006f801eb35e9","source":{"kind":"arxiv","id":"1805.01900","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1805.01900","created_at":"2026-05-18T00:15:54Z"},{"alias_kind":"arxiv_version","alias_value":"1805.01900v1","created_at":"2026-05-18T00:15:54Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1805.01900","created_at":"2026-05-18T00:15:54Z"},{"alias_kind":"pith_short_12","alias_value":"5UUHBKULAKI4","created_at":"2026-05-18T12:32:08Z"},{"alias_kind":"pith_short_16","alias_value":"5UUHBKULAKI4FJA3","created_at":"2026-05-18T12:32:08Z"},{"alias_kind":"pith_short_8","alias_value":"5UUHBKUL","created_at":"2026-05-18T12:32:08Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:5UUHBKULAKI4FJA3DJ6QXKPPFI","target":"record","payload":{"canonical_record":{"source":{"id":"1805.01900","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-05-04T18:00:01Z","cross_cats_sorted":[],"title_canon_sha256":"ab15bf5e5f087c162ff0a30458e1fcc3720c651ee365403ab588e18628601eb9","abstract_canon_sha256":"6d0950e68ad6cae6e032a43db1e4fffcf45fdfcd1a113d89b79aad7e409af664"},"schema_version":"1.0"},"canonical_sha256":"ed2870aa8b0291c2a41b1a7d0ba9ef2a28b1ddde045d03eaac1006f801eb35e9","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:15:54.179993Z","signature_b64":"OBHuLcr6SN9xbXnRRcIfPFV50ppHxkmS7j4LdzfJgKYLEg6Hu9rJEzHGWjDVffIg0925VvMkSNI1muMt0wf3Cg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"ed2870aa8b0291c2a41b1a7d0ba9ef2a28b1ddde045d03eaac1006f801eb35e9","last_reissued_at":"2026-05-18T00:15:54.179172Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:15:54.179172Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1805.01900","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":"2026-05-18T00:15:54Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"6sAaudqbh+/AKuhq8cxzs7ZX44dpi79LTx1QTTCUEXnm+OV+EAy8rB/e4iestfXFqnk5aaZ7HmjIW0Qre+54DQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-07T07:26:12.356609Z"},"content_sha256":"27b21709718d3f638f3a83d48c75bd6854c0d7fd9dd914b811d5ff69e5641b69","schema_version":"1.0","event_id":"sha256:27b21709718d3f638f3a83d48c75bd6854c0d7fd9dd914b811d5ff69e5641b69"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:5UUHBKULAKI4FJA3DJ6QXKPPFI","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"First evidence of diffuse ultra-steep-spectrum radio emission surrounding the cool core of a cluster","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Amanda Wilber, Andrea Botteon, Annalisa Bonafede, David Rafferty, Federica Savini, Francesco de Gasperin, Gianfranco Brunetti, Glenn White, Huib Intema, Huub Roettgering, Marcus Brueggen, Matthias Hoeft, Reinout van Weeren, Rossella Cassano, Simona Giacintucci, Timothy Shimwell, Virginia Cuciti","submitted_at":"2018-05-04T18:00:01Z","abstract_excerpt":"Diffuse synchrotron radio emission from cosmic-ray electrons is observed at the center of a number of galaxy clusters. These sources can be classified either as giant radio halos, which occur in merging clusters, or as mini halos, which are found only in cool-core clusters. In this paper, we present the first discovery of a cool-core cluster with an associated mini halo that also shows ultra-steep-spectrum emission extending well beyond the core that resembles radio halo emission. The large-scale component is discovered thanks to LOFAR observations at 144 MHz. We also analyse GMRT observations"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1805.01900","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":"2026-05-18T00:15:54Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Dd6ZFIk+8O5pKrhFn7fDNBqz+WX12C2YofsivgFCc8d22SLxdS5KD5W+EhkhNqRSD9vQGiEWrhsb02xteLdBCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-07T07:26:12.357177Z"},"content_sha256":"600c4f8331ec15a56f2dee2e898952210ec06067a20207690dd55cfbc182a628","schema_version":"1.0","event_id":"sha256:600c4f8331ec15a56f2dee2e898952210ec06067a20207690dd55cfbc182a628"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/5UUHBKULAKI4FJA3DJ6QXKPPFI/bundle.json","state_url":"https://pith.science/pith/5UUHBKULAKI4FJA3DJ6QXKPPFI/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/5UUHBKULAKI4FJA3DJ6QXKPPFI/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":"2026-06-07T07:26:12Z","links":{"resolver":"https://pith.science/pith/5UUHBKULAKI4FJA3DJ6QXKPPFI","bundle":"https://pith.science/pith/5UUHBKULAKI4FJA3DJ6QXKPPFI/bundle.json","state":"https://pith.science/pith/5UUHBKULAKI4FJA3DJ6QXKPPFI/state.json","well_known_bundle":"https://pith.science/.well-known/pith/5UUHBKULAKI4FJA3DJ6QXKPPFI/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:5UUHBKULAKI4FJA3DJ6QXKPPFI","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":"6d0950e68ad6cae6e032a43db1e4fffcf45fdfcd1a113d89b79aad7e409af664","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-05-04T18:00:01Z","title_canon_sha256":"ab15bf5e5f087c162ff0a30458e1fcc3720c651ee365403ab588e18628601eb9"},"schema_version":"1.0","source":{"id":"1805.01900","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1805.01900","created_at":"2026-05-18T00:15:54Z"},{"alias_kind":"arxiv_version","alias_value":"1805.01900v1","created_at":"2026-05-18T00:15:54Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1805.01900","created_at":"2026-05-18T00:15:54Z"},{"alias_kind":"pith_short_12","alias_value":"5UUHBKULAKI4","created_at":"2026-05-18T12:32:08Z"},{"alias_kind":"pith_short_16","alias_value":"5UUHBKULAKI4FJA3","created_at":"2026-05-18T12:32:08Z"},{"alias_kind":"pith_short_8","alias_value":"5UUHBKUL","created_at":"2026-05-18T12:32:08Z"}],"graph_snapshots":[{"event_id":"sha256:600c4f8331ec15a56f2dee2e898952210ec06067a20207690dd55cfbc182a628","target":"graph","created_at":"2026-05-18T00:15:54Z","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":"Diffuse synchrotron radio emission from cosmic-ray electrons is observed at the center of a number of galaxy clusters. These sources can be classified either as giant radio halos, which occur in merging clusters, or as mini halos, which are found only in cool-core clusters. In this paper, we present the first discovery of a cool-core cluster with an associated mini halo that also shows ultra-steep-spectrum emission extending well beyond the core that resembles radio halo emission. The large-scale component is discovered thanks to LOFAR observations at 144 MHz. We also analyse GMRT observations","authors_text":"Amanda Wilber, Andrea Botteon, Annalisa Bonafede, David Rafferty, Federica Savini, Francesco de Gasperin, Gianfranco Brunetti, Glenn White, Huib Intema, Huub Roettgering, Marcus Brueggen, Matthias Hoeft, Reinout van Weeren, Rossella Cassano, Simona Giacintucci, Timothy Shimwell, Virginia Cuciti","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-05-04T18:00:01Z","title":"First evidence of diffuse ultra-steep-spectrum radio emission surrounding the cool core of a cluster"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1805.01900","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":"sha256:27b21709718d3f638f3a83d48c75bd6854c0d7fd9dd914b811d5ff69e5641b69","target":"record","created_at":"2026-05-18T00:15:54Z","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":"6d0950e68ad6cae6e032a43db1e4fffcf45fdfcd1a113d89b79aad7e409af664","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-05-04T18:00:01Z","title_canon_sha256":"ab15bf5e5f087c162ff0a30458e1fcc3720c651ee365403ab588e18628601eb9"},"schema_version":"1.0","source":{"id":"1805.01900","kind":"arxiv","version":1}},"canonical_sha256":"ed2870aa8b0291c2a41b1a7d0ba9ef2a28b1ddde045d03eaac1006f801eb35e9","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"ed2870aa8b0291c2a41b1a7d0ba9ef2a28b1ddde045d03eaac1006f801eb35e9","first_computed_at":"2026-05-18T00:15:54.179172Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:15:54.179172Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"OBHuLcr6SN9xbXnRRcIfPFV50ppHxkmS7j4LdzfJgKYLEg6Hu9rJEzHGWjDVffIg0925VvMkSNI1muMt0wf3Cg==","signature_status":"signed_v1","signed_at":"2026-05-18T00:15:54.179993Z","signed_message":"canonical_sha256_bytes"},"source_id":"1805.01900","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:27b21709718d3f638f3a83d48c75bd6854c0d7fd9dd914b811d5ff69e5641b69","sha256:600c4f8331ec15a56f2dee2e898952210ec06067a20207690dd55cfbc182a628"],"state_sha256":"c468d0153acc911e6db7e40a7073b49ecd855f77176dca9b811b2d91d77569c9"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"QnqgMZpsxIorU9kPOf5hMnj64LmxcJaAhdvfEPB7eU/6EPuRpacSjGGrkv+fjQDkGL80cToE+h1OwKHfOPH5DQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-07T07:26:12.360792Z","bundle_sha256":"c9be16a8fcd6c1388a5163edad3678e6611dbbbaffcde1c0bb4a2bdd033ab90a"}}