{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2009:AIJNHVWJMFLFL3AD42HMAXJ5F4","short_pith_number":"pith:AIJNHVWJ","canonical_record":{"source":{"id":"0909.1997","kind":"arxiv","version":3},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2009-09-10T19:44:44Z","cross_cats_sorted":[],"title_canon_sha256":"024a22d8f7688bfed5b562eaae781a01765b7334662f8747ad5c8b6b16488b1e","abstract_canon_sha256":"8f37d44d8af5c205958321f483811ecc69f96fb5eb5bb1de8be54754ee96c3db"},"schema_version":"1.0"},"canonical_sha256":"0212d3d6c9615655ec03e68ec05d3d2f3122db797bf88c88f6d7319ba74e419b","source":{"kind":"arxiv","id":"0909.1997","version":3},"source_aliases":[{"alias_kind":"arxiv","alias_value":"0909.1997","created_at":"2026-05-18T02:24:47Z"},{"alias_kind":"arxiv_version","alias_value":"0909.1997v3","created_at":"2026-05-18T02:24:47Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0909.1997","created_at":"2026-05-18T02:24:47Z"},{"alias_kind":"pith_short_12","alias_value":"AIJNHVWJMFLF","created_at":"2026-05-18T12:25:58Z"},{"alias_kind":"pith_short_16","alias_value":"AIJNHVWJMFLFL3AD","created_at":"2026-05-18T12:25:58Z"},{"alias_kind":"pith_short_8","alias_value":"AIJNHVWJ","created_at":"2026-05-18T12:25:58Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2009:AIJNHVWJMFLFL3AD42HMAXJ5F4","target":"record","payload":{"canonical_record":{"source":{"id":"0909.1997","kind":"arxiv","version":3},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2009-09-10T19:44:44Z","cross_cats_sorted":[],"title_canon_sha256":"024a22d8f7688bfed5b562eaae781a01765b7334662f8747ad5c8b6b16488b1e","abstract_canon_sha256":"8f37d44d8af5c205958321f483811ecc69f96fb5eb5bb1de8be54754ee96c3db"},"schema_version":"1.0"},"canonical_sha256":"0212d3d6c9615655ec03e68ec05d3d2f3122db797bf88c88f6d7319ba74e419b","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:24:47.228846Z","signature_b64":"W9cq/+JO69pJ6a+CIBZkLlXRqd4FLwdYvTdLliJqdMi22LcYeXHPxWzoF/NHVhvc5FYckw7F+FzlyBcL2fieAw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"0212d3d6c9615655ec03e68ec05d3d2f3122db797bf88c88f6d7319ba74e419b","last_reissued_at":"2026-05-18T02:24:47.228157Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:24:47.228157Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"0909.1997","source_version":3,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T02:24:47Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"wmG58m1fErJu9zk0VMbUFPY0Kikdp9LM82SCykIUThMWhCF9BPL3ZRNV4YrJjwWyOLU8MFmostmViGbITQdtAw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-26T07:53:19.336194Z"},"content_sha256":"d6e1be6ce6f861f45d3ec67b685a7e2d1471593b8cd2b7f7cf6c3ffae702308d","schema_version":"1.0","event_id":"sha256:d6e1be6ce6f861f45d3ec67b685a7e2d1471593b8cd2b7f7cf6c3ffae702308d"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2009:AIJNHVWJMFLFL3AD42HMAXJ5F4","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Sources of the Radio Background Considered","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"A. Lawrence, J. Singal, L. Stawarz, V. Petrosian","submitted_at":"2009-09-10T19:44:44Z","abstract_excerpt":"We investigate different scenarios for the origin of the extragalactic radio background. The surface brightness of the background, as reported by the ARCADE 2 collaboration, is several times higher than that which would result from currently observed radio sources. We consider contributions to the background from diffuse synchrotron emission from clusters and the intergalactic medium, previously unrecognized flux from low surface brightness regions of radio sources, and faint point sources below the flux limit of existing surveys. By examining radio source counts available in the literature, w"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0909.1997","kind":"arxiv","version":3},"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":"2026-05-18T02:24:47Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"lvkvcWTz0FLc/+W3AT/BFc1509Kf0GmhclMKpKncm+ENeA8jJCERZXyGeP9kvF+PvlucmakiWaQTrV/GdsggCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-26T07:53:19.336889Z"},"content_sha256":"3cee083386e79a9ab4097eeb14b168f818e502f0e20479a1773726b0bb49cd69","schema_version":"1.0","event_id":"sha256:3cee083386e79a9ab4097eeb14b168f818e502f0e20479a1773726b0bb49cd69"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/AIJNHVWJMFLFL3AD42HMAXJ5F4/bundle.json","state_url":"https://pith.science/pith/AIJNHVWJMFLFL3AD42HMAXJ5F4/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/AIJNHVWJMFLFL3AD42HMAXJ5F4/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":"2026-05-26T07:53:19Z","links":{"resolver":"https://pith.science/pith/AIJNHVWJMFLFL3AD42HMAXJ5F4","bundle":"https://pith.science/pith/AIJNHVWJMFLFL3AD42HMAXJ5F4/bundle.json","state":"https://pith.science/pith/AIJNHVWJMFLFL3AD42HMAXJ5F4/state.json","well_known_bundle":"https://pith.science/.well-known/pith/AIJNHVWJMFLFL3AD42HMAXJ5F4/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2009:AIJNHVWJMFLFL3AD42HMAXJ5F4","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":"8f37d44d8af5c205958321f483811ecc69f96fb5eb5bb1de8be54754ee96c3db","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2009-09-10T19:44:44Z","title_canon_sha256":"024a22d8f7688bfed5b562eaae781a01765b7334662f8747ad5c8b6b16488b1e"},"schema_version":"1.0","source":{"id":"0909.1997","kind":"arxiv","version":3}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"0909.1997","created_at":"2026-05-18T02:24:47Z"},{"alias_kind":"arxiv_version","alias_value":"0909.1997v3","created_at":"2026-05-18T02:24:47Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.0909.1997","created_at":"2026-05-18T02:24:47Z"},{"alias_kind":"pith_short_12","alias_value":"AIJNHVWJMFLF","created_at":"2026-05-18T12:25:58Z"},{"alias_kind":"pith_short_16","alias_value":"AIJNHVWJMFLFL3AD","created_at":"2026-05-18T12:25:58Z"},{"alias_kind":"pith_short_8","alias_value":"AIJNHVWJ","created_at":"2026-05-18T12:25:58Z"}],"graph_snapshots":[{"event_id":"sha256:3cee083386e79a9ab4097eeb14b168f818e502f0e20479a1773726b0bb49cd69","target":"graph","created_at":"2026-05-18T02:24:47Z","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 investigate different scenarios for the origin of the extragalactic radio background. The surface brightness of the background, as reported by the ARCADE 2 collaboration, is several times higher than that which would result from currently observed radio sources. We consider contributions to the background from diffuse synchrotron emission from clusters and the intergalactic medium, previously unrecognized flux from low surface brightness regions of radio sources, and faint point sources below the flux limit of existing surveys. By examining radio source counts available in the literature, w","authors_text":"A. Lawrence, J. Singal, L. Stawarz, V. Petrosian","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2009-09-10T19:44:44Z","title":"Sources of the Radio Background Considered"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0909.1997","kind":"arxiv","version":3},"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:d6e1be6ce6f861f45d3ec67b685a7e2d1471593b8cd2b7f7cf6c3ffae702308d","target":"record","created_at":"2026-05-18T02:24:47Z","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":"8f37d44d8af5c205958321f483811ecc69f96fb5eb5bb1de8be54754ee96c3db","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2009-09-10T19:44:44Z","title_canon_sha256":"024a22d8f7688bfed5b562eaae781a01765b7334662f8747ad5c8b6b16488b1e"},"schema_version":"1.0","source":{"id":"0909.1997","kind":"arxiv","version":3}},"canonical_sha256":"0212d3d6c9615655ec03e68ec05d3d2f3122db797bf88c88f6d7319ba74e419b","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"0212d3d6c9615655ec03e68ec05d3d2f3122db797bf88c88f6d7319ba74e419b","first_computed_at":"2026-05-18T02:24:47.228157Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:24:47.228157Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"W9cq/+JO69pJ6a+CIBZkLlXRqd4FLwdYvTdLliJqdMi22LcYeXHPxWzoF/NHVhvc5FYckw7F+FzlyBcL2fieAw==","signature_status":"signed_v1","signed_at":"2026-05-18T02:24:47.228846Z","signed_message":"canonical_sha256_bytes"},"source_id":"0909.1997","source_kind":"arxiv","source_version":3}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:d6e1be6ce6f861f45d3ec67b685a7e2d1471593b8cd2b7f7cf6c3ffae702308d","sha256:3cee083386e79a9ab4097eeb14b168f818e502f0e20479a1773726b0bb49cd69"],"state_sha256":"a901341d4fd92d516bdde3d9bacd0136d5aa484f9ff7903caaf7cc26967ff042"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ebzkaJuWYs7Sl5QTc3OW85r6V+3YKJp/qC+piD5oVqh3IMy1/tOHNO/ouV+aWh9Ylxl7mL4dPHpHyPWgnZxiCQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-26T07:53:19.339718Z","bundle_sha256":"3ba9fff962f790e647232890cd8b2429918367a8f245db43db6e160621f04d40"}}