{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:1999:EJ7PPTII5MZXZEKZ2OPIYVOUQW","short_pith_number":"pith:EJ7PPTII","canonical_record":{"source":{"id":"astro-ph/9911339","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"1999-11-17T17:18:09Z","cross_cats_sorted":[],"title_canon_sha256":"59f444cdc7daadc3ec925ea868f8bf517573b1c1947c22b182d5fa269a3b4429","abstract_canon_sha256":"d738466f7d8f1456dc6ff3bbca6d1bdd2313b99acf1ad32cbebffbfe2ce10c0b"},"schema_version":"1.0"},"canonical_sha256":"227ef7cd08eb337c9159d39e8c55d485a3788e6252d649c2cea064883b9c2fcd","source":{"kind":"arxiv","id":"astro-ph/9911339","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/9911339","created_at":"2026-05-18T01:07:35Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/9911339v1","created_at":"2026-05-18T01:07:35Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/9911339","created_at":"2026-05-18T01:07:35Z"},{"alias_kind":"pith_short_12","alias_value":"EJ7PPTII5MZX","created_at":"2026-05-18T12:25:49Z"},{"alias_kind":"pith_short_16","alias_value":"EJ7PPTII5MZXZEKZ","created_at":"2026-05-18T12:25:49Z"},{"alias_kind":"pith_short_8","alias_value":"EJ7PPTII","created_at":"2026-05-18T12:25:49Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:1999:EJ7PPTII5MZXZEKZ2OPIYVOUQW","target":"record","payload":{"canonical_record":{"source":{"id":"astro-ph/9911339","kind":"arxiv","version":1},"metadata":{"license":"","primary_cat":"astro-ph","submitted_at":"1999-11-17T17:18:09Z","cross_cats_sorted":[],"title_canon_sha256":"59f444cdc7daadc3ec925ea868f8bf517573b1c1947c22b182d5fa269a3b4429","abstract_canon_sha256":"d738466f7d8f1456dc6ff3bbca6d1bdd2313b99acf1ad32cbebffbfe2ce10c0b"},"schema_version":"1.0"},"canonical_sha256":"227ef7cd08eb337c9159d39e8c55d485a3788e6252d649c2cea064883b9c2fcd","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:07:35.794746Z","signature_b64":"Y2haFOii33t3HJsV+AEMDMQEpYLBPmOQJ3yHdvj0Jp7EoNIcZmVPXIAi03cQunjDts12JwTQHpJ5m5jvIBAsAw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"227ef7cd08eb337c9159d39e8c55d485a3788e6252d649c2cea064883b9c2fcd","last_reissued_at":"2026-05-18T01:07:35.794125Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:07:35.794125Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"astro-ph/9911339","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":"2026-05-18T01:07:35Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"XO7cKcyLdn1shHtmXF3gEoiZLdVFRtABaZjKM1FinBP4jYOMdhPh1O7XnDhdKBYpQutJAJSNqXoUkHvPj4/0Bg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-01T12:40:22.512660Z"},"content_sha256":"8713a510421e228e07da8b2cd36a75351f2b43b3f085cc63d484b4a774abb135","schema_version":"1.0","event_id":"sha256:8713a510421e228e07da8b2cd36a75351f2b43b3f085cc63d484b4a774abb135"},{"event_type":"graph_snapshot","subject_pith_number":"pith:1999:EJ7PPTII5MZXZEKZ2OPIYVOUQW","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Zero-Metallicity Stars and the Effects of the First Stars on Reionization","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"Jason Tumlinson, J. Michael Shull","submitted_at":"1999-11-17T17:18:09Z","abstract_excerpt":"We present stellar structure and atmosphere models of metal-free stars and examine them from a cosmological point of view. Metal-free stars exhibit high effective temperatures and small sizes relative to metal-enriched stars of equal mass. These unique physical characteristics enhance the ionizing photon production by metal-free stars, particularly in the He II (E > = 4 Ryd) continuum. The star formation rate of metal-free stars necessary to reionize the hydrogen in the universe by z = 5 is consistent with the inferred star formation rate at that epoch. However, the hard stellar spectra are in"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/9911339","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":"2026-05-18T01:07:35Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"sWGQmu8MjblABIRTgWqN7trc3mol6E2tVAIGwrycVQfCvOIX2M/AxxFX6HHfpdaDHIui291KBT3ldgd4JQNvDA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-01T12:40:22.513013Z"},"content_sha256":"caf7117ed95dde7ea31e82c0f7ff51e0fc162d4bf139f7d2f220ad0b7997f2fb","schema_version":"1.0","event_id":"sha256:caf7117ed95dde7ea31e82c0f7ff51e0fc162d4bf139f7d2f220ad0b7997f2fb"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/EJ7PPTII5MZXZEKZ2OPIYVOUQW/bundle.json","state_url":"https://pith.science/pith/EJ7PPTII5MZXZEKZ2OPIYVOUQW/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/EJ7PPTII5MZXZEKZ2OPIYVOUQW/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":"2026-06-01T12:40:22Z","links":{"resolver":"https://pith.science/pith/EJ7PPTII5MZXZEKZ2OPIYVOUQW","bundle":"https://pith.science/pith/EJ7PPTII5MZXZEKZ2OPIYVOUQW/bundle.json","state":"https://pith.science/pith/EJ7PPTII5MZXZEKZ2OPIYVOUQW/state.json","well_known_bundle":"https://pith.science/.well-known/pith/EJ7PPTII5MZXZEKZ2OPIYVOUQW/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:1999:EJ7PPTII5MZXZEKZ2OPIYVOUQW","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":"d738466f7d8f1456dc6ff3bbca6d1bdd2313b99acf1ad32cbebffbfe2ce10c0b","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"1999-11-17T17:18:09Z","title_canon_sha256":"59f444cdc7daadc3ec925ea868f8bf517573b1c1947c22b182d5fa269a3b4429"},"schema_version":"1.0","source":{"id":"astro-ph/9911339","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"astro-ph/9911339","created_at":"2026-05-18T01:07:35Z"},{"alias_kind":"arxiv_version","alias_value":"astro-ph/9911339v1","created_at":"2026-05-18T01:07:35Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.astro-ph/9911339","created_at":"2026-05-18T01:07:35Z"},{"alias_kind":"pith_short_12","alias_value":"EJ7PPTII5MZX","created_at":"2026-05-18T12:25:49Z"},{"alias_kind":"pith_short_16","alias_value":"EJ7PPTII5MZXZEKZ","created_at":"2026-05-18T12:25:49Z"},{"alias_kind":"pith_short_8","alias_value":"EJ7PPTII","created_at":"2026-05-18T12:25:49Z"}],"graph_snapshots":[{"event_id":"sha256:caf7117ed95dde7ea31e82c0f7ff51e0fc162d4bf139f7d2f220ad0b7997f2fb","target":"graph","created_at":"2026-05-18T01:07:35Z","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 stellar structure and atmosphere models of metal-free stars and examine them from a cosmological point of view. Metal-free stars exhibit high effective temperatures and small sizes relative to metal-enriched stars of equal mass. These unique physical characteristics enhance the ionizing photon production by metal-free stars, particularly in the He II (E > = 4 Ryd) continuum. The star formation rate of metal-free stars necessary to reionize the hydrogen in the universe by z = 5 is consistent with the inferred star formation rate at that epoch. However, the hard stellar spectra are in","authors_text":"Jason Tumlinson, J. Michael Shull","cross_cats":[],"headline":"","license":"","primary_cat":"astro-ph","submitted_at":"1999-11-17T17:18:09Z","title":"Zero-Metallicity Stars and the Effects of the First Stars on Reionization"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/9911339","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":"sha256:8713a510421e228e07da8b2cd36a75351f2b43b3f085cc63d484b4a774abb135","target":"record","created_at":"2026-05-18T01:07:35Z","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":"d738466f7d8f1456dc6ff3bbca6d1bdd2313b99acf1ad32cbebffbfe2ce10c0b","cross_cats_sorted":[],"license":"","primary_cat":"astro-ph","submitted_at":"1999-11-17T17:18:09Z","title_canon_sha256":"59f444cdc7daadc3ec925ea868f8bf517573b1c1947c22b182d5fa269a3b4429"},"schema_version":"1.0","source":{"id":"astro-ph/9911339","kind":"arxiv","version":1}},"canonical_sha256":"227ef7cd08eb337c9159d39e8c55d485a3788e6252d649c2cea064883b9c2fcd","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"227ef7cd08eb337c9159d39e8c55d485a3788e6252d649c2cea064883b9c2fcd","first_computed_at":"2026-05-18T01:07:35.794125Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:07:35.794125Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"Y2haFOii33t3HJsV+AEMDMQEpYLBPmOQJ3yHdvj0Jp7EoNIcZmVPXIAi03cQunjDts12JwTQHpJ5m5jvIBAsAw==","signature_status":"signed_v1","signed_at":"2026-05-18T01:07:35.794746Z","signed_message":"canonical_sha256_bytes"},"source_id":"astro-ph/9911339","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:8713a510421e228e07da8b2cd36a75351f2b43b3f085cc63d484b4a774abb135","sha256:caf7117ed95dde7ea31e82c0f7ff51e0fc162d4bf139f7d2f220ad0b7997f2fb"],"state_sha256":"f3f5c7b081c10fd867658caf51eb01bf0011f8c11cbeb526d5aabe32031d252c"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"LvmplX/NyDu+xLLM/4bjchzdFPpfhVnmgGxNNVC/9xXVOGkoOOw1L/tmQxflb7vrRQDY2VzikqPxYQH7EHXwAg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-01T12:40:22.515199Z","bundle_sha256":"1ae8aa26865faec8d129bcaf34e8792d106663edd1242f2d91261d5da646e397"}}