{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2011:XSKDKGGUV6XJEPWVP4SUENIBKX","short_pith_number":"pith:XSKDKGGU","canonical_record":{"source":{"id":"1103.5752","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2011-03-29T20:01:15Z","cross_cats_sorted":[],"title_canon_sha256":"066504da6cb96bcc0f7e69c7fa6443a2cc3c101a0e53a543ec62c4254cb7fbc2","abstract_canon_sha256":"81c1748be19e1e9a6dbf699c0a3a1b014f8eb0f271b6b6f5d5854137e17ef151"},"schema_version":"1.0"},"canonical_sha256":"bc943518d4afae923ed57f2542350155ca7550e4595e51fbedea6a46030ef0bd","source":{"kind":"arxiv","id":"1103.5752","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1103.5752","created_at":"2026-05-18T04:22:21Z"},{"alias_kind":"arxiv_version","alias_value":"1103.5752v2","created_at":"2026-05-18T04:22:21Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1103.5752","created_at":"2026-05-18T04:22:21Z"},{"alias_kind":"pith_short_12","alias_value":"XSKDKGGUV6XJ","created_at":"2026-05-18T12:26:47Z"},{"alias_kind":"pith_short_16","alias_value":"XSKDKGGUV6XJEPWV","created_at":"2026-05-18T12:26:47Z"},{"alias_kind":"pith_short_8","alias_value":"XSKDKGGU","created_at":"2026-05-18T12:26:47Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2011:XSKDKGGUV6XJEPWVP4SUENIBKX","target":"record","payload":{"canonical_record":{"source":{"id":"1103.5752","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2011-03-29T20:01:15Z","cross_cats_sorted":[],"title_canon_sha256":"066504da6cb96bcc0f7e69c7fa6443a2cc3c101a0e53a543ec62c4254cb7fbc2","abstract_canon_sha256":"81c1748be19e1e9a6dbf699c0a3a1b014f8eb0f271b6b6f5d5854137e17ef151"},"schema_version":"1.0"},"canonical_sha256":"bc943518d4afae923ed57f2542350155ca7550e4595e51fbedea6a46030ef0bd","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T04:22:21.752667Z","signature_b64":"aTRoQtYs38I7rJv8Ad2sQa80d71H1gfWy8jfamztjq+urmPkyAk1xu9nZvfWoNs2yjGdwBCjYzqzmC8Aw2c3Cg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"bc943518d4afae923ed57f2542350155ca7550e4595e51fbedea6a46030ef0bd","last_reissued_at":"2026-05-18T04:22:21.751928Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T04:22:21.751928Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1103.5752","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":"2026-05-18T04:22:21Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"lVK0+rPUPOthxIg5GMSd50VSo6Bb9TDYcmGrUI2qpm8nmGldCUVReYL1GxOs0TmNul0Cpo6t3ac6+mZf5TAeCA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-26T22:17:24.005749Z"},"content_sha256":"5b9d1f1c28056181ff10f74fce2c5d99bdd33e17bca02816806498f018750893","schema_version":"1.0","event_id":"sha256:5b9d1f1c28056181ff10f74fce2c5d99bdd33e17bca02816806498f018750893"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2011:XSKDKGGUV6XJEPWVP4SUENIBKX","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"The End of Helium Reionization at z~2.7 Inferred from Cosmic Variance in HST/COS HeII Lyman Alpha Absorption Spectra","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.CO","authors_text":"(2) University of California Berkeley, (3) Astrophysikalisches Institut Potsdam, (4) Universit\\\"at Potsdam, (5) Max-Planck-Institut f\\\"ur Astronomie, (6) Hamburger Sternwarte/Universit\\\"at Hamburg), Aldo Dall'Aglio (3), Cora Fechner (4), Dieter Reimers (6), G\\'abor Worseck (1), Joseph F. Hennawi (5), J. Xavier Prochaska (1), Lutz Wisotzki (3) ((1) UCO/Lick Observatory at University of California Santa Cruz, Matthew McQuinn (2), Philipp Richter (4)","submitted_at":"2011-03-29T20:01:15Z","abstract_excerpt":"We report on the detection of strongly varying intergalactic HeII absorption in HST/COS spectra of two z~3 quasars. From our homogeneous analysis of the HeII absorption in these and three archival sightlines, we find a marked increase in the mean HeII effective optical depth from tau~1 at z~2.3 to tau>5 at z~3.2, but with a large scatter of 2< tau <5 at 2.7< z <3 on scales of ~10 proper Mpc. This scatter is primarily due to fluctuations in the HeII fraction and the HeII-ionizing background, rather than density variations that are probed by the co-eval HI forest. Semianalytic models of HeII abs"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1103.5752","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":"2026-05-18T04:22:21Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ohHrYkmwYiQyGq6W3oJfJg3qwBBqJLhVyVaFAvW33XK5WeLH3XRrnwS481zj1JJnR0Pk3sawgIerSsvXk/2fBg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-26T22:17:24.006145Z"},"content_sha256":"07b129ff2a5b7696fc86da7ae975bcfbeeeef2e1147eb85f7045c9ebafb5e823","schema_version":"1.0","event_id":"sha256:07b129ff2a5b7696fc86da7ae975bcfbeeeef2e1147eb85f7045c9ebafb5e823"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/XSKDKGGUV6XJEPWVP4SUENIBKX/bundle.json","state_url":"https://pith.science/pith/XSKDKGGUV6XJEPWVP4SUENIBKX/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/XSKDKGGUV6XJEPWVP4SUENIBKX/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":"2026-05-26T22:17:24Z","links":{"resolver":"https://pith.science/pith/XSKDKGGUV6XJEPWVP4SUENIBKX","bundle":"https://pith.science/pith/XSKDKGGUV6XJEPWVP4SUENIBKX/bundle.json","state":"https://pith.science/pith/XSKDKGGUV6XJEPWVP4SUENIBKX/state.json","well_known_bundle":"https://pith.science/.well-known/pith/XSKDKGGUV6XJEPWVP4SUENIBKX/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2011:XSKDKGGUV6XJEPWVP4SUENIBKX","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":"81c1748be19e1e9a6dbf699c0a3a1b014f8eb0f271b6b6f5d5854137e17ef151","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2011-03-29T20:01:15Z","title_canon_sha256":"066504da6cb96bcc0f7e69c7fa6443a2cc3c101a0e53a543ec62c4254cb7fbc2"},"schema_version":"1.0","source":{"id":"1103.5752","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1103.5752","created_at":"2026-05-18T04:22:21Z"},{"alias_kind":"arxiv_version","alias_value":"1103.5752v2","created_at":"2026-05-18T04:22:21Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1103.5752","created_at":"2026-05-18T04:22:21Z"},{"alias_kind":"pith_short_12","alias_value":"XSKDKGGUV6XJ","created_at":"2026-05-18T12:26:47Z"},{"alias_kind":"pith_short_16","alias_value":"XSKDKGGUV6XJEPWV","created_at":"2026-05-18T12:26:47Z"},{"alias_kind":"pith_short_8","alias_value":"XSKDKGGU","created_at":"2026-05-18T12:26:47Z"}],"graph_snapshots":[{"event_id":"sha256:07b129ff2a5b7696fc86da7ae975bcfbeeeef2e1147eb85f7045c9ebafb5e823","target":"graph","created_at":"2026-05-18T04:22:21Z","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 report on the detection of strongly varying intergalactic HeII absorption in HST/COS spectra of two z~3 quasars. From our homogeneous analysis of the HeII absorption in these and three archival sightlines, we find a marked increase in the mean HeII effective optical depth from tau~1 at z~2.3 to tau>5 at z~3.2, but with a large scatter of 2< tau <5 at 2.7< z <3 on scales of ~10 proper Mpc. This scatter is primarily due to fluctuations in the HeII fraction and the HeII-ionizing background, rather than density variations that are probed by the co-eval HI forest. Semianalytic models of HeII abs","authors_text":"(2) University of California Berkeley, (3) Astrophysikalisches Institut Potsdam, (4) Universit\\\"at Potsdam, (5) Max-Planck-Institut f\\\"ur Astronomie, (6) Hamburger Sternwarte/Universit\\\"at Hamburg), Aldo Dall'Aglio (3), Cora Fechner (4), Dieter Reimers (6), G\\'abor Worseck (1), Joseph F. Hennawi (5), J. Xavier Prochaska (1), Lutz Wisotzki (3) ((1) UCO/Lick Observatory at University of California Santa Cruz, Matthew McQuinn (2), Philipp Richter (4)","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2011-03-29T20:01:15Z","title":"The End of Helium Reionization at z~2.7 Inferred from Cosmic Variance in HST/COS HeII Lyman Alpha Absorption Spectra"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1103.5752","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":"sha256:5b9d1f1c28056181ff10f74fce2c5d99bdd33e17bca02816806498f018750893","target":"record","created_at":"2026-05-18T04:22:21Z","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":"81c1748be19e1e9a6dbf699c0a3a1b014f8eb0f271b6b6f5d5854137e17ef151","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2011-03-29T20:01:15Z","title_canon_sha256":"066504da6cb96bcc0f7e69c7fa6443a2cc3c101a0e53a543ec62c4254cb7fbc2"},"schema_version":"1.0","source":{"id":"1103.5752","kind":"arxiv","version":2}},"canonical_sha256":"bc943518d4afae923ed57f2542350155ca7550e4595e51fbedea6a46030ef0bd","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"bc943518d4afae923ed57f2542350155ca7550e4595e51fbedea6a46030ef0bd","first_computed_at":"2026-05-18T04:22:21.751928Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T04:22:21.751928Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"aTRoQtYs38I7rJv8Ad2sQa80d71H1gfWy8jfamztjq+urmPkyAk1xu9nZvfWoNs2yjGdwBCjYzqzmC8Aw2c3Cg==","signature_status":"signed_v1","signed_at":"2026-05-18T04:22:21.752667Z","signed_message":"canonical_sha256_bytes"},"source_id":"1103.5752","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:5b9d1f1c28056181ff10f74fce2c5d99bdd33e17bca02816806498f018750893","sha256:07b129ff2a5b7696fc86da7ae975bcfbeeeef2e1147eb85f7045c9ebafb5e823"],"state_sha256":"2cf85aa581a551f285b47e99b9cd25eb92216e87bd413062286f2ffd5e305416"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"qX3dGvVqyOfDt7fUI1yUMMABMHVTh74yHUsdfKXb7LZSHr+VRi+dHzuQ6aDJlgI3grGR89hs2+d1q4f/rMnsBQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-26T22:17:24.009303Z","bundle_sha256":"60097d4bc479e9e5cb637432594db692287a3841b2c7bb8d2eccc4bbf4647f17"}}