{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2015:HWAD2IFOUMTOEF5LQUN6NISJEW","short_pith_number":"pith:HWAD2IFO","canonical_record":{"source":{"id":"1504.02480","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2015-04-09T20:01:22Z","cross_cats_sorted":[],"title_canon_sha256":"05098e145895e6461ccc333f4a5d8f42d99071ca57679fa48f07a5484aef7142","abstract_canon_sha256":"29416a03d9f1163a01b15d82f17eccb842b8f210cceb4ba0ea75fc6cd9eb0f1e"},"schema_version":"1.0"},"canonical_sha256":"3d803d20aea326e217ab851be6a24925a856fd2876df41c81ce78584038b2cd5","source":{"kind":"arxiv","id":"1504.02480","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1504.02480","created_at":"2026-05-18T02:04:05Z"},{"alias_kind":"arxiv_version","alias_value":"1504.02480v1","created_at":"2026-05-18T02:04:05Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1504.02480","created_at":"2026-05-18T02:04:05Z"},{"alias_kind":"pith_short_12","alias_value":"HWAD2IFOUMTO","created_at":"2026-05-18T12:29:25Z"},{"alias_kind":"pith_short_16","alias_value":"HWAD2IFOUMTOEF5L","created_at":"2026-05-18T12:29:25Z"},{"alias_kind":"pith_short_8","alias_value":"HWAD2IFO","created_at":"2026-05-18T12:29:25Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2015:HWAD2IFOUMTOEF5LQUN6NISJEW","target":"record","payload":{"canonical_record":{"source":{"id":"1504.02480","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2015-04-09T20:01:22Z","cross_cats_sorted":[],"title_canon_sha256":"05098e145895e6461ccc333f4a5d8f42d99071ca57679fa48f07a5484aef7142","abstract_canon_sha256":"29416a03d9f1163a01b15d82f17eccb842b8f210cceb4ba0ea75fc6cd9eb0f1e"},"schema_version":"1.0"},"canonical_sha256":"3d803d20aea326e217ab851be6a24925a856fd2876df41c81ce78584038b2cd5","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:04:05.634616Z","signature_b64":"42Hy8jG2H3GHsi9YaaffzSrlwyi9WznYCSl5OYT7ej8Db3A2Jh1o1Dafqfww71j40imq4GlrkPTXCB9QyFO5BQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"3d803d20aea326e217ab851be6a24925a856fd2876df41c81ce78584038b2cd5","last_reissued_at":"2026-05-18T02:04:05.633879Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:04:05.633879Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1504.02480","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":"2026-05-18T02:04:05Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"QTviC7RD890QtmBrx8GFmu+6M/SkqpAFF6l5aBFfbdgW5wGaDUmjr6rbhU1RieR54W094vAHNXHO6wFxUyRvDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-12T10:09:26.509453Z"},"content_sha256":"6353703265ae1e3f6a7ce5a52c2bb98bd2d51ae0eb9e5471b30fec78202a2d83","schema_version":"1.0","event_id":"sha256:6353703265ae1e3f6a7ce5a52c2bb98bd2d51ae0eb9e5471b30fec78202a2d83"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2015:HWAD2IFOUMTOEF5LQUN6NISJEW","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"The Chemical Evolution of Very Metal-Poor Damped Lyman-$\\alpha$ Systems","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"David Webster, Joss Bland-Hawthorn, Ralph S. Sutherland","submitted_at":"2015-04-09T20:01:22Z","abstract_excerpt":"In earlier work we showed that a dark matter halo with a virial mass of $10^7$ M$_\\odot$ can survive feedback from its own massive stars and form stars for $\\gtrsim100$ Myr. We also found that our modelled systems were consistent with observations of ultrafaint dwarfs (UFDs), the least massive known galaxies. Very metal-poor damped Lyman-$\\alpha$ systems (DLAs) recently identified at $z\\sim2$ may represent the gas that formed at least some of the observed stars in UFDs. We compare projected sightlines from our simulations to the observed metal-poor DLAs and find that our models can reach the d"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1504.02480","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":"2026-05-18T02:04:05Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"M2Jh4vRBRAgRltRdkl1C8eJksBEgmPV6q3acI7LOyFRjs8wU8iLfGEk4o6jTcNGFmC2us3Dd3czHHUJlq1QjAg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-12T10:09:26.510079Z"},"content_sha256":"b2da436d3d6ccc22baa06c4bf2965b56ccd679974f8c36e955a5680a2d97b913","schema_version":"1.0","event_id":"sha256:b2da436d3d6ccc22baa06c4bf2965b56ccd679974f8c36e955a5680a2d97b913"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/HWAD2IFOUMTOEF5LQUN6NISJEW/bundle.json","state_url":"https://pith.science/pith/HWAD2IFOUMTOEF5LQUN6NISJEW/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/HWAD2IFOUMTOEF5LQUN6NISJEW/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":"2026-06-12T10:09:26Z","links":{"resolver":"https://pith.science/pith/HWAD2IFOUMTOEF5LQUN6NISJEW","bundle":"https://pith.science/pith/HWAD2IFOUMTOEF5LQUN6NISJEW/bundle.json","state":"https://pith.science/pith/HWAD2IFOUMTOEF5LQUN6NISJEW/state.json","well_known_bundle":"https://pith.science/.well-known/pith/HWAD2IFOUMTOEF5LQUN6NISJEW/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2015:HWAD2IFOUMTOEF5LQUN6NISJEW","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":"29416a03d9f1163a01b15d82f17eccb842b8f210cceb4ba0ea75fc6cd9eb0f1e","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2015-04-09T20:01:22Z","title_canon_sha256":"05098e145895e6461ccc333f4a5d8f42d99071ca57679fa48f07a5484aef7142"},"schema_version":"1.0","source":{"id":"1504.02480","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1504.02480","created_at":"2026-05-18T02:04:05Z"},{"alias_kind":"arxiv_version","alias_value":"1504.02480v1","created_at":"2026-05-18T02:04:05Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1504.02480","created_at":"2026-05-18T02:04:05Z"},{"alias_kind":"pith_short_12","alias_value":"HWAD2IFOUMTO","created_at":"2026-05-18T12:29:25Z"},{"alias_kind":"pith_short_16","alias_value":"HWAD2IFOUMTOEF5L","created_at":"2026-05-18T12:29:25Z"},{"alias_kind":"pith_short_8","alias_value":"HWAD2IFO","created_at":"2026-05-18T12:29:25Z"}],"graph_snapshots":[{"event_id":"sha256:b2da436d3d6ccc22baa06c4bf2965b56ccd679974f8c36e955a5680a2d97b913","target":"graph","created_at":"2026-05-18T02:04:05Z","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":"In earlier work we showed that a dark matter halo with a virial mass of $10^7$ M$_\\odot$ can survive feedback from its own massive stars and form stars for $\\gtrsim100$ Myr. We also found that our modelled systems were consistent with observations of ultrafaint dwarfs (UFDs), the least massive known galaxies. Very metal-poor damped Lyman-$\\alpha$ systems (DLAs) recently identified at $z\\sim2$ may represent the gas that formed at least some of the observed stars in UFDs. We compare projected sightlines from our simulations to the observed metal-poor DLAs and find that our models can reach the d","authors_text":"David Webster, Joss Bland-Hawthorn, Ralph S. Sutherland","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2015-04-09T20:01:22Z","title":"The Chemical Evolution of Very Metal-Poor Damped Lyman-$\\alpha$ Systems"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1504.02480","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":"sha256:6353703265ae1e3f6a7ce5a52c2bb98bd2d51ae0eb9e5471b30fec78202a2d83","target":"record","created_at":"2026-05-18T02:04:05Z","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":"29416a03d9f1163a01b15d82f17eccb842b8f210cceb4ba0ea75fc6cd9eb0f1e","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2015-04-09T20:01:22Z","title_canon_sha256":"05098e145895e6461ccc333f4a5d8f42d99071ca57679fa48f07a5484aef7142"},"schema_version":"1.0","source":{"id":"1504.02480","kind":"arxiv","version":1}},"canonical_sha256":"3d803d20aea326e217ab851be6a24925a856fd2876df41c81ce78584038b2cd5","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"3d803d20aea326e217ab851be6a24925a856fd2876df41c81ce78584038b2cd5","first_computed_at":"2026-05-18T02:04:05.633879Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:04:05.633879Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"42Hy8jG2H3GHsi9YaaffzSrlwyi9WznYCSl5OYT7ej8Db3A2Jh1o1Dafqfww71j40imq4GlrkPTXCB9QyFO5BQ==","signature_status":"signed_v1","signed_at":"2026-05-18T02:04:05.634616Z","signed_message":"canonical_sha256_bytes"},"source_id":"1504.02480","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:6353703265ae1e3f6a7ce5a52c2bb98bd2d51ae0eb9e5471b30fec78202a2d83","sha256:b2da436d3d6ccc22baa06c4bf2965b56ccd679974f8c36e955a5680a2d97b913"],"state_sha256":"5698aceecff7439f2376b2ffa49f753a5c56293ed6d71aa314a87dc703a24d8a"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"clSdwLM6ysarGI3ODZf3vE7JZnpa9BjFgwngpsmLQD9fIkgxeWH0+sRLhkCjGvg84Te2YkXTA3N5VoDOeGRwCw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-12T10:09:26.513049Z","bundle_sha256":"c3553e8335622deb4011da9feb25ae27c179f0afc7779379daaa2f56da40b33c"}}