{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:WWA727XMNSGK52LZPSJNUTSOBQ","short_pith_number":"pith:WWA727XM","canonical_record":{"source":{"id":"1807.05334","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-07-14T05:33:50Z","cross_cats_sorted":[],"title_canon_sha256":"d682cbdf661bc1edd272892e09456e1987685baa177192707f6a056ef46c305d","abstract_canon_sha256":"de90a265a8ff45964ae5d2930f35b01343d61cbcb0b12219f1261e77015238d8"},"schema_version":"1.0"},"canonical_sha256":"b581fd7eec6c8caee9797c92da4e4e0c16a742a8418b40212338758c88b1f765","source":{"kind":"arxiv","id":"1807.05334","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1807.05334","created_at":"2026-05-18T00:09:10Z"},{"alias_kind":"arxiv_version","alias_value":"1807.05334v1","created_at":"2026-05-18T00:09:10Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1807.05334","created_at":"2026-05-18T00:09:10Z"},{"alias_kind":"pith_short_12","alias_value":"WWA727XMNSGK","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_16","alias_value":"WWA727XMNSGK52LZ","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_8","alias_value":"WWA727XM","created_at":"2026-05-18T12:33:01Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:WWA727XMNSGK52LZPSJNUTSOBQ","target":"record","payload":{"canonical_record":{"source":{"id":"1807.05334","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-07-14T05:33:50Z","cross_cats_sorted":[],"title_canon_sha256":"d682cbdf661bc1edd272892e09456e1987685baa177192707f6a056ef46c305d","abstract_canon_sha256":"de90a265a8ff45964ae5d2930f35b01343d61cbcb0b12219f1261e77015238d8"},"schema_version":"1.0"},"canonical_sha256":"b581fd7eec6c8caee9797c92da4e4e0c16a742a8418b40212338758c88b1f765","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:09:10.858704Z","signature_b64":"XqOLnwXzMfx3vpZAynKfg9eNhBN1IfhFe3n9PeEddrpZ4fh345Aybpravz/T5iCneSKSxuqU+wyl0XaYFGzdCQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"b581fd7eec6c8caee9797c92da4e4e0c16a742a8418b40212338758c88b1f765","last_reissued_at":"2026-05-18T00:09:10.858066Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:09:10.858066Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1807.05334","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":"2026-05-18T00:09:10Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"sO9791SO1upeanUruUSEDJQ984nAwm7KqrQwXnuZc5styqbWbNx+Ao8y6ilfDvhwcEjmWQZoXRaUci9o2iBYCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-03T20:25:50.319547Z"},"content_sha256":"fd050fd44ac5cabe22e7608227364325cdaf5e01e09334f7ee5d58bc1d021c49","schema_version":"1.0","event_id":"sha256:fd050fd44ac5cabe22e7608227364325cdaf5e01e09334f7ee5d58bc1d021c49"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:WWA727XMNSGK52LZPSJNUTSOBQ","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Condition for low-mass star formation in shock-compressed metal-poor clouds","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Daisuke Nakauchi, Kazuyuki Omukai, Raffaella Schneider","submitted_at":"2018-07-14T05:33:50Z","abstract_excerpt":"Shocks may have been prevalent in the early Universe, associated with virialization and supernova explosions, etc. Here, we study thermal evolution and fragmentation of shock-compressed clouds, by using a one-zone model with detailed thermal and chemical processes. We explore a large range of initial density (1-1e5 /cm^3), metallicity (0-1e-2 Z_sun), UV strength (0-500 times Galactic value), and cosmic microwave background temperature (10 and 30 K). Shock-compressed clouds contract isobarically via atomic and molecular line cooling, until self-gravitating clumps are formed by fragmentation. If"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1807.05334","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":"2026-05-18T00:09:10Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"b6BVYiBQRPCYzd1ExCvUPkw6MNWsqbvBaaY8PJYDoeOvWMnvpAkULDdY9wbP0YU/ETIE3CbTZ5fLpJxqaVvfAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-03T20:25:50.319921Z"},"content_sha256":"ad4bc5c8ad739505d3bbe56010ee7e2574b5066a452e7d5c61be1d85b064738f","schema_version":"1.0","event_id":"sha256:ad4bc5c8ad739505d3bbe56010ee7e2574b5066a452e7d5c61be1d85b064738f"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/WWA727XMNSGK52LZPSJNUTSOBQ/bundle.json","state_url":"https://pith.science/pith/WWA727XMNSGK52LZPSJNUTSOBQ/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/WWA727XMNSGK52LZPSJNUTSOBQ/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":"2026-06-03T20:25:50Z","links":{"resolver":"https://pith.science/pith/WWA727XMNSGK52LZPSJNUTSOBQ","bundle":"https://pith.science/pith/WWA727XMNSGK52LZPSJNUTSOBQ/bundle.json","state":"https://pith.science/pith/WWA727XMNSGK52LZPSJNUTSOBQ/state.json","well_known_bundle":"https://pith.science/.well-known/pith/WWA727XMNSGK52LZPSJNUTSOBQ/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:WWA727XMNSGK52LZPSJNUTSOBQ","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":"de90a265a8ff45964ae5d2930f35b01343d61cbcb0b12219f1261e77015238d8","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-07-14T05:33:50Z","title_canon_sha256":"d682cbdf661bc1edd272892e09456e1987685baa177192707f6a056ef46c305d"},"schema_version":"1.0","source":{"id":"1807.05334","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1807.05334","created_at":"2026-05-18T00:09:10Z"},{"alias_kind":"arxiv_version","alias_value":"1807.05334v1","created_at":"2026-05-18T00:09:10Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1807.05334","created_at":"2026-05-18T00:09:10Z"},{"alias_kind":"pith_short_12","alias_value":"WWA727XMNSGK","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_16","alias_value":"WWA727XMNSGK52LZ","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_8","alias_value":"WWA727XM","created_at":"2026-05-18T12:33:01Z"}],"graph_snapshots":[{"event_id":"sha256:ad4bc5c8ad739505d3bbe56010ee7e2574b5066a452e7d5c61be1d85b064738f","target":"graph","created_at":"2026-05-18T00:09:10Z","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":"Shocks may have been prevalent in the early Universe, associated with virialization and supernova explosions, etc. Here, we study thermal evolution and fragmentation of shock-compressed clouds, by using a one-zone model with detailed thermal and chemical processes. We explore a large range of initial density (1-1e5 /cm^3), metallicity (0-1e-2 Z_sun), UV strength (0-500 times Galactic value), and cosmic microwave background temperature (10 and 30 K). Shock-compressed clouds contract isobarically via atomic and molecular line cooling, until self-gravitating clumps are formed by fragmentation. If","authors_text":"Daisuke Nakauchi, Kazuyuki Omukai, Raffaella Schneider","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-07-14T05:33:50Z","title":"Condition for low-mass star formation in shock-compressed metal-poor clouds"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1807.05334","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:fd050fd44ac5cabe22e7608227364325cdaf5e01e09334f7ee5d58bc1d021c49","target":"record","created_at":"2026-05-18T00:09:10Z","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":"de90a265a8ff45964ae5d2930f35b01343d61cbcb0b12219f1261e77015238d8","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-07-14T05:33:50Z","title_canon_sha256":"d682cbdf661bc1edd272892e09456e1987685baa177192707f6a056ef46c305d"},"schema_version":"1.0","source":{"id":"1807.05334","kind":"arxiv","version":1}},"canonical_sha256":"b581fd7eec6c8caee9797c92da4e4e0c16a742a8418b40212338758c88b1f765","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"b581fd7eec6c8caee9797c92da4e4e0c16a742a8418b40212338758c88b1f765","first_computed_at":"2026-05-18T00:09:10.858066Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:09:10.858066Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"XqOLnwXzMfx3vpZAynKfg9eNhBN1IfhFe3n9PeEddrpZ4fh345Aybpravz/T5iCneSKSxuqU+wyl0XaYFGzdCQ==","signature_status":"signed_v1","signed_at":"2026-05-18T00:09:10.858704Z","signed_message":"canonical_sha256_bytes"},"source_id":"1807.05334","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:fd050fd44ac5cabe22e7608227364325cdaf5e01e09334f7ee5d58bc1d021c49","sha256:ad4bc5c8ad739505d3bbe56010ee7e2574b5066a452e7d5c61be1d85b064738f"],"state_sha256":"bdcb3658dbb45669ad81ba9e530ffbc0ad4e6d94a71728ebd0e2fe914809ca42"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"eFkvV+twTAjHVz+EltetI/zN9GALlU1oIcETY/wp1VCFHWYwsKyx+DEIssRjKzDFHTsW7T55TH8xukguG1/mBw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-03T20:25:50.322580Z","bundle_sha256":"0acd9af97bb9b272c8fa9ad231ad5befdcfc8e866acb7efd98b01d708acb785f"}}