{"record_type":"pith_number_record","schema_url":"https://pith.science/schemas/pith-number/v1.json","pith_number":"pith:2012:JNO224ID4HJ6MT2TR5LHX73FUD","short_pith_number":"pith:JNO224ID","schema_version":"1.0","canonical_sha256":"4b5dad7103e1d3e64f538f567bff65a0f976451b077f96cbb7e24604039d2388","source":{"kind":"arxiv","id":"1209.0771","version":1},"attestation_state":"computed","paper":{"title":"Galaxy Gas Fractions at High-Redshift: The Tension between Observations and Cosmological Simulations","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.GA"],"primary_cat":"astro-ph.CO","authors_text":"Desika Narayanan (Arizona), Matt Bothwell (Arizona), Romeel Dave (Arizona)","submitted_at":"2012-09-04T20:00:04Z","abstract_excerpt":"CO measurements of z~1-4 galaxies have found that their baryonic gas fractions are significantly higher than galaxies at z=0, with values ranging from 20-80 %. Here, we suggest that the gas fractions inferred from observations of star-forming galaxies at high-z are overestimated, owing to the adoption of locally-calibrated CO-H2 conversion factors (Xco). Evidence from both observations and numerical models suggest that Xco varies smoothly with the physical properties of galaxies, and that Xco can be parameterised simply as a function of both gas phase metallicity and observed CO surface bright"},"verification_status":{"content_addressed":true,"pith_receipt":true,"author_attested":false,"weak_author_claims":0,"strong_author_claims":0,"externally_anchored":false,"storage_verified":false,"citation_signatures":0,"replication_records":0,"graph_snapshot":true,"references_resolved":false,"formal_links_present":false},"canonical_record":{"source":{"id":"1209.0771","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.CO","submitted_at":"2012-09-04T20:00:04Z","cross_cats_sorted":["astro-ph.GA"],"title_canon_sha256":"1f9a4cccc289cdb8f2cae1815581e861b157410df624816fa7efba4af11e5da8","abstract_canon_sha256":"b65b1ee21bfc6cbcc9fc8257dfc2d855dcfd5b41fa2b8faf20ad95163d2d4337"},"schema_version":"1.0"},"receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:54:40.620207Z","signature_b64":"myCR26OrHsKQOw5hh+33tjXjtkzt6oVm+dofa20Lh2PResh/qqCFwJdbi3lO2hSZTm/0OVQxTapaobZDfw7mBg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"4b5dad7103e1d3e64f538f567bff65a0f976451b077f96cbb7e24604039d2388","last_reissued_at":"2026-05-18T01:54:40.619549Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:54:40.619549Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"graph_snapshot":{"paper":{"title":"Galaxy Gas Fractions at High-Redshift: The Tension between Observations and Cosmological Simulations","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.GA"],"primary_cat":"astro-ph.CO","authors_text":"Desika Narayanan (Arizona), Matt Bothwell (Arizona), Romeel Dave (Arizona)","submitted_at":"2012-09-04T20:00:04Z","abstract_excerpt":"CO measurements of z~1-4 galaxies have found that their baryonic gas fractions are significantly higher than galaxies at z=0, with values ranging from 20-80 %. Here, we suggest that the gas fractions inferred from observations of star-forming galaxies at high-z are overestimated, owing to the adoption of locally-calibrated CO-H2 conversion factors (Xco). Evidence from both observations and numerical models suggest that Xco varies smoothly with the physical properties of galaxies, and that Xco can be parameterised simply as a function of both gas phase metallicity and observed CO surface bright"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1209.0771","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"},"aliases":[{"alias_kind":"arxiv","alias_value":"1209.0771","created_at":"2026-05-18T01:54:40.619677+00:00"},{"alias_kind":"arxiv_version","alias_value":"1209.0771v1","created_at":"2026-05-18T01:54:40.619677+00:00"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1209.0771","created_at":"2026-05-18T01:54:40.619677+00:00"},{"alias_kind":"pith_short_12","alias_value":"JNO224ID4HJ6","created_at":"2026-05-18T12:27:11.947152+00:00"},{"alias_kind":"pith_short_16","alias_value":"JNO224ID4HJ6MT2T","created_at":"2026-05-18T12:27:11.947152+00:00"},{"alias_kind":"pith_short_8","alias_value":"JNO224ID","created_at":"2026-05-18T12:27:11.947152+00:00"}],"events":[],"event_summary":{},"paper_claims":[],"inbound_citations":{"count":0,"internal_anchor_count":0,"sample":[]},"formal_canon":{"evidence_count":0,"sample":[],"anchors":[]},"links":{"html":"https://pith.science/pith/JNO224ID4HJ6MT2TR5LHX73FUD","json":"https://pith.science/pith/JNO224ID4HJ6MT2TR5LHX73FUD.json","graph_json":"https://pith.science/api/pith-number/JNO224ID4HJ6MT2TR5LHX73FUD/graph.json","events_json":"https://pith.science/api/pith-number/JNO224ID4HJ6MT2TR5LHX73FUD/events.json","paper":"https://pith.science/paper/JNO224ID"},"agent_actions":{"view_html":"https://pith.science/pith/JNO224ID4HJ6MT2TR5LHX73FUD","download_json":"https://pith.science/pith/JNO224ID4HJ6MT2TR5LHX73FUD.json","view_paper":"https://pith.science/paper/JNO224ID","resolve_alias":"https://pith.science/api/pith-number/resolve?arxiv=1209.0771&json=true","fetch_graph":"https://pith.science/api/pith-number/JNO224ID4HJ6MT2TR5LHX73FUD/graph.json","fetch_events":"https://pith.science/api/pith-number/JNO224ID4HJ6MT2TR5LHX73FUD/events.json","actions":{"anchor_timestamp":"https://pith.science/pith/JNO224ID4HJ6MT2TR5LHX73FUD/action/timestamp_anchor","attest_storage":"https://pith.science/pith/JNO224ID4HJ6MT2TR5LHX73FUD/action/storage_attestation","attest_author":"https://pith.science/pith/JNO224ID4HJ6MT2TR5LHX73FUD/action/author_attestation","sign_citation":"https://pith.science/pith/JNO224ID4HJ6MT2TR5LHX73FUD/action/citation_signature","submit_replication":"https://pith.science/pith/JNO224ID4HJ6MT2TR5LHX73FUD/action/replication_record"}},"created_at":"2026-05-18T01:54:40.619677+00:00","updated_at":"2026-05-18T01:54:40.619677+00:00"}