{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:OVGGYOK3Z6V7CH5ABHBQLMRANV","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":"80320c59a52690824119abb620259efcc686046653f1c13fafe44c269a6f01a4","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-10-05T18:01:20Z","title_canon_sha256":"36a0e755ceb0eda02aa74653f5cb2f46b9619a7b631fddf9f274cbe534798d34"},"schema_version":"1.0","source":{"id":"1810.02830","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1810.02830","created_at":"2026-05-18T00:01:27Z"},{"alias_kind":"arxiv_version","alias_value":"1810.02830v1","created_at":"2026-05-18T00:01:27Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1810.02830","created_at":"2026-05-18T00:01:27Z"},{"alias_kind":"pith_short_12","alias_value":"OVGGYOK3Z6V7","created_at":"2026-05-18T12:32:43Z"},{"alias_kind":"pith_short_16","alias_value":"OVGGYOK3Z6V7CH5A","created_at":"2026-05-18T12:32:43Z"},{"alias_kind":"pith_short_8","alias_value":"OVGGYOK3","created_at":"2026-05-18T12:32:43Z"}],"graph_snapshots":[{"event_id":"sha256:002c8bb57e00b4e5b366e506bcf90511ef79f1275284a16222f6dbb125ba1934","target":"graph","created_at":"2026-05-18T00:01:27Z","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 chemical abundances and radial velocities of six HII regions in the extremely metal-poor star-forming dwarf galaxy DDO 68. They are derived from deep spectra in the wavelength range 3500 - 10,000 {\\AA}, acquired with the Multi Object Double Spectrograph (MODS) at the Large Binocular Telescope (LBT). In the three regions where the [O III]$\\lambda$4363 {\\AA} line was detected, we inferred the abundance of He, N, O, Ne, Ar, and S through the \"direct\" method. We also derived the oxygen abundances of all the six regions adopting indirect method calibrations. We confirm that DDO 68 is an ","authors_text":"(2) Dipartimento di Fisica e Astronomia, (3) Space Telescope Science Institute, (4) INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica, A. Aloisi (3), A. Marchetti (4), Baltimore, Bologna, C. Nipoti (2), D. Romano (1), E. Sacchi (3) ((1) INAF-Osservatorio di Astrofisica e Scienza dello Spazio, F. Annibali (1), F. Cusano (1), Italy, Italy), L. Ciotti (2), M. Bellazzini (1), Milano, M. Mignoli (1), M. Tosi (1), Universit\\`a di Bologna, USA, V. La Torre (2)","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-10-05T18:01:20Z","title":"Chemical abundances and radial velocities in the extremely metal-poor galaxy DDO 68"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1810.02830","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":"sha256:2b3ad89a7a4aab63ada3edc8c56a32f8972adcc1e904bb4d17ebf0de5dc6b465","target":"record","created_at":"2026-05-18T00:01:27Z","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":"80320c59a52690824119abb620259efcc686046653f1c13fafe44c269a6f01a4","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-10-05T18:01:20Z","title_canon_sha256":"36a0e755ceb0eda02aa74653f5cb2f46b9619a7b631fddf9f274cbe534798d34"},"schema_version":"1.0","source":{"id":"1810.02830","kind":"arxiv","version":1}},"canonical_sha256":"754c6c395bcfabf11fa009c305b2206d7a4e306cc1e6e0b717b78bd37e037573","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"754c6c395bcfabf11fa009c305b2206d7a4e306cc1e6e0b717b78bd37e037573","first_computed_at":"2026-05-18T00:01:27.957270Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:01:27.957270Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"7FjyAS5DvNZADyDzrEMG9EhwwblZqwDUy1a1rjV67UbqacT7g8KYnCQgHGAO9mCcA04UdLUarlYywT1bcZBxAA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:01:27.957994Z","signed_message":"canonical_sha256_bytes"},"source_id":"1810.02830","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:2b3ad89a7a4aab63ada3edc8c56a32f8972adcc1e904bb4d17ebf0de5dc6b465","sha256:002c8bb57e00b4e5b366e506bcf90511ef79f1275284a16222f6dbb125ba1934"],"state_sha256":"06b797e4a202838a0fba051c2c181c8edae99e69d9735914690ac5c40750fe3e"}