{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:7MVHRXTL7NGBXZA2EGMC3Y4Y5Y","short_pith_number":"pith:7MVHRXTL","canonical_record":{"source":{"id":"1901.08068","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-01-23T19:00:01Z","cross_cats_sorted":[],"title_canon_sha256":"ced2c251443d2280150e49f35f452c7111ddd55ef47533d290d18ab5f24a4551","abstract_canon_sha256":"9b6ae8c8db1c1e33d86cc40f7fce9bd2ff278013bb9cd52802743254ee982fb4"},"schema_version":"1.0"},"canonical_sha256":"fb2a78de6bfb4c1be41a21982de398ee25e749f75ebc1314a5adb43e275bf693","source":{"kind":"arxiv","id":"1901.08068","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1901.08068","created_at":"2026-05-17T23:55:10Z"},{"alias_kind":"arxiv_version","alias_value":"1901.08068v1","created_at":"2026-05-17T23:55:10Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1901.08068","created_at":"2026-05-17T23:55:10Z"},{"alias_kind":"pith_short_12","alias_value":"7MVHRXTL7NGB","created_at":"2026-05-18T12:33:12Z"},{"alias_kind":"pith_short_16","alias_value":"7MVHRXTL7NGBXZA2","created_at":"2026-05-18T12:33:12Z"},{"alias_kind":"pith_short_8","alias_value":"7MVHRXTL","created_at":"2026-05-18T12:33:12Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:7MVHRXTL7NGBXZA2EGMC3Y4Y5Y","target":"record","payload":{"canonical_record":{"source":{"id":"1901.08068","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-01-23T19:00:01Z","cross_cats_sorted":[],"title_canon_sha256":"ced2c251443d2280150e49f35f452c7111ddd55ef47533d290d18ab5f24a4551","abstract_canon_sha256":"9b6ae8c8db1c1e33d86cc40f7fce9bd2ff278013bb9cd52802743254ee982fb4"},"schema_version":"1.0"},"canonical_sha256":"fb2a78de6bfb4c1be41a21982de398ee25e749f75ebc1314a5adb43e275bf693","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:55:10.181229Z","signature_b64":"5YxU/2uUfrKXsgFNZt7Z+MtkpPUOJjiJkWQtHTbIo0dUgWA7mgwXh2WJZ1JDuru3YEqN6EH2U8Iwq2MUWVppDA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"fb2a78de6bfb4c1be41a21982de398ee25e749f75ebc1314a5adb43e275bf693","last_reissued_at":"2026-05-17T23:55:10.180785Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:55:10.180785Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1901.08068","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":"2026-05-17T23:55:10Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"AkG5Xp1P+L56wCnRZXJ2v5kdGVKZ7f+CeZCSo4wpptkbvx2QmZFsiqX2stljLCypYkozuwhYgCHifd2XGp/VBg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-05T07:01:32.527724Z"},"content_sha256":"b06223d36944df426b70e6da697be8f16f996413ba81205cac0750803935cd60","schema_version":"1.0","event_id":"sha256:b06223d36944df426b70e6da697be8f16f996413ba81205cac0750803935cd60"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:7MVHRXTL7NGBXZA2EGMC3Y4Y5Y","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Extreme chemical abundance ratio suggesting an exotic origin for an ultra-diffuse galaxy","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Aaron J. Romanowsky, Adebusola Alabi, Alexa Villaume, Anna Ferre-Mateu, David Martinez-Delgado, Duncan A. Forbes, Ignacio Martin-Navarro, Jean P. Brodie, Margarita Sharina, Viraj Pandya","submitted_at":"2019-01-23T19:00:01Z","abstract_excerpt":"Ultra diffuse galaxies are a population of extended galaxies but with relatively low luminosities. The origin of these objects remains unclear, largely due to the observational challenges of the low surface brightness Universe. We present here a detailed stellar population analysis of a relatively isolated UDG, DGSAT I, based on spectroscopic data from the Keck Cosmic Web Imager integral field unit. The star formation history of DGSAT I seems to be extended, with a mean luminosity-weighted age of ~3 Gyr, in agreement with previous photometric studies. However, we find a very high [Mg/Fe] abund"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1901.08068","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":"2026-05-17T23:55:10Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ZeLDr2rLa+0cx8UiASEGS7BDOOmipSvalo64l9WtEDZigttFKLIOifkX7KXGyGhQFoqeXvoB+5buQ7IWQvWQBg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-05T07:01:32.528433Z"},"content_sha256":"4ea3ffdceb76420237bde3d246f06839cf704fd4f887672e5fd31251fea6bf68","schema_version":"1.0","event_id":"sha256:4ea3ffdceb76420237bde3d246f06839cf704fd4f887672e5fd31251fea6bf68"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/7MVHRXTL7NGBXZA2EGMC3Y4Y5Y/bundle.json","state_url":"https://pith.science/pith/7MVHRXTL7NGBXZA2EGMC3Y4Y5Y/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/7MVHRXTL7NGBXZA2EGMC3Y4Y5Y/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":"2026-06-05T07:01:32Z","links":{"resolver":"https://pith.science/pith/7MVHRXTL7NGBXZA2EGMC3Y4Y5Y","bundle":"https://pith.science/pith/7MVHRXTL7NGBXZA2EGMC3Y4Y5Y/bundle.json","state":"https://pith.science/pith/7MVHRXTL7NGBXZA2EGMC3Y4Y5Y/state.json","well_known_bundle":"https://pith.science/.well-known/pith/7MVHRXTL7NGBXZA2EGMC3Y4Y5Y/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:7MVHRXTL7NGBXZA2EGMC3Y4Y5Y","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":"9b6ae8c8db1c1e33d86cc40f7fce9bd2ff278013bb9cd52802743254ee982fb4","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-01-23T19:00:01Z","title_canon_sha256":"ced2c251443d2280150e49f35f452c7111ddd55ef47533d290d18ab5f24a4551"},"schema_version":"1.0","source":{"id":"1901.08068","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1901.08068","created_at":"2026-05-17T23:55:10Z"},{"alias_kind":"arxiv_version","alias_value":"1901.08068v1","created_at":"2026-05-17T23:55:10Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1901.08068","created_at":"2026-05-17T23:55:10Z"},{"alias_kind":"pith_short_12","alias_value":"7MVHRXTL7NGB","created_at":"2026-05-18T12:33:12Z"},{"alias_kind":"pith_short_16","alias_value":"7MVHRXTL7NGBXZA2","created_at":"2026-05-18T12:33:12Z"},{"alias_kind":"pith_short_8","alias_value":"7MVHRXTL","created_at":"2026-05-18T12:33:12Z"}],"graph_snapshots":[{"event_id":"sha256:4ea3ffdceb76420237bde3d246f06839cf704fd4f887672e5fd31251fea6bf68","target":"graph","created_at":"2026-05-17T23:55:10Z","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":"Ultra diffuse galaxies are a population of extended galaxies but with relatively low luminosities. The origin of these objects remains unclear, largely due to the observational challenges of the low surface brightness Universe. We present here a detailed stellar population analysis of a relatively isolated UDG, DGSAT I, based on spectroscopic data from the Keck Cosmic Web Imager integral field unit. The star formation history of DGSAT I seems to be extended, with a mean luminosity-weighted age of ~3 Gyr, in agreement with previous photometric studies. However, we find a very high [Mg/Fe] abund","authors_text":"Aaron J. Romanowsky, Adebusola Alabi, Alexa Villaume, Anna Ferre-Mateu, David Martinez-Delgado, Duncan A. Forbes, Ignacio Martin-Navarro, Jean P. Brodie, Margarita Sharina, Viraj Pandya","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-01-23T19:00:01Z","title":"Extreme chemical abundance ratio suggesting an exotic origin for an ultra-diffuse galaxy"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1901.08068","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:b06223d36944df426b70e6da697be8f16f996413ba81205cac0750803935cd60","target":"record","created_at":"2026-05-17T23:55:10Z","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":"9b6ae8c8db1c1e33d86cc40f7fce9bd2ff278013bb9cd52802743254ee982fb4","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2019-01-23T19:00:01Z","title_canon_sha256":"ced2c251443d2280150e49f35f452c7111ddd55ef47533d290d18ab5f24a4551"},"schema_version":"1.0","source":{"id":"1901.08068","kind":"arxiv","version":1}},"canonical_sha256":"fb2a78de6bfb4c1be41a21982de398ee25e749f75ebc1314a5adb43e275bf693","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"fb2a78de6bfb4c1be41a21982de398ee25e749f75ebc1314a5adb43e275bf693","first_computed_at":"2026-05-17T23:55:10.180785Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:55:10.180785Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"5YxU/2uUfrKXsgFNZt7Z+MtkpPUOJjiJkWQtHTbIo0dUgWA7mgwXh2WJZ1JDuru3YEqN6EH2U8Iwq2MUWVppDA==","signature_status":"signed_v1","signed_at":"2026-05-17T23:55:10.181229Z","signed_message":"canonical_sha256_bytes"},"source_id":"1901.08068","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:b06223d36944df426b70e6da697be8f16f996413ba81205cac0750803935cd60","sha256:4ea3ffdceb76420237bde3d246f06839cf704fd4f887672e5fd31251fea6bf68"],"state_sha256":"d25b3aa86d0eb72cd04e87af2eea46b811bde0e8468c644fc761dfade5e5c9a7"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"8GNA3xqts25Pz8SESFZDrBPt+FcaBQU6cIGrZ9yOc6bkLYhJsH0VtzaCgxdxR0oiFdrd5paLqrVbqWEntg8SDA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-05T07:01:32.532157Z","bundle_sha256":"916a997c9e2a3653df7c5c16b4e75e498fa3a4a4c72e9ff832c8706cffb7280d"}}