{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:SJY3MP5G62WAIKJAJGR2VHUFYV","short_pith_number":"pith:SJY3MP5G","canonical_record":{"source":{"id":"1804.06856","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-04-18T18:00:06Z","cross_cats_sorted":[],"title_canon_sha256":"efbd2920a9f1ef137e85fe71f0db1b6c603707ae6614a511ebe91f43bbfe7b41","abstract_canon_sha256":"5662207178412fc3846a5621d851110b1ba4c78216d4797f16bf7a2c1836558f"},"schema_version":"1.0"},"canonical_sha256":"9271b63fa6f6ac04292049a3aa9e85c57438bb793a43150ad33cdfd63266a870","source":{"kind":"arxiv","id":"1804.06856","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1804.06856","created_at":"2026-05-18T00:08:42Z"},{"alias_kind":"arxiv_version","alias_value":"1804.06856v2","created_at":"2026-05-18T00:08:42Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1804.06856","created_at":"2026-05-18T00:08:42Z"},{"alias_kind":"pith_short_12","alias_value":"SJY3MP5G62WA","created_at":"2026-05-18T12:32:53Z"},{"alias_kind":"pith_short_16","alias_value":"SJY3MP5G62WAIKJA","created_at":"2026-05-18T12:32:53Z"},{"alias_kind":"pith_short_8","alias_value":"SJY3MP5G","created_at":"2026-05-18T12:32:53Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:SJY3MP5G62WAIKJAJGR2VHUFYV","target":"record","payload":{"canonical_record":{"source":{"id":"1804.06856","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-04-18T18:00:06Z","cross_cats_sorted":[],"title_canon_sha256":"efbd2920a9f1ef137e85fe71f0db1b6c603707ae6614a511ebe91f43bbfe7b41","abstract_canon_sha256":"5662207178412fc3846a5621d851110b1ba4c78216d4797f16bf7a2c1836558f"},"schema_version":"1.0"},"canonical_sha256":"9271b63fa6f6ac04292049a3aa9e85c57438bb793a43150ad33cdfd63266a870","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:08:42.276291Z","signature_b64":"7cp8QO88ggfe7IozqUzyF32uYSGkt26iVA5yZLlryxyuomIVotOCYJt1/nPDzcluaSRoCQMAuSpx2M1hhzU0DA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"9271b63fa6f6ac04292049a3aa9e85c57438bb793a43150ad33cdfd63266a870","last_reissued_at":"2026-05-18T00:08:42.275632Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:08:42.275632Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1804.06856","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T00:08:42Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"vvVlFWC2BntGZtgak2rMWvgj/PWpHP6I3CNnldqya4R/SFtp+4xScJDI6y+1c+0IdwvvjnqJJYjBJftZY5XXDQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T17:53:10.811155Z"},"content_sha256":"ad9a911f29867048c0b5df3ac96120f1bd371df2812f70c90c6f7760c19ffd7b","schema_version":"1.0","event_id":"sha256:ad9a911f29867048c0b5df3ac96120f1bd371df2812f70c90c6f7760c19ffd7b"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:SJY3MP5G62WAIKJAJGR2VHUFYV","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Estimating stellar birth radii and the time evolution of the Milky Way's ISM metallicity gradient","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"A. Queiroz, A. Recio-Blanco, B. X. Santiago, C. Chiappini, F. Anders, G. Cescutti, G. Guiglion, G. Kordopatis, I. Carrillo, I. Minchev, M. Hayden, M. Martig, M. Steinmetz, P. de Laverny, R. S. de Jong, S. R. Majewski, V. Adibekyan","submitted_at":"2018-04-18T18:00:06Z","abstract_excerpt":"We present a semi-empirical, largely model-independent approach for estimating Galactic birth radii, r_birth, for Milky Way disk stars. The technique relies on the justifiable assumption that a negative radial metallicity gradient in the interstellar medium (ISM) existed for most of the disk lifetime. Stars are projected back to their birth positions according to the observationally derived age and [Fe/H] with no kinematical information required. Applying our approach to the AMBRE:HARPS and HARPS-GTO local samples, we show that we can constrain the ISM metallicity evolution with Galactic radiu"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1804.06856","kind":"arxiv","version":2},"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":"2026-05-18T00:08:42Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"yDeSb5Dw7naBfApPpyspgFAbunL9kOcMNqy18g407jNlNBCka+r4LRymHMtnJgdHEU1wJg7F74Gvm2cjPyJ5CA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-28T17:53:10.811839Z"},"content_sha256":"9df422455844523b6fbc11cf04a6cba90cf288b70de2aa9bbd3fba53868a875f","schema_version":"1.0","event_id":"sha256:9df422455844523b6fbc11cf04a6cba90cf288b70de2aa9bbd3fba53868a875f"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/SJY3MP5G62WAIKJAJGR2VHUFYV/bundle.json","state_url":"https://pith.science/pith/SJY3MP5G62WAIKJAJGR2VHUFYV/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/SJY3MP5G62WAIKJAJGR2VHUFYV/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":"2026-05-28T17:53:10Z","links":{"resolver":"https://pith.science/pith/SJY3MP5G62WAIKJAJGR2VHUFYV","bundle":"https://pith.science/pith/SJY3MP5G62WAIKJAJGR2VHUFYV/bundle.json","state":"https://pith.science/pith/SJY3MP5G62WAIKJAJGR2VHUFYV/state.json","well_known_bundle":"https://pith.science/.well-known/pith/SJY3MP5G62WAIKJAJGR2VHUFYV/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:SJY3MP5G62WAIKJAJGR2VHUFYV","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":"5662207178412fc3846a5621d851110b1ba4c78216d4797f16bf7a2c1836558f","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-04-18T18:00:06Z","title_canon_sha256":"efbd2920a9f1ef137e85fe71f0db1b6c603707ae6614a511ebe91f43bbfe7b41"},"schema_version":"1.0","source":{"id":"1804.06856","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1804.06856","created_at":"2026-05-18T00:08:42Z"},{"alias_kind":"arxiv_version","alias_value":"1804.06856v2","created_at":"2026-05-18T00:08:42Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1804.06856","created_at":"2026-05-18T00:08:42Z"},{"alias_kind":"pith_short_12","alias_value":"SJY3MP5G62WA","created_at":"2026-05-18T12:32:53Z"},{"alias_kind":"pith_short_16","alias_value":"SJY3MP5G62WAIKJA","created_at":"2026-05-18T12:32:53Z"},{"alias_kind":"pith_short_8","alias_value":"SJY3MP5G","created_at":"2026-05-18T12:32:53Z"}],"graph_snapshots":[{"event_id":"sha256:9df422455844523b6fbc11cf04a6cba90cf288b70de2aa9bbd3fba53868a875f","target":"graph","created_at":"2026-05-18T00:08:42Z","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 a semi-empirical, largely model-independent approach for estimating Galactic birth radii, r_birth, for Milky Way disk stars. The technique relies on the justifiable assumption that a negative radial metallicity gradient in the interstellar medium (ISM) existed for most of the disk lifetime. Stars are projected back to their birth positions according to the observationally derived age and [Fe/H] with no kinematical information required. Applying our approach to the AMBRE:HARPS and HARPS-GTO local samples, we show that we can constrain the ISM metallicity evolution with Galactic radiu","authors_text":"A. Queiroz, A. Recio-Blanco, B. X. Santiago, C. Chiappini, F. Anders, G. Cescutti, G. Guiglion, G. Kordopatis, I. Carrillo, I. Minchev, M. Hayden, M. Martig, M. Steinmetz, P. de Laverny, R. S. de Jong, S. R. Majewski, V. Adibekyan","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-04-18T18:00:06Z","title":"Estimating stellar birth radii and the time evolution of the Milky Way's ISM metallicity gradient"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1804.06856","kind":"arxiv","version":2},"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:ad9a911f29867048c0b5df3ac96120f1bd371df2812f70c90c6f7760c19ffd7b","target":"record","created_at":"2026-05-18T00:08:42Z","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":"5662207178412fc3846a5621d851110b1ba4c78216d4797f16bf7a2c1836558f","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-04-18T18:00:06Z","title_canon_sha256":"efbd2920a9f1ef137e85fe71f0db1b6c603707ae6614a511ebe91f43bbfe7b41"},"schema_version":"1.0","source":{"id":"1804.06856","kind":"arxiv","version":2}},"canonical_sha256":"9271b63fa6f6ac04292049a3aa9e85c57438bb793a43150ad33cdfd63266a870","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"9271b63fa6f6ac04292049a3aa9e85c57438bb793a43150ad33cdfd63266a870","first_computed_at":"2026-05-18T00:08:42.275632Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:08:42.275632Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"7cp8QO88ggfe7IozqUzyF32uYSGkt26iVA5yZLlryxyuomIVotOCYJt1/nPDzcluaSRoCQMAuSpx2M1hhzU0DA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:08:42.276291Z","signed_message":"canonical_sha256_bytes"},"source_id":"1804.06856","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:ad9a911f29867048c0b5df3ac96120f1bd371df2812f70c90c6f7760c19ffd7b","sha256:9df422455844523b6fbc11cf04a6cba90cf288b70de2aa9bbd3fba53868a875f"],"state_sha256":"a7efb4169647b8310ea3fd68b1aaa6393f51d09b9f9844d7f0f6b28586f28798"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"kbUl8K1IHwmbbCO6D8rEd8fMBOO9RYUNorTENrSIGsPv0GmFNIDo/hg8oVTJ1jn2GrwpTWne1waORH1iNm6IAg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-28T17:53:10.814939Z","bundle_sha256":"cc2a16f6404130e08351a60119205c0fedf0332bec8471580821cf52e943b07c"}}