{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2012:UEQ76SJYV3DFOLTDFIOOFB2Y2K","short_pith_number":"pith:UEQ76SJY","canonical_record":{"source":{"id":"1208.4478","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2012-08-22T11:25:09Z","cross_cats_sorted":[],"title_canon_sha256":"2ca0c91408641e2133b510cbad0d33851db9018eae0a26630d1ecd46915bbfc3","abstract_canon_sha256":"79e9ff68cb71ced23ee7ebf60787447df1caf8fb174fa9a37620a53a48dba90b"},"schema_version":"1.0"},"canonical_sha256":"a121ff4938aec6572e632a1ce28758d2b73ffe83d4d143b4e630b73e3d52db79","source":{"kind":"arxiv","id":"1208.4478","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1208.4478","created_at":"2026-05-18T01:54:59Z"},{"alias_kind":"arxiv_version","alias_value":"1208.4478v1","created_at":"2026-05-18T01:54:59Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1208.4478","created_at":"2026-05-18T01:54:59Z"},{"alias_kind":"pith_short_12","alias_value":"UEQ76SJYV3DF","created_at":"2026-05-18T12:27:23Z"},{"alias_kind":"pith_short_16","alias_value":"UEQ76SJYV3DFOLTD","created_at":"2026-05-18T12:27:23Z"},{"alias_kind":"pith_short_8","alias_value":"UEQ76SJY","created_at":"2026-05-18T12:27:23Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2012:UEQ76SJYV3DFOLTDFIOOFB2Y2K","target":"record","payload":{"canonical_record":{"source":{"id":"1208.4478","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2012-08-22T11:25:09Z","cross_cats_sorted":[],"title_canon_sha256":"2ca0c91408641e2133b510cbad0d33851db9018eae0a26630d1ecd46915bbfc3","abstract_canon_sha256":"79e9ff68cb71ced23ee7ebf60787447df1caf8fb174fa9a37620a53a48dba90b"},"schema_version":"1.0"},"canonical_sha256":"a121ff4938aec6572e632a1ce28758d2b73ffe83d4d143b4e630b73e3d52db79","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:54:59.755701Z","signature_b64":"DYMplxeQxKhLU1RYWIwcF9FZlSnAReRN0N+8zFIQ9rYDUK/KkxjniyOczIm/4sE7hBpz0MBqlLk+MpSMMOGTAw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"a121ff4938aec6572e632a1ce28758d2b73ffe83d4d143b4e630b73e3d52db79","last_reissued_at":"2026-05-18T01:54:59.755023Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:54:59.755023Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1208.4478","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":"2026-05-18T01:54:59Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"OT1LX4bzwS+S4CQooN+K+bsQop5uV0mhPCr+K9hhTLwfTn8WgqromF+Rakae46Wq4mWRSy7/EM+CbWG7E8/7Cw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-02T19:25:06.556557Z"},"content_sha256":"05ece9ac214aa7854392ca83fbd3d574b1d6fbd5c2fb24d7fa6e7a285a22bb94","schema_version":"1.0","event_id":"sha256:05ece9ac214aa7854392ca83fbd3d574b1d6fbd5c2fb24d7fa6e7a285a22bb94"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2012:UEQ76SJYV3DFOLTDFIOOFB2Y2K","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Chandra grating spectroscopy of three hot white dwarfs","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.SR","authors_text":"J. Adamczak, J. J. Drake, J. W. Kruk, K. Werner, S. Schuh, T. Rauch","submitted_at":"2012-08-22T11:25:09Z","abstract_excerpt":"High-resolution soft X-ray spectroscopic observations of single hot white dwarfs are scarce. With the Chandra Low-Energy Transmission Grating, we have observed two white dwarfs, one is of spectral type DA (LB 1919) and the other is a non-DA of spectral type PG1159 (PG 1520+525). The spectra of both stars are analyzed, together with an archival Chandra spectrum of another DA white dwarf (GD 246). The soft X-ray spectra of the two DA white dwarfs are investigated in order to study the effect of gravitational settling and radiative levitation of metals in their photospheres. LB 1919 is of interes"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1208.4478","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":"2026-05-18T01:54:59Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"TxjWWr7HtZ6+4JUAuqjVP9Xf1v2/crbbzsrUKsxBk3Yln925WiLJk1Wq96xEh4or3OMbsGE8N22VL9tfnVKSDA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-02T19:25:06.556895Z"},"content_sha256":"4515e3b7024a760fe2c21b32e1431436d278b3f848fb842da50561e836861e22","schema_version":"1.0","event_id":"sha256:4515e3b7024a760fe2c21b32e1431436d278b3f848fb842da50561e836861e22"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/UEQ76SJYV3DFOLTDFIOOFB2Y2K/bundle.json","state_url":"https://pith.science/pith/UEQ76SJYV3DFOLTDFIOOFB2Y2K/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/UEQ76SJYV3DFOLTDFIOOFB2Y2K/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":"2026-06-02T19:25:06Z","links":{"resolver":"https://pith.science/pith/UEQ76SJYV3DFOLTDFIOOFB2Y2K","bundle":"https://pith.science/pith/UEQ76SJYV3DFOLTDFIOOFB2Y2K/bundle.json","state":"https://pith.science/pith/UEQ76SJYV3DFOLTDFIOOFB2Y2K/state.json","well_known_bundle":"https://pith.science/.well-known/pith/UEQ76SJYV3DFOLTDFIOOFB2Y2K/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2012:UEQ76SJYV3DFOLTDFIOOFB2Y2K","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":"79e9ff68cb71ced23ee7ebf60787447df1caf8fb174fa9a37620a53a48dba90b","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2012-08-22T11:25:09Z","title_canon_sha256":"2ca0c91408641e2133b510cbad0d33851db9018eae0a26630d1ecd46915bbfc3"},"schema_version":"1.0","source":{"id":"1208.4478","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1208.4478","created_at":"2026-05-18T01:54:59Z"},{"alias_kind":"arxiv_version","alias_value":"1208.4478v1","created_at":"2026-05-18T01:54:59Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1208.4478","created_at":"2026-05-18T01:54:59Z"},{"alias_kind":"pith_short_12","alias_value":"UEQ76SJYV3DF","created_at":"2026-05-18T12:27:23Z"},{"alias_kind":"pith_short_16","alias_value":"UEQ76SJYV3DFOLTD","created_at":"2026-05-18T12:27:23Z"},{"alias_kind":"pith_short_8","alias_value":"UEQ76SJY","created_at":"2026-05-18T12:27:23Z"}],"graph_snapshots":[{"event_id":"sha256:4515e3b7024a760fe2c21b32e1431436d278b3f848fb842da50561e836861e22","target":"graph","created_at":"2026-05-18T01:54:59Z","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":"High-resolution soft X-ray spectroscopic observations of single hot white dwarfs are scarce. With the Chandra Low-Energy Transmission Grating, we have observed two white dwarfs, one is of spectral type DA (LB 1919) and the other is a non-DA of spectral type PG1159 (PG 1520+525). The spectra of both stars are analyzed, together with an archival Chandra spectrum of another DA white dwarf (GD 246). The soft X-ray spectra of the two DA white dwarfs are investigated in order to study the effect of gravitational settling and radiative levitation of metals in their photospheres. LB 1919 is of interes","authors_text":"J. Adamczak, J. J. Drake, J. W. Kruk, K. Werner, S. Schuh, T. Rauch","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2012-08-22T11:25:09Z","title":"Chandra grating spectroscopy of three hot white dwarfs"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1208.4478","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":"sha256:05ece9ac214aa7854392ca83fbd3d574b1d6fbd5c2fb24d7fa6e7a285a22bb94","target":"record","created_at":"2026-05-18T01:54:59Z","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":"79e9ff68cb71ced23ee7ebf60787447df1caf8fb174fa9a37620a53a48dba90b","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2012-08-22T11:25:09Z","title_canon_sha256":"2ca0c91408641e2133b510cbad0d33851db9018eae0a26630d1ecd46915bbfc3"},"schema_version":"1.0","source":{"id":"1208.4478","kind":"arxiv","version":1}},"canonical_sha256":"a121ff4938aec6572e632a1ce28758d2b73ffe83d4d143b4e630b73e3d52db79","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"a121ff4938aec6572e632a1ce28758d2b73ffe83d4d143b4e630b73e3d52db79","first_computed_at":"2026-05-18T01:54:59.755023Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:54:59.755023Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"DYMplxeQxKhLU1RYWIwcF9FZlSnAReRN0N+8zFIQ9rYDUK/KkxjniyOczIm/4sE7hBpz0MBqlLk+MpSMMOGTAw==","signature_status":"signed_v1","signed_at":"2026-05-18T01:54:59.755701Z","signed_message":"canonical_sha256_bytes"},"source_id":"1208.4478","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:05ece9ac214aa7854392ca83fbd3d574b1d6fbd5c2fb24d7fa6e7a285a22bb94","sha256:4515e3b7024a760fe2c21b32e1431436d278b3f848fb842da50561e836861e22"],"state_sha256":"ad95a737e58d19b475973bbd7dcd4eca24ea7a401c2789e8cf68cf000e6b26ba"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"P88JnaXDGxCjYAnVAtCErO2UwGuX+rfvu7I+9KZJZ5l/I6Eqfdt9M0gC9mZs70j80z0l2h+14uOy5j3E11eUDg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-02T19:25:06.558899Z","bundle_sha256":"ea3413e60027c870c2c292058bd300048c39b9a0f9a3e0ff692406391ffd843e"}}