{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2015:UL7MHOZWHBE5VJQ3E4SHOQ2M5O","short_pith_number":"pith:UL7MHOZW","canonical_record":{"source":{"id":"1507.00800","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2015-07-03T01:28:38Z","cross_cats_sorted":[],"title_canon_sha256":"67204cfd818cbb5befa64c1e81655a4a8083c8d75cd923e37a6a724bbf2c1f5f","abstract_canon_sha256":"41300c389fce6d98668093c81f24b1717a4bd23b274e16299009096cd3b8b1d2"},"schema_version":"1.0"},"canonical_sha256":"a2fec3bb363849daa61b272477434cebb4c1a8afcfc1e155588766321c69a59f","source":{"kind":"arxiv","id":"1507.00800","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1507.00800","created_at":"2026-05-18T01:35:07Z"},{"alias_kind":"arxiv_version","alias_value":"1507.00800v1","created_at":"2026-05-18T01:35:07Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1507.00800","created_at":"2026-05-18T01:35:07Z"},{"alias_kind":"pith_short_12","alias_value":"UL7MHOZWHBE5","created_at":"2026-05-18T12:29:44Z"},{"alias_kind":"pith_short_16","alias_value":"UL7MHOZWHBE5VJQ3","created_at":"2026-05-18T12:29:44Z"},{"alias_kind":"pith_short_8","alias_value":"UL7MHOZW","created_at":"2026-05-18T12:29:44Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2015:UL7MHOZWHBE5VJQ3E4SHOQ2M5O","target":"record","payload":{"canonical_record":{"source":{"id":"1507.00800","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2015-07-03T01:28:38Z","cross_cats_sorted":[],"title_canon_sha256":"67204cfd818cbb5befa64c1e81655a4a8083c8d75cd923e37a6a724bbf2c1f5f","abstract_canon_sha256":"41300c389fce6d98668093c81f24b1717a4bd23b274e16299009096cd3b8b1d2"},"schema_version":"1.0"},"canonical_sha256":"a2fec3bb363849daa61b272477434cebb4c1a8afcfc1e155588766321c69a59f","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:35:07.230716Z","signature_b64":"sTSH/08Qqq2GNvszjV/8cn62SSxgWff0ek5EeLdZyxgwexZFtqPtxKoSfyyngVK8m1DHVr53nOYxm5a7IPvcAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"a2fec3bb363849daa61b272477434cebb4c1a8afcfc1e155588766321c69a59f","last_reissued_at":"2026-05-18T01:35:07.230254Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:35:07.230254Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1507.00800","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":"2026-05-18T01:35:07Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"SPhTfDThlWc5GLkm6XZzpIsvMhUamA0/eUcfCqd/010crl5GBt64EQZ3eSKsS7FAdOKcUnkuI6RSnhXMyPgCDQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T23:47:09.760254Z"},"content_sha256":"ea702f50fa13fbd85faad5283051259f0fceb7cb90acae2f299e414ae7cfe2dd","schema_version":"1.0","event_id":"sha256:ea702f50fa13fbd85faad5283051259f0fceb7cb90acae2f299e414ae7cfe2dd"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2015:UL7MHOZWHBE5VJQ3E4SHOQ2M5O","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"A novel and sensitive method for measuring very weak magnetic fields of DA white dwarfs: A search for a magnetic field at the 250 G level in 40 Eri B","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.SR","authors_text":"A. J. Martin, D. Gadelshin, E. Semenko, G. Galazutdinov, G. G. Valyavin, J. D. Landstreet, S. Bagnulo","submitted_at":"2015-07-03T01:28:38Z","abstract_excerpt":"Searches for magnetic fields in white dwarfs have clarified both the frequency of occurrence and the global structure of the fields found down to field strengths of the order of 500 kG. Below this level, the situation is still very unclear. We are studying the weakest fields found in white dwarfs to determine the frequency of such fields and their structure. We describe a very sensitive new method of measuring such fields in DA (H-rich) white dwarfs, and search for a field in the brightest such star, 40 Eri B. Our new method makes use of the strongly enhanced polarisation signal in the sharp c"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1507.00800","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":"2026-05-18T01:35:07Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"xrbcbAIa+OMS1vWw/FYfOMaYn/xg7RL2+uHFMupQlfRZQHQs86c+m9DF/sbeSrpbYz6wzJlW2N6dy8mf0tNgDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T23:47:09.761037Z"},"content_sha256":"b7fbe147ee7ec983a5dc5d9bc5b8281d51f40a30357f1e61f315f0bfb525531c","schema_version":"1.0","event_id":"sha256:b7fbe147ee7ec983a5dc5d9bc5b8281d51f40a30357f1e61f315f0bfb525531c"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/UL7MHOZWHBE5VJQ3E4SHOQ2M5O/bundle.json","state_url":"https://pith.science/pith/UL7MHOZWHBE5VJQ3E4SHOQ2M5O/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/UL7MHOZWHBE5VJQ3E4SHOQ2M5O/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":"2026-05-25T23:47:09Z","links":{"resolver":"https://pith.science/pith/UL7MHOZWHBE5VJQ3E4SHOQ2M5O","bundle":"https://pith.science/pith/UL7MHOZWHBE5VJQ3E4SHOQ2M5O/bundle.json","state":"https://pith.science/pith/UL7MHOZWHBE5VJQ3E4SHOQ2M5O/state.json","well_known_bundle":"https://pith.science/.well-known/pith/UL7MHOZWHBE5VJQ3E4SHOQ2M5O/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2015:UL7MHOZWHBE5VJQ3E4SHOQ2M5O","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":"41300c389fce6d98668093c81f24b1717a4bd23b274e16299009096cd3b8b1d2","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2015-07-03T01:28:38Z","title_canon_sha256":"67204cfd818cbb5befa64c1e81655a4a8083c8d75cd923e37a6a724bbf2c1f5f"},"schema_version":"1.0","source":{"id":"1507.00800","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1507.00800","created_at":"2026-05-18T01:35:07Z"},{"alias_kind":"arxiv_version","alias_value":"1507.00800v1","created_at":"2026-05-18T01:35:07Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1507.00800","created_at":"2026-05-18T01:35:07Z"},{"alias_kind":"pith_short_12","alias_value":"UL7MHOZWHBE5","created_at":"2026-05-18T12:29:44Z"},{"alias_kind":"pith_short_16","alias_value":"UL7MHOZWHBE5VJQ3","created_at":"2026-05-18T12:29:44Z"},{"alias_kind":"pith_short_8","alias_value":"UL7MHOZW","created_at":"2026-05-18T12:29:44Z"}],"graph_snapshots":[{"event_id":"sha256:b7fbe147ee7ec983a5dc5d9bc5b8281d51f40a30357f1e61f315f0bfb525531c","target":"graph","created_at":"2026-05-18T01:35:07Z","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":"Searches for magnetic fields in white dwarfs have clarified both the frequency of occurrence and the global structure of the fields found down to field strengths of the order of 500 kG. Below this level, the situation is still very unclear. We are studying the weakest fields found in white dwarfs to determine the frequency of such fields and their structure. We describe a very sensitive new method of measuring such fields in DA (H-rich) white dwarfs, and search for a field in the brightest such star, 40 Eri B. Our new method makes use of the strongly enhanced polarisation signal in the sharp c","authors_text":"A. J. Martin, D. Gadelshin, E. Semenko, G. Galazutdinov, G. G. Valyavin, J. D. Landstreet, S. Bagnulo","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2015-07-03T01:28:38Z","title":"A novel and sensitive method for measuring very weak magnetic fields of DA white dwarfs: A search for a magnetic field at the 250 G level in 40 Eri B"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1507.00800","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:ea702f50fa13fbd85faad5283051259f0fceb7cb90acae2f299e414ae7cfe2dd","target":"record","created_at":"2026-05-18T01:35:07Z","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":"41300c389fce6d98668093c81f24b1717a4bd23b274e16299009096cd3b8b1d2","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2015-07-03T01:28:38Z","title_canon_sha256":"67204cfd818cbb5befa64c1e81655a4a8083c8d75cd923e37a6a724bbf2c1f5f"},"schema_version":"1.0","source":{"id":"1507.00800","kind":"arxiv","version":1}},"canonical_sha256":"a2fec3bb363849daa61b272477434cebb4c1a8afcfc1e155588766321c69a59f","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"a2fec3bb363849daa61b272477434cebb4c1a8afcfc1e155588766321c69a59f","first_computed_at":"2026-05-18T01:35:07.230254Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:35:07.230254Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"sTSH/08Qqq2GNvszjV/8cn62SSxgWff0ek5EeLdZyxgwexZFtqPtxKoSfyyngVK8m1DHVr53nOYxm5a7IPvcAA==","signature_status":"signed_v1","signed_at":"2026-05-18T01:35:07.230716Z","signed_message":"canonical_sha256_bytes"},"source_id":"1507.00800","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:ea702f50fa13fbd85faad5283051259f0fceb7cb90acae2f299e414ae7cfe2dd","sha256:b7fbe147ee7ec983a5dc5d9bc5b8281d51f40a30357f1e61f315f0bfb525531c"],"state_sha256":"5df8c4fc58539dd57f42d0dd897b8b49c899e30c55526946977261f869021751"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"L2EM9LOHTkDBd6+sm9Jiqtm1TOVeiZ2b5LwqPDMrtXuhkWVt9SYclRB6fMr1CSvDvCbxUuX2AFvA+QYidwMSBQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-25T23:47:09.765150Z","bundle_sha256":"8210dac79cc5a53f062f068b6742276547bb7a0fdd3123a360b043457e1ac809"}}