{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:WTBFOPKRS2JYPRDVXJBM55PJNM","short_pith_number":"pith:WTBFOPKR","canonical_record":{"source":{"id":"1805.02221","kind":"arxiv","version":3},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.plasm-ph","submitted_at":"2018-05-06T14:30:14Z","cross_cats_sorted":[],"title_canon_sha256":"0f4f47fbf61e1e44810e7efe4583e500d83f00759c750fd7817630a2930b1f4f","abstract_canon_sha256":"3de852675b230e25b72b0f6a6901461dda6f11723db87488068703ce16754dfe"},"schema_version":"1.0"},"canonical_sha256":"b4c2573d51969387c475ba42cef5e96b0b0489dc25d47aa4c26a4a6f5114f2ab","source":{"kind":"arxiv","id":"1805.02221","version":3},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1805.02221","created_at":"2026-05-18T00:03:16Z"},{"alias_kind":"arxiv_version","alias_value":"1805.02221v3","created_at":"2026-05-18T00:03:16Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1805.02221","created_at":"2026-05-18T00:03:16Z"},{"alias_kind":"pith_short_12","alias_value":"WTBFOPKRS2JY","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_16","alias_value":"WTBFOPKRS2JYPRDV","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_8","alias_value":"WTBFOPKR","created_at":"2026-05-18T12:33:01Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:WTBFOPKRS2JYPRDVXJBM55PJNM","target":"record","payload":{"canonical_record":{"source":{"id":"1805.02221","kind":"arxiv","version":3},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.plasm-ph","submitted_at":"2018-05-06T14:30:14Z","cross_cats_sorted":[],"title_canon_sha256":"0f4f47fbf61e1e44810e7efe4583e500d83f00759c750fd7817630a2930b1f4f","abstract_canon_sha256":"3de852675b230e25b72b0f6a6901461dda6f11723db87488068703ce16754dfe"},"schema_version":"1.0"},"canonical_sha256":"b4c2573d51969387c475ba42cef5e96b0b0489dc25d47aa4c26a4a6f5114f2ab","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:03:16.663386Z","signature_b64":"49OpoToRcLkMJjIWm6H0roqKhlG3rlQW3S64ooVmMCcH83yyCV43VGWr2lfXegnhCJMbLoDi3gqj2jeGLkAuBA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"b4c2573d51969387c475ba42cef5e96b0b0489dc25d47aa4c26a4a6f5114f2ab","last_reissued_at":"2026-05-18T00:03:16.662876Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:03:16.662876Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1805.02221","source_version":3,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T00:03:16Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"lqwJYO/m5O2k/sLH2Hxf6uWUommyWR9lfg+LDAION3ic5WbmGE8APv1S3PkuUDyFdc16vfqVKl2eImkKIaspDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T11:43:44.808249Z"},"content_sha256":"ef3336a109695a679049c6ad5919952b407af0e7eb7dd1c6f589dde87b97549d","schema_version":"1.0","event_id":"sha256:ef3336a109695a679049c6ad5919952b407af0e7eb7dd1c6f589dde87b97549d"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:WTBFOPKRS2JYPRDVXJBM55PJNM","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Non-planar elasticae as optimal curves for the magnetic axis of stellarators","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"physics.plasm-ph","authors_text":"David Pfefferl\\'e, Lee Gunderson, Lyle Noakes, Stuart R. Hudson","submitted_at":"2018-05-06T14:30:14Z","abstract_excerpt":"The problem of finding an optimal curve for the target magnetic axis of a stellarator is addressed. Euler-Lagrange equations are derived for finite length three-dimensional curves that extremise their bending energy while yielding fixed integrated torsion. The obvious translational and rotational symmetry is exploited to express solutions in a preferred cylindrical coordinate system in terms of elliptic Jacobi functions. These solution curves, which, up to similarity transformations, depend on three dimensionless parameters, do not necessarily close. Two closure conditions are obtained for the"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1805.02221","kind":"arxiv","version":3},"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":"2026-05-18T00:03:16Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"9X1xFj+SCCbIVE8I/n7bkfJw99jJA2hp1JQut8yruGgBXcNVQC81/wRO6YiXqrY+0Cujc9wQiS9+Vux/T1WUBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T11:43:44.808955Z"},"content_sha256":"dc90236d818f177ee0708f0c98b6ea21da3bc37c848f2a2578b56147745c69c6","schema_version":"1.0","event_id":"sha256:dc90236d818f177ee0708f0c98b6ea21da3bc37c848f2a2578b56147745c69c6"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/WTBFOPKRS2JYPRDVXJBM55PJNM/bundle.json","state_url":"https://pith.science/pith/WTBFOPKRS2JYPRDVXJBM55PJNM/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/WTBFOPKRS2JYPRDVXJBM55PJNM/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":"2026-05-31T11:43:44Z","links":{"resolver":"https://pith.science/pith/WTBFOPKRS2JYPRDVXJBM55PJNM","bundle":"https://pith.science/pith/WTBFOPKRS2JYPRDVXJBM55PJNM/bundle.json","state":"https://pith.science/pith/WTBFOPKRS2JYPRDVXJBM55PJNM/state.json","well_known_bundle":"https://pith.science/.well-known/pith/WTBFOPKRS2JYPRDVXJBM55PJNM/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:WTBFOPKRS2JYPRDVXJBM55PJNM","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":"3de852675b230e25b72b0f6a6901461dda6f11723db87488068703ce16754dfe","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.plasm-ph","submitted_at":"2018-05-06T14:30:14Z","title_canon_sha256":"0f4f47fbf61e1e44810e7efe4583e500d83f00759c750fd7817630a2930b1f4f"},"schema_version":"1.0","source":{"id":"1805.02221","kind":"arxiv","version":3}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1805.02221","created_at":"2026-05-18T00:03:16Z"},{"alias_kind":"arxiv_version","alias_value":"1805.02221v3","created_at":"2026-05-18T00:03:16Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1805.02221","created_at":"2026-05-18T00:03:16Z"},{"alias_kind":"pith_short_12","alias_value":"WTBFOPKRS2JY","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_16","alias_value":"WTBFOPKRS2JYPRDV","created_at":"2026-05-18T12:33:01Z"},{"alias_kind":"pith_short_8","alias_value":"WTBFOPKR","created_at":"2026-05-18T12:33:01Z"}],"graph_snapshots":[{"event_id":"sha256:dc90236d818f177ee0708f0c98b6ea21da3bc37c848f2a2578b56147745c69c6","target":"graph","created_at":"2026-05-18T00:03:16Z","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":"The problem of finding an optimal curve for the target magnetic axis of a stellarator is addressed. Euler-Lagrange equations are derived for finite length three-dimensional curves that extremise their bending energy while yielding fixed integrated torsion. The obvious translational and rotational symmetry is exploited to express solutions in a preferred cylindrical coordinate system in terms of elliptic Jacobi functions. These solution curves, which, up to similarity transformations, depend on three dimensionless parameters, do not necessarily close. Two closure conditions are obtained for the","authors_text":"David Pfefferl\\'e, Lee Gunderson, Lyle Noakes, Stuart R. Hudson","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.plasm-ph","submitted_at":"2018-05-06T14:30:14Z","title":"Non-planar elasticae as optimal curves for the magnetic axis of stellarators"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1805.02221","kind":"arxiv","version":3},"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:ef3336a109695a679049c6ad5919952b407af0e7eb7dd1c6f589dde87b97549d","target":"record","created_at":"2026-05-18T00:03:16Z","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":"3de852675b230e25b72b0f6a6901461dda6f11723db87488068703ce16754dfe","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.plasm-ph","submitted_at":"2018-05-06T14:30:14Z","title_canon_sha256":"0f4f47fbf61e1e44810e7efe4583e500d83f00759c750fd7817630a2930b1f4f"},"schema_version":"1.0","source":{"id":"1805.02221","kind":"arxiv","version":3}},"canonical_sha256":"b4c2573d51969387c475ba42cef5e96b0b0489dc25d47aa4c26a4a6f5114f2ab","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"b4c2573d51969387c475ba42cef5e96b0b0489dc25d47aa4c26a4a6f5114f2ab","first_computed_at":"2026-05-18T00:03:16.662876Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:03:16.662876Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"49OpoToRcLkMJjIWm6H0roqKhlG3rlQW3S64ooVmMCcH83yyCV43VGWr2lfXegnhCJMbLoDi3gqj2jeGLkAuBA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:03:16.663386Z","signed_message":"canonical_sha256_bytes"},"source_id":"1805.02221","source_kind":"arxiv","source_version":3}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:ef3336a109695a679049c6ad5919952b407af0e7eb7dd1c6f589dde87b97549d","sha256:dc90236d818f177ee0708f0c98b6ea21da3bc37c848f2a2578b56147745c69c6"],"state_sha256":"645c06339ef73349aaa83213a1f830797da074b34224e569bf79150c69f02e88"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"IMleu8pVxjQpEehjYc3kjKteBqCdF69O6dmCqzjZd4euF1HEqKUPyrAFA65xnPC8JSwgnWjmUCq2QJLUzv2mDA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-31T11:43:44.812440Z","bundle_sha256":"4cb85646861bfc9d4dd3ba88ddbcbdbf0512d3ec878b48caab009038b4494aa8"}}