{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:2V7RYVWTLLWCXPIKBJZGZBUVBN","short_pith_number":"pith:2V7RYVWT","canonical_record":{"source":{"id":"1901.04548","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ins-det","submitted_at":"2019-01-14T20:21:15Z","cross_cats_sorted":["nucl-ex"],"title_canon_sha256":"d797cb44df03b847ae3f5bce93a851ba5d54cf88ba36286ca5b24b06026c9d16","abstract_canon_sha256":"4965d53e72e7115e0028894623606013b1785121671993323c5a92087bb104b0"},"schema_version":"1.0"},"canonical_sha256":"d57f1c56d35aec2bbd0a0a726c86950b67e6a83292ab1b6740fa6b9ec0a4e51b","source":{"kind":"arxiv","id":"1901.04548","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1901.04548","created_at":"2026-05-17T23:56:22Z"},{"alias_kind":"arxiv_version","alias_value":"1901.04548v1","created_at":"2026-05-17T23:56:22Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1901.04548","created_at":"2026-05-17T23:56:22Z"},{"alias_kind":"pith_short_12","alias_value":"2V7RYVWTLLWC","created_at":"2026-05-18T12:33:07Z"},{"alias_kind":"pith_short_16","alias_value":"2V7RYVWTLLWCXPIK","created_at":"2026-05-18T12:33:07Z"},{"alias_kind":"pith_short_8","alias_value":"2V7RYVWT","created_at":"2026-05-18T12:33:07Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:2V7RYVWTLLWCXPIKBJZGZBUVBN","target":"record","payload":{"canonical_record":{"source":{"id":"1901.04548","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ins-det","submitted_at":"2019-01-14T20:21:15Z","cross_cats_sorted":["nucl-ex"],"title_canon_sha256":"d797cb44df03b847ae3f5bce93a851ba5d54cf88ba36286ca5b24b06026c9d16","abstract_canon_sha256":"4965d53e72e7115e0028894623606013b1785121671993323c5a92087bb104b0"},"schema_version":"1.0"},"canonical_sha256":"d57f1c56d35aec2bbd0a0a726c86950b67e6a83292ab1b6740fa6b9ec0a4e51b","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:56:22.432718Z","signature_b64":"HzJIqGmtXYJ3XJa4v4DvKpJuzFCPtFIi7KMcgDnhABvp1rUIukdwrOTA9jOunGCkMgQB45biRf27aYNayT8tCQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"d57f1c56d35aec2bbd0a0a726c86950b67e6a83292ab1b6740fa6b9ec0a4e51b","last_reissued_at":"2026-05-17T23:56:22.432178Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:56:22.432178Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1901.04548","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":"2026-05-17T23:56:22Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"0nmsoM/Nba3sJLhYE5MDlj1SUsjBwAA4rIcrhvpsnjPqkTmAOOMP8I6aikMX+92E+kQZEFYP8v5yfuFdXzA9Dg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-19T18:22:57.320042Z"},"content_sha256":"adb8d5918d5c702a48e408dadb1e84a16a44a4eb172a437e99fbfe4d962640e4","schema_version":"1.0","event_id":"sha256:adb8d5918d5c702a48e408dadb1e84a16a44a4eb172a437e99fbfe4d962640e4"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:2V7RYVWTLLWCXPIKBJZGZBUVBN","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"A cryostat to hold frozen-spin polarized HD targets in CLAS: HDice-II","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["nucl-ex"],"primary_cat":"physics.ins-det","authors_text":"A. D'Angelo, A. Deur, A. M. Sandorfi, C. D. Bass, C. Hanretty, D. Ho, D. Kashy, D. Sokhan, G. Dezern, M. Khandaker, M. M. Lowry, M. Zarecky, O. Pastor, P. Peng, T. Kageya, T. O'Connell, V. Laine, X. Wei","submitted_at":"2019-01-14T20:21:15Z","abstract_excerpt":"The design, fabrication, operation, and performance of a helium-3/4 dilution refrigerator and superconducting magnet system for holding a frozen-spin polarized hydrogen deuteride target in the Jefferson Laboratory CLAS detector during photon beam running is reported. The device operates both vertically (for target loading) and horizontally (for target bombardment). The device proves capable of maintaining a base temperature of 50 mK and a holding field of 1 Tesla for extended periods. These characteristics enabled multi-month polarization lifetimes for frozen spin HD targets having proton pola"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1901.04548","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":"2026-05-17T23:56:22Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"d1TRvek4t+ILmxEm99GZyDnewc0wZX4cMzczNw/e7HiUEk7vYfQfE1x2pD6MC5rWzUUAO//gN9unLuuc8UXKAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-19T18:22:57.320410Z"},"content_sha256":"4103c94ee929816cf3e43827185dc5ba4a347cf22773c6f1f9bb5b605ab8aa37","schema_version":"1.0","event_id":"sha256:4103c94ee929816cf3e43827185dc5ba4a347cf22773c6f1f9bb5b605ab8aa37"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/2V7RYVWTLLWCXPIKBJZGZBUVBN/bundle.json","state_url":"https://pith.science/pith/2V7RYVWTLLWCXPIKBJZGZBUVBN/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/2V7RYVWTLLWCXPIKBJZGZBUVBN/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":"2026-05-19T18:22:57Z","links":{"resolver":"https://pith.science/pith/2V7RYVWTLLWCXPIKBJZGZBUVBN","bundle":"https://pith.science/pith/2V7RYVWTLLWCXPIKBJZGZBUVBN/bundle.json","state":"https://pith.science/pith/2V7RYVWTLLWCXPIKBJZGZBUVBN/state.json","well_known_bundle":"https://pith.science/.well-known/pith/2V7RYVWTLLWCXPIKBJZGZBUVBN/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:2V7RYVWTLLWCXPIKBJZGZBUVBN","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":"4965d53e72e7115e0028894623606013b1785121671993323c5a92087bb104b0","cross_cats_sorted":["nucl-ex"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ins-det","submitted_at":"2019-01-14T20:21:15Z","title_canon_sha256":"d797cb44df03b847ae3f5bce93a851ba5d54cf88ba36286ca5b24b06026c9d16"},"schema_version":"1.0","source":{"id":"1901.04548","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1901.04548","created_at":"2026-05-17T23:56:22Z"},{"alias_kind":"arxiv_version","alias_value":"1901.04548v1","created_at":"2026-05-17T23:56:22Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1901.04548","created_at":"2026-05-17T23:56:22Z"},{"alias_kind":"pith_short_12","alias_value":"2V7RYVWTLLWC","created_at":"2026-05-18T12:33:07Z"},{"alias_kind":"pith_short_16","alias_value":"2V7RYVWTLLWCXPIK","created_at":"2026-05-18T12:33:07Z"},{"alias_kind":"pith_short_8","alias_value":"2V7RYVWT","created_at":"2026-05-18T12:33:07Z"}],"graph_snapshots":[{"event_id":"sha256:4103c94ee929816cf3e43827185dc5ba4a347cf22773c6f1f9bb5b605ab8aa37","target":"graph","created_at":"2026-05-17T23:56:22Z","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 design, fabrication, operation, and performance of a helium-3/4 dilution refrigerator and superconducting magnet system for holding a frozen-spin polarized hydrogen deuteride target in the Jefferson Laboratory CLAS detector during photon beam running is reported. The device operates both vertically (for target loading) and horizontally (for target bombardment). The device proves capable of maintaining a base temperature of 50 mK and a holding field of 1 Tesla for extended periods. These characteristics enabled multi-month polarization lifetimes for frozen spin HD targets having proton pola","authors_text":"A. D'Angelo, A. Deur, A. M. Sandorfi, C. D. Bass, C. Hanretty, D. Ho, D. Kashy, D. Sokhan, G. Dezern, M. Khandaker, M. M. Lowry, M. Zarecky, O. Pastor, P. Peng, T. Kageya, T. O'Connell, V. Laine, X. Wei","cross_cats":["nucl-ex"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ins-det","submitted_at":"2019-01-14T20:21:15Z","title":"A cryostat to hold frozen-spin polarized HD targets in CLAS: HDice-II"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1901.04548","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:adb8d5918d5c702a48e408dadb1e84a16a44a4eb172a437e99fbfe4d962640e4","target":"record","created_at":"2026-05-17T23:56:22Z","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":"4965d53e72e7115e0028894623606013b1785121671993323c5a92087bb104b0","cross_cats_sorted":["nucl-ex"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"physics.ins-det","submitted_at":"2019-01-14T20:21:15Z","title_canon_sha256":"d797cb44df03b847ae3f5bce93a851ba5d54cf88ba36286ca5b24b06026c9d16"},"schema_version":"1.0","source":{"id":"1901.04548","kind":"arxiv","version":1}},"canonical_sha256":"d57f1c56d35aec2bbd0a0a726c86950b67e6a83292ab1b6740fa6b9ec0a4e51b","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"d57f1c56d35aec2bbd0a0a726c86950b67e6a83292ab1b6740fa6b9ec0a4e51b","first_computed_at":"2026-05-17T23:56:22.432178Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:56:22.432178Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"HzJIqGmtXYJ3XJa4v4DvKpJuzFCPtFIi7KMcgDnhABvp1rUIukdwrOTA9jOunGCkMgQB45biRf27aYNayT8tCQ==","signature_status":"signed_v1","signed_at":"2026-05-17T23:56:22.432718Z","signed_message":"canonical_sha256_bytes"},"source_id":"1901.04548","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:adb8d5918d5c702a48e408dadb1e84a16a44a4eb172a437e99fbfe4d962640e4","sha256:4103c94ee929816cf3e43827185dc5ba4a347cf22773c6f1f9bb5b605ab8aa37"],"state_sha256":"d563c98288f6ceab946ec4fc0970a7ead7858d233fc2a6f8aa88f7a9eba9a2b0"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"sJV9HAYR7hADosWHpvA0NK7BxwL2c3YEpFpWpKr4ddmwkh7F4JnfoAygdjS6piQNA5ZXKc7W/BdL338ltYPHBw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-19T18:22:57.322548Z","bundle_sha256":"5250a0181d29f61ef6e0f312a8f4a1c01ed71284ac08e7a37f987a7f88238003"}}