{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2021:KR4FKXV3JCYDZQJMORNT6NVKHA","short_pith_number":"pith:KR4FKXV3","canonical_record":{"source":{"id":"2110.14930","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2021-10-28T07:40:26Z","cross_cats_sorted":[],"title_canon_sha256":"5711c6f416ba804a5e2ba0ff1eaa2a500c8c373670544aa7b6c1b683412cd33c","abstract_canon_sha256":"8bbb9d798b85a52f94053d09390b2086d1a62ed7813e78aa82cd5b5d497f0f4f"},"schema_version":"1.0"},"canonical_sha256":"5478555ebb48b03cc12c745b3f36aa380e3eb8a75f7d0ff94bc3ba381bca0285","source":{"kind":"arxiv","id":"2110.14930","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2110.14930","created_at":"2026-07-05T03:40:50Z"},{"alias_kind":"arxiv_version","alias_value":"2110.14930v1","created_at":"2026-07-05T03:40:50Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2110.14930","created_at":"2026-07-05T03:40:50Z"},{"alias_kind":"pith_short_12","alias_value":"KR4FKXV3JCYD","created_at":"2026-07-05T03:40:50Z"},{"alias_kind":"pith_short_16","alias_value":"KR4FKXV3JCYDZQJM","created_at":"2026-07-05T03:40:50Z"},{"alias_kind":"pith_short_8","alias_value":"KR4FKXV3","created_at":"2026-07-05T03:40:50Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2021:KR4FKXV3JCYDZQJMORNT6NVKHA","target":"record","payload":{"canonical_record":{"source":{"id":"2110.14930","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2021-10-28T07:40:26Z","cross_cats_sorted":[],"title_canon_sha256":"5711c6f416ba804a5e2ba0ff1eaa2a500c8c373670544aa7b6c1b683412cd33c","abstract_canon_sha256":"8bbb9d798b85a52f94053d09390b2086d1a62ed7813e78aa82cd5b5d497f0f4f"},"schema_version":"1.0"},"canonical_sha256":"5478555ebb48b03cc12c745b3f36aa380e3eb8a75f7d0ff94bc3ba381bca0285","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T03:40:50.838504Z","signature_b64":"fugukuE1OEXZIhRPLomK4NA1UxO+LfRFTcsZ/myi7GxNR2hQgnuSNl3CXhu6+I98hKGs722r3qyf1KEBhZCYBQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"5478555ebb48b03cc12c745b3f36aa380e3eb8a75f7d0ff94bc3ba381bca0285","last_reissued_at":"2026-07-05T03:40:50.838110Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T03:40:50.838110Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2110.14930","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":"2026-07-05T03:40:50Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"LSqDibGSFTDCNjBQeJ6gWspEeiuuhejOsxI7chgviKVO/C0rDaeXuM2IactP3Kh+Y0JOybZmmEO/Hq5ZdsbLDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-04T12:59:50.967235Z"},"content_sha256":"c473795c5b6cf464d883947cf51b4a3aea390ec92fef203f7e34c0c1ffbdf97a","schema_version":"1.0","event_id":"sha256:c473795c5b6cf464d883947cf51b4a3aea390ec92fef203f7e34c0c1ffbdf97a"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2021:KR4FKXV3JCYDZQJMORNT6NVKHA","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"NICER study of pulsed thermal X-rays from Calvera: a neutron star born in the Galactic halo?","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.HE","authors_text":"L. Baldeschi, M. Rigoselli, R. Taverna, R. Turolla, S. Crestan, S. Mereghetti, S. Zane","submitted_at":"2021-10-28T07:40:26Z","abstract_excerpt":"Calvera (1RXS J141256.0+792204) is an isolated neutron star detected only through its thermal X-ray emission. Its location at high Galactic latitude ($b=+37^\\circ$) is unusual if Calvera is a relatively young pulsar, as suggested by its spin period (59 ms) and period derivative ($3.2 \\times 10^{-15}$ Hz s$^{-1}$). Using the Neutron Star Interior Composition Explorer (NICER), we obtained a phase-connected timing solution spanning four years which allowed us to measure the second derivative of the frequency $\\ddot\\nu = -2.5 \\times 10^{-23}$ Hz s$^{-2}$ and to reveal timing noise consistent with "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2110.14930","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2110.14930/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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":"2026-07-05T03:40:50Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"WCLl6Tzz34W+2Y16ePVMcoA2VVBU0Eh6QZAZOyCuwYB7W2jkkbrUeDFu5TgMvlBf4Kgw+o+6UEPhwD+tWLVADA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-04T12:59:50.968250Z"},"content_sha256":"4f8e0be648357f8c2cea0c13842897506009d220a1bbff151cc7248ddf44f0cd","schema_version":"1.0","event_id":"sha256:4f8e0be648357f8c2cea0c13842897506009d220a1bbff151cc7248ddf44f0cd"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/KR4FKXV3JCYDZQJMORNT6NVKHA/bundle.json","state_url":"https://pith.science/pith/KR4FKXV3JCYDZQJMORNT6NVKHA/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/KR4FKXV3JCYDZQJMORNT6NVKHA/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":"2026-08-04T12:59:50Z","links":{"resolver":"https://pith.science/pith/KR4FKXV3JCYDZQJMORNT6NVKHA","bundle":"https://pith.science/pith/KR4FKXV3JCYDZQJMORNT6NVKHA/bundle.json","state":"https://pith.science/pith/KR4FKXV3JCYDZQJMORNT6NVKHA/state.json","well_known_bundle":"https://pith.science/.well-known/pith/KR4FKXV3JCYDZQJMORNT6NVKHA/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2021:KR4FKXV3JCYDZQJMORNT6NVKHA","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":"8bbb9d798b85a52f94053d09390b2086d1a62ed7813e78aa82cd5b5d497f0f4f","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2021-10-28T07:40:26Z","title_canon_sha256":"5711c6f416ba804a5e2ba0ff1eaa2a500c8c373670544aa7b6c1b683412cd33c"},"schema_version":"1.0","source":{"id":"2110.14930","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2110.14930","created_at":"2026-07-05T03:40:50Z"},{"alias_kind":"arxiv_version","alias_value":"2110.14930v1","created_at":"2026-07-05T03:40:50Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2110.14930","created_at":"2026-07-05T03:40:50Z"},{"alias_kind":"pith_short_12","alias_value":"KR4FKXV3JCYD","created_at":"2026-07-05T03:40:50Z"},{"alias_kind":"pith_short_16","alias_value":"KR4FKXV3JCYDZQJM","created_at":"2026-07-05T03:40:50Z"},{"alias_kind":"pith_short_8","alias_value":"KR4FKXV3","created_at":"2026-07-05T03:40:50Z"}],"graph_snapshots":[{"event_id":"sha256:4f8e0be648357f8c2cea0c13842897506009d220a1bbff151cc7248ddf44f0cd","target":"graph","created_at":"2026-07-05T03:40:50Z","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"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2110.14930/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Calvera (1RXS J141256.0+792204) is an isolated neutron star detected only through its thermal X-ray emission. Its location at high Galactic latitude ($b=+37^\\circ$) is unusual if Calvera is a relatively young pulsar, as suggested by its spin period (59 ms) and period derivative ($3.2 \\times 10^{-15}$ Hz s$^{-1}$). Using the Neutron Star Interior Composition Explorer (NICER), we obtained a phase-connected timing solution spanning four years which allowed us to measure the second derivative of the frequency $\\ddot\\nu = -2.5 \\times 10^{-23}$ Hz s$^{-2}$ and to reveal timing noise consistent with ","authors_text":"L. Baldeschi, M. Rigoselli, R. Taverna, R. Turolla, S. Crestan, S. Mereghetti, S. Zane","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2021-10-28T07:40:26Z","title":"NICER study of pulsed thermal X-rays from Calvera: a neutron star born in the Galactic halo?"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2110.14930","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:c473795c5b6cf464d883947cf51b4a3aea390ec92fef203f7e34c0c1ffbdf97a","target":"record","created_at":"2026-07-05T03:40:50Z","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":"8bbb9d798b85a52f94053d09390b2086d1a62ed7813e78aa82cd5b5d497f0f4f","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.HE","submitted_at":"2021-10-28T07:40:26Z","title_canon_sha256":"5711c6f416ba804a5e2ba0ff1eaa2a500c8c373670544aa7b6c1b683412cd33c"},"schema_version":"1.0","source":{"id":"2110.14930","kind":"arxiv","version":1}},"canonical_sha256":"5478555ebb48b03cc12c745b3f36aa380e3eb8a75f7d0ff94bc3ba381bca0285","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"5478555ebb48b03cc12c745b3f36aa380e3eb8a75f7d0ff94bc3ba381bca0285","first_computed_at":"2026-07-05T03:40:50.838110Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T03:40:50.838110Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"fugukuE1OEXZIhRPLomK4NA1UxO+LfRFTcsZ/myi7GxNR2hQgnuSNl3CXhu6+I98hKGs722r3qyf1KEBhZCYBQ==","signature_status":"signed_v1","signed_at":"2026-07-05T03:40:50.838504Z","signed_message":"canonical_sha256_bytes"},"source_id":"2110.14930","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:c473795c5b6cf464d883947cf51b4a3aea390ec92fef203f7e34c0c1ffbdf97a","sha256:4f8e0be648357f8c2cea0c13842897506009d220a1bbff151cc7248ddf44f0cd"],"state_sha256":"588110495db70b8bb9507add8d88ee9dadfdb316706ccd8d9a0b802aee2279fb"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"hJEUfuBYbCXjql7OQYS6TdmEN9KQX501JNsX/hQJuQ5omIIRDPgsswq2OpqFJctnzp5fZ6FoR9xRkDlWICBeCg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-04T12:59:50.974246Z","bundle_sha256":"83c05b096e5bfbf759ecc2e44be378bdc1b5b22d7e78778746f3981dff228da6"}}