{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2013:ONCRJ2BNBV5VA7RVZDCSJMDOBA","short_pith_number":"pith:ONCRJ2BN","canonical_record":{"source":{"id":"1312.6148","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2013-12-20T21:31:09Z","cross_cats_sorted":[],"title_canon_sha256":"a2bead1203772f473728210ddd2a839018a59617f32482d4ee2528053ea9c234","abstract_canon_sha256":"ab222daeddee8070ac0e94f20bd9a63a0d5af19957a0d80a98f40830481bb480"},"schema_version":"1.0"},"canonical_sha256":"734514e82d0d7b507e35c8c524b06e0809412d8f97cdcd0584fe615a31a336b9","source":{"kind":"arxiv","id":"1312.6148","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1312.6148","created_at":"2026-05-18T01:45:43Z"},{"alias_kind":"arxiv_version","alias_value":"1312.6148v1","created_at":"2026-05-18T01:45:43Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1312.6148","created_at":"2026-05-18T01:45:43Z"},{"alias_kind":"pith_short_12","alias_value":"ONCRJ2BNBV5V","created_at":"2026-05-18T12:27:54Z"},{"alias_kind":"pith_short_16","alias_value":"ONCRJ2BNBV5VA7RV","created_at":"2026-05-18T12:27:54Z"},{"alias_kind":"pith_short_8","alias_value":"ONCRJ2BN","created_at":"2026-05-18T12:27:54Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2013:ONCRJ2BNBV5VA7RVZDCSJMDOBA","target":"record","payload":{"canonical_record":{"source":{"id":"1312.6148","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2013-12-20T21:31:09Z","cross_cats_sorted":[],"title_canon_sha256":"a2bead1203772f473728210ddd2a839018a59617f32482d4ee2528053ea9c234","abstract_canon_sha256":"ab222daeddee8070ac0e94f20bd9a63a0d5af19957a0d80a98f40830481bb480"},"schema_version":"1.0"},"canonical_sha256":"734514e82d0d7b507e35c8c524b06e0809412d8f97cdcd0584fe615a31a336b9","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:45:43.024820Z","signature_b64":"4azHYv+nhNaMUx6Z2/ohpy8akXmRWu1tXqsk/qszbmk1fIOwP8sO9XoPw62YtORASWkpdnikRQafvgKfqjcnAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"734514e82d0d7b507e35c8c524b06e0809412d8f97cdcd0584fe615a31a336b9","last_reissued_at":"2026-05-18T01:45:43.024246Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:45:43.024246Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1312.6148","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":"2026-05-18T01:45:43Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"fqUbEqaj0B7IP1sG8MY/7HI3yLq6hs5X6FDeNC4U6ykjRItT0VanmxRLEhCr3opUiK/Y/rGwTWFAdNT3GIZZCQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-28T14:39:53.864156Z"},"content_sha256":"2ce2a83a093c6cb076585c564ebca70dca8afb8f852653bb6aed7bb260052a3f","schema_version":"1.0","event_id":"sha256:2ce2a83a093c6cb076585c564ebca70dca8afb8f852653bb6aed7bb260052a3f"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2013:ONCRJ2BNBV5VA7RVZDCSJMDOBA","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Instrumental polarisation at the Nasmyth focus of the E-ELT","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.IM","authors_text":"C. U. Keller, F. Snik, L. Venema, M. de Juan Ovelar","submitted_at":"2013-12-20T21:31:09Z","abstract_excerpt":"The ~39-m European Extremely Large Telescope (E-ELT) will be the largest telescope ever built. This makes it particularly suitable for sensitive polarimetric observations, as polarimetry is a photon-starved technique. However, the telescope mirrors may severely limit the polarimetric accuracy of instruments on the Nasmyth platforms by creating instrumental polarisation and/or modifying the polarisation signal of the object. In this paper we characterise the polarisation effects of the two currently considered designs for the E-ELT Nasmyth ports as well as the effect of ageing of the mirrors. B"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1312.6148","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":"2026-05-18T01:45:43Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"pjdC+G1KyCCdXv88rC5Z+DdAQSQsz/a8Osj6UIY7zQsMT6N3+MAJhxGwQiKmxK3Nr28ujZncVk59WKy2O8nDDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-28T14:39:53.864494Z"},"content_sha256":"013abfa2fc3c3a9cea1c6aacc315e95277047a80865e99c11dc2f49e68a774fc","schema_version":"1.0","event_id":"sha256:013abfa2fc3c3a9cea1c6aacc315e95277047a80865e99c11dc2f49e68a774fc"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/ONCRJ2BNBV5VA7RVZDCSJMDOBA/bundle.json","state_url":"https://pith.science/pith/ONCRJ2BNBV5VA7RVZDCSJMDOBA/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/ONCRJ2BNBV5VA7RVZDCSJMDOBA/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":"2026-06-28T14:39:53Z","links":{"resolver":"https://pith.science/pith/ONCRJ2BNBV5VA7RVZDCSJMDOBA","bundle":"https://pith.science/pith/ONCRJ2BNBV5VA7RVZDCSJMDOBA/bundle.json","state":"https://pith.science/pith/ONCRJ2BNBV5VA7RVZDCSJMDOBA/state.json","well_known_bundle":"https://pith.science/.well-known/pith/ONCRJ2BNBV5VA7RVZDCSJMDOBA/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2013:ONCRJ2BNBV5VA7RVZDCSJMDOBA","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":"ab222daeddee8070ac0e94f20bd9a63a0d5af19957a0d80a98f40830481bb480","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2013-12-20T21:31:09Z","title_canon_sha256":"a2bead1203772f473728210ddd2a839018a59617f32482d4ee2528053ea9c234"},"schema_version":"1.0","source":{"id":"1312.6148","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1312.6148","created_at":"2026-05-18T01:45:43Z"},{"alias_kind":"arxiv_version","alias_value":"1312.6148v1","created_at":"2026-05-18T01:45:43Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1312.6148","created_at":"2026-05-18T01:45:43Z"},{"alias_kind":"pith_short_12","alias_value":"ONCRJ2BNBV5V","created_at":"2026-05-18T12:27:54Z"},{"alias_kind":"pith_short_16","alias_value":"ONCRJ2BNBV5VA7RV","created_at":"2026-05-18T12:27:54Z"},{"alias_kind":"pith_short_8","alias_value":"ONCRJ2BN","created_at":"2026-05-18T12:27:54Z"}],"graph_snapshots":[{"event_id":"sha256:013abfa2fc3c3a9cea1c6aacc315e95277047a80865e99c11dc2f49e68a774fc","target":"graph","created_at":"2026-05-18T01:45:43Z","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 ~39-m European Extremely Large Telescope (E-ELT) will be the largest telescope ever built. This makes it particularly suitable for sensitive polarimetric observations, as polarimetry is a photon-starved technique. However, the telescope mirrors may severely limit the polarimetric accuracy of instruments on the Nasmyth platforms by creating instrumental polarisation and/or modifying the polarisation signal of the object. In this paper we characterise the polarisation effects of the two currently considered designs for the E-ELT Nasmyth ports as well as the effect of ageing of the mirrors. B","authors_text":"C. U. Keller, F. Snik, L. Venema, M. de Juan Ovelar","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2013-12-20T21:31:09Z","title":"Instrumental polarisation at the Nasmyth focus of the E-ELT"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1312.6148","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":"sha256:2ce2a83a093c6cb076585c564ebca70dca8afb8f852653bb6aed7bb260052a3f","target":"record","created_at":"2026-05-18T01:45:43Z","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":"ab222daeddee8070ac0e94f20bd9a63a0d5af19957a0d80a98f40830481bb480","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.IM","submitted_at":"2013-12-20T21:31:09Z","title_canon_sha256":"a2bead1203772f473728210ddd2a839018a59617f32482d4ee2528053ea9c234"},"schema_version":"1.0","source":{"id":"1312.6148","kind":"arxiv","version":1}},"canonical_sha256":"734514e82d0d7b507e35c8c524b06e0809412d8f97cdcd0584fe615a31a336b9","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"734514e82d0d7b507e35c8c524b06e0809412d8f97cdcd0584fe615a31a336b9","first_computed_at":"2026-05-18T01:45:43.024246Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:45:43.024246Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"4azHYv+nhNaMUx6Z2/ohpy8akXmRWu1tXqsk/qszbmk1fIOwP8sO9XoPw62YtORASWkpdnikRQafvgKfqjcnAA==","signature_status":"signed_v1","signed_at":"2026-05-18T01:45:43.024820Z","signed_message":"canonical_sha256_bytes"},"source_id":"1312.6148","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:2ce2a83a093c6cb076585c564ebca70dca8afb8f852653bb6aed7bb260052a3f","sha256:013abfa2fc3c3a9cea1c6aacc315e95277047a80865e99c11dc2f49e68a774fc"],"state_sha256":"33b2d0bc7d5b895fa0647171a5dc703c5f8e205e3069d7e5155c2519381280f4"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"AWyPS2RJY9ka5nn+TYEVNbpMHJdp5CU77Sr2a1I814NAGOW3Sjxk5wdF9Q9zjOwRUi3dWuF08mBx3sNu4PcbCQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-28T14:39:53.866265Z","bundle_sha256":"1cf172f58fc623552bf4e732a0fd25e916f888a4b8eac12c8c4b4bb3804855f1"}}