{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2013:ZBRFEB3UBA6ZEUJRL7FN6XKWG5","short_pith_number":"pith:ZBRFEB3U","canonical_record":{"source":{"id":"1301.6642","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2013-01-28T18:49:16Z","cross_cats_sorted":[],"title_canon_sha256":"db86e3c6f918e4ec0e765a58cfdf8c5bb2707adf96bafb19b22e7f59d0e87d07","abstract_canon_sha256":"c8c25fd1db42b36e07393fbee7ef2a42cdd7074386069c545e7de6ce9b005091"},"schema_version":"1.0"},"canonical_sha256":"c862520774083d9251315fcadf5d5637446ed6b48bd8e639291bb39fc9d3ef5e","source":{"kind":"arxiv","id":"1301.6642","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1301.6642","created_at":"2026-05-18T01:00:20Z"},{"alias_kind":"arxiv_version","alias_value":"1301.6642v1","created_at":"2026-05-18T01:00:20Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1301.6642","created_at":"2026-05-18T01:00:20Z"},{"alias_kind":"pith_short_12","alias_value":"ZBRFEB3UBA6Z","created_at":"2026-05-18T12:28:09Z"},{"alias_kind":"pith_short_16","alias_value":"ZBRFEB3UBA6ZEUJR","created_at":"2026-05-18T12:28:09Z"},{"alias_kind":"pith_short_8","alias_value":"ZBRFEB3U","created_at":"2026-05-18T12:28:09Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2013:ZBRFEB3UBA6ZEUJRL7FN6XKWG5","target":"record","payload":{"canonical_record":{"source":{"id":"1301.6642","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2013-01-28T18:49:16Z","cross_cats_sorted":[],"title_canon_sha256":"db86e3c6f918e4ec0e765a58cfdf8c5bb2707adf96bafb19b22e7f59d0e87d07","abstract_canon_sha256":"c8c25fd1db42b36e07393fbee7ef2a42cdd7074386069c545e7de6ce9b005091"},"schema_version":"1.0"},"canonical_sha256":"c862520774083d9251315fcadf5d5637446ed6b48bd8e639291bb39fc9d3ef5e","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:00:20.822191Z","signature_b64":"n+TF5jkPowzVup0aNtzAWn13IxwVd0geWOd4W/X+zlySNPsRBHBtgNLInbaGSNRM4EffLXVFTPcIfa5KmzN1Aw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"c862520774083d9251315fcadf5d5637446ed6b48bd8e639291bb39fc9d3ef5e","last_reissued_at":"2026-05-18T01:00:20.821627Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:00:20.821627Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1301.6642","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":"2026-05-18T01:00:20Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"csU/mHKTqQKWGyRw2Mf/svWWNAxgys3kVtiWReDNQoWa3hap3wz8ZZLNPsE3LcEJPLzDmootKDLnt55ITU2dDA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-20T00:08:23.892728Z"},"content_sha256":"1a0502134cba15e46197352877ad57abab531c349413e1ec35dffb140986ad16","schema_version":"1.0","event_id":"sha256:1a0502134cba15e46197352877ad57abab531c349413e1ec35dffb140986ad16"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2013:ZBRFEB3UBA6ZEUJRL7FN6XKWG5","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Studies of NGC 6720 with Calibrated HST WFC3 Emission-Line Filter Images--II:Physical Conditions","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"C. R. O'Dell, G. J. Ferland, Manuel Peimbert, W. J. Henney","submitted_at":"2013-01-28T18:49:16Z","abstract_excerpt":"We have performed a detailed analysis of the electron temperature and density in the the Ring Nebula using the calibrated HST WFC3 images described in the preceding paper. The electron temperature (Te) determined from [N II] and [O III] rises slightly and monotonically towards the central star. The observed equivalent width (EW) in the central region indicates that Te rises as high as 13000 K. In contrast, the low EW's in the outer regions are largely due to scattered diffuse Galactic radiation by dust. The images allowed determination of unprecedented small scale variations in Te. These varia"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1301.6642","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":"2026-05-18T01:00:20Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"tKfQUzms32dfKsDoDq+f395fxD41954WQ99DdonUjS4H2wWgFgVNidz6y8hJyJDdjgECPUYqpF47ngzuTLbJDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-20T00:08:23.893418Z"},"content_sha256":"6b56f6d1e1e8d7cf0e852bfed4cd1e105e974b416d22ae274ca8cef40f73300b","schema_version":"1.0","event_id":"sha256:6b56f6d1e1e8d7cf0e852bfed4cd1e105e974b416d22ae274ca8cef40f73300b"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/ZBRFEB3UBA6ZEUJRL7FN6XKWG5/bundle.json","state_url":"https://pith.science/pith/ZBRFEB3UBA6ZEUJRL7FN6XKWG5/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/ZBRFEB3UBA6ZEUJRL7FN6XKWG5/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":"2026-05-20T00:08:23Z","links":{"resolver":"https://pith.science/pith/ZBRFEB3UBA6ZEUJRL7FN6XKWG5","bundle":"https://pith.science/pith/ZBRFEB3UBA6ZEUJRL7FN6XKWG5/bundle.json","state":"https://pith.science/pith/ZBRFEB3UBA6ZEUJRL7FN6XKWG5/state.json","well_known_bundle":"https://pith.science/.well-known/pith/ZBRFEB3UBA6ZEUJRL7FN6XKWG5/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2013:ZBRFEB3UBA6ZEUJRL7FN6XKWG5","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":"c8c25fd1db42b36e07393fbee7ef2a42cdd7074386069c545e7de6ce9b005091","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2013-01-28T18:49:16Z","title_canon_sha256":"db86e3c6f918e4ec0e765a58cfdf8c5bb2707adf96bafb19b22e7f59d0e87d07"},"schema_version":"1.0","source":{"id":"1301.6642","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1301.6642","created_at":"2026-05-18T01:00:20Z"},{"alias_kind":"arxiv_version","alias_value":"1301.6642v1","created_at":"2026-05-18T01:00:20Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1301.6642","created_at":"2026-05-18T01:00:20Z"},{"alias_kind":"pith_short_12","alias_value":"ZBRFEB3UBA6Z","created_at":"2026-05-18T12:28:09Z"},{"alias_kind":"pith_short_16","alias_value":"ZBRFEB3UBA6ZEUJR","created_at":"2026-05-18T12:28:09Z"},{"alias_kind":"pith_short_8","alias_value":"ZBRFEB3U","created_at":"2026-05-18T12:28:09Z"}],"graph_snapshots":[{"event_id":"sha256:6b56f6d1e1e8d7cf0e852bfed4cd1e105e974b416d22ae274ca8cef40f73300b","target":"graph","created_at":"2026-05-18T01:00:20Z","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":"We have performed a detailed analysis of the electron temperature and density in the the Ring Nebula using the calibrated HST WFC3 images described in the preceding paper. The electron temperature (Te) determined from [N II] and [O III] rises slightly and monotonically towards the central star. The observed equivalent width (EW) in the central region indicates that Te rises as high as 13000 K. In contrast, the low EW's in the outer regions are largely due to scattered diffuse Galactic radiation by dust. The images allowed determination of unprecedented small scale variations in Te. These varia","authors_text":"C. R. O'Dell, G. J. Ferland, Manuel Peimbert, W. J. Henney","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2013-01-28T18:49:16Z","title":"Studies of NGC 6720 with Calibrated HST WFC3 Emission-Line Filter Images--II:Physical Conditions"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1301.6642","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":"sha256:1a0502134cba15e46197352877ad57abab531c349413e1ec35dffb140986ad16","target":"record","created_at":"2026-05-18T01:00:20Z","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":"c8c25fd1db42b36e07393fbee7ef2a42cdd7074386069c545e7de6ce9b005091","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2013-01-28T18:49:16Z","title_canon_sha256":"db86e3c6f918e4ec0e765a58cfdf8c5bb2707adf96bafb19b22e7f59d0e87d07"},"schema_version":"1.0","source":{"id":"1301.6642","kind":"arxiv","version":1}},"canonical_sha256":"c862520774083d9251315fcadf5d5637446ed6b48bd8e639291bb39fc9d3ef5e","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"c862520774083d9251315fcadf5d5637446ed6b48bd8e639291bb39fc9d3ef5e","first_computed_at":"2026-05-18T01:00:20.821627Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:00:20.821627Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"n+TF5jkPowzVup0aNtzAWn13IxwVd0geWOd4W/X+zlySNPsRBHBtgNLInbaGSNRM4EffLXVFTPcIfa5KmzN1Aw==","signature_status":"signed_v1","signed_at":"2026-05-18T01:00:20.822191Z","signed_message":"canonical_sha256_bytes"},"source_id":"1301.6642","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:1a0502134cba15e46197352877ad57abab531c349413e1ec35dffb140986ad16","sha256:6b56f6d1e1e8d7cf0e852bfed4cd1e105e974b416d22ae274ca8cef40f73300b"],"state_sha256":"c92709632fe77668422f05916f08ac01783322d211060cdde37f8c99b21ed7bb"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"zUBBru20U1F+ZulUupVYJ/OpAm3ftQXpiWSyXL4HcDvWoz8Zlw/8P836b38qgC3+suKM4XssmoCc2LEZiPQiCQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-20T00:08:23.897417Z","bundle_sha256":"15875c5c3d0c66d5289f2a999247f50a0ad973b747aaae25846fd3f2d8520b06"}}