{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2017:MBKW7J6ONST5IHSWDM67N4YKRX","short_pith_number":"pith:MBKW7J6O","canonical_record":{"source":{"id":"1710.05926","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-10-16T18:00:04Z","cross_cats_sorted":["astro-ph.SR"],"title_canon_sha256":"3185fbb19e54d4529418a8f0fbac89255ef446c5ee386af91eb9d42bd41f361a","abstract_canon_sha256":"412665ee984d9bb4e5ab7e82b48d1ae9dfd168856ad901f64e79ec99cf9331e2"},"schema_version":"1.0"},"canonical_sha256":"60556fa7ce6ca7d41e561b3df6f30a8de9422bffdb613505cb780630137a26fb","source":{"kind":"arxiv","id":"1710.05926","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1710.05926","created_at":"2026-05-18T00:23:32Z"},{"alias_kind":"arxiv_version","alias_value":"1710.05926v1","created_at":"2026-05-18T00:23:32Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1710.05926","created_at":"2026-05-18T00:23:32Z"},{"alias_kind":"pith_short_12","alias_value":"MBKW7J6ONST5","created_at":"2026-05-18T12:31:31Z"},{"alias_kind":"pith_short_16","alias_value":"MBKW7J6ONST5IHSW","created_at":"2026-05-18T12:31:31Z"},{"alias_kind":"pith_short_8","alias_value":"MBKW7J6O","created_at":"2026-05-18T12:31:31Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2017:MBKW7J6ONST5IHSWDM67N4YKRX","target":"record","payload":{"canonical_record":{"source":{"id":"1710.05926","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-10-16T18:00:04Z","cross_cats_sorted":["astro-ph.SR"],"title_canon_sha256":"3185fbb19e54d4529418a8f0fbac89255ef446c5ee386af91eb9d42bd41f361a","abstract_canon_sha256":"412665ee984d9bb4e5ab7e82b48d1ae9dfd168856ad901f64e79ec99cf9331e2"},"schema_version":"1.0"},"canonical_sha256":"60556fa7ce6ca7d41e561b3df6f30a8de9422bffdb613505cb780630137a26fb","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:23:32.427907Z","signature_b64":"xAeFNxunV7eWwM4T4Ufa7dgPWXUskH/USwYaaANXyknhNqZq6ITF57f8/HSO88QxXmoyLpEfbbiFNR+wpa8gAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"60556fa7ce6ca7d41e561b3df6f30a8de9422bffdb613505cb780630137a26fb","last_reissued_at":"2026-05-18T00:23:32.427387Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:23:32.427387Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1710.05926","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":"2026-05-18T00:23:32Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"X5WBTdYLQ4awb2IrTvCWKjtcAs4/EpqfC1bBEPpJ2bRFD59PrUbCi5k5PLfOYdSTiWtbupa6sAI/fnzxQ2GIDQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-23T21:55:39.875825Z"},"content_sha256":"ff22b22c9c2fbe8ed487859e9578f1311139953208c8a8fab1d6586b7409e105","schema_version":"1.0","event_id":"sha256:ff22b22c9c2fbe8ed487859e9578f1311139953208c8a8fab1d6586b7409e105"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2017:MBKW7J6ONST5IHSWDM67N4YKRX","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"The first frost in the Pipe Nebula","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.SR"],"primary_cat":"astro-ph.GA","authors_text":"2), (2) Universit\\\"ats-Sternwarte M\\\"unchen, 3), (3) Kapteyn Astronomical Institute, 4, (4) Leiden Observatory, 5), (5) Delft University of Technology), Gisela B. Esplugues (1, J. D. Bailey (1), Leiden University, Marco Spaans (3) ((1) Max-Planck-Institut f\\\"ur extraterrestrische Physik, Miwa Goto (1, Paola Caselli (1), Seyit Hocuk (1), Stephanie Cazaux (3, University of Groningen","submitted_at":"2017-10-16T18:00:04Z","abstract_excerpt":"Spectroscopic studies of ices in nearby star-forming regions indicate that ice mantles form on dust grains in two distinct steps, starting with polar ice formation (H2O rich) and switching to apolar ice (CO rich). We test how well the picture applies to more diffuse and quiescent clouds where the formation of the first layers of ice mantles can be witnessed. Medium-resolution near-infrared spectra are obtained toward background field stars behind the Pipe Nebula. The water ice absorption is positively detected at 3.0 micron in seven lines of sight out of 21 sources for which observed spectra a"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1710.05926","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":"2026-05-18T00:23:32Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"MRMOxpxzDwyQid4HkaBybdFTti/sT0XM60Rv2qLzo42HJLjY6JUJmPiWKrc9qHO0wgX6oZb4yqwcbErIS/9cAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-23T21:55:39.876552Z"},"content_sha256":"7d3d7c56fe6b670d916beff7a1039ee2c85d4e074e5891fc6d1d893d6cd3eec9","schema_version":"1.0","event_id":"sha256:7d3d7c56fe6b670d916beff7a1039ee2c85d4e074e5891fc6d1d893d6cd3eec9"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/MBKW7J6ONST5IHSWDM67N4YKRX/bundle.json","state_url":"https://pith.science/pith/MBKW7J6ONST5IHSWDM67N4YKRX/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/MBKW7J6ONST5IHSWDM67N4YKRX/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":"2026-05-23T21:55:39Z","links":{"resolver":"https://pith.science/pith/MBKW7J6ONST5IHSWDM67N4YKRX","bundle":"https://pith.science/pith/MBKW7J6ONST5IHSWDM67N4YKRX/bundle.json","state":"https://pith.science/pith/MBKW7J6ONST5IHSWDM67N4YKRX/state.json","well_known_bundle":"https://pith.science/.well-known/pith/MBKW7J6ONST5IHSWDM67N4YKRX/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2017:MBKW7J6ONST5IHSWDM67N4YKRX","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":"412665ee984d9bb4e5ab7e82b48d1ae9dfd168856ad901f64e79ec99cf9331e2","cross_cats_sorted":["astro-ph.SR"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-10-16T18:00:04Z","title_canon_sha256":"3185fbb19e54d4529418a8f0fbac89255ef446c5ee386af91eb9d42bd41f361a"},"schema_version":"1.0","source":{"id":"1710.05926","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1710.05926","created_at":"2026-05-18T00:23:32Z"},{"alias_kind":"arxiv_version","alias_value":"1710.05926v1","created_at":"2026-05-18T00:23:32Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1710.05926","created_at":"2026-05-18T00:23:32Z"},{"alias_kind":"pith_short_12","alias_value":"MBKW7J6ONST5","created_at":"2026-05-18T12:31:31Z"},{"alias_kind":"pith_short_16","alias_value":"MBKW7J6ONST5IHSW","created_at":"2026-05-18T12:31:31Z"},{"alias_kind":"pith_short_8","alias_value":"MBKW7J6O","created_at":"2026-05-18T12:31:31Z"}],"graph_snapshots":[{"event_id":"sha256:7d3d7c56fe6b670d916beff7a1039ee2c85d4e074e5891fc6d1d893d6cd3eec9","target":"graph","created_at":"2026-05-18T00:23:32Z","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":"Spectroscopic studies of ices in nearby star-forming regions indicate that ice mantles form on dust grains in two distinct steps, starting with polar ice formation (H2O rich) and switching to apolar ice (CO rich). We test how well the picture applies to more diffuse and quiescent clouds where the formation of the first layers of ice mantles can be witnessed. Medium-resolution near-infrared spectra are obtained toward background field stars behind the Pipe Nebula. The water ice absorption is positively detected at 3.0 micron in seven lines of sight out of 21 sources for which observed spectra a","authors_text":"2), (2) Universit\\\"ats-Sternwarte M\\\"unchen, 3), (3) Kapteyn Astronomical Institute, 4, (4) Leiden Observatory, 5), (5) Delft University of Technology), Gisela B. Esplugues (1, J. D. Bailey (1), Leiden University, Marco Spaans (3) ((1) Max-Planck-Institut f\\\"ur extraterrestrische Physik, Miwa Goto (1, Paola Caselli (1), Seyit Hocuk (1), Stephanie Cazaux (3, University of Groningen","cross_cats":["astro-ph.SR"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-10-16T18:00:04Z","title":"The first frost in the Pipe Nebula"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1710.05926","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:ff22b22c9c2fbe8ed487859e9578f1311139953208c8a8fab1d6586b7409e105","target":"record","created_at":"2026-05-18T00:23:32Z","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":"412665ee984d9bb4e5ab7e82b48d1ae9dfd168856ad901f64e79ec99cf9331e2","cross_cats_sorted":["astro-ph.SR"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2017-10-16T18:00:04Z","title_canon_sha256":"3185fbb19e54d4529418a8f0fbac89255ef446c5ee386af91eb9d42bd41f361a"},"schema_version":"1.0","source":{"id":"1710.05926","kind":"arxiv","version":1}},"canonical_sha256":"60556fa7ce6ca7d41e561b3df6f30a8de9422bffdb613505cb780630137a26fb","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"60556fa7ce6ca7d41e561b3df6f30a8de9422bffdb613505cb780630137a26fb","first_computed_at":"2026-05-18T00:23:32.427387Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:23:32.427387Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"xAeFNxunV7eWwM4T4Ufa7dgPWXUskH/USwYaaANXyknhNqZq6ITF57f8/HSO88QxXmoyLpEfbbiFNR+wpa8gAA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:23:32.427907Z","signed_message":"canonical_sha256_bytes"},"source_id":"1710.05926","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:ff22b22c9c2fbe8ed487859e9578f1311139953208c8a8fab1d6586b7409e105","sha256:7d3d7c56fe6b670d916beff7a1039ee2c85d4e074e5891fc6d1d893d6cd3eec9"],"state_sha256":"b67b93c959dddc9cec975aab1b097ef92aa74feeb12be270cdc9b84036e7c564"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"hvufZpyNh9DFOONvRz/hn/vSZvN/dyCH9NhouffaNy1M//6qpMfFAz/YUzTmDOxqXt0eL4Xxve/baLbPA19lBg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-23T21:55:39.880361Z","bundle_sha256":"efc482c73d6141e819e382583b46aa8626a2303cf4cd814ea26802e604834bd8"}}