{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2021:6ME7AWY5I2IR5JXQMR4S2CFCJK","short_pith_number":"pith:6ME7AWY5","canonical_record":{"source":{"id":"2104.06431","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.GA","submitted_at":"2021-04-13T18:12:45Z","cross_cats_sorted":[],"title_canon_sha256":"66d7b909898c6c9e5655a962ef4c6ef7a7ecc92b52d6504748dea98997183ecd","abstract_canon_sha256":"5a95ebe3693bd9faa1651423e65e7a35107efc4f134f579436369f6aaee9bc63"},"schema_version":"1.0"},"canonical_sha256":"f309f05b1d46911ea6f064792d08a24a8f533b168c5f87933e47922669242aa5","source":{"kind":"arxiv","id":"2104.06431","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2104.06431","created_at":"2026-07-05T02:53:41Z"},{"alias_kind":"arxiv_version","alias_value":"2104.06431v1","created_at":"2026-07-05T02:53:41Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2104.06431","created_at":"2026-07-05T02:53:41Z"},{"alias_kind":"pith_short_12","alias_value":"6ME7AWY5I2IR","created_at":"2026-07-05T02:53:41Z"},{"alias_kind":"pith_short_16","alias_value":"6ME7AWY5I2IR5JXQ","created_at":"2026-07-05T02:53:41Z"},{"alias_kind":"pith_short_8","alias_value":"6ME7AWY5","created_at":"2026-07-05T02:53:41Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2021:6ME7AWY5I2IR5JXQMR4S2CFCJK","target":"record","payload":{"canonical_record":{"source":{"id":"2104.06431","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.GA","submitted_at":"2021-04-13T18:12:45Z","cross_cats_sorted":[],"title_canon_sha256":"66d7b909898c6c9e5655a962ef4c6ef7a7ecc92b52d6504748dea98997183ecd","abstract_canon_sha256":"5a95ebe3693bd9faa1651423e65e7a35107efc4f134f579436369f6aaee9bc63"},"schema_version":"1.0"},"canonical_sha256":"f309f05b1d46911ea6f064792d08a24a8f533b168c5f87933e47922669242aa5","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-05T02:53:41.147370Z","signature_b64":"RTaKL4eev1Bf2US9XpAFnpDBt/y1w9AJxctKyqgWst8EF0Tq9jvDUZXgzo7maKADPEAbbQnCnQs8psInz2BCCw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"f309f05b1d46911ea6f064792d08a24a8f533b168c5f87933e47922669242aa5","last_reissued_at":"2026-07-05T02:53:41.146962Z","signature_status":"signed_v1","first_computed_at":"2026-07-05T02:53:41.146962Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2104.06431","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":"2026-07-05T02:53:41Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"+XMnTHuYXrE7Mm7h/ROgCfv8AlZgpvfLdRNlQXiKlnm+NJWgLkCe06KxVXmHodUojJk1jnIq2iT9e4x2yrQ+Bg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-03T15:46:32.748139Z"},"content_sha256":"ff6d60c1b226476d39570ef349ca4983ccd02668f71e90100ab479463848373a","schema_version":"1.0","event_id":"sha256:ff6d60c1b226476d39570ef349ca4983ccd02668f71e90100ab479463848373a"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2021:6ME7AWY5I2IR5JXQMR4S2CFCJK","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Identification of prestellar cores in high-mass star forming clumps via $\\rm H_2D^+$ observations with ALMA","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"A. Giannetti, D. Colombo, D. R. G. Schleicher, E. Redaelli, F. Wyrowski, G. Sabatini, P. Caselli, S. Bovino","submitted_at":"2021-04-13T18:12:45Z","abstract_excerpt":"Context. The different theoretical models concerning the formation of high-mass stars make distinct predictions regarding their progenitors, i.e. the high-mass prestellar cores. However, so far no conclusive observation of such objects has been made.\n  Aims. We aim to study the very early stages of high-mass star formation in two infrared-dark, massive clumps, to identify the core population that they harbour.\n  Methods. We obtained ALMA observations of continuum emission at 0.8mm and of the ortho-$\\rm H_2D^+$ transition at 372GHz towards the two clumps. We use the SCIMES algorithm to identify"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2104.06431","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/2104.06431/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":"2026-07-05T02:53:41Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"BzaitFf92Gh7ybCY7Nk0mNRN0VAdZwxR5rz8kYqAR0LEVgyOHKBl8l+EyPuQ4QqohqOSzDMlDXc7vHZ4nj0aDA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-03T15:46:32.748524Z"},"content_sha256":"9ef098d1363d27a7d07c5ff6d088426753cff15528fd5a509da7864a91567fed","schema_version":"1.0","event_id":"sha256:9ef098d1363d27a7d07c5ff6d088426753cff15528fd5a509da7864a91567fed"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/6ME7AWY5I2IR5JXQMR4S2CFCJK/bundle.json","state_url":"https://pith.science/pith/6ME7AWY5I2IR5JXQMR4S2CFCJK/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/6ME7AWY5I2IR5JXQMR4S2CFCJK/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":"2026-08-03T15:46:32Z","links":{"resolver":"https://pith.science/pith/6ME7AWY5I2IR5JXQMR4S2CFCJK","bundle":"https://pith.science/pith/6ME7AWY5I2IR5JXQMR4S2CFCJK/bundle.json","state":"https://pith.science/pith/6ME7AWY5I2IR5JXQMR4S2CFCJK/state.json","well_known_bundle":"https://pith.science/.well-known/pith/6ME7AWY5I2IR5JXQMR4S2CFCJK/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2021:6ME7AWY5I2IR5JXQMR4S2CFCJK","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":"5a95ebe3693bd9faa1651423e65e7a35107efc4f134f579436369f6aaee9bc63","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.GA","submitted_at":"2021-04-13T18:12:45Z","title_canon_sha256":"66d7b909898c6c9e5655a962ef4c6ef7a7ecc92b52d6504748dea98997183ecd"},"schema_version":"1.0","source":{"id":"2104.06431","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2104.06431","created_at":"2026-07-05T02:53:41Z"},{"alias_kind":"arxiv_version","alias_value":"2104.06431v1","created_at":"2026-07-05T02:53:41Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2104.06431","created_at":"2026-07-05T02:53:41Z"},{"alias_kind":"pith_short_12","alias_value":"6ME7AWY5I2IR","created_at":"2026-07-05T02:53:41Z"},{"alias_kind":"pith_short_16","alias_value":"6ME7AWY5I2IR5JXQ","created_at":"2026-07-05T02:53:41Z"},{"alias_kind":"pith_short_8","alias_value":"6ME7AWY5","created_at":"2026-07-05T02:53:41Z"}],"graph_snapshots":[{"event_id":"sha256:9ef098d1363d27a7d07c5ff6d088426753cff15528fd5a509da7864a91567fed","target":"graph","created_at":"2026-07-05T02:53:41Z","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/2104.06431/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Context. The different theoretical models concerning the formation of high-mass stars make distinct predictions regarding their progenitors, i.e. the high-mass prestellar cores. However, so far no conclusive observation of such objects has been made.\n  Aims. We aim to study the very early stages of high-mass star formation in two infrared-dark, massive clumps, to identify the core population that they harbour.\n  Methods. We obtained ALMA observations of continuum emission at 0.8mm and of the ortho-$\\rm H_2D^+$ transition at 372GHz towards the two clumps. We use the SCIMES algorithm to identify","authors_text":"A. Giannetti, D. Colombo, D. R. G. Schleicher, E. Redaelli, F. Wyrowski, G. Sabatini, P. Caselli, S. Bovino","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.GA","submitted_at":"2021-04-13T18:12:45Z","title":"Identification of prestellar cores in high-mass star forming clumps via $\\rm H_2D^+$ observations with ALMA"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2104.06431","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:ff6d60c1b226476d39570ef349ca4983ccd02668f71e90100ab479463848373a","target":"record","created_at":"2026-07-05T02:53:41Z","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":"5a95ebe3693bd9faa1651423e65e7a35107efc4f134f579436369f6aaee9bc63","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"astro-ph.GA","submitted_at":"2021-04-13T18:12:45Z","title_canon_sha256":"66d7b909898c6c9e5655a962ef4c6ef7a7ecc92b52d6504748dea98997183ecd"},"schema_version":"1.0","source":{"id":"2104.06431","kind":"arxiv","version":1}},"canonical_sha256":"f309f05b1d46911ea6f064792d08a24a8f533b168c5f87933e47922669242aa5","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"f309f05b1d46911ea6f064792d08a24a8f533b168c5f87933e47922669242aa5","first_computed_at":"2026-07-05T02:53:41.146962Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T02:53:41.146962Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"RTaKL4eev1Bf2US9XpAFnpDBt/y1w9AJxctKyqgWst8EF0Tq9jvDUZXgzo7maKADPEAbbQnCnQs8psInz2BCCw==","signature_status":"signed_v1","signed_at":"2026-07-05T02:53:41.147370Z","signed_message":"canonical_sha256_bytes"},"source_id":"2104.06431","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:ff6d60c1b226476d39570ef349ca4983ccd02668f71e90100ab479463848373a","sha256:9ef098d1363d27a7d07c5ff6d088426753cff15528fd5a509da7864a91567fed"],"state_sha256":"77e1900a7531c4d9e22215fe3880cd1431d0459cee13f18d4fd2c31c6f52f1ae"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"RVUi6/4DajgVxfn8s/1jqG6V01Oa+j0rPp2A5EcJz4A2SbkedrLj6+BAPD9D+Yl6DG88n0KMLm6kb8CdYsoeAg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-03T15:46:32.751185Z","bundle_sha256":"2ec7bd1afcb5e29d7670113986bc582f3d3fa4d828d968cde31b406b02bfca6d"}}