{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2010:A4LCIZGHMJALLJIOEIVFKUKBZF","short_pith_number":"pith:A4LCIZGH","canonical_record":{"source":{"id":"1008.1014","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2010-08-05T16:03:40Z","cross_cats_sorted":["astro-ph.CO","astro-ph.GA"],"title_canon_sha256":"186b32b6d211182cb7a894d9f625c1f75367f8f736c3911c2952b4d3f911d6fd","abstract_canon_sha256":"cdc9c872ea9490b5040d1c37cf94346e98cefee35cef8bfd9ff825fd0b7366e8"},"schema_version":"1.0"},"canonical_sha256":"07162464c76240b5a50e222a555141c96a0b03d5fc5ef0a29e05cc9a2cd8775b","source":{"kind":"arxiv","id":"1008.1014","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1008.1014","created_at":"2026-05-18T04:42:33Z"},{"alias_kind":"arxiv_version","alias_value":"1008.1014v2","created_at":"2026-05-18T04:42:33Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1008.1014","created_at":"2026-05-18T04:42:33Z"},{"alias_kind":"pith_short_12","alias_value":"A4LCIZGHMJAL","created_at":"2026-05-18T12:26:05Z"},{"alias_kind":"pith_short_16","alias_value":"A4LCIZGHMJALLJIO","created_at":"2026-05-18T12:26:05Z"},{"alias_kind":"pith_short_8","alias_value":"A4LCIZGH","created_at":"2026-05-18T12:26:05Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2010:A4LCIZGHMJALLJIOEIVFKUKBZF","target":"record","payload":{"canonical_record":{"source":{"id":"1008.1014","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2010-08-05T16:03:40Z","cross_cats_sorted":["astro-ph.CO","astro-ph.GA"],"title_canon_sha256":"186b32b6d211182cb7a894d9f625c1f75367f8f736c3911c2952b4d3f911d6fd","abstract_canon_sha256":"cdc9c872ea9490b5040d1c37cf94346e98cefee35cef8bfd9ff825fd0b7366e8"},"schema_version":"1.0"},"canonical_sha256":"07162464c76240b5a50e222a555141c96a0b03d5fc5ef0a29e05cc9a2cd8775b","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T04:42:33.454336Z","signature_b64":"7i6SyPRfNZ8RIxwLq6MXv761PqIbdOXhwNHy3BMX3k9+pjpN8oqnQrZfzxA3J74q7vUjXzfVARxue1eQFceQCA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"07162464c76240b5a50e222a555141c96a0b03d5fc5ef0a29e05cc9a2cd8775b","last_reissued_at":"2026-05-18T04:42:33.452333Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T04:42:33.452333Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1008.1014","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T04:42:33Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"shd5wuuVxb9IPojnP4jRTjLQQVnuKePILi8JIHWN8MfhCtM1cy3g5RMVV69nHOCGSyiHKFOW9jev2O7bi2iWBQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T23:12:32.136486Z"},"content_sha256":"33215c58dc7f14f93fb4c7fe5a19d5685ec17d827783c3edc308164092019cb3","schema_version":"1.0","event_id":"sha256:33215c58dc7f14f93fb4c7fe5a19d5685ec17d827783c3edc308164092019cb3"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2010:A4LCIZGHMJALLJIOEIVFKUKBZF","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"The Slope of the Upper End of the IMF and the Upper Mass Limit: An Observer's Perspective","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.CO","astro-ph.GA"],"primary_cat":"astro-ph.SR","authors_text":"Philip Massey","submitted_at":"2010-08-05T16:03:40Z","abstract_excerpt":"There are various ways of measuring the slope of the upper end of the IMF. Arguably the most direct of these is to place stars on the H-R diagram and compare their positions with stellar evolutionary models. Even so, the masses one infers from this depend upon the exact methodology used. I briefly discusssome of the caveats and go through a brief error analysis. I conclude that the current data suggest that the IMF slopes are the same to within the errors. Similarly the determination of the upper mass \"limit\" is dependent upon how well one can determine the masses of the most massive stars wit"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1008.1014","kind":"arxiv","version":2},"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":"2026-05-18T04:42:33Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"6ykG/Cb3706YVk4TADacPrbm/cPsTFXo+WuZPMkZQbxx5Wd2n5DeEBEWjbsqN4zVOJlbMuYxlgb2duCb8yl0DQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-25T23:12:32.137157Z"},"content_sha256":"bc097a8d5eaaf2159609bf92fca6faa60470d40b33502c1b2116aa891d4144ed","schema_version":"1.0","event_id":"sha256:bc097a8d5eaaf2159609bf92fca6faa60470d40b33502c1b2116aa891d4144ed"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/A4LCIZGHMJALLJIOEIVFKUKBZF/bundle.json","state_url":"https://pith.science/pith/A4LCIZGHMJALLJIOEIVFKUKBZF/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/A4LCIZGHMJALLJIOEIVFKUKBZF/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":"2026-05-25T23:12:32Z","links":{"resolver":"https://pith.science/pith/A4LCIZGHMJALLJIOEIVFKUKBZF","bundle":"https://pith.science/pith/A4LCIZGHMJALLJIOEIVFKUKBZF/bundle.json","state":"https://pith.science/pith/A4LCIZGHMJALLJIOEIVFKUKBZF/state.json","well_known_bundle":"https://pith.science/.well-known/pith/A4LCIZGHMJALLJIOEIVFKUKBZF/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2010:A4LCIZGHMJALLJIOEIVFKUKBZF","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":"cdc9c872ea9490b5040d1c37cf94346e98cefee35cef8bfd9ff825fd0b7366e8","cross_cats_sorted":["astro-ph.CO","astro-ph.GA"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2010-08-05T16:03:40Z","title_canon_sha256":"186b32b6d211182cb7a894d9f625c1f75367f8f736c3911c2952b4d3f911d6fd"},"schema_version":"1.0","source":{"id":"1008.1014","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1008.1014","created_at":"2026-05-18T04:42:33Z"},{"alias_kind":"arxiv_version","alias_value":"1008.1014v2","created_at":"2026-05-18T04:42:33Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1008.1014","created_at":"2026-05-18T04:42:33Z"},{"alias_kind":"pith_short_12","alias_value":"A4LCIZGHMJAL","created_at":"2026-05-18T12:26:05Z"},{"alias_kind":"pith_short_16","alias_value":"A4LCIZGHMJALLJIO","created_at":"2026-05-18T12:26:05Z"},{"alias_kind":"pith_short_8","alias_value":"A4LCIZGH","created_at":"2026-05-18T12:26:05Z"}],"graph_snapshots":[{"event_id":"sha256:bc097a8d5eaaf2159609bf92fca6faa60470d40b33502c1b2116aa891d4144ed","target":"graph","created_at":"2026-05-18T04:42:33Z","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":"There are various ways of measuring the slope of the upper end of the IMF. Arguably the most direct of these is to place stars on the H-R diagram and compare their positions with stellar evolutionary models. Even so, the masses one infers from this depend upon the exact methodology used. I briefly discusssome of the caveats and go through a brief error analysis. I conclude that the current data suggest that the IMF slopes are the same to within the errors. Similarly the determination of the upper mass \"limit\" is dependent upon how well one can determine the masses of the most massive stars wit","authors_text":"Philip Massey","cross_cats":["astro-ph.CO","astro-ph.GA"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2010-08-05T16:03:40Z","title":"The Slope of the Upper End of the IMF and the Upper Mass Limit: An Observer's Perspective"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1008.1014","kind":"arxiv","version":2},"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":"sha256:33215c58dc7f14f93fb4c7fe5a19d5685ec17d827783c3edc308164092019cb3","target":"record","created_at":"2026-05-18T04:42:33Z","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":"cdc9c872ea9490b5040d1c37cf94346e98cefee35cef8bfd9ff825fd0b7366e8","cross_cats_sorted":["astro-ph.CO","astro-ph.GA"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2010-08-05T16:03:40Z","title_canon_sha256":"186b32b6d211182cb7a894d9f625c1f75367f8f736c3911c2952b4d3f911d6fd"},"schema_version":"1.0","source":{"id":"1008.1014","kind":"arxiv","version":2}},"canonical_sha256":"07162464c76240b5a50e222a555141c96a0b03d5fc5ef0a29e05cc9a2cd8775b","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"07162464c76240b5a50e222a555141c96a0b03d5fc5ef0a29e05cc9a2cd8775b","first_computed_at":"2026-05-18T04:42:33.452333Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T04:42:33.452333Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"7i6SyPRfNZ8RIxwLq6MXv761PqIbdOXhwNHy3BMX3k9+pjpN8oqnQrZfzxA3J74q7vUjXzfVARxue1eQFceQCA==","signature_status":"signed_v1","signed_at":"2026-05-18T04:42:33.454336Z","signed_message":"canonical_sha256_bytes"},"source_id":"1008.1014","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:33215c58dc7f14f93fb4c7fe5a19d5685ec17d827783c3edc308164092019cb3","sha256:bc097a8d5eaaf2159609bf92fca6faa60470d40b33502c1b2116aa891d4144ed"],"state_sha256":"a770997e1b2a9dbe26e3fc0346d470661a4825a508b5903231eef03484bc02b0"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"QeyVrp41NDwLZm47CLOVyG60mw6FvPIQ8v6RwCIebaLk0QbRC80vXcFaoAnzt2d24ihrlof30Gsdpa8Jjos3Dw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-25T23:12:32.140444Z","bundle_sha256":"1c64b4155ea670b676c25f7a578c36f24612af5d7dcd82b67446c034ca2533ef"}}