{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2018:44AIYVPMXXZ3CKTBH6PZCTM6SE","short_pith_number":"pith:44AIYVPM","canonical_record":{"source":{"id":"1805.03972","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-05-10T13:36:18Z","cross_cats_sorted":[],"title_canon_sha256":"31042450c515bc40ead21f122c0c44902e06bfef29ed18503b8dd711771c9628","abstract_canon_sha256":"723b5bcfd105c69450080e68f9e94e06f3de93dfd89e6393a20252b418dfb92d"},"schema_version":"1.0"},"canonical_sha256":"e7008c55ecbdf3b12a613f9f914d9e910813353acbe000fc8328eb7d65cc97e0","source":{"kind":"arxiv","id":"1805.03972","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1805.03972","created_at":"2026-05-18T00:15:13Z"},{"alias_kind":"arxiv_version","alias_value":"1805.03972v1","created_at":"2026-05-18T00:15:13Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1805.03972","created_at":"2026-05-18T00:15:13Z"},{"alias_kind":"pith_short_12","alias_value":"44AIYVPMXXZ3","created_at":"2026-05-18T12:32:05Z"},{"alias_kind":"pith_short_16","alias_value":"44AIYVPMXXZ3CKTB","created_at":"2026-05-18T12:32:05Z"},{"alias_kind":"pith_short_8","alias_value":"44AIYVPM","created_at":"2026-05-18T12:32:05Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2018:44AIYVPMXXZ3CKTBH6PZCTM6SE","target":"record","payload":{"canonical_record":{"source":{"id":"1805.03972","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-05-10T13:36:18Z","cross_cats_sorted":[],"title_canon_sha256":"31042450c515bc40ead21f122c0c44902e06bfef29ed18503b8dd711771c9628","abstract_canon_sha256":"723b5bcfd105c69450080e68f9e94e06f3de93dfd89e6393a20252b418dfb92d"},"schema_version":"1.0"},"canonical_sha256":"e7008c55ecbdf3b12a613f9f914d9e910813353acbe000fc8328eb7d65cc97e0","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T00:15:13.356848Z","signature_b64":"TxYohYiDV6oa7M72WqlrsETSNIFfhqILOBqBW1qcVO8rQr1mBPdCSPCdYJFk1FEJ3rmvbRkNnno8ZHzLBqNuAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"e7008c55ecbdf3b12a613f9f914d9e910813353acbe000fc8328eb7d65cc97e0","last_reissued_at":"2026-05-18T00:15:13.356332Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T00:15:13.356332Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1805.03972","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":"2026-05-18T00:15:13Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"l7FhbF1C+SuBxt/VRSU2UWmToRYxFBqpqolcFwJFfIAEamsNs0Q2Hm3KJWmxm9Wbto/b3nBL+1YRjDm1M3ozBg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-05T16:42:15.589085Z"},"content_sha256":"3f6041166953d5474ad03f08eb1e2ad1eb26ecf3edc23d531e389d3e4365f474","schema_version":"1.0","event_id":"sha256:3f6041166953d5474ad03f08eb1e2ad1eb26ecf3edc23d531e389d3e4365f474"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2018:44AIYVPMXXZ3CKTBH6PZCTM6SE","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Recovering stellar population parameters via two full-spectrum fitting algorithms in the absence of model uncertainties","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Hongyu Li, Junqiang Ge, Michele Cappellari, Renbin Yan, Shude Mao, Youjun Lu","submitted_at":"2018-05-10T13:36:18Z","abstract_excerpt":"Using mock spectra based on Vazdekis/MILES library fitted within the wavelength region 3600-7350\\AA, we analyze the bias and scatter on the resulting physical parameters induced by the choice of fitting algorithms and observational uncertainties, but avoid effects of those model uncertainties. We consider two full-spectrum fitting codes: pPXF and STARLIGHT, in fitting for stellar population age, metallicity, mass-to-light ratio, and dust extinction. With pPXF we find that both the bias in the population parameters and the scatter in the recovered logarithmic values follows the expected trend. "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1805.03972","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":"2026-05-18T00:15:13Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"WvKbWK5JQaGNbAj8JsOm8d1rsJiw/+c090Y3m4vjCeZWpr2iaFehK1E/P7jPSEc14yuNXEpRGIQ9KS3niGRkDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-05T16:42:15.589442Z"},"content_sha256":"47d86d5fde484d63aacb47b3e8faba1d18529d8b43aa2ac22f79425ed30d4ff9","schema_version":"1.0","event_id":"sha256:47d86d5fde484d63aacb47b3e8faba1d18529d8b43aa2ac22f79425ed30d4ff9"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/44AIYVPMXXZ3CKTBH6PZCTM6SE/bundle.json","state_url":"https://pith.science/pith/44AIYVPMXXZ3CKTBH6PZCTM6SE/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/44AIYVPMXXZ3CKTBH6PZCTM6SE/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":"2026-06-05T16:42:15Z","links":{"resolver":"https://pith.science/pith/44AIYVPMXXZ3CKTBH6PZCTM6SE","bundle":"https://pith.science/pith/44AIYVPMXXZ3CKTBH6PZCTM6SE/bundle.json","state":"https://pith.science/pith/44AIYVPMXXZ3CKTBH6PZCTM6SE/state.json","well_known_bundle":"https://pith.science/.well-known/pith/44AIYVPMXXZ3CKTBH6PZCTM6SE/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2018:44AIYVPMXXZ3CKTBH6PZCTM6SE","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":"723b5bcfd105c69450080e68f9e94e06f3de93dfd89e6393a20252b418dfb92d","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-05-10T13:36:18Z","title_canon_sha256":"31042450c515bc40ead21f122c0c44902e06bfef29ed18503b8dd711771c9628"},"schema_version":"1.0","source":{"id":"1805.03972","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1805.03972","created_at":"2026-05-18T00:15:13Z"},{"alias_kind":"arxiv_version","alias_value":"1805.03972v1","created_at":"2026-05-18T00:15:13Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1805.03972","created_at":"2026-05-18T00:15:13Z"},{"alias_kind":"pith_short_12","alias_value":"44AIYVPMXXZ3","created_at":"2026-05-18T12:32:05Z"},{"alias_kind":"pith_short_16","alias_value":"44AIYVPMXXZ3CKTB","created_at":"2026-05-18T12:32:05Z"},{"alias_kind":"pith_short_8","alias_value":"44AIYVPM","created_at":"2026-05-18T12:32:05Z"}],"graph_snapshots":[{"event_id":"sha256:47d86d5fde484d63aacb47b3e8faba1d18529d8b43aa2ac22f79425ed30d4ff9","target":"graph","created_at":"2026-05-18T00:15:13Z","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":"Using mock spectra based on Vazdekis/MILES library fitted within the wavelength region 3600-7350\\AA, we analyze the bias and scatter on the resulting physical parameters induced by the choice of fitting algorithms and observational uncertainties, but avoid effects of those model uncertainties. We consider two full-spectrum fitting codes: pPXF and STARLIGHT, in fitting for stellar population age, metallicity, mass-to-light ratio, and dust extinction. With pPXF we find that both the bias in the population parameters and the scatter in the recovered logarithmic values follows the expected trend. ","authors_text":"Hongyu Li, Junqiang Ge, Michele Cappellari, Renbin Yan, Shude Mao, Youjun Lu","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-05-10T13:36:18Z","title":"Recovering stellar population parameters via two full-spectrum fitting algorithms in the absence of model uncertainties"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1805.03972","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":"sha256:3f6041166953d5474ad03f08eb1e2ad1eb26ecf3edc23d531e389d3e4365f474","target":"record","created_at":"2026-05-18T00:15:13Z","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":"723b5bcfd105c69450080e68f9e94e06f3de93dfd89e6393a20252b418dfb92d","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.GA","submitted_at":"2018-05-10T13:36:18Z","title_canon_sha256":"31042450c515bc40ead21f122c0c44902e06bfef29ed18503b8dd711771c9628"},"schema_version":"1.0","source":{"id":"1805.03972","kind":"arxiv","version":1}},"canonical_sha256":"e7008c55ecbdf3b12a613f9f914d9e910813353acbe000fc8328eb7d65cc97e0","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"e7008c55ecbdf3b12a613f9f914d9e910813353acbe000fc8328eb7d65cc97e0","first_computed_at":"2026-05-18T00:15:13.356332Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T00:15:13.356332Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"TxYohYiDV6oa7M72WqlrsETSNIFfhqILOBqBW1qcVO8rQr1mBPdCSPCdYJFk1FEJ3rmvbRkNnno8ZHzLBqNuAA==","signature_status":"signed_v1","signed_at":"2026-05-18T00:15:13.356848Z","signed_message":"canonical_sha256_bytes"},"source_id":"1805.03972","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:3f6041166953d5474ad03f08eb1e2ad1eb26ecf3edc23d531e389d3e4365f474","sha256:47d86d5fde484d63aacb47b3e8faba1d18529d8b43aa2ac22f79425ed30d4ff9"],"state_sha256":"9b95df82e69a397a0aa00fb61d39330ab44e6cbd4637b7ca3d9cffa090c6fe4d"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"t0Rtg/SQDV0eyN6PFPW33QgP2q7PZ0gy0PQqBCd8pxBg/ML7f1YRNv7pV0/77Vu2SiVRtZWLvI8jeOXA1nmPCg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-05T16:42:15.591327Z","bundle_sha256":"becbcfa98bff6dba1ffba3371ffaa86bd40e3f8e5eb39ab53e9baa799f231b3e"}}