{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2016:YKUQIBLKVZVGDM6XMPVN6Q4D6D","short_pith_number":"pith:YKUQIBLK","canonical_record":{"source":{"id":"1604.03899","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2016-04-13T18:14:30Z","cross_cats_sorted":["astro-ph.CO","astro-ph.GA"],"title_canon_sha256":"0deba8f802878f755b07d1e43272fe8e6c36bd6497b4407da5fb21a385fd3cc7","abstract_canon_sha256":"99ab41c1652d0c2e23c99afedf4d142ef201b384e5202794c0ad8e558078ec2a"},"schema_version":"1.0"},"canonical_sha256":"c2a904056aae6a61b3d763eadf4383f0f55bb708972e8ed4648dbb14e4f0d476","source":{"kind":"arxiv","id":"1604.03899","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1604.03899","created_at":"2026-05-18T01:16:12Z"},{"alias_kind":"arxiv_version","alias_value":"1604.03899v1","created_at":"2026-05-18T01:16:12Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1604.03899","created_at":"2026-05-18T01:16:12Z"},{"alias_kind":"pith_short_12","alias_value":"YKUQIBLKVZVG","created_at":"2026-05-18T12:30:53Z"},{"alias_kind":"pith_short_16","alias_value":"YKUQIBLKVZVGDM6X","created_at":"2026-05-18T12:30:53Z"},{"alias_kind":"pith_short_8","alias_value":"YKUQIBLK","created_at":"2026-05-18T12:30:53Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2016:YKUQIBLKVZVGDM6XMPVN6Q4D6D","target":"record","payload":{"canonical_record":{"source":{"id":"1604.03899","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"astro-ph.SR","submitted_at":"2016-04-13T18:14:30Z","cross_cats_sorted":["astro-ph.CO","astro-ph.GA"],"title_canon_sha256":"0deba8f802878f755b07d1e43272fe8e6c36bd6497b4407da5fb21a385fd3cc7","abstract_canon_sha256":"99ab41c1652d0c2e23c99afedf4d142ef201b384e5202794c0ad8e558078ec2a"},"schema_version":"1.0"},"canonical_sha256":"c2a904056aae6a61b3d763eadf4383f0f55bb708972e8ed4648dbb14e4f0d476","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T01:16:12.799024Z","signature_b64":"YtFje6LO599nsnNW3Plk65/yuZyLQUZS5qLYSu1QiSG0ufLNm1pQWjVli3MTMD5rV+Bvtx2f3VlCFdyl+gXsAg==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"c2a904056aae6a61b3d763eadf4383f0f55bb708972e8ed4648dbb14e4f0d476","last_reissued_at":"2026-05-18T01:16:12.798454Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T01:16:12.798454Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1604.03899","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":"2026-05-18T01:16:12Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"GkkpmbinNk/74ynl5MrlPGaXAozrGirP5EvGJ/Oq6ULAG1IunOaPODQsAeOzfFTWsth9JUvLYF4wVYfBAMBAAA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T00:59:34.096346Z"},"content_sha256":"3f1f0e08fa8bf6f182ca0994b47a0868f555ad548b802697678439c85d3485aa","schema_version":"1.0","event_id":"sha256:3f1f0e08fa8bf6f182ca0994b47a0868f555ad548b802697678439c85d3485aa"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2016:YKUQIBLKVZVGDM6XMPVN6Q4D6D","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Breaking the color-reddening degeneracy in type Ia supernovae","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":"C. Ashall, E. E. O. Ishida, M. Sasdelli, P. A. Mazzali, S. Prentice, W. Hillebrandt","submitted_at":"2016-04-13T18:14:30Z","abstract_excerpt":"A new method to study the intrinsic color and luminosity of type Ia supernovae (SNe Ia) is presented. A metric space built using principal component analysis (PCA) on spectral series SNe Ia between -12.5 and +17.5 days from B maximum is used as a set of predictors. This metric space is built to be insensitive to reddening. Hence, it does not predict the part of color excess due to dust-extinction. At the same time, the rich variability of SN Ia spectra is a good predictor of a large fraction of the intrinsic color variability. Such metric space is a good predictor of the epoch when the maximum"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1604.03899","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":"2026-05-18T01:16:12Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"Yrjk3g5uMHGO5Z1VxJdDwgd8+TY3oPSK+MoNGLlQ3Kr54l+XATDvTnF7hm1NM1FAfzTz8C0GPkKdxF/T+2rkBA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-31T00:59:34.097034Z"},"content_sha256":"1cbffa57708f2f1a2ae7f56819819bc9303b3d3d3f21ff2197867f10ddb49097","schema_version":"1.0","event_id":"sha256:1cbffa57708f2f1a2ae7f56819819bc9303b3d3d3f21ff2197867f10ddb49097"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/YKUQIBLKVZVGDM6XMPVN6Q4D6D/bundle.json","state_url":"https://pith.science/pith/YKUQIBLKVZVGDM6XMPVN6Q4D6D/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/YKUQIBLKVZVGDM6XMPVN6Q4D6D/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":"2026-05-31T00:59:34Z","links":{"resolver":"https://pith.science/pith/YKUQIBLKVZVGDM6XMPVN6Q4D6D","bundle":"https://pith.science/pith/YKUQIBLKVZVGDM6XMPVN6Q4D6D/bundle.json","state":"https://pith.science/pith/YKUQIBLKVZVGDM6XMPVN6Q4D6D/state.json","well_known_bundle":"https://pith.science/.well-known/pith/YKUQIBLKVZVGDM6XMPVN6Q4D6D/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2016:YKUQIBLKVZVGDM6XMPVN6Q4D6D","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":"99ab41c1652d0c2e23c99afedf4d142ef201b384e5202794c0ad8e558078ec2a","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":"2016-04-13T18:14:30Z","title_canon_sha256":"0deba8f802878f755b07d1e43272fe8e6c36bd6497b4407da5fb21a385fd3cc7"},"schema_version":"1.0","source":{"id":"1604.03899","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1604.03899","created_at":"2026-05-18T01:16:12Z"},{"alias_kind":"arxiv_version","alias_value":"1604.03899v1","created_at":"2026-05-18T01:16:12Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1604.03899","created_at":"2026-05-18T01:16:12Z"},{"alias_kind":"pith_short_12","alias_value":"YKUQIBLKVZVG","created_at":"2026-05-18T12:30:53Z"},{"alias_kind":"pith_short_16","alias_value":"YKUQIBLKVZVGDM6X","created_at":"2026-05-18T12:30:53Z"},{"alias_kind":"pith_short_8","alias_value":"YKUQIBLK","created_at":"2026-05-18T12:30:53Z"}],"graph_snapshots":[{"event_id":"sha256:1cbffa57708f2f1a2ae7f56819819bc9303b3d3d3f21ff2197867f10ddb49097","target":"graph","created_at":"2026-05-18T01:16:12Z","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":"A new method to study the intrinsic color and luminosity of type Ia supernovae (SNe Ia) is presented. A metric space built using principal component analysis (PCA) on spectral series SNe Ia between -12.5 and +17.5 days from B maximum is used as a set of predictors. This metric space is built to be insensitive to reddening. Hence, it does not predict the part of color excess due to dust-extinction. At the same time, the rich variability of SN Ia spectra is a good predictor of a large fraction of the intrinsic color variability. Such metric space is a good predictor of the epoch when the maximum","authors_text":"C. Ashall, E. E. O. Ishida, M. Sasdelli, P. A. Mazzali, S. Prentice, W. Hillebrandt","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":"2016-04-13T18:14:30Z","title":"Breaking the color-reddening degeneracy in type Ia supernovae"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1604.03899","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":"sha256:3f1f0e08fa8bf6f182ca0994b47a0868f555ad548b802697678439c85d3485aa","target":"record","created_at":"2026-05-18T01:16:12Z","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":"99ab41c1652d0c2e23c99afedf4d142ef201b384e5202794c0ad8e558078ec2a","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":"2016-04-13T18:14:30Z","title_canon_sha256":"0deba8f802878f755b07d1e43272fe8e6c36bd6497b4407da5fb21a385fd3cc7"},"schema_version":"1.0","source":{"id":"1604.03899","kind":"arxiv","version":1}},"canonical_sha256":"c2a904056aae6a61b3d763eadf4383f0f55bb708972e8ed4648dbb14e4f0d476","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"c2a904056aae6a61b3d763eadf4383f0f55bb708972e8ed4648dbb14e4f0d476","first_computed_at":"2026-05-18T01:16:12.798454Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T01:16:12.798454Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"YtFje6LO599nsnNW3Plk65/yuZyLQUZS5qLYSu1QiSG0ufLNm1pQWjVli3MTMD5rV+Bvtx2f3VlCFdyl+gXsAg==","signature_status":"signed_v1","signed_at":"2026-05-18T01:16:12.799024Z","signed_message":"canonical_sha256_bytes"},"source_id":"1604.03899","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:3f1f0e08fa8bf6f182ca0994b47a0868f555ad548b802697678439c85d3485aa","sha256:1cbffa57708f2f1a2ae7f56819819bc9303b3d3d3f21ff2197867f10ddb49097"],"state_sha256":"59c7cbbd07011a872fe5efb9cd66677b8a114f8d58743deb5e11951147a46d48"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"izlt2YTLmueI+yI19hcOTGYQPvCtKxXOsjhLEMsQn8zBXNseGoA8sPqoORBNMAupJgzvuLd+bFBrHsh7+UgQDA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-31T00:59:34.101052Z","bundle_sha256":"061139bf6168ba815b86a7a0ab34fb35d53c0f0cdbbd729ee5805b23e0a9322c"}}