{"paper":{"title":"Quantitative comparison between Type Ia supernova spectra at low and high redshifts: A case study","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"A. Conley, A. G. Kim, A. Goobar, A. L. Spadafora, B. C. Lee, C. Lidman, D. A. Howell, D. E. Groom, E. Smith, G. Aldering, G. Blanc, G. Folatelli, G. Garavini, G. Goldhaber, G. Sainton, I. Hook, J. Bronder, J. Mendez, J. Raux, K. Motohara, K. Schahmaneche, L. Wang, M. Doi, M. Kowalski, M. S. Burns, N. A. Walton, N. Kashikawa, N. Kuznetsova, N. Regnault, N. Yasuda. The Supernova Cosmology Project, P. Antilogus, P. Astier, P. E. Nugent, P. Ruiz-Lapuente, R. Amanullah, R. C. Thomas, R. Gibbons, R. Pain, R. Quimby, S. E. Deustua, S. Fabbro, S. Nobili, S. Perlmutter, T. Morokuma, V. Fadeyev, V. Stanishev, W. M. Wood-Vasey","submitted_at":"2007-03-24T10:09:59Z","abstract_excerpt":"We develop a method to measure the strength of the absorption features in Type Ia supernova (SN Ia) spectra and use it to make a quantitative comparison between the spectra of Type Ia supernovae at low and high redshifts. In this case study, we apply the method to 12 high-redshift (0.212 < z < 0.912) SNe Ia observed by the Supernova Cosmology Project . Through measurements of the strengths of these features and of the blueshift of the absorption minimum in Ca II H&K, we show that the spectra of the high-redshift SNe Ia are quantitatively similar to spectra of nearby SNe Ia (z < 0.15). One supe"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0703629","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/astro-ph/0703629/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"}