{"paper":{"title":"Observational Constraints on the Nature of the Dark Energy: First Cosmological Results from the ESSENCE Supernova Survey","license":"","headline":"","cross_cats":[],"primary_cat":"astro-ph","authors_text":"A. C. Becker, A. Clocchiatti, A. Conley, A. Garg, A. G. Riess, A. Miceli, A. Rest, A. V. Filippenko, A. Zenteno, B. Leibundgut, B. P. Schmidt, C. Aguilera, C. W. Stubbs, G. Miknaitis, G. Narayan, G. Pignata, J. L. Prieto, J. L. Tonry, J. Sollerman, J. Spyromilio, J. W. Blackman, K. Krisciunas, M. E. Salvo, M. Hicken, N. B. Suntzeff, P. Challis, P. M. Garnavich, R. Covarrubias, R. C. Smith, R. J. Foley, R. P. Kirshner, S. Blondin, S. Jha, T. Matheson, T. M. Davis, W. Li, W. M. Wood-Vasey","submitted_at":"2007-01-02T21:01:42Z","abstract_excerpt":"We present constraints on the dark energy equation-of-state parameter, w=P/(rho c^2), using 60 Type Ia supernovae (SNe Ia) from the ESSENCE supernova survey. We derive a set of constraints on the nature of the dark energy assuming a flat Universe. By including constraints on (Omega_M, w) from baryon acoustic oscillations, we obtain a value for a static equation-of-state parameter w=-1.05^{+0.13}_{-0.12} (stat; 1 sigma) +- 0.11 (sys) and Omega_M=0.274^{+0.033}_{-0.020} (stat; 1 sigma) with a best-fit chi^2/DoF of 0.96. These results are consistent with those reported by the SuperNova Legacy Sur"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"astro-ph/0701041","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/0701041/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"}