158 articles – 1987 Notices  [english version]
 HAL : in2p3-00025162, version 1
 arXiv : astro-ph/0510447
 Astronomy and Astrophysics 447 (2006) 31-48
 The Supernova Legacy Survey: Measurement of $\Omega_M$, $\Omega_\Lambda$ and w from the First Year Data Set
 SNLS Collaboration(s)
 (2006)
 We present distance measurements to 71 high redshift type Ia supernovae discovered during the first year of the 5-year Supernova Legacy Survey (SNLS). These events were detected and their multi-color light-curves measured using the MegaPrime/MegaCam instrument at the Canada-France-Hawaii Telescope (CFHT), by repeatedly imaging four one-square degree fields in four bands. Follow-up spectroscopy was performed at the VLT, Gemini and Keck telescopes to confirm the nature of the supernovae and to measure their redshift. With this data set, we have built a Hubble diagram extending to z=1, with all distance measurements involving at least two bands. Systematic uncertainties are evaluated making use of the multi-band photometry obtained at CFHT. Cosmological fits to this first year SNLS Hubble diagram give the following results : Omega_M = 0.263 +/- 0.042(stat) +/- 0.032(sys) for a flat LambdaCDM model; and w = -1.023 +/- 0.090(stat) +/- 0.054(sys) for a flat cosmology with constant equation of state w when combined with the constraint from the recent Sloan Digital Sky Survey measurement of baryon acoustic oscillations.
 Thème(s) : Physique/Astrophysique/Cosmologie et astrophysique extra-galactiquePlanète et Univers/Astrophysique
 Mot(s)-clé(s) : supernovae: general – cosmology: observations
 Lien vers le texte intégral : http://fr.arXiv.org/abs/astro-ph/0510447
 in2p3-00025162, version 1 http://hal.in2p3.fr/in2p3-00025162 oai:hal.in2p3.fr:in2p3-00025162 Contributeur : Simone Lantz <> Soumis le : Samedi 9 Juin 2007, 15:58:30 Dernière modification le : Samedi 9 Juin 2007, 16:03:34