Séminaire / Seminar GReCO |
| « Confronting braneworld models of dark energy with supernova and other datasets » |
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U. Alam |
| Braneworld cosmology has several attractive and distinctive features. In this study we compare the predictions of braneworld models to two recently released supernova data sets: the `Gold'' data (Riess et al, 2004) and the data from the Supernova Legacy Survey (SNLS) (Astier et al, 2005) as well as the recent discovery of the baryon acoustic peak in the Sloan Digital Sky Survey (Eisenstein et al, 2005), and CMB results from WMAP3. Braneworld models satisfy both sets of SNe data. Models with w_0 less than or equal to -1 show very good agreement with data for values of the matter density bounded from below: Omega_m greater than or equal to 0.25 (Gold) and Omega_m greater than or equal to 0.2 (SNLS). On the other hand models with w_0 greater than or equal to -1 show excellent agreement with data for values of the matter density which are bounded from above: Omega_m less than or equal to 0.45 (Gold) and Omega_m less than or equal to 0.35 (SNLS). The DGP model is excluded at 2 sigma by joint analysis using SNLS SNe data but is accepted at the same level by the joint analysis using Gold SNe data. |
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lundi 25 septembre 2006 - 11:00 Salle des séminaires Évry Schatzman Institut d'Astrophysique de Paris |
| Pages web du séminaire / Seminar's webpage |