6 code implementations • 16 Jan 2014 • M. Betoule, R. Kessler, J. Guy, J. Mosher, D. Hardin, R. Biswas, P. Astier, P. El-Hage, M. Konig, S. Kuhlmann, J. Marriner, R. Pain, N. Regnault, C. Balland, B. A. Bassett, P. J. Brown, H. Campbell, R. G. Carlberg, F. Cellier-Holzem, D. Cinabro, A. Conley, C. B. D'Andrea, D. L. Depoy, M. Doi, R. S. Ellis, S. Fabbro, A. V. Filippenko, R. J. Foley, J. A. Frieman, D. Fouchez, L. Galbany, A. Goobar, R. R. Gupta, G. J. Hill, R. Hlozek, C. J. Hogan, I. M. Hook, D. A. Howell, S. W. Jha, L. Le Guillou, G. Leloudas, C. Lidman, J. L. Marshall, A. Möller, A. M. Mourão, J. Neveu, R. Nichol, M. D. Olmstead, N. Palanque-Delabrouille, S. Perlmutter, J. L. Prieto, C. J. Pritchet, M. Richmond, A. G. Riess, V. Ruhlmann-Kleider, M. Sako, K. Schahmaneche, D. P. Schneider, M. Smith, J. Sollerman, M. Sullivan, N. A. Walton, C. J. Wheeler
We have followed the methods and assumptions of the SNLS 3-year data analysis except for the following important improvements: 1) the addition of the full SDSS-II spectroscopically-confirmed SN Ia sample in both the training of the SALT2 light curve model and in the Hubble diagram analysis (\nsdssc SNe), 2) inter-calibration of the SNLS and SDSS surveys and reduced systematic uncertainties in the photometric calibration, performed blindly with respect to the cosmology analysis, and 3) a thorough investigation of systematic errors associated with the SALT2 modeling of SN Ia light-curves.
Cosmology and Nongalactic Astrophysics
2 code implementations • 26 Aug 2009 • N. Regnault, A. Conley, J. Guy, M. Sullivan, J. -C. Cuillandre, P. Astier, C. Balland, S. Basa, R. G. Carlberg, D. Fouchez, D. Hardin, I. M. Hook, D. A. Howell, R. Pain, K. Perrett, C. J. Pritchet
The photometric calibration of the SNLS requires obtaining a uniform response across the imager, calibrating the science field stars in each survey band (SDSS-like ugriz bands) with respect to standards with known flux in the same bands, and binding the calibration to the UBVRI Landolt standards used to calibrate the nearby SNe from the literature necessary to produce cosmological constraints.
Instrumentation and Methods for Astrophysics Cosmology and Nongalactic Astrophysics
2 code implementations • 7 Apr 2009 • G. Bazin, N. Palanque-Delabrouille, J. Rich, V. Ruhlmann-Kleider, E. Aubourg, L. Le Guillou, P. Astier, C. Balland, S. Basa, R. G. Carlberg, A. Conley, D. Fouchez, J. Guy, D. Hardin, I. M. Hook, D. A. Howell, R. Pain, K. Perrett, C. J. Pritchet, N. Regnault, M. Sullivan, P. Antilogus, V. Arsenijevic, S. Baumont, S. Fabbro, J. Le Du, C. Lidman, M. Mouchet, A. Mourão, E. S. Walker
Using spectroscopy and light-curve fitting to discriminate against SNIa, we find a sample of 117 core-collapse supernova candidates with redshifts $z<0. 4$ (median redshift of 0. 29) and measure their rate to be larger than the type Ia supernova rate by a factor $4. 5\pm0. 8(stat.)
Cosmology and Nongalactic Astrophysics
1 code implementation • 28 Oct 2008 • M. Kilbinger, K. Benabed, J. Guy, P. Astier, I. Tereno, L. Fu, D. Wraith, J. Coupon, Y. Mellier, C. Balland, F. R. Bouchet, T. Hamana, D. Hardin, H. J. McCracken, R. Pain, N. Regnault, M. Schultheis, H. Yahagi
We combine measurements of weak gravitational lensing from the CFHTLS-Wide survey, supernovae Ia from CFHT SNLS and CMB anisotropies from WMAP5 to obtain joint constraints on cosmological parameters, in particular, the dark energy equation of state parameter w. We assess the influence of systematics in the data on the results and look for possible correlations with cosmological parameters.