The Supernova Legacy Survey 3-year sample: Type Ia supernovae photometric distances and cosmological constraints⋆,⋆⋆
LPNHE, CNRS/IN2P3, Université Pierre et Marie Curie Paris 6, Université
Denis Diderot Paris 7, 4 place
Paris Cedex 05,
2 Department of Physics (Astrophysics), University of Oxford, DWB, Keble Road, Oxford OX1 3RH, UK
3 Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309-0391, USA
4 Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto ON M5S 3H4, Canada
5 Université Paris 11, 91405 Orsay, France
6 LAM, CNRS, BP8, Traverse du Siphon, 13376 Marseille Cedex 12, France
7 CPPM, CNRS-IN2P3 and Université Aix-Marseille II, Case 907, 13288 Marseille Cedex 9, France
8 INAF – Osservatorio Astronomico di Roma, via Frascati 33, 00040 Monteporzio (RM), Italy
9 Las Cumbres Observatory Global Telescope Network, 6740 Cortona Dr., Suite 102, Goleta, CA 93117, USA
10 Department of Physics, University of California, Santa Barbara, Broida Hall, Mail Code 9530, Santa Barbara, CA 93106-9530, USA
11 CEA, Centre de Saclay, Irfu/SPP, 91191 Gif-sur-Yvette, France
12 Network Information Operations, DRDC-Ottawa, 3701 Carling Avenue, Ottawa, ON, K1A 0Z4, Canada
13 Department of Physics and Astronomy, University of Victoria, PO Box 3055 STN CSC, Victoria BC V8T 1M8, Canada
14 LPSC, CNRS-IN2P3, 53 rue des Martyrs, 38026 Grenoble Cedex, France
15 Department of Astrophysics, California Institute of Technology, MS 105-24, Pasadena, CA 91125, USA
16 CENTRA-Centro M. de Astrofisica and Department of Physics, IST, Lisbon, Portugal
17 LBNL, 1 Cyclotron Rd, Berkeley, CA 94720, USA
18 Anglo-Australian Observatory, PO Box 296, Epping, NSW 1710, Australia
19 Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa, Italy
Accepted: 24 June 2010
Aims. We present photometric properties and distance measurements of 252high redshift Type Ia supernovae (0.15 < z < 1.1) discovered during the first three years of the Supernova Legacy Survey (SNLS). These events were detected and their multi-colour 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 redshifts.
Methods. Systematic uncertainties arising from light curve modeling are studied, making use of two techniques to derive the peak magnitude, shape and colour of the supernovae, and taking advantage of a precise calibration of the SNLS fields.
Results. A flat ΛCDM cosmological fit to 231SNLS high redshift type Ia supernovae alone gives ΩM = 0.211 ± 0.034(stat) ± 0.069(sys). The dominant systematic uncertainty comes from uncertainties in the photometric calibration. Systematic uncertainties from light curve fitters come next with a total contribution of ± 0.026 on ΩM. No clear evidence is found for a possible evolution of the slope (β) of the colour-luminosity relation with redshift.
Key words: supernovae: general / cosmology: observations
Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l’Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. Based on observations obtained at the European Southern Observatory using the Very Large Telescope on the Cerro Paranal (ESO Large Programme 171.A-0486 & 176.A-0589). Based on observations (programs GS-2003B-Q-8, GN-2003B-Q-9, GS-2004A-Q-11, GN-2004A-Q-19, GS-2004B-Q-31, GN-2004B-Q-16, GS-2005A-Q-11, GN-2005A-Q-11, GS-2005B-Q-6, GN-2005B-Q-7, GN-2006A-Q-7, GN-2006B-Q-10) obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Particle Physics and Astronomy Research Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), CNPq (Brazil) and CONICET (Argentina). Based on observations obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation. Mark Sullivan acknowledges support from the Royal Society.
Table 9 is available in electronic form at http://aanda.org and at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (188.8.131.52) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/523/A7. Tables 10 and 11 are only available in electronic form at the CDS
© ESO, 2010