SNLS3: CONSTRAINTS ON DARK ENERGY COMBINING THE SUPERNOVA LEGACY SURVEY THREE-YEAR DATA WITH OTHER PROBES

Journal Article · Sat Aug 20 00:00:00 EDT 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/737/2/102· OSTI ID:21579912

Sullivan, M; Hook, I M ^[1]; Guy, J; Regnault, N; Astier, P; Balland, C; Hardin, D; Pain, R ^[2]; Conley, A; Carlberg, R G; Perrett, K M ^[3]; Basa, S ^[4]; Fouchez, D ^[5]; Howell, D A ^[6]; Palanque-Delabrouille, N; Rich, J; Ruhlmann-Kleider, V ^[7]; Pritchet, C J; Balam, D ^[8]; Baumont, S ^[9]

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1. Department of Physics (Astrophysics), University of Oxford, Keble Road, Oxford OX1 3RH (United Kingdom)
2. LPNHE, Universite Pierre et Marie Curie Paris 6, Universite Paris Diderot Paris 7, CNRS-IN2P3, 4 Place Jussieu, 75252 Paris Cedex 05 (France)
3. Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada)
4. LAM, CNRS, BP8, Pole de l'Etoile Site de Chateau-Gombert, 38 rue Frederic Joliot-Curie, 13388 Marseille Cedex 13 (France)
5. CPPM, Aix-Marseille Universite, CNRS/IN2P3, Marseille (France)
6. Las Cumbres Observatory Global Telescope Network, 6740 Cortona Dr., Suite 102, Goleta, CA 93117 (United States)
7. CEA, Centre de Saclay, Irfu/SPP, F-91191 Gif-sur-Yvette (France)
8. Department of Physics and Astronomy, University of Victoria, P.O. Box 3055 STN CSC, Victoria, BC V8T 1M8 (Canada)
9. LPSC, UJF, CNRS/IN2P3, INPG, 53 rue des Martyrs, 38026 Grenoble Cedex (France)

We present observational constraints on the nature of dark energy using the Supernova Legacy Survey three-year sample (SNLS3) of Guy et al. and Conley et al. We use the 472 Type Ia supernovae (SNe Ia) in this sample, accounting for recently discovered correlations between SN Ia luminosity and host galaxy properties, and include the effects of all identified systematic uncertainties directly in the cosmological fits. Combining the SNLS3 data with the full WMAP7 power spectrum, the Sloan Digital Sky Survey luminous red galaxy power spectrum, and a prior on the Hubble constant H{sub 0} from SHOES, in a flat universe we find {Omega}{sub m} = 0.269 {+-} 0.015 and w = -1.061{sup +0.069}{sub -} 0{sub .068} (where the uncertainties include all statistical and SN Ia systematic errors)-a 6.5% measure of the dark energy equation-of-state parameter w. The statistical and systematic uncertainties are approximately equal, with the systematic uncertainties dominated by the photometric calibration of the SN Ia fluxes-without these calibration effects, systematics contribute only a {approx}2% error in w. When relaxing the assumption of flatness, we find {Omega}{sub m} = 0.271 {+-} 0.015, {Omega}{sub k} = -0.002 {+-} 0.006, and w = -1.069{sup +0.091}{sub -0.092}. Parameterizing the time evolution of w as w(a) = w{sub 0} + w{sub a} (1 - a) gives w{sub 0} = -0.905 {+-} 0.196, w{sub a} = -0.984{sup +1.094}{sub -1.097} in a flat universe. All of our results are consistent with a flat, w = -1 universe. The size of the SNLS3 sample allows various tests to be performed with the SNe segregated according to their light curve and host galaxy properties. We find that the cosmological constraints derived from these different subsamples are consistent. There is evidence that the coefficient, {beta}, relating SN Ia luminosity and color, varies with host parameters at >4{sigma} significance (in addition to the known SN luminosity-host relation); however, this has only a small effect on the cosmological results and is currently a subdominant systematic.

• OSTI ID: 21579912
• Journal Information: Astrophysical Journal, Vol. 737, Issue 2; Other Information: DOI: 10.1088/0004-637X/737/2/102; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
COSMOLOGY
GALAXIES
LUMINOSITY
NONLUMINOUS MATTER
SUPERNOVAE
BINARY STARS
ERUPTIVE VARIABLE STARS
MATTER
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
STARS
VARIABLE STARS