Issue |
A&A
Volume 447, Number 1, February III 2006
|
|
---|---|---|
Page(s) | 31 - 48 | |
Section | Cosmology (including clusters of galaxies) | |
DOI | https://doi.org/10.1051/0004-6361:20054185 | |
Published online | 27 January 2006 |
The Supernova Legacy Survey: measurement of
,
and w from
the first year data set
1
LPNHE, CNRS-IN2P3 and Universités Paris VI & VII, 4 place Jussieu, 75252 Paris Cedex 05, France; e-mail: astier@in2p3.fr
2
APC, Collège de France, 11 place Marcellin Berthelot, 75005 Paris, France
3
DSM/DAPNIA, CEA/Saclay, 91191 Gif-sur-Yvette Cedex, France
4
Department of Physics and Astronomy, University of Victoria, PO Box 3055, Victoria, BC VSW 3P6, Canada
5
LAM, CNRS, BP8, Traverse du Siphon, 13376 Marseille Cedex 12, France
6
Department of Astronomy and Astrophysics, University of Toronto, 60 St. George Street, Toronto, ON M5S 3H8, Canada
7
CENTRA-Centro M. de Astrofisica and Department of Physics, IST, Lisbon, Portugal
8
CPPM, CNRS-IN2P3 and Université Aix-Marseille II, Case 907, 13288 Marseille Cedex 9, France
9
University of Oxford Astrophysics, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, UK
10
Université de Savoie, 73000 Chambery, France
11
LBNL, 1 Cyclotron Rd, Berkeley, CA 94720, USA
12
ESO, Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago 19, Chile
13
CRAL, 9 avenue Charles André, 69561 Saint-Genis-Laval cedex, France
14
California Institute of Technology, Pasadena, California, USA
15
LUTH, UMR 8102, CNRS and Observatoire de Paris, 92195 Meudon, France
16
Department of Physics, Stockholm University, Sweden
17
IoA, University of Cambridge, Madingley Road, Cambridge CB3 0EZ, UK
18
Department of Physics, University of California Berkeley, Berkeley, CA 94720, USA
Received:
9
September
2005
Accepted:
11
October
2005
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, as part of the CFHT Legacy Survey (CFHTLS). 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 , 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:
for a flat ΛCDM model; and
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.
Key words: supernovae: general / cosmology: observations / cosmological parameters
© ESO, 2006
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.