Publications (80)
The effect of progenitor age and metallicity on luminosity and 56Ni yield in Type Ia supernovae
D. A. Howell, M. Sullivan, E. F. Brown +23
Timmes, Brown & Truran found that metallicity variations could theoretically account for a 25% variation in the mass of 56Ni synthesized in Type Ia supernovae (SNe Ia), and thus ac…
The Type Ia Supernova Rate in Radio and Infrared Galaxies from the CFHT Supernova Legacy Survey
M. L. Graham, C. J. Pritchet, M. Sullivan +25
We have combined the large SN Ia database of the Canada-France-Hawaii Telescope Supernova Legacy Survey and catalogs of galaxies with photometric redshifts, VLA 1.4 GHz radio sourc…
Photometric redshifts for supernovae Ia in the Supernova Legacy Survey
N. Palanque-Delabrouille, V. Ruhlmann-Kleider, S. Pascal +17
We present a method using the SALT2 light curve fitter to determine the redshift of Type Ia supernovae in the Supernova Legacy Survey (SNLS) based on their photometry in g', r', i'…
Bose-Einstein Correlations in Charged Current Muon-Neutrino Interactions in the NOMAD Experiment at CERN
NOMAD Collaboration, P. Astier
Bose-Einstein Correlations in one and two dimensions have been studied, with high statistics, in charged current muon-neutrino interaction events collected with the NOMAD detector…
PHotometry Assisted Spectral Extraction (PHASE) and identification of SNLS supernovae
S. Baumont, C. Balland, P. Astier +7
Aim: We present new extraction and identification techniques for supernova (SN) spectra developed within the Supernova Legacy Survey (SNLS) collaboration. Method: The new spectral…
Timescale Stretch Parameterization of Type Ia Supernova B-band Light Curves
G. Goldhaber, D. E. Groom, A. Kim +24
R-band intensity measurements along the light curve of Type Ia supernovae discovered by the Supernova Cosmology Project (SCP) are fitted in brightness to templates allowing a free…
The Supernova Legacy Survey 3-year sample: Type Ia Supernovae photometric distances and cosmological constraints
J. Guy, M. Sullivan, A. Conley +31
We present photometric properties and distance measurements of 252 high redshift Type Ia supernovae (0.15 < z < 1.1) discovered during the first three years of the Supernova Legacy…
PlatoSim: An end-to-end PLATO camera simulator for modelling high-precision space-based photometry
N. Jannsen, J. De Ridder, D. Seynaeve +21
PLAnetary Transits and Oscillations of stars (PLATO) is the ESA M3 space mission dedicated to detect and characterise transiting exoplanets including information from the asterosei…
SNLS Spectroscopy: Testing for Evolution in Type Ia Supernovae
T. J. Bronder, I. M. Hook, P. Astier +19
Aims: We present a quantitative study of a new data set of high redshift Type Ia supernovae spectra, observed at the Gemini telescopes during the first 34 months of the Supernova L…
Supernova Legacy Survey: Using Spectral Signatures To Improve Type Ia Supernovae As Distance Indicators
E. S. Walker, I. M. Hook, M. Sullivan +22
GMOS optical long-slit spectroscopy at the Gemini-North telescope was used to classify targets from the Supernova Legacy Survey (SNLS) from July 2005 and May 2006 - May 2008. Durin…
The distant Type Ia supernova rate
R. Pain, S. Fabbro, M. Sullivan +26
We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample, which su…
Spectroscopic confirmation of high-redshift supernovae with the ESO VLT
C. Lidman, D. A. Howell, G. Folatelli +44
We present VLT FORS1 and FORS2 spectra of 39 candidate high-redshift supernovae that were discovered as part of a cosmological study using Type Ia supernovae (SNe Ia) over a wide r…
The brighter-fatter effect and pixel correlations in CCD sensors
P. Antilogus, P. Astier, P. Doherty +2
We present evidence that spots imaged using astronomical CCDs do not exactly scale with flux: bright spots tend to be broader than faint ones, using the same illumination pattern.…
The Dependence of Type Ia Supernova Luminosities on their Host Galaxies
M. Sullivan, A. Conley, D. A. Howell +22
(Abridged) Precision cosmology with Type Ia supernovae (SNe Ia) makes use of the fact that SN Ia luminosities depend on their light-curve shapes and colours. Using Supernova Legacy…
The Supernova Legacy Survey: Measurement of Omega_M, Omega_Lambda and w from the First Year Data Set
P. Astier, J. Guy, N. Regnault +39
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 an…
Peculiar velocity cosmology with type Ia supernovae
R. Graziani, M. Rigault, N. Regnault +20
Type Ia Supernovae have yet again the opportunity to revolutionize the field of cosmology as the new generation of surveys are acquiring thousands of nearby SNeIa opening a new era…
Improving the astrometric solution of the Hyper Suprime-Cam with anisotropic Gaussian processes
P. -F. Léget, P. Astier, N. Regnault +5
We study astrometric residuals from a simultaneous fit of Hyper Suprime-Cam images. We aim to characterize these residuals and study the extent to which they are dominated by atmos…
Spectra and Light Curves of Six Type Ia Supernovae at 0.511 < z < 1.12 and the Union2 Compilation
R. Amanullah, C. Lidman, D. Rubin +42
We report on work to increase the number of well-measured Type Ia supernovae (SNe Ia) at high redshifts. Light curves, including high signal-to-noise HST data, and spectra of six S…
Supernovae and the Nature of the Dark Energy
M. Goliath, R. Amanullah, P. Astier +2
The use of Type Ia supernovae as calibrated standard candles is one of the most powerful tools to study the expansion history of the universe and thereby its energy components. Whi…
Clustering of supernova Ia host galaxies
R. G. Carlberg, M. Sullivan, D. Le Borgne +16
For the first time the cross-correlation between type Ia supernova host galaxies and surrounding field galaxies is measured using the Supernova Legacy Survey sample. Over the z=0.2…
Supernova Constraints and Systematic Uncertainties from the First 3 Years of the Supernova Legacy Survey
A. Conley, J. Guy, M. Sullivan +33
We combine high redshift Type Ia supernovae from the first 3 years of the Supernova Legacy Survey (SNLS) with other supernova (SN) samples, primarily at lower redshifts, to form a…
The Carnegie Supernova Project: First Near-Infrared Hubble Diagram to z~0.7
Wendy L. Freedman, Christopher R. Burns, M. M. Phillips +37
The Carnegie Supernova Project (CSP) is designed to measure the luminosity distance for Type Ia supernovae (SNe Ia) as a function of redshift, and to set observational constraints…
Rates and properties of type Ia supernovae as a function of mass and star-formation in their host galaxies
M. Sullivan, D. Le Borgne, C. J. Pritchet +27
(ABRIDGED) We show that Type Ia supernovae (SNe Ia) are formed within both very young and old stellar populations, with observed rates that depend on the stellar mass and mean star…
New Constraints on , , and w from an Independent Set of Eleven High-Redshift Supernovae Observed with HST
R. A. Knop, G. Aldering, R. Amanullah +45
We report measurements of , , and w from eleven supernovae at z=0.36-0.86 with high-quality lightcurves measured using WFPC-2 on the HST. This is an independent set of…
Inclusive production of and mesons in charged current interactions
NOMAD Collaboration, P. Astier
The inclusive production of the meson resonances , and in neutrino-nucleus charged current interactions has been studied with the NOMAD detector…
Final NOMAD results on nu_mu->nu_tau and nu_e->nu_tau oscillations including a new search for nu_tau appearance using hadronic tau decays
NOMAD Collaboration, P. Astier
Results from the nu_tau appearance search in a neutrino beam using the full NOMAD data sample are reported. A new analysis unifies all the hadronic tau decays, significantly improv…
SALT: a Spectral Adaptive Light curve Template for Type Ia Supernovae
J. Guy, P. Astier, S. Nobili +2
We present a new method to parameterize Type Ia Supernovae (SN Ia) multi-color light curves. The method was developed in order to analyze the large number of SN Ia multi-color ligh…
A study of backward going and in interactions with the NOMAD detector
The NOMAD Collaboration, P. Astier
Backward proton and production has been studied in interactions with carbon nuclei. Detailed analyses of the momentum distributions, of the production rates, and o…
Prediction of Neutrino Fluxes in the NOMAD Experiment
NOMAD Collaboration, P. Astier
The method developed for the calculation of the flux and composition of the West Area Neutrino Beam used by NOMAD in its search for neutrino oscillations is described. The calculat…
Evolution in the Volumetric Type Ia Supernova Rate from the Supernova Legacy Survey
K. Perrett, M. Sullivan, A. Conley +23
We present a measurement of the volumetric Type Ia supernova (SN Ia) rate (SNR_Ia) as a function of redshift for the first four years of data from the Canada-France-Hawaii Telescop…
The Rise Time of Type Ia Supernovae from the Supernova Legacy Survey
A. Conley, D. A. Howell, A. Howes +24
We compare the rise times of nearby and distant Type Ia supernovae (SNe Ia) as a test for evolution using 73 high-redshift spectroscopically-confirmed SNe Ia from the first two yea…
Type Ia Supernovae Rates and Galaxy Clustering from the CFHT Supernova Legacy Survey
M. L. Graham, C. J. Pritchet, M. Sullivan +25
The Canada-France-Hawaii Telescope Supernova Legacy Survey (SNLS) has created a large homogeneous database of intermediate redshift (0.2 < z < 1.0) type Ia supernovae (SNe Ia). The…
Quantitative comparison between Type Ia supernova spectra at low and high redshifts: A case study
G. Garavini, G. Folatelli, S. Nobili +44
We develop a method to measure the strength of the absorption features in Type Ia supernova (SN Ia) spectra and use it to make a quantitative comparison between the spectra of Type…
Real-time Analysis and Selection Biases in the Supernova Legacy Survey
K. Perrett, D. Balam, M. Sullivan +13
The Supernova Legacy Survey (SNLS) has produced a high-quality, homogeneous sample of Type Ia supernovae (SNe Ia) out to redshifts greater than z=1. In its first four years of full…
SNLS3: Constraints on Dark Energy Combining the Supernova Legacy Survey Three Year Data with Other Probes
M. Sullivan, J. Guy, A. Conley +33
We present observational constraints on the nature of dark energy using the Supernova Legacy Survey three year sample (SNLS3) of Guy et al. (2010) and Conley et al. (2011). We use…
Light curves of five type Ia supernovae at intermediate redshift
R. Amanullah, V. Stanishev, A. Goobar +14
We present multi-band light curves and distances for five type Ia supernovae at intermediate redshifts, 0.18<z<0.27. Three telescopes on the Canary Island of La Palma, INT, NOT and…
Restframe I-band Hubble diagram for type Ia supernovae up to redshift z ~0.5
The Supernova Cosmology Project, :, S. Nobili +35
We present a novel technique for fitting restframe I-band light curves on a data set of 42 Type Ia supernovae (SNe Ia). Using the result of the fit, we construct a Hubble diagram w…
Two superluminous supernovae from the early universe discovered by the Supernova Legacy Survey
D. A. Howell, D. Kasen, C. Lidman +14
We present spectra and lightcurves of SNLS 06D4eu and SNLS 07D2bv, two hydrogen-free superluminous supernovae discovered by the Supernova Legacy Survey. At z = 1.588, SNLS 06D4eu i…
Constraining Type Ia Supernovae progenitors from three years of SNLS data
F. B. Bianco, D. A. Howell, M. Sullivan +20
While it is generally accepted that Type Ia supernovae are the result of the explosion of a carbon-oxygen White Dwarf accreting mass in a binary system, the details of their genesi…
Gravitational lensing in the Supernova Legacy Survey (SNLS)
T. Kronborg, D. Hardin, J. Guy +18
The observed brightness of Type Ia supernovae is affected by gravitational lensing caused by the mass distribution along the line of sight, which introduces an additional dispersio…
Spectroscopic Observations and Analysis of the Unusual Type Ia SN 1999ac
The Supernova Cosmology Project, :, G. Garavini +55
We present optical spectra of the peculiar Type Ia supernova (SN Ia) 1999ac. The data extend from -15 to +42 days with respect to B-band maximum and reveal an event that is unusual…
Dark energy constraints and correlations with systematics from CFHTLS weak lensing, SNLS supernovae Ia and WMAP5
M. Kilbinger, K. Benabed, J. Guy +15
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 cosmo…
Constraining the CDM and Galileon models with recent cosmological data
J. Neveu, V. Ruhlmann-Kleider, P. Astier +4
The Galileon theory belongs to the class of modified gravity models that can explain the late-time accelerated expansion of the Universe. In previous works, cosmological constraint…
Evidence for self-interaction of charge distribution in charge-coupled devices
A. Guyonnet, P. Astier, P. Antilogus +2
Charge-coupled devices (CCDs) are widely used in astronomy to carry out a variety of measurements, such as for flux or shape of astrophysical objects. The data reduction procedures…
Search for heavy neutrinos mixing with tau neutrinos
NOMAD Collaboration, P. Astier
We report on a search for heavy neutrinos ($\nus$) produced in the decay $D_s\to Ï\nus$ at the SPS proton target followed by the decay $\nudecay$ in the NOMAD detector. Both decay…
SiFTO: An Empirical Method for Fitting SNe Ia Light Curves
A. Conley, M. Sullivan, E. Y. Hsiao +14
We present SiFTO, a new empirical method for modeling type Ia supernovae (SNe Ia) light curves by manipulating a spectral template. We make use of high-redshift SN observations whe…
Spectroscopy of twelve Type Ia supernovae at intermediate redshift
C. Balland, M. Mouchet, R. Pain +15
We present spectra of twelve Type Ia supernovae obtained in 1999 at the William Herschel Telescope and the Nordic Optical Telescope during a search for Type Ia supernovae (SN Ia) a…
Subluminous Type Ia Supernovae at High Redshift from the Supernova Legacy Survey
S. Gonzalez-Gaitan, K. Perrett, M. Sullivan +15
The rate evolution of subluminous Type Ia Supernovae is presented using data from the Supernova Legacy Survey. This sub-sample represents the faint and rapidly-declining light-curv…
Spectroscopic observations of eight supernovae at intermediate redshift
C. Balland, M. Mouchet, R. Amanullah +16
We present spectra of six Type Ia and two Type II supernovae obtained in June 2002 at the William Herschel Telescope during a search for Type Ia supernovae (SNIa) at intermediate r…
The DICE calibration project: design, characterization, and first results
N. Regnault, A. Guyonnet, K. Schahmanèche +12
We describe the design, operation, and first results of a photometric calibration project, called DICE (Direct Illumination Calibration Experiment), aiming at achieving precise ins…
The Rise-Time of Normal and Subluminous Type Ia Supernovae
S. Gonzalez-Gaitan, A. Conley, F. B. Bianco +21
We calculate the average stretch-corrected rise-time of type Ia supernovae (SNe Ia) in the Supernova Legacy Survey. We use the aggregate lightcurves of spectroscopic and photometri…
Supernova / Acceleration Probe: A Satellite Experiment to Study the Nature of the Dark Energy
SNAP Collaboration, G. Aldering, W. Althouse +109
The Supernova / Acceleration Probe (SNAP) is a proposed space-based experiment designed to study the dark energy and alternative explanations of the acceleration of the Universe's…
Verifying the Cosmological Utility of Type Ia Supernovae: Implications of a Dispersion in the Ultraviolet Spectra
R. S. Ellis, M. Sullivan, P. E. Nugent +16
We analyze the mean rest-frame ultraviolet (UV) spectrum of Type Ia Supernovae (SNe Ia) and its dispersion using high signal-to-noise Keck-I/LRIS-B spectroscopy for a sample of 36…
The ESO/VLT 3rd year Type Ia supernova data set from the Supernova Legacy Survey
C. Balland, S. Baumont, S. Basa +24
We present 139 spectra of 124 Type Ia supernovae (SNeIa) that were observed at the ESO/VLT during the first three years of the Canada-France-Hawai Telescope (CFHT) Supernova Legacy…
An Efficient Approach to Obtaining Large Numbers of Distant Supernova Host Galaxy Redshifts
C. Lidman, V. Ruhlmann-Kleider, M. Sullivan +20
We use the wide-field capabilities of the 2dF fibre positioner and the AAOmega spectrograph on the Anglo-Australian Telescope (AAT) to obtain redshifts of galaxies that hosted supe…
Photometric selection of Type Ia supernovae in the Supernova Legacy Survey
G. Bazin, V. Ruhlmann-Kleider, N. Palanque-Delabrouille +23
We present a sample of 485 photometrically identified Type Ia supernova candidates mined from the first three years of data of the CFHT SuperNova Legacy Survey (SNLS). The images w…
Cosmological Parameter Uncertainties from SALT-II Type Ia Supernova Light Curve Models
J. Mosher, J. Guy, R. Kessler +11
We use simulated SN Ia samples, including both photometry and spectra, to perform the first direct validation of cosmology analysis using the SALT-II light curve model. This valida…
Photometric selection of high-redshift type Ia supernovae
M. Sullivan, D. A. Howell, K. Perrett +26
We present a method for selecting high-redshift type Ia supernovae (SNe Ia) located via rolling SN searches. The technique, using both color and magnitude information of events fro…
Spectroscopic Observations and Analysis of the Peculiar SN 1999aa
G. Garavini, G. Folatelli, A. Goobar +55
We present an extensive new time-series of spectroscopic data of the peculiar SN 1999aa in NGC 2595. Our data set includes 25 optical spectra between -11 and +58 days with respect…
SALT2: using distant supernovae to improve the use of Type Ia supernovae as distance indicators
J. Guy, P. Astier, S. Baumont +22
We present an empirical model of Type Ia supernovae spectro-photometric evolution with time. The model is built using a large data set including light-curves and spectra of both ne…
The Core-collapse rate from the Supernova Legacy Survey
G. Bazin, N. Palanque-Delabrouille, J. Rich +27
We use three years of data from the Supernova Legacy Survey (SNLS) to study the general properties of core-collapse and type Ia supernovae. This is the first such study using the "…
Experimental constraints on the uncoupled Galileon model from SNLS3 data and other cosmological probes
J. Neveu, V. Ruhlmann-Kleider, A. Conley +4
The Galileon model is a modified gravity theory that may provide an explanation for the accelerated expansion of the Universe. This model does not suffer from instabilities or ghos…
First experimental constraints on the disformally coupled Galileon model
J. Neveu, V. Ruhlmann-Kleider, P. Astier +6
The Galileon model is a modified gravity model that can explain the late-time accelerated expansion of the Universe. In a previous work, we derived experimental constraints on the…
The Hubble Diagram of Type Ia Supernovae as a Function of Host Galaxy Morphology
M. Sullivan, R. S. Ellis, G. Aldering +41
(Abridged) We present new results on the Hubble diagram of distant type Ia supernovae (SNe Ia) segregated according to the type of host galaxy. This makes it possible to check earl…
Improved Photometric Calibration of the SNLS and the SDSS Supernova Surveys
M. Betoule, J. Marriner, N. Regnault +13
We present a combined photometric calibration of the SNLS and the SDSS supernova survey, which results from a joint effort of the SDSS and the SNLS collaborations. We deliver fluxe…
The Nearby Supernova Factory
W. M. Wood-Vasey, G. Aldering, B. C. Lee +19
The Nearby Supernova Factory (SNfactory) is an ambitious project to find and study in detail approximately 300 nearby Type Ia supernovae (SNe~Ia) at redshifts 0.03<z<0.08. This pro…
Extending the supernova Hubble diagram to z~1.5 with the Euclid space mission
P. Astier, C. Balland, M. Brescia +25
We forecast dark energy constraints that could be obtained from a new large sample of Type Ia supernovae where those at high redshift are acquired with the Euclid space mission. We…
Photometry of supernovae in an image series : methods and application to the Supernova Legacy Survey (SNLS)
P. Astier, P. El Hage, J. Guy +6
We present a technique to measure lightcurves of time-variable point sources on a spatially structured background from imaging data. The technique was developed to measure light cu…
Measurement of the Antilambda Polarization in nu_mu Charged Current Interactions in the NOMAD Experiment
The NOMAD Collaboration, P. Astier
We present a measurement of the polarization of Antilambda hyperons produced in nu_mu charged current interactions. The full data sample from the NOMAD experiment has been analyzed…
Gemini Spectroscopy of Supernovae from SNLS: Improving High Redshift SN Selection and Classification
D. A. Howell, M. Sullivan, K. Perrett +22
We present new techiques for improving the efficiency of supernova (SN) classification at high redshift using 64 candidates observed at Gemini North and South during the first year…
DUNE: The Dark Universe Explorer
A. Refregier, O. Boulade, Y. Mellier +22
Understanding the nature of Dark Matter and Dark Energy is one of the most pressing issues in cosmology and fundamental physics. The purpose of the DUNE (Dark UNiverse Explorer) mi…
The Drift Chambers Of The Nomad Experiment
M. Anfreville, P. Astier, M. Authier +30
We present a detailed description of the drift chambers used as an active target and a tracking device in the NOMAD experiment at CERN. The main characteristics of these chambers a…
Euclid Definition Study Report
R. Laureijs, J. Amiaux, S. Arduini +216
Euclid is a space-based survey mission from the European Space Agency designed to understand the origin of the Universe's accelerating expansion. It will use cosmological probes to…
Photometric Calibration of the Supernova Legacy Survey Fields
N. Regnault, A. Conley, J. Guy +13
We present the photometric calibration of the Supernova Legacy Survey (SNLS) fields. The SNLS aims at measuring the distances to SNe Ia at (0.3<z<1) using MegaCam, the 1 deg^2 imag…
Search for nu(mu)-->nu(e) Oscillations in the NOMAD Experiment
NOMAD Collaboration, P. Astier
We present the results of a search for nu(mu)-->nu(e) oscillations in the NOMAD experiment at CERN. The experiment looked for the appearance of nu(e) in a predominantly nu(mu) wide…
The ESO's VLT Type Ia supernova spectral set of the final two years of SNLS
C. Balland, F. Cellier-Holzem, C. Lidman +24
We aim to present 70 spectra of 68 new high-redshift type Ia supernovae (SNeIa) measured at ESO's VLT during the final two years of operation (2006-2008) of the Supernova Legacy Su…
Improved cosmological constraints from a joint analysis of the SDSS-II and SNLS supernova samples
M. Betoule, R. Kessler, J. Guy +60
We present cosmological constraints from a joint analysis of type Ia supernova (SN Ia) observations obtained by the SDSS-II and SNLS collaborations. The data set includes several l…
The Type Ia Supernova Rate at z ~0.5 from the Supernova Legacy Survey
J. D. Neill, M. Sullivan, D. Balam +33
We present a measurement of the distant Type Ia supernova rate derived from the first two years of the Canada -- France -- Hawaii Telescope Supernova Legacy Survey. We observed fou…
Dark energy constraints from a space-based supernova survey
P. Astier, J. Guy, R. Pain +1
We present a forecast of dark energy constraints that could be obtained from a large sample of distances to Type Ia supernovae detected and measured from space. We simulate the sup…
The Supernova Type Ia Rate Evolution with SNLS
J. D. Neill, M. Sullivan, D. Balam +36
We present a progress report on a project to derive the evolution of the volumetric supernova Type Ia rate from the Supernova Legacy Survey. Our preliminary estimate of the rate ev…