Nicolas Regnault

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We present a new compilation of Type Ia supernovae (SNe Ia), a new dataset of low-redshift nearby-Hubble-flow SNe and new analysis procedures to work with these heterogeneous compilations. This " Union " compilation of 414 SN Ia, which reduces to 307 SNe after selection cuts, includes the recent large samples of SNe Ia from the Supernova Legacy Survey and(More)
We report measurements of M , Ã , and w from 11 supernovae (SNe) at z ¼ 0:36 0:86 with high-quality light curves measured using WFPC2 on the Hubble Space Telescope (HST). This is an independent set of high-redshift SNe that confirms previous SN evidence for an accelerating universe. The high-quality light curves available from photometry on WFPC2 make it(More)
Aims. We present an empirical model of Type Ia supernovae spectro-photometric evolution with time. Methods. The model is built using a large data set including light-curves and spectra of both nearby and distant supernovae, the latter being observed by the SNLS collaboration. We derive the average spectral sequence of Type Ia supernovae and their main(More)
The 5-year project Supernova Legacy Survey (SNLS) delivers ∼ 100 Type-Ia supernovae (SNe Ia) per year, in the redshift range 0.3 < z < 1.0, with well-sampled g ′ r ′ i ′ z ′ lightcurves. The SNLS Collaboration uses the 1 deg 2 Megacam imager (36 2048×4612 thinned CCDs) mounted on the 3.6-m Canada-France-Hawaii Telescope (CFHT) to observe four fields around(More)
Aims. 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 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),(More)
We present the first high-redshift Hubble diagram for Type II-P supernovae (SNe II-P) based upon five events at redshift up to z ∼ 0.3. This diagram was constructed using photometry from the Canada-France-Hawaii Telescope Super-nova Legacy Survey and absorption line spectroscopy from the Keck observatory. The method used to measure distances to these(More)
Accepted —. Received —; in original form —. ABSTRACT 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 earlier evidence for a cosmological constant by explicitly comparing SNe residing in galaxies likely to contain negligible dust with the(More)
Massive stars undergo a violent death when the supply of nuclear fuel in their cores is exhausted, resulting in a catastrophic "core-collapse" supernova. Such events are usually only detected at least a few days after the star has exploded. Observations of the supernova SNLS-04D2dc with the Galaxy Evolution Explorer space telescope reveal a radiative(More)