D
D. A. Howell
Researcher at University of California, Santa Barbara
Publications - 59
Citations - 8093
D. A. Howell is an academic researcher from University of California, Santa Barbara. The author has contributed to research in topics: Supernova & Supernova Legacy Survey. The author has an hindex of 40, co-authored 59 publications receiving 7519 citations. Previous affiliations of D. A. Howell include Las Cumbres Observatory Global Telescope Network & University of Toronto.
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Journal ArticleDOI
SPECTRA AND HUBBLE SPACE TELESCOPE LIGHT CURVES OF SIX TYPE Ia SUPERNOVAE AT 0.511 <z< 1.12 AND THE UNION2 COMPILATION ∗
Rahman Amanullah,Chris Lidman,David Rubin,David Rubin,Greg Aldering,Pierre Astier,Kyle Barbary,Kyle Barbary,M. S. Burns,A. Conley,Kyle S. Dawson,S. E. Deustua,Mamoru Doi,Sebastien Fabbro,L. Faccioli,L. Faccioli,H. K. Fakhouri,H. K. Fakhouri,Gastón Folatelli,A. S. Fruchter,Hisanori Furusawa,G. Garavini,G. Goldhaber,G. Goldhaber,Ariel Goobar,Donald E. Groom,I. M. Hook,I. M. Hook,D. A. Howell,D. A. Howell,Nobunari Kashikawa,A. G. Kim,R. A. Knop,M. Kowalski,Eric V. Linder,J. Meyers,J. Meyers,Tomoki Morokuma,S. Nobili,J. Nordin,Peter Nugent,Linda Ostman,Reynald Pain,Nino Panagia,Nino Panagia,Saul Perlmutter,Saul Perlmutter,J. Raux,Pilar Ruiz-Lapuente,A. L. Spadafora,M. Strovink,M. Strovink,Nao Suzuki,Lifan Wang,W. M. Wood-Vasey,Naoki Yasuda +55 more
TL;DR: Kowalski et al. as mentioned in this paper reported on work to increase the number of well-measured Type Ia supernovae (SNe Ia) at high redshifts.
Journal ArticleDOI
Supernova constraints and systematic uncertainties from the first three years of the supernova legacy survey
Alex Conley,Alex Conley,Julien Guy,Mark Sullivan,Nicolas Regnault,Pierre Astier,Christophe Balland,Christophe Balland,Stéphane Basa,Raymond G. Carlberg,Dominique Fouchez,D. Hardin,I. M. Hook,I. M. Hook,D. A. Howell,D. A. Howell,Reynald Pain,Nathalie Palanque-Delabrouille,Kathy Perrett,Kathy Perrett,C. J. Pritchet,Jeffrey A. Rich,V. Ruhlmann-Kleider,David D. Balam,S. Baumont,Richard S. Ellis,Richard S. Ellis,Sebastien Fabbro,Sebastien Fabbro,H. K. Fakhouri,N. Fourmanoit,Santiago González-Gaitán,Melissa L. Graham,Michael J. Hudson,Eric Hsiao,T. Kronborg,C. Lidman,A. Mourao,James D. Neill,Saul Perlmutter,Saul Perlmutter,P. Ripoche,P. Ripoche,Nao Suzuki,E. S. Walker +44 more
TL;DR: In this article, the authors 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 high-quality joint sample of 472 SNe (123 low-$z, 93 SDSS, 242 SNLS, and 14 {\it Hubble Space Telescope}).
Journal ArticleDOI
The Supernova Legacy Survey 3-year sample: Type Ia supernovae photometric distances and cosmological constraints ,
Julien Guy,Mark Sullivan,Alex Conley,Alex Conley,Nicolas Regnault,Pierre Astier,Christophe Balland,Christophe Balland,Stéphane Basa,Raymond G. Carlberg,Dominique Fouchez,D. Hardin,I. M. Hook,I. M. Hook,D. A. Howell,D. A. Howell,Reynald Pain,Nathalie Palanque-Delabrouille,Kathy Perrett,Kathy Perrett,Christopher J. Pritchet,J. Rich,V. Ruhlmann-Kleider,David D. Balam,S. Baumont,Rowan Ellis,Rowan Ellis,Sebastien Fabbro,Sebastien Fabbro,H. K. Fakhouri,N. Fourmanoit,Santiago González-Gaitán,Melissa L. Graham,Eric Hsiao,T. Kronborg,C. Lidman,A. Mourao,Saul Perlmutter,P. Ripoche,P. Ripoche,Nao Suzuki,Emma S. Walker +41 more
TL;DR: In this paper, photometric properties and distance measurements of 252 high redshift Type Ia supernovae (0.15 < z < 1.1) were presented and their multi-colour light curves measured using the MegaPrime/MegaCam instrument at the Canada-France-Hawaii Telescope (CFHT).
Journal ArticleDOI
SNLS3: Constraints on dark energy combining the supernova legacy survey three-year data with other probes
Mark Sullivan,Julien Guy,Alex Conley,Alex Conley,Nicolas Regnault,Pierre Astier,Christophe Balland,Christophe Balland,Stéphane Basa,Raymond G. Carlberg,Dominique Fouchez,D. Hardin,I. M. Hook,I. M. Hook,D. A. Howell,D. A. Howell,Reynald Pain,N. Palanque-Delabrouille,Kathy Perrett,Kathy Perrett,C. J. Pritchet,Jeffrey A. Rich,V. Ruhlmann-Kleider,David D. Balam,S. Baumont,Richard S. Ellis,Richard S. Ellis,Sebastien Fabbro,H. K. Fakhouri,N. Fourmanoit,Santiago González-Gaitán,Melissa L. Graham,Melissa L. Graham,Michael J. Hudson,Michael J. Hudson,Eric Hsiao,T. Kronborg,C. Lidman,A. Mourao,James D. Neill,Saul Perlmutter,Saul Perlmutter,P. Ripoche,P. Ripoche,Nao Suzuki,E. S. Walker +45 more
TL;DR: In this article, the authors 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., and they find that the cosmological constraints derived from these different subsamples are consistent.
Journal ArticleDOI
The dependence of Type Ia Supernovae luminosities on their host galaxies
Mark Sullivan,A. Conley,D. A. Howell,D. A. Howell,James D. Neill,Pierre Astier,Christophe Balland,S. Basa,Raymond G. Carlberg,Dominique Fouchez,Julien Guy,D. Hardin,I. M. Hook,I. M. Hook,Reynald Pain,Nathalie Palanque-Delabrouille,Kathy Perrett,Kathy Perrett,C. J. Pritchet,Nicolas Regnault,J. Rich,V. Ruhlmann-Kleider,S. Baumont,S. Baumont,Eric Hsiao,T. Kronborg,C. Lidman,Saul Perlmutter,Saul Perlmutter,E. S. Walker +29 more
TL;DR: In this paper, the authors used the Supernova Legacy Survey (SNLS) and other data to show that there is an additional dependence on the global characteristics of their host galaxies: events of the same light-curve shape and colour are, on average, 0.08mag (~4.0sigma) brighter in massive host galaxies (presumably metal-rich) and galaxies with low specific star-formation rates (sSFR).