S. Perlmutter
A5030135192- Gamma-ray bursts and supernovae
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Astrophysics and Cosmic Phenomena
- Galaxies: Formation, Evolution, Phenomena
- Pulsars and Gravitational Waves Research
- Astronomical Observations and Instrumentation
- Astrophysical Phenomena and Observations
- Cosmology and Gravitation Theories
- CCD and CMOS Imaging Sensors
- Astro and Planetary Science
- Adaptive optics and wavefront sensing
- Neutrino Physics Research
- Geophysics and Gravity Measurements
- Calibration and Measurement Techniques
- Dark Matter and Cosmic Phenomena
- Nuclear Physics and Applications
- Radio Astronomy Observations and Technology
- Space Science and Extraterrestrial Life
- Planetary Science and Exploration
- Solar and Space Plasma Dynamics
- Scientific Research and Discoveries
- Infrared Target Detection Methodologies
- Astrophysics and Star Formation Studies
- History and Developments in Astronomy
Lawrence Berkeley National Laboratory
2014-2024
University of California, Berkeley
2015-2024
K Lab (United States)
2017-2023
Thyssenkrupp (Slovakia)
2019
Fermi National Accelerator Laboratory
1995-2018
Centre National de la Recherche Scientifique
2007-2015
Institute of Nuclear Physics of Lyon
2015
Institut National de Physique Nucléaire et de Physique des Particules
2015
Université Claude Bernard Lyon 1
2015
Johns Hopkins University
2013
We report measurements of the mass density, ΩM, and cosmological-constant energy ΩΛ, universe based on analysis 42 type Ia supernovae discovered by Supernova Cosmology Project. The magnitude-redshift data for these supernovae, at redshifts between 0.18 0.83, are fitted jointly with a set from Calán/Tololo Survey, below 0.1, to yield values cosmological parameters. All supernova peak magnitudes standardized using SN light-curve width-luminosity relation. measurement yields joint probability...
We present distance measurements to 71 high redshift type Ia supernovae discovered during the first year of 5-year Supernova Legacy Survey (SNLS). These events were detected and their multi-color light-curves measured using MegaPrime/MegaCam instrument at Canada-France-Hawaii Telescope (CFHT), by repeatedly imaging four one-square degree fields in bands, as part CFHT (CFHTLS). Follow-up spectroscopy was performed VLT, Gemini Keck telescopes confirm nature measure redshift. With this data...
Aims. We present cosmological constraints from a joint analysis of type Ia supernova (SN Ia) observations obtained by the SDSS-II and SNLS collaborations. The dataset includes several low-redshift samples (z< 0.1), all three seasons (0.05 <z< 0.4), years (0.2 1), it totals 740 spectroscopically confirmed supernovae with high-quality light curves.
We present Advanced Camera for Surveys, NICMOS, and Keck adaptive-optics-assisted photometry of 20 Type Ia supernovae (SNe Ia) from the Hubble Space Telescope (HST) Cluster Supernova Survey. The SNe were discovered over redshift interval 0.623 < z 1.415. Of these Ia, 14 pass our strict selection cuts are used in combination with world's sample to derive best current constraints on dark energy. new 10 beyond = 1, thereby nearly doubling statistical weight HST-discovered this redshift. Our...
We report measurements of ΩM, ΩΛ, and w from 11 supernovae (SNe) at z = 0.36-0.86 with high-quality light curves measured using WFPC2 on the Hubble Space Telescope (HST). This is an independent set high-redshift SNe that confirms previous SN evidence for accelerating universe. The available photometry make it possible these alone to provide cosmological parameters comparable in statistical weight results. Combined earlier Supernova Cosmology Project data, new yield a measurement mass density...
We present a new compilation of Type Ia supernovae (SNe Ia), dataset low-redshift nearby-Hubble-flow SNe and analysis procedures to work with these heterogeneous compilations. This ``Union'' 414 SN Ia, which reduces 307 after selection cuts, includes the recent large samples from Supernova Legacy Survey ESSENCE Survey, older datasets, as well recently extended distant observed HST. A single, consistent blind procedure is used for all various subsamples, implemented that consistently weights...
We have developed a technique to systematically discover and study high-redshift supernovae that can be used measure the cosmological parameters. report here results based on initial seven of more than 28 discovered date in supernova search Supernova Cosmology Project. find an observational dispersion peak magnitudes σMB=0.27; this narrows σMB, corr=0.19 after "correcting" using light-curve "width-luminosity" relation found for nearby (z ≤ 0.1) Type Ia from Calán/Tololo survey (Hamuy et...
This report describes the 2014 study by Science Definition Team (SDT) of Wide-Field Infrared Survey Telescope (WFIRST) mission. It is a space observatory that will address most compelling scientific problems in dark energy, exoplanets and general astrophysics using 2.4-m telescope with wide-field infrared instrument an optical coronagraph. The Astro2010 Decadal recommended Wide Field as its top priority for new large As conceived decadal survey, WFIRST would carry out energy science program,...
The cosmic triangle is introduced as a way of representing the past, present, and future status universe. Our current location within determined by answers to three questions: How much matter in universe? Is expansion rate slowing down or speeding up? And, universe flat? A review recent observations suggests that lightweight (matter density about one-third critical value), accelerating, flat. acceleration implies existence dark energy overcomes gravitational self-attraction causes speed up.
We report on work to increase the number of well-measured Type Ia supernovae (SNe Ia) at high redshifts. Light curves, including signal-to-noise Hubble Space Telescope data, and spectra six SNe that were discovered during 2001, are presented. Additionally, for two with z > 1, we present ground-based J-band photometry from Gemini Very Large Telescope. These among most distant which near-IR observations have been obtained. add these together other data sets recently become available in...
We combine high redshift Type Ia supernovae from the first 3 years of Supernova Legacy Survey (SNLS) with other supernova (SN) samples, primarily at lower redshifts, to form a high-quality joint sample 472 SNe (123 low-$z$, 93 SDSS, 242 SNLS, and 14 {\it Hubble Space Telescope}). SN data alone require cosmic acceleration >99.9% confidence, including systematic effects. For dark energy equation state parameter (assumed constant out least $z=1.4$) in flat universe, we find $w =...
Measurements of the distances to type Ia supernovae have produced strong evidence that expansion Universe is accelerating, implying existence a nearly uniform component dark energy with negative pressure. We show constraints this mysterious based upon large-scale structure nicely complement SN data, and together they require ${\ensuremath{\Omega}}_{X}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}{\ensuremath{\rho}}_{X}/{\ensuremath{\rho}}_{\mathrm{crit}}\ensuremath{\in}(0.6,0.7)$...
Berkeley Earth Temperature Averaging Process A new mathematical framework is presented for producing maps and large-scale averages of temperature changes from weather station thermometer data the purposes climate analysis. The method allows inclusion short discontinuous records, so nearly all digitally archived can be used. uses statistical known as Kriging to interpolate stations arbitrary locations on Earth.
We present observational constraints on the nature of dark energy using Supernova Legacy Survey three-year sample (SNLS3) Guy et al. and Conley use 472 Type Ia supernovae (SNe Ia) in this sample, accounting for recently discovered correlations between SN luminosity host galaxy properties, include effects all identified systematic uncertainties directly cosmological fits. Combining SNLS3 data with full WMAP7 power spectrum, Sloan Digital Sky luminous red a prior Hubble constant H0 from SHOES,...
(Abridged) Precision cosmology with Type Ia supernovae (SNe Ia) makes use of the fact that SN luminosities depend on their light-curve shapes and colours. Using Supernova Legacy Survey (SNLS) other data, we show there is an additional dependence global characteristics host galaxies: events same shape colour are, average, 0.08mag (~4.0sigma) brighter in massive galaxies (presumably metal-rich) low specific star-formation rates (sSFR). SNe a sSFR also have smaller slope ("beta") between...
(ABRIDGED) We show that Type Ia supernovae (SNe Ia) are formed within both very young and old stellar populations, with observed rates depend on the mass mean star-formation (SFRs) of their host galaxies. Models where SN rate depends solely galaxy ruled out 99% confidence. Our analysis is based 100 spectroscopically-confirmed SNe Ia, plus 24 photometrically-classified events, all from Supernova Legacy Survey (SNLS) distributed over 0.2
We present photometric and spectroscopic observations of SN 2007if, an overluminous (MV = −20.4), red (B − V 0.16 at B-band maximum), slow-rising (trise 24 days) type Ia supernova (SN Ia) in a very faint (Mg −14.10) host galaxy. A spectrum 5 days past maximum light is direct match to the super-Chandrasekhar-mass candidate 2003fg, showing Si ii C ∼9000 km s−1. high signal-to-noise co-addition spectral time series reveals no Na i D absorption, suggesting negligible reddening galaxy, late-time...
Previously we used the Nearby Supernova Factory sample to show that Type Ia supernovae (SNe Ia) having locally star-forming environments are dimmer than SNe passive environments. Here use Constitution together with host galaxy data from GALEX independently confirm result. The effect is seen using both SALT2 and MLCS2k2 lightcurve fitting standardization methods, brightness differences of 0.094 ± 0.037 mag for 0.155 0.041 RV = 2.5. When combined our previous measurement 0.025 SALT2. If ratio...
The Wide Field Infrared Survey Telescope (WFIRST) is a 2.4m space telescope with 0.281 deg^2 field of view for near-IR imaging and slitless spectroscopy coronagraph designed > 10^8 starlight suppresion. As background information Astro2020 white papers, this article summarizes the current design anticipated performance WFIRST. While WFIRST does not have UV imaging/spectroscopic capabilities Hubble Space Telescope, wide surveys hundreds times more efficient. Some most ambitious multi-cycle...
As part of an on-going effort to identify, understand and correct for astrophysics biases in the standardization Type Ia supernovae (SNIa) cosmology, we have statistically classified a large sample nearby SNeIa into those located predominantly younger or older environments. This classification is based on specific star formation rate measured within projected distance 1kpc from each SN location (LsSFR). important refinement compared using local directly as it provides normalization relative...