T. M. Davis
A5075733791- Galaxies: Formation, Evolution, Phenomena
- Gamma-ray bursts and supernovae
- Astronomy and Astrophysical Research
- Cosmology and Gravitation Theories
- Stellar, planetary, and galactic studies
- Astrophysics and Cosmic Phenomena
- Pulsars and Gravitational Waves Research
- Astrophysical Phenomena and Observations
- Radio Astronomy Observations and Technology
- Dark Matter and Cosmic Phenomena
- Astronomical Observations and Instrumentation
- Geophysics and Gravity Measurements
- CCD and CMOS Imaging Sensors
- Scientific Research and Discoveries
- Space Science and Extraterrestrial Life
- Adaptive optics and wavefront sensing
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Solar and Space Plasma Dynamics
- Black Holes and Theoretical Physics
- Earth Systems and Cosmic Evolution
- Relativity and Gravitational Theory
- Statistical and numerical algorithms
- Gaussian Processes and Bayesian Inference
- Neutrino Physics Research
The University of Queensland
2016-2025
Indian Institute of Technology Hyderabad
2024
ARC Centre of Excellence for All-sky Astrophysics
2004-2023
Campbell Collaboration
2022
Australian National University
2005-2017
The University of Sydney
2017
Kavli Institute for Particle Astrophysics and Cosmology
2016
Stanford University
2016
NGC Aerospace (Canada)
2016
University of Miami
2015
We present cosmological results from a combined analysis of galaxy clustering and weak gravitational lensing, using 1321 deg$^2$ $griz$ imaging data the first year Dark Energy Survey (DES Y1). combine three two-point functions: (i) cosmic shear correlation function 26 million source galaxies in four redshift bins, (ii) angular autocorrelation 650,000 luminous red five (iii) galaxy-shear cross-correlation positions shears. To demonstrate robustness these results, we use independent pairs...
We present measurements of the baryon acoustic peak at redshifts z = 0.44, 0.6 and 0.73 in galaxy correlation function final dataset WiggleZ Dark Energy Survey. combine our with lower-redshift from 6-degree Field Galaxy Survey Sloan Digital Sky Survey, producing a stacked survey which statistical significance detection is 4.9-sigma relative to zero-baryon model no peak. fit cosmological models this combined oscillation (BAO) comprising six distance-redshift data points, compare results...
We present constraints on the dark energy equation-of-state parameter, w=P/(rho c^2), using 60 Type Ia supernovae (SNe Ia) from ESSENCE supernova survey. derive a set of nature assuming flat Universe. By including (Omega_M, w) baryon acoustic oscillations, we obtain value for static parameter w=-1.05^{+0.13}_{-0.12} (stat; 1 sigma) +- 0.11 (sys) and Omega_M=0.274^{+0.033}_{-0.020} with best-fit chi^2/DoF 0.96. These results are consistent those reported by SuperNova Legacy Survey in similar...
We present the first cosmology results from large-scale structure in Dark Energy Survey (DES) spanning 5000 deg$^2$. perform an analysis combining three two-point correlation functions (3$\times$2pt): (i) cosmic shear using 100 million source galaxies, (ii) galaxy clustering, and (iii) cross-correlation of with lens positions. The was designed to mitigate confirmation or observer bias; we describe specific changes made sample following unblinding results. model data within flat $\Lambda$CDM...
This overview paper describes the legacy prospect and discovery potential of Dark Energy Survey (DES) beyond cosmological studies, illustrating it with examples from DES early data.DES is using a wide-field camera (DECam) on 4 m Blanco Telescope in Chile to image 5000 sq deg sky five filters (grizY).
We present measurements of the Hubble diagram for 103 Type Ia supernovae (SNe) with redshifts 0.04 < z 0.42, discovered during first season (Fall 2005) Sloan Digital Sky Survey-II (SDSS-II) Supernova Survey. These data fill in redshift "desert" between low- and high-redshift SN surveys. combine SDSS-II new distance estimates published from ESSENCE survey, Legacy Survey, Space Telescope, a compilation nearby measurements. Combining Baryon Acoustic Oscillations SDSS Luminous Red Galaxy sample...
We present constraints on cosmological parameters from the Pantheon+ analysis of 1701 light curves 1550 distinct Type Ia supernovae (SNe Ia) ranging in redshift $z=0.001$ to 2.26. This work features an increased sample size, span, and improved treatment systematic uncertainties comparison original Pantheon results a factor two improvement constraining power. For Flat$\Lambda$CDM model, we find $\Omega_M=0.334\pm0.018$ SNe alone. Flat$w_0$CDM measure $w_0=-0.90\pm0.14$ alone, H$_0=73.5\pm1.1$...
The first cosmological results from the ESSENCE supernova survey (Wood-Vasey and coworkers) are extended to a wider range of models including dynamical dark energy nonstandard models. We fold in greater number external data sets such as recent Higher-z release high-redshift supernovae (Riess coworkers), well several complementary probes. Model comparison statistics Bayesian Akaike information criteria applied gauge worth These favor that give good fit with fewer parameters. Based on this...
Abstract We describe the first public data release of Dark Energy Survey, DES DR1, consisting reduced single-epoch images, co-added source catalogs, and associated products services assembled over 3 yr science operations. DR1 is based on optical/near-infrared imaging from 345 distinct nights (2013 August to 2016 February) by Camera mounted 4 m Blanco telescope at Cerro Tololo Inter-American Observatory in Chile. wide-area survey covering ∼5000 deg 2 southern Galactic cap five broad...
We perform a joint determination of the distance-redshift relation and cosmic expansion rate at redshifts z = 0.44, 0.6 0.73 by combining measurements baryon acoustic peak Alcock-Paczynski distortion from galaxy clustering in WiggleZ Dark Energy Survey, using large ensemble mock catalogues to calculate covariance between measurements.We find that D A (z) (1205 ± 114, 1380 95, 1534 107) Mpc H(z) (82.6 7.8, 87.9 6.1, 97.3 7.0) km s -1 these three redshifts.Further our results with other...
The WiggleZ Dark Energy Survey is a survey of 240,000 emission line galaxies in the distant universe, measured with AAOmega spectrograph on 3.9-m Anglo-Australian Telescope (AAT). target are selected using ultraviolet photometry from GALEX satellite, flux limit NUV<22.8 mag. redshift range containing 90% 0.2<z<1.0. primary aim to precisely measure scale baryon acoustic oscillations (BAO) imprinted spatial distribution these at look-back times 4-8 Gyrs. Detailed forecasts indicate will BAO...
Here we present 1701 light curves of 1550 spectroscopically confirmed Type Ia supernovae (SNe Ia) that will be used to infer cosmological parameters as part the Pantheon+ SN analysis and SH0ES (Supernovae H0 for Equation State dark energy) distance-ladder analysis. This effort is one a series works perform an extensive review redshifts, peculiar velocities, photometric calibration, intrinsic-scatter models SNe Ia. The total number curves, which are compiled across 18 different surveys,...
We present precise measurements of the growth rate cosmic structure for redshift range 0.1 < z 0.9, using redshift-space distortions in galaxy power spectrum WiggleZ Dark Energy Survey. Our results, which have a precision around 10 per cent four independent bins, are well fitted by flat Λ cold dark matter (ΛCDM) cosmological model with density parameter Ωm= 0.27. analysis hence indicates that this provides self-consistent description through large-scale perturbations and homogeneous...
We present significant improvements in cosmic distance measurements from the Wig-gleZ Dark Energy Survey, achieved by applying reconstruction of baryonic acoustic feature technique.We show using both data and simulations that technique can often be effective despite patchiness survey, edge effects shot-noise.We investigate three redshift bins range 0.2 < z 1, all find improvement after detection its usage as a standard ruler.We measure model independent measures D V r fid s /r 1716± 83 Mpc,...
Abstract We present a detailed overview of the cosmological surveys that we aim to carry out with Phase 1 Square Kilometre Array (SKA1) and science they will enable. highlight three main surveys: medium-deep continuum weak lensing low-redshift spectroscopic HI galaxy survey over 5 000 deg 2 ; wide deep intensity mapping (IM) 20 from $z = 0.35$ 3; deep, high-redshift IM 100 3$ 6. Taken together, these achieve an array important scientific goals: measuring equation state dark energy \sim...
ABSTRACT We describe updates to the redMaPPer algorithm, a photometric red-sequence cluster finder specifically designed for large surveys. The updated algorithm is applied of Science Verification (SV) data from Dark Energy Survey (DES), and Sloan Digital Sky (SDSS) DR8 set. DES SV catalog locally volume limited contains 786 clusters with richness (roughly equivalent ) . consists 26,311 , sharply increasing threshold as function redshift performance both catalogs shown be excellent,...
This paper presents cosmological results from the final data release of WiggleZ Dark Energy Survey. We perform full analyses different models using power spectra measured at $z=0.22$, 0.41, 0.60, and 0.78, combined with other sets. The limiting factor in this analysis is theoretical modeling galaxy spectrum, including nonlinearities, bias, redshift-space distortions. In we assess several methods for testing them against Gigaparsec simulations (GiggleZ). fit a base set six parameters,...
The Dark Energy Spectroscopic Instrument (DESI) has embarked on an ambitious five-year survey to explore the nature of dark energy with spectroscopy 40 million galaxies and quasars. DESI will determine precise redshifts employ Baryon Acoustic Oscillation method measure distances from nearby universe z > 3.5, as well growth structure probe potential modifications general relativity. In this paper we describe significant instrumentation developed for survey. new includes a wide-field, 3.2-deg...
We present an improved measurement of the Hubble constant (H_0) using 'inverse distance ladder' method, which adds information from 207 Type Ia supernovae (SNe Ia) Dark Energy Survey (DES) at redshift 0.018 < z 0.85 to existing measurements 122 low (z 0.07) SNe (Low-z) and Baryon Acoustic Oscillations (BAOs). Whereas traditional H_0 with use a ladder parallax Cepheid variable stars, inverse relies on absolute BAOs calibrate intrinsic magnitude Ia. find = 67.8 +/- 1.3 km s-1 Mpc-1...
We describe the derivation and validation of redshift distribution estimates their uncertainties for populations galaxies used as weak-lensing sources in Dark Energy Survey (DES) Year 1 cosmological analyses. The Bayesian Photometric Redshift (bpz) code is to assign four bins between z ≈ 0.2 ≈1.3, produce initial lensing-weighted distributions |$n^i_{\rm PZ}(z)\propto \mathrm{d}n^i/\mathrm{d}z$| members bin i. Accurate determination parameters depends critically on knowledge ni, but...
We introduce redMaGiC, an automated algorithm for selecting Luminous Red Galaxies (LRGs). The was specifically developed to minimize photometric redshift uncertainties in large-scale structure studies. redMaGiC achieves this by self-training the color-cuts necessary produce a luminosity-thresholded LRG sample of constant comoving density. demonstrate that photozs are very nearly as accurate best machine-learning based methods, yet they require minimal spectroscopic training, do not suffer...
We describe the Dark Energy Survey (DES) photometric data set assembled from first three years of science operations to support DES Year 3 cosmology analyses, and provide usage notes aimed at broad astrophysics community. Y3 Gold improves on previous releases DES, Y1 Data Release 1 (DES DR1), presenting an expanded curated that incorporates algorithmic developments in image detrending processing, calibration, object classification. comprises nearly 5000 square degrees grizY imaging south...
ABSTRACT We present and characterize the galaxy shape catalogue from first 3 yr of Dark Energy Survey (DES) observations, over an effective area 4143 deg2 southern sky. describe our data analysis process self-calibrating shear measurement pipeline metacalibration, which builds improves upon used in DES Year 1 several aspects. The weak-lensing consists 100 204 026 galaxies, measured riz bands, resulting a weighted source number density neff = 5.59 gal arcmin−2 corresponding noise σe 0.261....
Abstract Over the next 5 yr, Dark Energy Spectroscopic Instrument (DESI) will use 10 spectrographs with 5000 fibers on 4 m Mayall Telescope at Kitt Peak National Observatory to conduct first Stage IV dark energy galaxy survey. At z < 0.6, DESI Bright Galaxy Survey (BGS) produce most detailed map of universe during dark-energy-dominated epoch redshifts >10 million galaxies spanning 14,000 deg 2 . In this work, we present and validate final BGS target selection survey design. From Legacy...