T. Jeltema
A5007311582- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Dark Matter and Cosmic Phenomena
- Cosmology and Gravitation Theories
- Gamma-ray bursts and supernovae
- Astrophysics and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- Astronomical Observations and Instrumentation
- Radio Astronomy Observations and Technology
- Scientific Research and Discoveries
- Adaptive optics and wavefront sensing
- CCD and CMOS Imaging Sensors
- Astrophysics and Star Formation Studies
- Particle physics theoretical and experimental studies
- Pulsars and Gravitational Waves Research
- Particle Detector Development and Performance
- Impact of Light on Environment and Health
- Remote Sensing in Agriculture
- Gaussian Processes and Bayesian Inference
- Medical Imaging Techniques and Applications
- Calibration and Measurement Techniques
- Plant Water Relations and Carbon Dynamics
- Statistical and numerical algorithms
- Geophysics and Sensor Technology
University of California, Santa Cruz
2015-2024
University of Hull
2023
Campbell Collaboration
2021
University of Southampton
2021
Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas
2021
Oak Ridge National Laboratory
2021
Northwestern University
2017
Carnegie Observatories
2005-2010
Morrison Tech
2008
Carnegie Institution for Science
2006
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 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...
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 use 26×106 galaxies from the Dark Energy Survey (DES) Year 1 shape catalogs over 1321 deg2 of sky to produce most significant measurement cosmic shear in a galaxy survey date. constrain cosmological parameters both flat ΛCDM and wCDM models, while also varying neutrino mass density. These results are shown be robust using two independent catalogs, photo-z calibration methods, analysis pipelines blind analysis. find 3.5% fractional uncertainty on σ8(Ωm/0.3)0.5=0.782+0.027−0.027 at 68%...
Satellite galaxies of the Milky Way are among most promising targets for dark matter searches in gamma rays. We present a search consisting weakly interacting massive particles, applying joint likelihood analysis to 10 satellite with 24 months data Fermi Large Area Telescope. No signal is detected. Including uncertainty distribution, robust upper limits placed on annihilation cross sections. The 95% confidence level range from about 10(-26) cm3 s(-1) at 5 GeV 5×10(-23) 1 TeV, depending final...
We present a comprehensive review of keV-scale sterile neutrino Dark Matter, collecting views and insights from all disciplines involved - cosmology, astrophysics, nuclear, particle physics in each case viewed both theoretical experimental/observational perspectives. After reviewing the role active neutrinos physics, we focus on context Matter puzzle. Here, first motivation for based challenges tensions purely cold scenarios. then round out discussion by critically summarizing known...
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,...
We combine Dark Energy Survey Year 1 clustering and weak lensing data with Baryon Acoustic Oscillations (BAO) Big Bang Nucleosynthesis (BBN) experiments to constrain the Hubble constant. Assuming a flat $\Lambda$CDM model minimal neutrino mass ($\sum m_\nu = 0.06$ eV) we find $H_0=67.2^{+1.2}_{-1.0}$ km/s/Mpc (68% CL). This result is completely independent of constant measurements based on distance ladder, Cosmic Microwave Background (CMB) anisotropies (both temperature polarization), strong...
We describe the creation, content, and validation of Dark Energy Survey (DES) internal year-one cosmology data set, Y1A1 GOLD, in support upcoming cosmological analyses. The GOLD set is assembled from multiple epochs DES imaging consists calibrated photometric zeropoints, object catalogs, ancillary products - e.g., maps survey depth observing conditions, star-galaxy classification, redshift estimates that are necessary for accurate wide-area catalog ~137 million objects detected coadded...
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...
Due to their proximity, high dark-matter content, and apparent absence of non-thermal processes, Milky Way dwarf spheroidal satellite galaxies (dSphs) are excellent targets for the indirect detection dark matter. Recently, eight new dSph candidates were discovered using first year data from Dark Energy Survey (DES). We searched gamma-ray emission coincident with positions these objects in six years Fermi Large Area Telescope data. found no significant excesses emission. Under assumption that...
We constrain the mass–richness scaling relation of redMaPPer galaxy clusters identified in Dark Energy Survey Year 1 data using weak gravitational lensing. split into 4 × 3 bins richness λ and redshift |$z$| for ≥ 20 0.2 ≤ 0.65 measure mean masses these their stacked lensing signal. By modelling as 〈M200m|λ, |$z$|〉 = M0(λ/40)F((1 + |$z$|)/1.35)G, we normalization at 5.0 per cent level, finding M0 [3.081 ± 0.075(stat) 0.133(sys)] · 1014 M⊙ 40 0.35. The recovered index is F 1.356 0.051 (stat)...
We present two galaxy shape catalogues from the Dark Energy Survey Year 1 data set, covering 1500 square degrees with a median redshift of $0.59$. The cover main fields: Stripe 82, and an area overlapping South Pole Telescope survey region. describe our analysis process in particular measurement using independent shear pipelines, METACALIBRATION IM3SHAPE. catalogue uses Gaussian model innovative internal calibration scheme, was applied to $riz$-bands, yielding 34.8M objects. IM3SHAPE...
We present constraints on extensions of the minimal cosmological models dominated by dark matter and energy, $\Lambda$CDM $w$CDM, using a combined analysis galaxy clustering weak gravitational lensing from first-year data Dark Energy Survey (DES Y1) in combination with external data. consider four energy-dominated scenarios: 1) nonzero curvature $\Omega_k$, 2) number relativistic species $N_{\rm eff}$ different standard value 3.046, 3) time-varying equation-of-state energy described...
ABSTRACT We present a blind time-delay cosmographic analysis for the lens system DES J0408−5354. This is extraordinary presence of two sets multiple images at different redshifts, which provide opportunity to obtain more information cost increased modelling complexity with respect previously analysed systems. perform detailed mass distribution this using three band Hubble Space Telescope imaging. combine measured time delays, line-of-sight central velocity dispersion deflector, and...
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 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 angular diameter distance measurements obtained by locating the baryon acoustic oscillations (BAO) scale in distribution of galaxies selected from first year Dark Energy Survey data. consider a sample over 1.3 million distributed footprint 1336 deg2 with 0.6 < $z$photo 1 and typical redshift uncertainty 0.03(1 + $z$). This was selected, as fully described companion paper, using colour/magnitude selection that optimizes trade-offs between number density uncertainty....
Microlensing of stars places significant constraints on subplanetary-mass compact objects, including primordial black holes, as dark matter candidates. As the lens' Einstein radius in source plane becomes comparable to size light source, however, amplification is strongly suppressed, making it challenging constrain lenses with a mass at or below ${10}^{\ensuremath{-}10}$ solar masses, i.e., asteroid-mass objects. Current constraints, using Subaru Hyper Suprime Cam (HSC) observations M31,...
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....
We present a joint cosmic shear analysis of the Dark Energy Survey (DES Y3) and Kilo-Degree (KiDS-1000) in collaborative effort between two survey teams. find consistent cosmological parameter constraints DES Y3 KiDS-1000 which, when combined joint-survey analysis, constrain $S_8 = \sigma_8 \sqrt{\Omega_{\rm m}/0.3}$ with mean value $0.790^{+0.018}_{-0.014}$. The marginal is lower than maximum posteriori estimate, $S_8=0.801$, owing to skewness distribution projection effects...
We present angular diameter measurements obtained by measuring the position of Baryon Acoustic Oscillations (BAO) in an optimised sample galaxies from first three years Dark Energy Survey data (DES Y3). The consists 7 million distributed over a footprint 4100 deg$^2$ with $0.6 < z_{\rm photo} 1.1$ and typical redshift uncertainty $0.03(1+z)$. selection is same as BAO measurement year DES data, but analysis presented here uses times area, extends to higher makes number improvements, including...
The authors use Dark Energy Survey data on galaxy clustering and lensing from the first three years of observations combined with five prominent external datasets. They robustly constrain six potential extensions to currently prevalent cosmological paradigm \ensuremath{\Lambda}CDM (Cold Matter a constant). All would add significant new physics, such as deviations General Relativity or non-zero spatial curvature, but no evidence for physics is found.
We present cosmological constraints from the analysis of two-point correlation functions between galaxy positions and lensing measured in Dark Energy Survey (DES) Year 3 data measurements cosmic microwave background (CMB) South Pole Telescope (SPT) Planck. When jointly analyzing DES-only DES cross-correlations with SPT+Planck CMB lensing, we find Ωm=0.344±0.030 S8≡σ8(Ωm/0.3)0.5=0.773±0.016, assuming ΛCDM. additionally combining autospectrum, Ωm=0.306+0.018−0.021 S8=0.792±0.012. The high...
We report on the observations of 14 dwarf spheroidal galaxies with Fermi Gamma-Ray Space Telescope taken during first 11 months survey mode operations. The telescope provides a new opportunity to test particle dark matter models through expected gamma-ray emission produced by pair annihilation weakly interacting massive particles (WIMPs). Local Group galaxies, largest galactic substructures predicted cold scenario, are attractive targets for such indirect searches because they nearby and...