Mike Jarvis
A5072520692- Global trade and economics
- Global Financial Crisis and Policies
- Galaxies: Formation, Evolution, Phenomena
- Economic Theory and Policy
- Astronomy and Astrophysical Research
- Cosmology and Gravitation Theories
- International Development and Aid
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Dark Matter and Cosmic Phenomena
- Global Financial Regulation and Crises
- CCD and CMOS Imaging Sensors
- Radio Astronomy Observations and Technology
- Stellar, planetary, and galactic studies
- Canadian Policy and Governance
- Astrophysics and Cosmic Phenomena
- Astronomical Observations and Instrumentation
- Gaussian Processes and Bayesian Inference
- Remote Sensing in Agriculture
- Astrophysical Phenomena and Observations
- Geophysics and Gravity Measurements
- Calibration and Measurement Techniques
- Scientific Research and Discoveries
- Statistical and numerical algorithms
- Optical measurement and interference techniques
University of Pennsylvania
2016-2025
California University of Pennsylvania
2008-2025
University of Rochester
2022
University of Oxford
2005-2021
University of the Western Cape
2012-2021
Campbell Collaboration
2021
Institute of Space Sciences
2016
Schlumberger (British Virgin Islands)
2015
Philadelphia University
2014
Imperial College London
2013
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...
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%...
The Shear TEsting Programme, STEP, is a collaborative project to improve the accuracy and reliability of all weak lensing measurements in preparation for next generation wide-field surveys. In this first STEP paper we present results blind analysis simulated ground-based observations relatively simple galaxy morphologies. most successful methods are shown achieve percent level accuracy. From cosmic shear pipelines that have been used constrain cosmology, find measured an within statistical...
This work, together with its companion paper, Secco and Samuroff et al. (2021), presents the Dark Energy Survey Year 3 cosmic shear measurements cosmological constraints based on an analysis of over 100 million source galaxies. With data spanning 4143 deg$^2$ sky, divided into four redshift bins, we produce highest significance measurement to date, a signal-to-noise 40. We conduct blind in context $\Lambda$CDM model find 3% constraint clustering amplitude, $S_8\equiv \sigma_8 (\Omega_{\rm...
This work and its companion paper, Amon et al. (2021), present cosmic shear measurements cosmological constraints from over 100 million source galaxies in the Dark Energy Survey (DES) Year 3 data. We constrain lensing amplitude parameter $S_8\equiv\sigma_8\sqrt{\Omega_\textrm{m}/0.3}$ at 3% level $\Lambda$CDM: $S_8=0.759^{+0.025}_{-0.023}$ (68% CL). Our constraint is 2% when using angular scale cuts that are optimized for $\Lambda$CDM analysis: $S_8=0.772^{+0.018}_{-0.017}$ With alone, we...
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 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 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 present the first constraints on cosmology from Dark Energy Survey (DES), using weak lensing measurements preliminary Science Verification (SV) data. use 139 square degrees of SV data, which is less than 3% full DES survey area. Using cosmic shear 2-point over three redshift bins we find ${\ensuremath{\sigma}}_{8}({\mathrm{\ensuremath{\Omega}}}_{\mathrm{m}}/0.3{)}^{0.5}=0.81\ifmmode\pm\else\textpm\fi{}0.06$ (68% confidence), after marginalizing 7 systematics parameters and 3 other...
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 present weak lensing shear catalogues for 139 square degrees of data taken during the Science Verification (SV) time new Dark Energy Camera (DECam) being used Survey (DES). describe our object selection, point spread function estimation and measurement procedures using two independent pipelines, im3shape ngmix, which produce 2.12 million 3.44 galaxies, respectively. detail a set null tests measurements find that they pass requirements systematic errors at level necessary science...
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....
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...
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 present the theoretical and analytical bases of optimal techniques to measure weak gravitational shear from images galaxies. first characterize geometric space shears ellipticity then use this interpretation analyze images. The steps analysis include measurement object shapes on images, combining measurements a given galaxy different estimating underlying an ensemble shapes, compensating for systematic effects image distortion, bias point-spread function (PSF) asymmetries, "dilution"...
The Shear TEsting Programme (STEP) is a collaborative project to improve the accuracy and reliability of weak lensing measurement, in preparation for next generation wide-field surveys. We review sixteen current emerging shear measurement methods common language, assess their performance by running them (blindly) on simulated images that contain known signal. determine features algorithms most successfully recover input parameters. achieve previously unattained discriminatory precision our...
We present the results of GREAT08 Challenge, a blind analysis challenge to infer weak gravitational lensing shear distortions from images. The primary goal was stimulate new ideas by presenting problem researchers outside measurement community. Six Team methods were presented at launch Challenge and five additional groups submitted during 6 month competition. Participants analyzed 30 million simulated galaxies with range in signal noise ratio, point-spread function ellipticity, galaxy size,...
We present photometric redshift estimates for galaxies used in the weak lensing analysis of Dark Energy Survey Science Verification (DES SV) data. Four model- or machine learning-based methods -- ANNZ2, BPZ calibrated against BCC-Ufig simulations, SkyNet, and TPZ are analysed. For training, calibration, testing these methods, we construct a catalogue spectroscopically confirmed matched DES SV The performance is evaluated spectroscopic catalogue, focusing on metrics relevant analyses, with...
We measure the clustering of DES Year 1 galaxies that are intended to be combined with weak lensing samples in order produce precise cosmological constraints from joint analysis large-scale structure and correlations. Two-point correlation functions measured for a sample $6.6 \times 10^{5}$ luminous red selected using \textsc{redMaGiC} algorithm over an area $1321$ square degrees, redshift range $0.15 < z 0.9$, split into five tomographic bins. The has mean uncertainty $\sigma_{z}/(1+z) =...
Shear peak statistics has gained a lot of attention recently as practical alternative to the two point for constraining cosmological parameters. We perform shear analysis Dark Energy Survey (DES) Science Verification (SV) data, using weak gravitational lensing measurements from 139 deg$^2$ field. measure abundance peaks identified in aperture mass maps, function their signal-to-noise ratio, range $0<\mathcal S / \mathcal N<4$. To predict counts parameters we use suite $N$-body simulations...