23 research outputs found

    Dark Energy Survey Year 3 results: Curved-sky weak lensing mass map reconstruction

    Get PDF
    We present reconstructed convergence maps, mass maps, from the Dark Energy Survey (DES) third year (Y3) weak gravitational lensing data set. The mass maps are weighted projections of the density field (primarily dark matter) in the foreground of the observed galaxies. We use four reconstruction methods, each is a maximum a posteriori estimate with a different model for the prior probability of the map: Kaiser-Squires, null B-mode prior, Gaussian prior, and a sparsity prior. All methods are implemented on the celestial sphere to accommodate the large sky coverage of the DES Y3 data. We compare the methods using realistic Lambda CDM simulations with mock data that are closely matched to the DES Y3 data. We quantify the performance of the methods at the map level and then apply the reconstruction methods to the DES Y3 data, performing tests for systematic error effects. The maps are compared with optical foreground cosmic-web structures and are used to evaluate the lensing signal from cosmic-void profiles. The recovered dark matter map covers the largest sky fraction of any galaxy weak lensing map to date

    Dark energy survey year 1 results: The lensing imprint of cosmic voids on the cosmic microwave background

    Get PDF
    Cosmic voids gravitationally lens the cosmic microwave background (CMB) radiation, resulting in a distinct imprint on degree scales. We use the simulated CMB lensing convergence map from the Marenostrum Institut de Ciencias de l’Espai (MICE) N-body simulation to calibrate our detection strategy for a given void definition and galaxy tracer density. We then identify cosmic voids in Dark Energy Survey (DES) Year 1 data and stack the Planck 2015 lensing convergence map on their locations, probing the consistency of simulated and observed void lensing signals. When fixing the shape of the stacked convergence profile to that calibrated from simulations, we find imprints at the 3σ significance level for various analysis choices. The best measurement strategies based on the MICE calibration process yield S/N ≈ 4 for DES Y1, and the best-fitting amplitude recovered from the data is consistent with expectations from MICE (A ≈ 1). Given these results as well as the agreement between them and N-body simulations, we conclude that the previously reported excess integrated Sachs–Wolfe (ISW) signal associated with cosmic voids in DES Y1 has no counterpart in the Planck CMB lensing map.This work has made use of CosmoHub (see Carretero et al. 2017). CosmoHub has been developed by the Port d’Informacio Cient ´ ´ıfica (PIC), maintained through a collaboration of the Institut de F´ısica d’Altes Energies (IFAE) and the Centro de Investigaciones Energeticas, Medioambientales y Tecnol ´ ogicas (CIEMAT), and was ´ partially funded by the ‘Plan Estatal de Investigacion Cient ´ ´ıfica y Tecnica y de Innovaci ´ on’ program of the Spanish government. ´ Funding for the DES Projects has been provided by the US Department of Energy, the US National Science Foundation, the Ministry of Science and Education of Spain, the Science and Technology Facilities Council of the United Kingdom, the Higher Education Funding Council for England, the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign, the Kavli Institute of Cosmological Physics at the University of Chicago, the Center for Cosmology and Astro-Particle Physics at the Ohio State University, the Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University, Financiadora de Estudos e Projetos, Fundac¸ao Carlos Chagas Filho de Amparo ˜ a Pesquisa do ` Estado do Rio de Janeiro, Conselho Nacional de Desenvolvimento Cient´ıfico e Tecnologico and the Minist ´ erio da Ci ´ encia, Tecnologia ˆ e Inovac¸ao, the Deutsche Forschungsgemeinschaft, and the Collab- ˜ orating Institutions in the Dark Energy Survey. The Collaborating Institutions are Argonne National Laboratory, the University of California at Santa Cruz, the University of Cambridge, Centro de Investigaciones Energeticas, Medioambien- ´ tales y Tecnologicas-Madrid, the University of Chicago, Univer- ´ sity College London, the DES-Brazil Consortium, the University of Edinburgh, the Eidgenossische Technische Hochschule (ETH) ¨ Zurich, Fermi National Accelerator Laboratory, the University of ¨ Illinois at Urbana-Champaign, the Institut de Ciencies de l’Espai ` (IEEC/CSIC), the Institut de F´ısica d’Altes Energies, Lawrence Berkeley National Laboratory, the Ludwig-Maximilians Universitat¨ Munchen and the associated Excellence Cluster Universe, the Uni- ¨ versity of Michigan, the National Optical Astronomy Observatory, the University of Nottingham, The Ohio State University, the University of Pennsylvania, the University of Portsmouth, SLAC National Accelerator Laboratory, Stanford University, the University of Sussex, Texas A&M University, and the OzDES Membership Consortium. This paper is based in part on observations at Cerro Tololo InterAmerican Observatory, National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. The DES data management system is supported by the National Science Foundation under Grant Numbers AST-1138766 and AST-1536171. The DES participants from Spanish institutions are partially supported by MINECO under grants AYA2015- 71825, ESP2015-66861, FPA2015-68048, SEV-2016-0588, SEV2016-0597, and MDM-2015-0509, some of which include ERDF funds from the European Union. IFAE is partially funded by the CERCA program of the Generalitat de Catalunya. Research leading to these results has received funding from the European Research Council under the European Union’s Seventh Framework Program (FP7/2007-2013) including ERC grant agreements 240672, 291329, 306478, and 615929. We acknowledge support from the Brazilian Instituto Nacional de Cienciae Tecnologia ˆ (INCT) e-Universe (CNPq grant 465376/2014-2). This paper has been authored by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the US Department of Energy, Office of Science, Office of High Energy Physics. PV acknowledges the support from the grant MIUR PRIN 2015 ‘Cosmology and Fundamental Physics: illuminating the Dark Universe with Euclid’. AK has been supported by a Juan de la Cierva fellowship from MINECO with project number IJC2018-037730-I. Funding for this project was also available in part through SEV-2015-0548 and AYA2017-89891-P. This project has also received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 754558.Peer reviewe

    Dark energy survey year 1 results: The lensing imprint of cosmic voids on the cosmic microwave background

    Get PDF
    Cosmic voids gravitationally lens the cosmic microwave background (CMB) radiation, resulting in a distinct imprint on degree scales. We use the simulated CMB lensing convergence map from the Marenostrum Institut de Ciencias de l’Espai (MICE) N-body simulation to calibrate our detection strategy for a given void definition and galaxy tracer density. We then identify cosmic voids in Dark Energy Survey (DES) Year 1 data and stack the Planck 2015 lensing convergence map on their locations, probing the consistency of simulated and observed void lensing signals. When fixing the shape of the stacked convergence profile to that calibrated from simulations, we find imprints at the 3σ significance level for various analysis choices. The best measurement strategies based on the MICE calibration process yield S/N ≈ 4 for DES Y1, and the best-fitting amplitude recovered from the data is consistent with expectations from MICE (A ≈ 1). Given these results as well as the agreement between them and N-body simulations, we conclude that the previously reported excess integrated Sachs–Wolfe (ISW) signal associated with cosmic voids in DES Y1 has no counterpart in the Planck CMB lensing map

    Dark Energy Survey Year 3 results: Curved-sky weak lensing mass map reconstruction

    Get PDF
    We present reconstructed convergence maps, mass maps, from the Dark Energy Survey (DES) third year (Y3) weak gravitational lensing data set. The mass maps are weighted projections of the density field (primarily dark matter) in the foreground of the observed galaxies. We use four reconstruction methods, each is a maximum a posteriori estimate with a different model for the prior probability of the map: Kaiser-Squires, null B-mode prior, Gaussian prior, and a sparsity prior. All methods are implemented on the celestial sphere to accommodate the large sky coverage of the DES Y3 data. We compare the methods using realistic \u39bCDM simulations with mock data that are closely matched to the DES Y3 data. We quantify the performance of the methods at the map level and then apply the reconstruction methods to the DES Y3 data, performing tests for systematic error effects. The maps are compared with optical foreground cosmic-web structures and are used to evaluate the lensing signal from cosmic-void profiles. The recovered dark matter map covers the largest sky fraction of any galaxy weak lensing map to date

    Dark energy survey year 1 results: The lensing imprint of cosmic voids on the cosmic microwave background

    No full text
    Cosmic voids gravitationally lens the cosmic microwave background (CMB) radiation, resulting in a distinct imprint on degree scales. We use the simulated CMB lensing convergence map from the Marenostrum Institut de Ciencias de l’Espai (MICE) N-body simulation to calibrate our detection strategy for a given void definition and galaxy tracer density. We then identify cosmic voids in Dark Energy Survey (DES) Year 1 data and stack the Planck 2015 lensing convergence map on their locations, probing the consistency of simulated and observed void lensing signals. When fixing the shape of the stacked convergence profile to that calibrated from simulations, we find imprints at the 3σ significance level for various analysis choices. The best measurement strategies based on the MICE calibration process yield S/N ≈ 4 for DES Y1, and the best-fitting amplitude recovered from the data is consistent with expectations from MICE (A ≈ 1). Given these results as well as the agreement between them and N-body simulations, we conclude that the previously reported excess integrated Sachs–Wolfe (ISW) signal associated with cosmic voids in DES Y1 has no counterpart in the Planck CMB lensing map

    The Gravitational Lensing Imprints of DES Y3 Superstructures on the CMB: A Matched Filtering Approach

    No full text
    International audience Low density cosmic voids gravitationally lens the cosmic microwave background (CMB), leaving a negative imprint on the CMB convergence κ\kappa. This effect provides insight into the distribution of matter within voids, and can also be used to study the growth of structure. We measure this lensing imprint by cross-correlating the Planck CMB lensing convergence map with voids identified in the Dark Energy Survey Year 3 data set, covering approximately 4,200 deg2^2 of the sky. We use two distinct void-finding algorithms: a 2D void-finder which operates on the projected galaxy density field in thin redshift shells, and a new code, Voxel, which operates on the full 3D map of galaxy positions. We employ an optimal matched filtering method for cross-correlation, using the MICE N-body simulation both to establish the template for the matched filter and to calibrate detection significances. Using the DES Y3 photometric luminous red galaxy sample, we measure AκA_\kappa, the amplitude of the observed lensing signal relative to the simulation template, obtaining Aκ=1.03±0.22A_\kappa = 1.03 \pm 0.22 (4.6σ4.6\sigma significance) for Voxel and Aκ=1.02±0.17A_\kappa = 1.02 \pm 0.17 (5.9σ5.9\sigma significance) for 2D voids, both consistent with Λ\LambdaCDM expectations. We additionally invert the 2D void-finding process to identify superclusters in the projected density field, for which we measure Aκ=0.87±0.15A_\kappa = 0.87 \pm 0.15 (5.9σ5.9\sigma significance). The leading source of noise in our measurements is Planck noise, implying that future data from the Atacama Cosmology Telescope (ACT), South Pole Telescope (SPT) and CMB-S4 will increase sensitivity and allow for more precise measurements

    The Gravitational Lensing Imprints of DES Y3 Superstructures on the CMB: A Matched Filtering Approach

    No full text
    International audience Low density cosmic voids gravitationally lens the cosmic microwave background (CMB), leaving a negative imprint on the CMB convergence κ\kappa. This effect provides insight into the distribution of matter within voids, and can also be used to study the growth of structure. We measure this lensing imprint by cross-correlating the Planck CMB lensing convergence map with voids identified in the Dark Energy Survey Year 3 data set, covering approximately 4,200 deg2^2 of the sky. We use two distinct void-finding algorithms: a 2D void-finder which operates on the projected galaxy density field in thin redshift shells, and a new code, Voxel, which operates on the full 3D map of galaxy positions. We employ an optimal matched filtering method for cross-correlation, using the MICE N-body simulation both to establish the template for the matched filter and to calibrate detection significances. Using the DES Y3 photometric luminous red galaxy sample, we measure AκA_\kappa, the amplitude of the observed lensing signal relative to the simulation template, obtaining Aκ=1.03±0.22A_\kappa = 1.03 \pm 0.22 (4.6σ4.6\sigma significance) for Voxel and Aκ=1.02±0.17A_\kappa = 1.02 \pm 0.17 (5.9σ5.9\sigma significance) for 2D voids, both consistent with Λ\LambdaCDM expectations. We additionally invert the 2D void-finding process to identify superclusters in the projected density field, for which we measure Aκ=0.87±0.15A_\kappa = 0.87 \pm 0.15 (5.9σ5.9\sigma significance). The leading source of noise in our measurements is Planck noise, implying that future data from the Atacama Cosmology Telescope (ACT), South Pole Telescope (SPT) and CMB-S4 will increase sensitivity and allow for more precise measurements

    Dark Energy Survey Year 1 Results: the lensing imprint of cosmic voids on the Cosmic Microwave Background

    No full text
    Cosmic voids gravitationally lens the cosmic microwave background (CMB) radiation, resulting in a distinct imprint on degree scales. We use the simulated CMB lensing convergence map from the MICE N-body simulation to calibrate our detection strategy for a given void definition and galaxy tracer density. We then identify cosmic voids in DES Year 1 data and stack the Planck 2015 lensing convergence map on their locations, probing the consistency of simulated and observed void lensing signals. When fixing the shape of the stacked convergence profile to that calibrated from simulations, we find imprints at the 3\u3c3 significance level for various analysis choices. The best measurement strategies based on the MICE calibration process yield S/N 48 4 for DES Y1, and the best-fit amplitude recovered from the data is consistent with expectations from MICE (A 48 1). Given these results as well as the agreement between them and N-body simulations, we conclude that the previously reported excess integrated Sachs-Wolfe (ISW) signal associated with cosmic voids in DES Y1 has no counterpart in the Planck CMB lensing map

    Dark Energy Survey Year 3 results: imprints of cosmic voids and superclusters in the Planck CMB lensing map

    Get PDF
    The CMB lensing signal from cosmic voids and superclusters probes the growth of structure in the low-redshift cosmic web. In this analysis, we cross-correlated the Planck CMB lensing map with voids detected in the Dark Energy Survey Year 3 (Y3) data set (\sim5,000 deg2^{2}), extending previous measurements using Y1 catalogues (\sim1,300 deg2^{2}). Given the increased statistical power compared to Y1 data, we report a 6.6σ6.6\sigma detection of negative CMB convergence (κ\kappa) imprints using approximately 3,600 voids detected from a redMaGiC luminous red galaxy sample. However, the measured signal is lower than expected from the MICE N-body simulation that is based on the Λ\LambdaCDM model (parameters Ωm=0.25\Omega_{\rm m} = 0.25, σ8=0.8\sigma_8 = 0.8). The discrepancy is associated mostly with the void centre region. Considering the full void lensing profile, we fit an amplitude Aκ=κDES/κMICEA_{\kappa}=\kappa_{\rm DES}/\kappa_{\rm MICE} to a simulation-based template with fixed shape and found a moderate 2σ2\sigma deviation in the signal with Aκ0.79±0.12A_{\kappa}\approx0.79\pm0.12. We also examined the WebSky simulation that is based on a Planck 2018 Λ\LambdaCDM cosmology, but the results were even less consistent given the slightly higher matter density fluctuations than in MICE. We then identified superclusters in the DES and the MICE catalogues, and detected their imprints at the 8.4σ8.4\sigma level; again with a lower-than-expected Aκ=0.84±0.10A_{\kappa}=0.84\pm0.10 amplitude. The combination of voids and superclusters yields a 10.3σ10.3\sigma detection with an Aκ=0.82±0.08A_{\kappa}=0.82\pm0.08 constraint on the CMB lensing amplitude, thus the overall signal is 2.3σ2.3\sigma weaker than expected from MICE
    corecore