skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Dark Energy Survey Year 1 results: the impact of galaxy neighbours on weak lensing cosmology with IM3SHAPE

Abstract

In this work, we use a suite of simulated images based on Year 1 of the Dark Energy Survey to explore the impact of galaxy neighbours on shape measurement and shear cosmology. The hoopoe image simulations include realistic blending, galaxy positions, and spatial variations in depth and point spread function properties. Using the im3shape maximum-likelihood shape measurement code, we identify four mechanisms by which neighbours can have a non-negligible influence on shear estimation. These effects, if ignored, would contribute a net multiplicative bias of m ~0.03–0.09 in the Year One of the Dark Energy Survey (DES Y1) im3shape catalogue, though the precise impact will be dependent on both the measurement code and the selection cuts applied. This can be reduced to percentage level or less by removing objects with close neighbours, at a cost to the effective number density of galaxies neff of 30 percent. We use the cosmological inference pipeline of DES Y1 to explore the cosmological implications of neighbour bias and show that omitting blending from the calibration simulation for DES Y1 would bias the inferred clustering amplitude S8 ≡ σ8(Ωm/0.3)0.5 by 2σ towards low values. Lastly, we use the hoopoe simulations to test the effect of neighbour-inducedmore » spatial correlations in the multiplicative bias. We find the impact on the recovered S8 of ignoring such correlations to be subdominant to statistical error at the current level of precision.« less

Authors:
 [1]
  1. Univ. of Manchester (United Kingdom). et al.
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP); USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR)
Contributing Org.:
DES Collaboration
OSTI Identifier:
1376073
Alternate Identifier(s):
OSTI ID: 1392237; OSTI ID: 1426560
Report Number(s):
FERMILAB-PUB-17-291-E; arXiv:1708.01534; BNL-114252-2017-JA
Journal ID: ISSN 0035-8711; 1614457
Grant/Contract Number:  
AC02-07CH11359; SC0012704; AC05-00OR22725
Resource Type:
Accepted Manuscript
Journal Name:
Monthly Notices of the Royal Astronomical Society
Additional Journal Information:
Journal Volume: 475; Journal Issue: 4; Journal ID: ISSN 0035-8711
Publisher:
Royal Astronomical Society
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; gravitational lensing: weak; galaxies: statistics; cosmological parameters; cosmology: observations

Citation Formats

Samuroff, S. Dark Energy Survey Year 1 results: the impact of galaxy neighbours on weak lensing cosmology with IM3SHAPE. United States: N. p., 2017. Web. https://doi.org/10.1093/mnras/stx3282.
Samuroff, S. Dark Energy Survey Year 1 results: the impact of galaxy neighbours on weak lensing cosmology with IM3SHAPE. United States. https://doi.org/10.1093/mnras/stx3282
Samuroff, S. Tue . "Dark Energy Survey Year 1 results: the impact of galaxy neighbours on weak lensing cosmology with IM3SHAPE". United States. https://doi.org/10.1093/mnras/stx3282. https://www.osti.gov/servlets/purl/1376073.
@article{osti_1376073,
title = {Dark Energy Survey Year 1 results: the impact of galaxy neighbours on weak lensing cosmology with IM3SHAPE},
author = {Samuroff, S.},
abstractNote = {In this work, we use a suite of simulated images based on Year 1 of the Dark Energy Survey to explore the impact of galaxy neighbours on shape measurement and shear cosmology. The hoopoe image simulations include realistic blending, galaxy positions, and spatial variations in depth and point spread function properties. Using the im3shape maximum-likelihood shape measurement code, we identify four mechanisms by which neighbours can have a non-negligible influence on shear estimation. These effects, if ignored, would contribute a net multiplicative bias of m ~0.03–0.09 in the Year One of the Dark Energy Survey (DES Y1) im3shape catalogue, though the precise impact will be dependent on both the measurement code and the selection cuts applied. This can be reduced to percentage level or less by removing objects with close neighbours, at a cost to the effective number density of galaxies neff of 30 percent. We use the cosmological inference pipeline of DES Y1 to explore the cosmological implications of neighbour bias and show that omitting blending from the calibration simulation for DES Y1 would bias the inferred clustering amplitude S8 ≡ σ8(Ωm/0.3)0.5 by 2σ towards low values. Lastly, we use the hoopoe simulations to test the effect of neighbour-induced spatial correlations in the multiplicative bias. We find the impact on the recovered S8 of ignoring such correlations to be subdominant to statistical error at the current level of precision.},
doi = {10.1093/mnras/stx3282},
journal = {Monthly Notices of the Royal Astronomical Society},
number = 4,
volume = 475,
place = {United States},
year = {2017},
month = {12}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 15 works
Citation information provided by
Web of Science

Figures / Tables:

Figure-1 Figure-1: Postage stamp snapshots of the basic two-object toy model described in Section 3. The overlain ellipse shows the maximum likelihood fit to the image. The panels show three neighbour positions in the range θ = [0, π/2] rad. The best-fitting ellipticity and half-light radius are shown above each image.more » In all cases the input values are e = (0, 0), r = 0.5 arcsec.« less

Save / Share:

Works referenced in this record:

Cosmology from cosmic shear with Dark Energy Survey Science Verification data
journal, July 2016


CFHTLenS: the Canada–France–Hawaii Telescope Lensing Survey: CFHTLenS
journal, October 2012

  • Heymans, Catherine; Van Waerbeke, Ludovic; Miller, Lance
  • Monthly Notices of the Royal Astronomical Society, Vol. 427, Issue 1
  • DOI: 10.1111/j.1365-2966.2012.21952.x

Detection of Cosmic Shear with the [ITAL]Hubble Space Telescope[/ITAL] Survey Strip
journal, May 2001

  • Rhodes, Jason; Refregier, Alexandre; Groth, Edward J.
  • The Astrophysical Journal, Vol. 552, Issue 2
  • DOI: 10.1086/320336

A bias in cosmic shear from galaxy selection: results from ray-tracing simulations
journal, February 2011


Practical Weak-lensing Shear Measurement with Metacalibration
journal, May 2017


Cosmic Shear Results from the deep lens Survey. ii. full Cosmological Parameter Constraints from Tomography
journal, June 2016


Dark Energy Constraints from the CTIO Lensing Survey
journal, June 2006

  • Jarvis, Mike; Jain, Bhuvnesh; Bernstein, Gary
  • The Astrophysical Journal, Vol. 644, Issue 1
  • DOI: 10.1086/503418

Bayesian Galaxy Shape Estimation
conference, November 2011

  • Bridle, S. L.; Kneib, J. -P.; Bardeau, S.
  • Proceedings of the Yale Cosmology Workshop, The Shapes of Galaxies and Their Dark Halos
  • DOI: 10.1142/9789812778017_0006

Detection of weak gravitational lensing by large-scale structure
journal, October 2000

  • Bacon, David J.; Refregier, Alexandre R.; Ellis, Richard S.
  • Monthly Notices of the Royal Astronomical Society, Vol. 318, Issue 2
  • DOI: 10.1046/j.1365-8711.2000.03851.x

The dark Energy Camera
journal, October 2015


Noise bias in weak lensing shape measurements: Noise bias in lensing shape measurement
journal, August 2012

  • Refregier, Alexandre; Kacprzak, Tomasz; Amara, Adam
  • Monthly Notices of the Royal Astronomical Society, Vol. 425, Issue 3
  • DOI: 10.1111/j.1365-2966.2012.21483.x

CFHTLenS: combined probe cosmological model comparison using 2D weak gravitational lensing
journal, February 2013

  • Kilbinger, Martin; Fu, Liping; Heymans, Catherine
  • Monthly Notices of the Royal Astronomical Society, Vol. 430, Issue 3
  • DOI: 10.1093/mnras/stt041

GREAT3 results – I. Systematic errors in shear estimation and the impact of real galaxy morphology
journal, May 2015

  • Mandelbaum, Rachel; Rowe, Barnaby; Armstrong, Robert
  • Monthly Notices of the Royal Astronomical Society, Vol. 450, Issue 3
  • DOI: 10.1093/mnras/stv781

The DES Science Verification weak lensing shear catalogues
journal, May 2016

  • Jarvis, M.; Sheldon, E.; Zuntz, J.
  • Monthly Notices of the Royal Astronomical Society, Vol. 460, Issue 2
  • DOI: 10.1093/mnras/stw990

Cosmology constraints from shear peak statistics in Dark Energy Survey Science Verification data
journal, August 2016

  • Kacprzak, T.; Kirk, D.; Friedrich, O.
  • Monthly Notices of the Royal Astronomical Society, Vol. 463, Issue 4
  • DOI: 10.1093/mnras/stw2070

Galaxy shear estimation from stacked images
journal, September 2009


Observational probes of cosmic acceleration
journal, September 2013


CFHTLenS tomographic weak lensing cosmological parameter constraints: Mitigating the impact of intrinsic galaxy alignments
journal, May 2013

  • Heymans, Catherine; Grocutt, Emma; Heavens, Alan
  • Monthly Notices of the Royal Astronomical Society, Vol. 432, Issue 3
  • DOI: 10.1093/mnras/stt601

A study of the sensitivity of shape measurements to the input parameters of weak-lensing image simulations
journal, March 2017

  • Hoekstra, Henk; Viola, Massimo; Herbonnet, Ricardo
  • Monthly Notices of the Royal Astronomical Society, Vol. 468, Issue 3
  • DOI: 10.1093/mnras/stx724

A demonstration of position angle-only weak lensing shear estimators on the GREAT3 simulations
journal, October 2015

  • Whittaker, Lee; Brown, Michael L.; Battye, Richard A.
  • Monthly Notices of the Royal Astronomical Society, Vol. 454, Issue 2
  • DOI: 10.1093/mnras/stv2085

Lensing bias in Cosmic Shear
journal, August 2009


Testing modified gravity with cosmic shear
journal, October 2015

  • Harnois-Déraps, J.; Munshi, D.; Valageas, P.
  • Monthly Notices of the Royal Astronomical Society, Vol. 454, Issue 3
  • DOI: 10.1093/mnras/stv2120

The effective number density of galaxies for weak lensing measurements in the LSST project
journal, July 2013

  • Chang, C.; Jarvis, M.; Jain, B.
  • Monthly Notices of the Royal Astronomical Society, Vol. 434, Issue 3
  • DOI: 10.1093/mnras/stt1156

Measurement and calibration of noise bias in weak lensing galaxy shape estimation
journal, December 2012


Bayesian lensing shear measurement
journal, January 2014

  • Bernstein, Gary M.; Armstrong, Robert
  • Monthly Notices of the Royal Astronomical Society, Vol. 438, Issue 2
  • DOI: 10.1093/mnras/stt2326

The Third Gravitational Lensing Accuracy Testing (Great3) Challenge Handbook
journal, April 2014

  • Mandelbaum, Rachel; Rowe, Barnaby; Bosch, James
  • The Astrophysical Journal Supplement Series, Vol. 212, Issue 1
  • DOI: 10.1088/0067-0049/212/1/5

The Canadian Cluster Comparison Project: detailed study of systematics and updated weak lensing masses★
journal, March 2015

  • Hoekstra, Henk; Herbonnet, Ricardo; Muzzin, Adam
  • Monthly Notices of the Royal Astronomical Society, Vol. 449, Issue 1
  • DOI: 10.1093/mnras/stv275

CFHTLenS: mapping the large-scale structure with gravitational lensing
journal, June 2013

  • Van Waerbeke, L.; Benjamin, J.; Erben, T.
  • Monthly Notices of the Royal Astronomical Society, Vol. 433, Issue 4
  • DOI: 10.1093/mnras/stt971

Detection of weak gravitational lensing distortions of distant galaxies by cosmic dark matter at large scales
journal, May 2000

  • Wittman, David M.; Tyson, J. Anthony; Kirkman, David
  • Nature, Vol. 405, Issue 6783
  • DOI: 10.1038/35012001

Sersic galaxy models in weak lensing shape measurement: model bias, noise bias and their interaction
journal, May 2014

  • Kacprzak, T.; Bridle, S.; Rowe, B.
  • Monthly Notices of the Royal Astronomical Society, Vol. 441, Issue 3
  • DOI: 10.1093/mnras/stu588

Intrinsic alignment-lensing interference as a contaminant of cosmic shear
journal, September 2004


The Shear Testing Programme – I. Weak lensing analysis of simulated ground-based observations
journal, April 2006

  • Heymans, Catherine; Van Waerbeke, Ludovic; Bacon, David
  • Monthly Notices of the Royal Astronomical Society, Vol. 368, Issue 3
  • DOI: 10.1111/j.1365-2966.2006.10198.x

First test of Verlinde's theory of emergent gravity using weak gravitational lensing measurements
journal, December 2016

  • Brouwer, Margot M.; Visser, Manus R.; Dvornik, Andrej
  • Monthly Notices of the Royal Astronomical Society, Vol. 466, Issue 3
  • DOI: 10.1093/mnras/stw3192

Shapes and Shears, Stars and Smears: Optimal Measurements for Weak Lensing
journal, February 2002

  • Bernstein, G. M.; Jarvis, M.
  • The Astronomical Journal, Vol. 123, Issue 2
  • DOI: 10.1086/338085

Shapelets -- II. A method for weak lensing measurements
journal, January 2003


im3shape: a maximum likelihood galaxy shear measurement code for cosmic gravitational lensing
journal, July 2013

  • Zuntz, Joe; Kacprzak, Tomasz; Voigt, Lisa
  • Monthly Notices of the Royal Astronomical Society, Vol. 434, Issue 2
  • DOI: 10.1093/mnras/stt1125

Galaxy–galaxy lensing in the Dark Energy Survey Science Verification data
journal, November 2016

  • Clampitt, J.; Sánchez, C.; Kwan, J.
  • Monthly Notices of the Royal Astronomical Society, Vol. 465, Issue 4
  • DOI: 10.1093/mnras/stw2988

The Cosmic Evolution Survey (COSMOS): Overview
journal, September 2007

  • Scoville, N.; Aussel, H.; Brusa, M.
  • The Astrophysical Journal Supplement Series, Vol. 172, Issue 1
  • DOI: 10.1086/516585

Cosmic shear analysis in 50 uncorrelated VLT fields. Implications for $\Omega_0$, $\sigma_8$
journal, March 2001


COSMOS: Three‐dimensional Weak Lensing and the Growth of Structure
journal, September 2007

  • Massey, Richard; Rhodes, Jason; Leauthaud, Alexie
  • The Astrophysical Journal Supplement Series, Vol. 172, Issue 1
  • DOI: 10.1086/516599

CFHTLenS: testing the laws of gravity with tomographic weak lensing and redshift-space distortions
journal, December 2012

  • Simpson, Fergus; Heymans, Catherine; Parkinson, David
  • Monthly Notices of the Royal Astronomical Society, Vol. 429, Issue 3
  • DOI: 10.1093/mnras/sts493

A Method for Weak Lensing Observations
journal, August 1995

  • Kaiser, Nick; Squires, Gordon; Broadhurst, Tom
  • The Astrophysical Journal, Vol. 449
  • DOI: 10.1086/176071

Bayesian galaxy shape measurement for weak lensing surveys – III. Application to the Canada–France–Hawaii Telescope Lensing Survey
journal, January 2013

  • Miller, L.; Heymans, C.; Kitching, T. D.
  • Monthly Notices of the Royal Astronomical Society, Vol. 429, Issue 4
  • DOI: 10.1093/mnras/sts454

Handbook for the GREAT08 Challenge: An image analysis competition for cosmological lensing
journal, March 2009

  • Bridle, Sarah; Shawe-Taylor, John; Amara, Adam
  • The Annals of Applied Statistics, Vol. 3, Issue 1
  • DOI: 10.1214/08-aoas222

KiDS-450: cosmological parameter constraints from tomographic weak gravitational lensing
journal, November 2016

  • Hildebrandt, H.; Viola, M.; Heymans, C.
  • Monthly Notices of the Royal Astronomical Society, Vol. 465, Issue 2
  • DOI: 10.1093/mnras/stw2805

Shear calibration biases in weak-lensing surveys
journal, August 2003


Shear nulling after PSF Gaussianisation: Moment-based weak lensing measurements with subpercent noise bias
journal, March 2017


Wide-Field Lensing Mass Maps from Dark Energy Survey Science Verification Data
journal, July 2015


The Shear Testing Programme 2: Factors affecting high-precision weak-lensing analyses
journal, March 2007


Handbook for the GREAT08 Challenge: An image analysis competition for cosmological lensing
journal, March 2009

  • Bridle, Sarah; Shawe-Taylor, John; Amara, Adam
  • The Annals of Applied Statistics, Vol. 3, Issue 1
  • DOI: 10.1214/08-AOAS222

Wide-Field Lensing Mass Maps from Dark Energy Survey Science Verification Data
journal, July 2015


Cosmology from cosmic shear with Dark Energy Survey Science Verification data
journal, July 2016


Intrinsic alignment-lensing interference as a contaminant of cosmic shear
journal, September 2004


Cosmic Shear Results from the deep lens Survey. ii. full Cosmological Parameter Constraints from Tomography
journal, June 2016


Lensing bias in Cosmic Shear
journal, August 2009


    Works referencing / citing this record:

    Density split statistics: Cosmological constraints from counts and lensing in cells in DES Y1 and SDSS data
    journal, July 2018


    Cosmological simulations for combined-probe analyses: covariance and neighbour-exclusion bias
    journal, August 2018

    • Harnois-Déraps, J.; Amon, A.; Choi, A.
    • Monthly Notices of the Royal Astronomical Society, Vol. 481, Issue 1
    • DOI: 10.1093/mnras/sty2319

    Dark Energy Survey year 1 results: Galaxy-galaxy lensing
    journal, August 2018


    Euclid preparation : IV. Impact of undetected galaxies on weak-lensing shear measurements⋆
    journal, July 2019


    Dark Energy Survey year 1 results: Cosmological constraints from galaxy clustering and weak lensing
    journal, August 2018


    Cosmic shear: Inference from forward models
    journal, July 2019


    Cosmological lensing ratios with DES Y1, SPT, and Planck
    journal, May 2019

    • Prat, J.; Baxter, E.; Shin, T.
    • Monthly Notices of the Royal Astronomical Society, Vol. 487, Issue 1
    • DOI: 10.1093/mnras/stz1309

    Dark Energy Survey Year 1 results: Cosmological constraints from cosmic shear
    journal, August 2018


    Weak lensing shear calibration with simulations of the HSC survey
    journal, September 2018

    • Mandelbaum, Rachel; Lanusse, François; Leauthaud, Alexie
    • Monthly Notices of the Royal Astronomical Society, Vol. 481, Issue 3
    • DOI: 10.1093/mnras/sty2420

    Towards emulating cosmic shear data: revisiting the calibration of the shear measurements for the Kilo-Degree Survey
    journal, April 2019


    Dark Energy Survey Year 1 results: weak lensing shape catalogues
    journal, August 2018

    • Zuntz, J.; Sheldon, E.; Samuroff, S.
    • Monthly Notices of the Royal Astronomical Society, Vol. 481, Issue 1
    • DOI: 10.1093/mnras/sty2219