Inference from the small scales of cosmic shear with current and future Dark Energy Survey data

Research output: Contribution to journalArticle

  • Authors:
  • Niall Maccrann
  • J Aleksic
  • A Amara
  • Sarah Bridle
  • C. Bruderer
  • And 59 others
  • External authors:
  • C. Chang
  • Scott Dodelson
  • T. Eifler
  • M. E. Huffer
  • D. Huterer
  • T. Kacprzak
  • A Refregier
  • E {Suchyta}
  • R H Wechsler
  • Joseph Zuntz
  • T. M C Abbott
  • S {Allam}
  • J {Annis}
  • R Armstrong
  • A Benoit-Levy
  • D. Brooks
  • D. L. Burke
  • A. Carnero Rosell
  • Carrasco Kind
  • J {Carretero}
  • F J {Castander}
  • M {Crocce}
  • C E {Cunha}
  • L N {da Costa}
  • S Desai
  • H. T. Diehl
  • J. Dietrich
  • P {Doel}
  • A E {Evrard}
  • B. Flaugher
  • P. Fosalba
  • D W {Gerdes}
  • D. A. Goldstein
  • D {Gruen}
  • Robert A. Gruendl
  • G. Gutierrez
  • K. Honscheid
  • D. J. James
  • M Jarvis
  • E {Krause}
  • K {Kuehn}
  • N {Kuropatkin}
  • M {Lima}
  • J. L. Marshall
  • P. Melchior
  • F. Menanteau
  • R. Miquel
  • A A {Plazas}
  • A K Romer
  • E S Rykoff
  • E. Sanchez
  • V {Scarpine}
  • I {Sevilla-Noarbe}
  • E. Sheldon
  • M {Soares-Santos}
  • M E C {Swanson}
  • G {Tarle}
  • D. Thomas
  • V {Vikram}


Cosmic shear is sensitive to fluctuations in the cosmological matter density eld, including on small physical scales, where matter clustering is affected by baryonic physics in galaxies and galaxy clusters, such as star formation, supernovae feedback and AGN feedback. While muddying any cosmological information that is contained in small scale cosmic shear measurements, this does mean that cosmic shear has the potential to constrain baryonic physics and galaxy formation. We perform an analysis of the Dark Energy Survey (DES) Science Verication (SV) cosmic shear measurements, now extended to smaller scales, and using the Mead et al. (2015) halo model to account for baryonic feedback.While the SV data has limited statistical power, we demonstrate using a simulated likelihood analysis that the nal DES data will have the statistical power to didifferentiate among baryonic feedback scenarios. We also explore some of the difficulties in interpreting the small scales in cosmic shear measurements, presenting
estimates of the size of several other systematic eects that make inference from small
scales dicult, including uncertainty in the modelling of intrinsic alignment on nonlin-
ear scales, `lensing bias', and shape measurement selection eects. For the latter two,
we make use of novel image simulations. While future cosmic shear datasets have the
statistical power to constrain baryonic feedback scenarios, there are several systematic
eects that require improved treatments, in order to make robust conclusions about
baryonic feedback.

Bibliographical metadata

Original languageEnglish
JournalMonthly Notices of the Royal Astronomical Society
Early online dateNov 2016
StatePublished - Mar 2017