Back to Search Start Over

KiDS-450: enhancing cosmic shear with clipping transformations.

Authors :
Giblin, Benjamin
Heymans, Catherine
Harnois-Déraps, Joachim
Simpson, Fergus
Dietrich, Jörg P
Van Waerbeke, Ludovic
Amon, Alexandra
Asgari, Marika
Erben, Thomas
Hildebrandt, Hendrik
Source :
Monthly Notices of the Royal Astronomical Society; Nov2018, Vol. 480 Issue 4, p5529-5549, 21p
Publication Year :
2018

Abstract

We present the first 'clipped' cosmic shear measurement using data from the Kilo-Degree Survey (KiDS-450). 'Clipping' transformations suppress the signal from the highest density, non-linear regions of cosmological fields. We demonstrate that these transformations improve constraints on S <subscript>8</subscript> = σ<subscript>8</subscript>(Ω<subscript>m</subscript>/0.3)<superscript>0.5</superscript> when used in combination with conventional two-point statistics. For the KiDS-450 data, we find that the combined measurements improve the constraints on S <subscript>8</subscript> by 17 per cent, compared to shear correlation functions alone. We determine the expectation value of the clipped shear correlation function using a suite of numerical simulations, and develop methodology to mitigate the impact of masking and shot noise. Future improvements in numerical simulations and mass reconstruction methodology will permit the precise calibration of clipped cosmic shear statistics such that clipping can become a standard tool in weak-lensing analyses. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
00358711
Volume :
480
Issue :
4
Database :
Complementary Index
Journal :
Monthly Notices of the Royal Astronomical Society
Publication Type :
Academic Journal
Accession number :
132718419
Full Text :
https://doi.org/10.1093/mnras/sty2271