KiDS-i-800: comparing weak gravitational lensing measurements from same-sky surveys. Issue 4 (5th April 2018)

• Record Type: Journal Article
• Authors: Amon, A; Heymans, C; Klaes, D; Erben, T; Blake, C; Hildebrandt, H; Hoekstra, H; Kuijken, K; Miller, L; Morrison, C B; Choi, A; de Jong, J T A; Glazebrook, K; Irisarri, N; Joachimi, B; Joudaki, S; Kannawadi, A; Lidman, C; Napolitano, N; Parkinson, D; Schneider, P; van Uitert, E; Viola, M; Wolf, C
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 477:Issue 4(2018)
• Page Start: 4285
• Page End: 4307
• Publication Date: 2018-04-05
• Subjects: gravitational lensing: weak -- surveys -- galaxies: photometry -- cosmology: observations; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/sty859
• Languages: English
• ISSNs: 0035-8711

Abstract

Abstract: We present a weak gravitational lensing analysis of 815 deg 2 of i -band imaging from the Kilo-Degree Survey (KiDS- i -800). In contrast to the deep r -band observations, which take priority during excellent seeing conditions and form the primary KiDS data set (KiDS‐ r ‐450), the complementary yet shallower KiDS- i -800 spans a wide range of observing conditions. The overlapping KiDS- i -800 and KiDS‐ r ‐450 imaging therefore provides a unique opportunity to assess the robustness of weak lensing measurements. In our analysis we introduce two new 'null' tests. The 'nulled' two-point shear correlation function uses a matched catalogue to show that the calibrated KiDS- i -800 and KiDS‐ r ‐450 shear measurements agree at the level of 1 ± 4 per cent. We use five galaxy lens samples to determine a 'nulled' galaxy–galaxy lensing signal from the full KiDS- i -800 and KiDS‐ r ‐450 surveys and find that the measurements agree to 7 ± 5 per cent when the KiDS- i -800 source redshift distribution is calibrated using either spectroscopic redshifts, or the 30-band photometric redshifts from the COSMOS survey.