im3shape: a maximum likelihood galaxy shear measurement code for cosmic gravitational lensing [PDF]
Monthly Notices of the Royal Astronomical Society, 2013 We present and describe im3shape, a new publicly available galaxy shape measurement code for weak gravitational lensing shear. im3shape performs a maximum likelihood fit of a bulge-plus-disc galaxy model to noisy images, incorporating an applied point spread function.
J. Zuntz +5 more
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Weak gravitational lensing shear measurement with FPFS: analytical mitigation of noise bias and selection bias [PDF]
Monthly Notices of the Royal Astronomical Society, 2022 ABSTRACT Dedicated ‘Stage IV’ observatories will soon observe the entire extragalactic sky, to measure the ‘cosmic shear’ distortion of galaxy shapes by weak gravitational lensing. To measure the apparent shapes of those galaxies, we present an improved version of the Fourier Power Function Shapelets (FPFS) shear measurement method. This
Xiangchong Li, Yin Li, Richard Massey
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Weak gravitational lensing in different cosmologies, using an algorithm for shear in three dimensions [PDF]
Monthly Notices of the Royal Astronomical Society, 2002 We present the results of weak gravitational lensing statistics in four different cosmological $N$-body simulations. The data has been generated using an algorithm for the three-dimensional shear, which makes use of a variable softening facility for the $N$-body particle masses, and enables a physical interpretation for the large-scale structure to be ...
Andrew J. Barber +3 more
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Strong gravitational lensing’s ‘external shear’ is not shear [PDF]
Monthly Notices of the Royal Astronomical SocietyABSTRACT The distribution of mass in galaxy-scale strong gravitational lenses is often modelled as an elliptical power-law plus ‘external shear’, which notionally accounts for neighbouring galaxies and cosmic shear along our line of sight.
Amy Etherington +22 more
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Simulations of weak gravitational lensing – II. Including finite support effects in cosmic shear covariance matrices [PDF]
Monthly Notices of the Royal Astronomical Society, 2015 (Abridged) We investigate and quantify the impact of finite simulation volume on weak lensing two- and four-point statistics. These {\it finite support} (FS) effects are modelled for several estimators, simulation box sizes and source redshifts, and validated against a new large suite of 500 $N$-body simulations.
Harnois-Déraps, J, van Waerbeke, L
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A NEW METHOD FOR MEASURING WEAK GRAVITATIONAL LENSING SHEAR USING HIGHER ORDER SPIN-2 HOLICs [PDF]
The Astrophysical Journal, 2009 Accepted for publication in ApJ; 10 pages, 7 figures, uses aastex ...
Okura, Yuki, Futamase, Toshifumi
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Monthly Notices of the Royal Astronomical Society, 2022 ABSTRACT We investigate the performance of the metacalibration shear calibration framework using simulated imaging data for the Nancy Grace Roman Space Telescope (Roman) reference High-Latitude Imaging Survey (HLIS). The weak lensing programme of Roman requires the mean weak lensing shear estimate to be calibrated within about 0.03 per ...
Masaya Yamamoto +7 more
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Shear and magnification angular power spectra and higher-order moments from weak gravitational lensing [PDF]
Monthly Notices of the Royal Astronomical Society, 2003 Revised in accordance with referee's report; now accepted by ...
Barber, Andrew J., Taylor, A. N.
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Gravitational lensing shear by an exotic lens object with negative convergence or negative mass [PDF]
Physical Review D, 2013 Gravitational lens models with negative convergence(surface mass density projected onto the lens plane) inspired by modified gravity theories, exotic matter and energy have been recently discussed in such a way that a static and spherically-symmetric modified spacetime metric depends on the inverse distance to the power of positive $n$(n=1 for ...
Izumi, Koji +4 more
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Measuring the three-dimensional shear from simulation data, with applications to weak gravitational lensing [PDF]
Monthly Notices of the Royal Astronomical Society, 1999 22 pages, latex, 11 ...
Couchman, H. M. P. +2 more
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