Direct shear mapping – a new weak lensing tool
نویسندگان
چکیده
منابع مشابه
A New Shear Estimator for Weak Lensing Observations
We present a new shear estimator for weak lensing observations which properly accounts for the effects of a realistic point spread function (PSF). Images of faint galaxies are subject to gravitational shearing followed by smearing with the instrumental and/or atmospheric PSF. We construct a ‘finite resolution shear operator’ which when applied to an observed image has the same effect as a gravi...
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We study a possibility to use the octopole moment of gravitationally lensed images as a direct measure of the third-order weak gravitational lensing effect, or the gravitational flexion. It turns out that there is a natural relation between flexion and certain combinations of octopole/higher-multipole moments which we call the Higher Order Lensing Image’s Characteristics (HOLICs). This will all...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2015
ISSN: 1365-2966,0035-8711
DOI: 10.1093/mnras/stv1083