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arXiv · astro-ph/0104244

Lensing magnification effects on the cosmic shear statistics

Takashi Hamana
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Abstract

Gravitational lensing causes a correlation between a population of foreground large-scale structures and the observed number density of the background distant galaxies as a consequence of the flux magnification and the lensing area distortion. This correlation has not been taken into account in calculations of the theoretical predictions of the cosmic shear statistics but may cause a systematic error in a cosmic shear measurement. We examine its impact on the cosmic shear statistics using the semi-analytic approach. We find that the lensing magnification has no practical influence on the cosmic shear variance. Exploring possible shapes of redshift distribution of source galaxies, we find that the relative amplitude of the effect on the convergence skewness is 3% at most

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Takashi Hamana. 2001-05-28. Lensing magnification effects on the cosmic shear statistics. https://doi.org/10.1046/j.1365-8711.2001.04607.x

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