GRAVITATIONAL LENSING BY LARGE-SCALE STRUCTURES

The statistical gravitational lensing effects on supercluster scales are investigated. We follow closely the study of Jaroszynski et al. (1990, hereafter JPPG), but we introduce a completely different, semi-analytical description of the (dark) matter distribution and account explicitly for the correlation between convergence and shear, which is neglected in their paper. We find that gravitational lensing due to large-scale inhomogeneities is fairly weak and does, by itself, not affect the image properties of distant sources significantly. Our results are in remarkable agreement with those of JPPG, showing that our model for the large-scale structure is as appropriate as their much more elaborate one for the present purposes, and that the correlation between convergence and shear has no preceptible influence.