Sliusar V. Microlensing of distant source in multibody gravitational lensing systems: statistics of light curves

We study gravitational microlensing of distant sources microlensed by a stochastic system of point masses-stars and extended clumps modeling dark matter subhalos. It is found that during high amplification events two groups of models of source brightness profiles can be distinguished: a) compact models (Gaussian, limb darkening); b) models with slowly decreasing brightness (power-law with low power index, Shakura-Sunyaev model). According to the results of statistical analysis the difference between light curves for source's models from different groups appears to reach 12%. It is shown that the impact of the binary systems in the lensing galaxy is neglectable. While changing the optical depth in the lensing galaxy the selected values of the optical depth are confirmed for some models of the source. The bimodal distributions of amplification coefficients are obtained for selected values of optical depth. According to suggested model of extended clumps of dark matter we obtain autocorrelation functions of light curves in case of different optical depths of the clumps. The impact of the clumps sizes and external shear is also studied. We found that the dependence of the autocorrelation functions upon the optical depth of the clumps is non-monotonous.