Statistics of light curves of a distant source microlensed by a system of point and extended masses

1Sliusar, VM, 1Zhdanov, VI, 1Alexandrov, AN, 1Fedorova, EV
1Astronomical Observatory of Taras Shevchenko National University of Kyiv, Kyiv, Ukraine
Kinemat. fiz. nebesnyh tel (Online) 2015, 31(2):47-58
Start Page: Extragalactic Astronomy
Language: Russian

We study the gravitational microlensing of a distant source microlensed by a stochastic system of point masses-stars and extended clumps modeling dark matter subhalos. The size of each clump is assumed to be 5 or 10 Einstein radii according to its mass. For each set of initial parameters (optical depth of microlensing, size of the clump) we generated 100 realizations of magnification patterns considering spatially homogeneous distribution of microlenses with the Salpeter mass function. On the basis of this we calculated autocorrelation functions of light curves for different relative contributions of clumps with total optical depth σtot = 0.3. It is found that the dependence of the autocorrelation functions upon the optical depth of the clumps is non-monotonous.

Keywords: gravitational microlensing, point-of-star point system

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