Asymmetry in Microlensing-Induced Light Curves

Abstract

We discuss distortion in microlensing-induced light curves which are considered to be curves due to single-point-mass lenses at a first glance. As factors of the distortion, we consider close binary and planetary systems, which are the limiting cases of two-point-mass lenses, and the gravitational potential is regarded as the sum of the single point mass and the corrections. In order to quantitatively estimate the asymmetric features of such distorted light curves, we propose a cutoff dependent skewness, and show how to discriminate the similar light curves with it. We also examine as the distortion the general relativistic effect of frame dragging, but the effect coincides with the close binary case in the light curves.Comment: 18 pages, 17 eps figures, Accepted for publication in Prog. Theor. Phy