A nonsingular model for a gravitational microlens

The microlensing of distant stars by noncompact objects, such as neutralino stars, is considered. The mass density distribution in the microlens is as sumed to have no singularity at the coordinate origin (like the mass distri bution in a nonsingular isothermal sphere, or in an isothermal sphere with a core). A detailed analysis of the gravitational-lens equation is presente d, its analytical solutions are obtained, and an expression for amplificati on by the gravitational lens is derived. It is shown that microlensing even ts with two characteristic maxima in their light curves, which are usually accounted for by the action of a double compact microlens, can be explained by the proposed model.