L2 Point vs. Geosynchronous Orbit for Parallax Effect by Simulations

The isolated dark low-mass objects in our Galaxy, such as free-floating planets (FFP), can be detected by microlensing observations. By the light curve can be defined three parameters, but only the Einstein time, TE involves the mass, the distance and the transverse velocity of the lens. To break this degeneracy, have to be detected the perturbations in the light curve due to the relative accelerations among the observer, the lens and the source. Recently, toward Galactic bulge are planned space-based microlensing observations by WFIRST, which can be located in L2 point or geosynchronous orbit (GSO). Using the simulations Monte Carlo in C++ we investigate that the better position for the parallax effect detection in microlensing events caused by FFPs is L2 point than GSO.