Narrow Results

Timing analysis is a powerful tool used to determine periodic features of physical phenomena. Here we review two applications of timing analysis to gravitational microlensing events. The first one, in particular cases, allows the estimation of the orbital period of binary lenses, which in turn enables the breaking of degeneracies. The second one is a method to measure the rotation period of the lensed star by observing signatures due to stellar spots on its surface.

It is known that small-scale structures in the transit light curves of exoplanets can be used to infer the sizes and temperatures of dark spots or bright faculae of their host stars. Among many factors, the precision depends on the observational statistics, the ratio of the size of the exoplanet to that of the dark (or bright) spot and the cadence used in the light curve measurements. We have developed a numerical code allowing us to explore the effects and limitations of such a method for stars of different spectral types.