Illuminating hot Jupiters in caustic crossing

Abstract

In recent years a large number of hot Jupiters orbiting in a very close orbit around the parent stars have been explored with the transit and Doppler effect methods. Here in this paper we study the gravitational microlensing effect of a binary lens on a parent star with a hot Jupiter revolving around it. Caustic crossing of the planet makes enhancements on the light curve of the parent star in which the signature of the planet can be detected by high-precision photometric observations. We use the inverse ray shooting method with tree code algorithm to generate the combined light curve of the parent star and the planet. In order to investigate the probability of observing the planet signal, we do a Monte Carlo simulation and obtain the observational optical depth of τ∼ 10-8. We show that about 10 yr of observations of Galactic bulge with a network of telescopes will enable us detecting about 10 hot Jupiters with this method. Finally we show that the observation of the microlensing event in the infrared band will increase the probability for detection of the exoplanets. © 2010 The Authors. Journal compilation © 2010 RAS.