Simulating diffractions and chromatic effects in the microlens array in searching for extrasolar planets with SPHERE IFS

摘要

Observations of extrasolar planets using Integral Field Spectroscopy (IFS), if coupled with an extreme Adaptive Optics system and analyzed with a Simultaneous Differential Imaging technique (SDI), are a powerful tool to detect and characterize extrasolar planets directly; they enhance the signal of the planet and, at the same time, reduces the impact of stellar light and consequently important noise sources like speckles. We developed a simulation code able to test the capabilities of this IFS-SDI technique for different kinds of planets and telescopes, modeling the atmospheric and instrumental noise sources, and the main results of this code have been presented in Ref.1. This code, although it takes into account many parameters and sources of noise, can still be improved, and in order to do it we studied in detail two aspects that have been neglected in the first version of the code: the not uniform illumination of the microlenses and the speckle undersampling. The results of these studies are presented here.