Detecting Jupiters with AMBER on the VLTI

Since several years, long baseline infrared interferometry succeeds in providing handful of astrophysical results from model fitting of the visibility measurements alone. Continuing on these encouraging results, and thanks to the development of elaborated recombination scheme which allow to gather stellar light coming from 3 telescopes or more, recent (IOTA/IONIC, NPOI) and new (V-LTI/AMBER) interferometers have also access to closure phase measurements as well as to a better (u,v) coverage. When the (u,v) coverage is still insufficient to perform image reconstruction. a least square fit approach is required, taking benefit of the closure phases together with visibility informations. Within this framework, and in the light of the AMBER experiment, we simulate realistic observations of star-planet systems. Computing the statistics of the observables, and then characterizing the performances of this instrument, we investigate the potential of AMBER to detect Jovian planets around sun-like stars by computing Signal to Noise Ratio on the constrained parameters, i.e. the flux ratio and the separation. We focus here on the specific system sun-planet, knowing that the general case will be treated in a forthcoming paper. We particularly study how important is the contribution of the closure phase in the model-fitting process, relatively to the visibility.