Restoration of interferometric images - II. The case-study of the Large Binocular Telescope

We present in this paper a study of the imaging properties of the Large Binocular Telescope interferometer, focusing our attention on what we believe to be the most relevant effects, namely the limited angular coverage and the partial adaptive optics (AO) correction. For this purpose we make use of the Software Package AIRY (Astronomical Image Restoration in interferometrY), designed for multiple deconvolution of interferometric images and presented in our previous paper. We also consider as our testing object a model of young binary star consisting of a core binary surrounded by a massive circumbinary ring seen in scattered light, similar to that of GGTau. The effect of angular coverage, linked to the problem of time-averaging smearing of the interferometric images, is investigated for a number of cases corresponding to different declinations of the observed object. We find encouraging results showing that a good estimation of the relevant astronomical parameters of the object can be obtained even with an incomplete angular coverage. We then study the effect of partial AO-correction for both schemes of classical AO and multi-conjugate AO. We show that uniformity of the point-spread function over the field-of-view, rather than absolute global quality, is fundamental for the quality of the restored image.