Review of small-angle coronagraphic techniques in the wake of ground-based second-generation adaptive optics systems

Abstract

Small-angle coronagraphy is technically and scientifically appealing because it enables the use of smaller tele-scopes, allows covering wider wavelength ranges, and potentially increases the yield and completeness of circum-stellar environment – exoplanets and disks – detection and characterization campaigns. However, opening up this new parameter space is challenging. Here we will review the four posts of high contrast imaging and their intricate interactions at very small angles (within the first 4 resolution elements from the star). The four posts