High performance coronagraphy for direct imaging of exoplanets

¹ Subaru Telescope, National Astronomical Observatory of Japan, 640 N. A’ohoku Pl., Hilo, HI 96720, USA
² Steward Observatory, University of Arizona, 933 N. Cherry Ave., Tucson, AZ 85721, USA

Abstract

Coronagraphy has recently been an extremely active field of research, with several high performance concepts proposed, and several new coronagraphs tested in laboratories and telescopes. Coronagraph concepts can be grouped in a few broad categories: Lyot-type coronagraphs, pupil apodization and nulling interferometers. Among existing coronagraph concepts, several approach the fundamental performance limit imposed by the physical nature of light. To achieve their full potential, coronagraphs require exquisite wavefront control and calibration. This has been, and still is, the main bottleneck for the scientifically productive use of coronagraphs on ground-based telescopes. New and promising wavefront sensing techniques suitable for high contrast imaging have however been developed in the last few years and are started to be realized in laboratories. I will review some of these enabling technologies, and show that coronagraphs are now ready for “prime time” on existing and future telescopes.