RSAA Colloquia / Seminars / Feast-of-Facts: Friday, 03 July 2015, 14:00-14:20; Duffield Lecture Theatre

Michael Ireland

"The Adaptive Optics Upgrade for the CHARA Array"

The CHARA array at Mt Wilson, California, is the world’s highest angular resolution instrument, able to image the surface of stars and measure angular diameters down to about 200 micro-arcseconds. With six simultaneous telescopes, ~300 optical elements, dozens of active servo loops and ~500 actuators, the system is already arguably the most complex optical or infrared telescope system in the world. It is capable of full remote operation, and runs with a staff of approximately 10 people and a publication rate of approximately 14 papers/year (including several in Science and Nature). Despite the success of CHARA, the future of the facility depends critically on improved sensitivity and precision. I will describe the adaptive optics upgrade currently underway, which includes a feed forward component where the wavefront sensor is located 200m upstream of the deformable mirror in the optical train. I will conclude with the kinds of science that these upgrades will enable, focusing on young stars and exoplanets.