Performance of Echidna fiber positioner for FMOS on Subaru

摘要

Echidna is a fiber positioner designed and built by the Anglo-Australian Observatory using novel technology to position 400 fibers in the prime focus field of the Subaru telescope. The fibers feed two near infrared OH-suppression spectrographs, the whole project being known as Fiber Multi Object Spectrograph (FMOS). In order to accommodate the large number of the fibers in the physically limited area, a new fiber positioning method is developed. Stand-alone tests of the positioner at sea level confirm its performance is fully satisfactory. Initial results and prospects of the on-sky commissioning tests of the positioner are also described.