Mechanical design for the PRAXIS spectrograph

The primary aim of PRAXIS is to determine the full astronomical potential of the technique of using fibre Bragg gratings (FBGs) for atmospheric OH suppression in astronomy. To achieve this, we are now building, in a close collaboration with the University of Sydney and the Astrophysical Institute Potsdam, a dedicated high-throughput low-noise J and H-band spectrograph and associated fibre feed and telescope fore-optics unit.

For atmospheric line filtering, the instrument will employ the GNOSIS FBG fibre bundle and a new multicore FBG bundle now being developed. The intention is to test the instrument at the AAT in the first half of 2015, before moving to a high altitude telescope later in the year.