par- 19 février 2008
MUSE (Multi Unit Spectroscopic Explorer) is a second generation integral field spectrograph proposed to the European Southern Observatory (ESO) for the VLT. MUSE combines a 1’ x 1’ Field of View (FoV) with a spectral resolution going to 3000 and a spatial resolution of 0.2” provided by the GALACSI adaptive optics system. MUSE is operating in the visible and near IR wavelength range (0.465-0.93 ìm). It is composed of 24 identical integral field units ; each one incorporates an advanced image slicer made of a combination of mirrors and mini-lenses arrays. During the feasibility study, a slicer prototype has been designed, manufactured and tested. This paper firstly describes an original approach for the slicer optical design and manufacturing. Then, we will focus on the optical tests of the prototype. These tests included the control of the angular tilts and assembling method of the slicer, the measurements of the position, size and shape of the pseudo-slits, the measurements of the Point Spread Function (PSF) for the slice-slit imagery on the whole FoV and an estimation of the size of the global exit pupil. We finally conclude on the feasibility of MUSE image slicer and its possible improvement for the next design phase.
Keywords : Integral Field Unit, Integral Field Spectroscopy, Advanced Image Slicer, MUSE instrument, VLT instrumentation.