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An international team led by The University of Texas and Pennsylvania State University is planning a fiber fed highresolution spectrograph for the Spectroscopic Survey Telescope. Design goals are (1) resolution 60,000 with a fiberdiameter greater than 1 arc second, (2) spectral coverage per exposure to the limits permitted by the combined bandpass of the SST and optical fibers and the RQE and area of the CCD. The R • product will be maximized by use of a high-blaze angle echelle mosaic and image or pupil slicing while the bandwidth will be maximized usingcross dispersion and dichroic beam division in a dual spectrograph with large-area CCDs. Critical issues are crossdispersion and order spacing, sky subtraction, echelle and CCD selection, fiber optic feed, and image or pupil slicing.Proposed methods to achieve the goals and meet the challenges posed by the issues will be presented. 1. INTRODUCTION The Spectroscopic Survey Telescope (SST) has been described elsewhere.1'2'3 It will be an Arecibo-type opticaltelescope with axis of its 1O-m segmented spherical mirror tilted 35 from the zenith, its pointing direction fixedduring observations. Objects will be followed across the curved focal surface by a six-axis tracker carrying the primefocus corrector, field acquisition camera, faint object spectrograph, and optical fiber feeds. The 12 square tracker |
