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arXiv · 2105.11471

The Prototype Telescope and Spectrograph System for the AMASE Project

Abstract

We present the design of the prototype telescope and spectrograph system for the Affordable Multiple Aperture Spectroscopy Explorer (AMASE) project. AMASE is a planned project that will pair 100 identical multi-fiber spectrographs with a large array of telephoto lenses to achieve a large area integral field spectroscopy survey of the sky at the spatial resolution of half an arcminute and a spectral resolution of R=15,000, covering important emission lines in the optical for studying the ionized gas in the Milky Way and beyond. The project will be enabled by a significant reduction in the cost of each spectrograph unit, which is achieved by reducing the beam width and the use of small-pixel CMOS detectors, 50um-core optical fibers, and commercial photographic lenses in the spectrograph. Although constrained by the challenging high spectral resolution requirement, we realize a 40% reduction in cost per fiber at constant etendue relative to, e.g., DESI. As the reduction of cost is much more significant than the reduction in the amount of light received per fiber, replicating such a system many times is more cost effective than building a single large spectrograph that achieves the same survey speed. We present the design of the prototype telescope and instrument system and the study of its cost effectiveness.

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Renbin Yan, Matthew A. Bershady, Michael P. Smith, Nicholas MacDonald, Dmitry Bizyaev, Kevin Bundy, Sabyasachi Chattopadhyay, James E. Gunn, Kyle B. Westfall, Marsha J. Wolf. 2021-05-24. The Prototype Telescope and Spectrograph System for the AMASE Project. https://doi.org/10.1117/12.2563195

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