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arXiv · 1608.04110

Design and modeling of a moderate-resolution astronomic spectrograph with volume-phase holographic gratings

Eduard R. Muslimov·Gennady G. Valyavin·Sergey N. Fabrika·Nadezhda K. Pavlycheva
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Abstract

We present an optical design of astronomic spectrograph based on a cascade of volume-phase holographic gratings. The cascade consists of three gratings. Each of them provides moderately high spectral resolution in a narrow range of 83 nm. Thus the spectrum image represents three lines covering region 430-680 nm. Two versions of the scheme are described: a full-scale one with estimated resolving power of 5300-7900 and a small-sized one intended for creation of a lab prototype, which provides the resolving power of 1500-3000. Diffraction efficiency modeling confirms that the system throughput can reach 75 %, while stray light caused by the gratings crosstalk is negligible. We also propose a design of image slicer and focal reducer allowing to couple the instrument with the 6-m telescope. Finally, we present concept of the opto-mechanical design.

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Eduard R. Muslimov, Gennady G. Valyavin, Sergey N. Fabrika, Nadezhda K. Pavlycheva. 2016-08-14. Design and modeling of a moderate-resolution astronomic spectrograph with volume-phase holographic gratings. https://doi.org/10.1117/12.2231985

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