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arXiv · 1608.01196

Visible camera cryostat design and performance for the SuMIRe Prime Focus Spectrograph (PFS)

Stephen A. Smee·James E. Gunn·Mirek Golebiowski·Stephen C. Hope·Fabrice Madec·Jean-Francois Gabriel·Craig Loomis·Arnaud Le Fur·Kjetil Dohlen·David Le Mignant·Robert Barkhouser·Michael Carr·Murdock Hart·Naoyuki Tamura·Atsushi Shimono·Naruhisa Takato
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Abstract

We describe the design and performance of the SuMIRe Prime Focus Spectrograph (PFS) visible camera cryostats. SuMIRe PFS is a massively multi-plexed ground-based spectrograph consisting of four identical spectrograph modules, each receiving roughly 600 fibers from a 2394 fiber robotic positioner at the prime focus. Each spectrograph module has three channels covering wavelength ranges 380~nm -- 640~nm, 640~nm -- 955~nm, and 955~nm -- 1.26~um, with the dispersed light being imaged in each channel by a f/1.07 vacuum Schmidt camera. The cameras are very large, having a clear aperture of 300~mm at the entrance window, and a mass of $\sim$280~kg. In this paper we describe the design of the visible camera cryostats and discuss various aspects of cryostat performance.

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Stephen A. Smee, James E. Gunn, Mirek Golebiowski, Stephen C. Hope, Fabrice Madec, Jean-Francois Gabriel, Craig Loomis, Arnaud Le Fur, Kjetil Dohlen, David Le Mignant, Robert Barkhouser, Michael Carr, Murdock Hart, Naoyuki Tamura, Atsushi Shimono, Naruhisa Takato. 2016-08-03. Visible camera cryostat design and performance for the SuMIRe Prime Focus Spectrograph (PFS). https://doi.org/10.1117/12.2233185

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