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arXiv · 1911.11687

The Design of The CCAT-prime Epoch of Reionization Spectrometer Instrument

Nicholas F Cothard·Steve K Choi·Cody J Duell·Terry Herter·Johannes Hubmayr·Jeff McMahon·Michael D Niemack·Thomas Nikola·Carlos Sierra·Gordon J Stacey·Eve M Vavagiakis·Edward J Wollack·Bugao Zou
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Abstract

The Epoch of Reionization Spectrometer (EoR-Spec) is an instrument module for the Prime-Cam receiver of the 6 m aperture CCAT-prime Telescope at 5600 m in Chile. EoR-Spec will perform 158 $μ$m [CII] line intensity mapping of star-forming regions at redshifts between 3.5 and 8 (420 - 210 GHz), tracing the evolution of structure during early galaxy formation. At lower redshifts, EoR-Spec will observe galaxies near the period of peak star formation - when most stars in today's universe were formed. At higher redshifts, EoR-Spec will trace the late stages of reionization, the early stages of galaxy assembly, and the formation of large-scale, three-dimensional clustering of star-forming galaxies. To achieve its science goals, EoR-Spec will utilize CCAT-prime's exceptionally low water vapor site, large field of view ($\sim 5$ degrees at 210 GHz), and narrow beam widths ($\sim 1$ arcminute at 210 GHz). EoR-Spec will be outfitted with a cryogenic, metamaterial, silicon substrate-based Fabry-Perot Interferometer operating at a resolving power ($λ/Δλ$) of 100. Monolithic dichroic arrays of cryogenic, feedhorn-coupled transition edge sensor bolometers provide approximately 6000 detectors, which are read out using a frequency division multiplexing system based on microwave SQUIDs. The novel design allows the measurement of the [CII] line at two redshifts simultaneously using dichroic pixels and two orders of the Fabry-Perot. Here we present the design and science goals of EoR-Spec, with emphasis on the spectrometer, detector array, and readout designs.

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Nicholas F Cothard, Steve K Choi, Cody J Duell, Terry Herter, Johannes Hubmayr, Jeff McMahon, Michael D Niemack, Thomas Nikola, Carlos Sierra, Gordon J Stacey, Eve M Vavagiakis, Edward J Wollack, Bugao Zou. 2019-11-26. The Design of The CCAT-prime Epoch of Reionization Spectrometer Instrument. https://doi.org/10.1007/s10909-019-02297-1

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