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arXiv · 2002.04542

Full-Array Noise Performance of Deployment-Grade SuperSpec mm-wave On-Chip Spectrometers

K. S. Karkare·P. S. Barry·C. M. Bradford·S. Chapman·S. Doyle·J. Glenn·S. Gordon·S. Hailey-Dunsheath·R. M. J. Janssen·A. Kovacs·H. G. LeDuc·P. Mauskopf·R. McGeehan·J. Redford·E. Shirokoff·C. Tucker·J. Wheeler·J. Zmuidzinas
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Abstract

SuperSpec is an on-chip filter-bank spectrometer designed for wideband moderate-resolution spectroscopy at millimeter wavelengths, employing TiN kinetic inductance detectors. SuperSpec technology will enable large-format spectroscopic integral field units suitable for high-redshift line intensity mapping and multi-object spectrographs. In previous results we have demonstrated noise performance in individual detectors suitable for photon noise limited ground-based observations at excellent mm-wave sites. In these proceedings we present the noise performance of a full $R\sim 275$ spectrometer measured using deployment-ready RF hardware and software. We report typical noise equivalent powers through the full device of $\sim 3 \times 10^{-16} \ \mathrm{W}/\sqrt{\mathrm{Hz}}$ at expected sky loadings, which are photon noise dominated. Based on these results, we plan to deploy a six-spectrometer demonstration instrument to the Large Millimeter Telescope in early 2020.

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K. S. Karkare, P. S. Barry, C. M. Bradford, S. Chapman, S. Doyle, J. Glenn, S. Gordon, S. Hailey-Dunsheath, R. M. J. Janssen, A. Kovacs, H. G. LeDuc, P. Mauskopf, R. McGeehan, J. Redford, E. Shirokoff, C. Tucker, J. Wheeler, J. Zmuidzinas. 2020-02-11. Full-Array Noise Performance of Deployment-Grade SuperSpec mm-wave On-Chip Spectrometers. https://doi.org/10.1007/s10909-020-02407-4

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