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arXiv · 2111.04631

SPT-SLIM: A Line Intensity Mapping Pathfinder for the South Pole Telescope

K. S. Karkare·A. J. Anderson·P. S. Barry·B. A. Benson·J. E. Carlstrom·T. Cecil·C. L. Chang·M. A. Dobbs·M. Hollister·G. K. Keating·D. P. Marrone·J. McMahon·J. Montgomery·Z. Pan·G. Robson·M. Rouble·E. Shirokoff·G. Smecher
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Abstract

The South Pole Telescope Summertime Line Intensity Mapper (SPT-SLIM) is a pathfinder experiment that will demonstrate the use of on-chip filter-bank spectrometers for mm-wave line intensity mapping (LIM). The SPT-SLIM focal plane consists of 18 dual-polarization R=300 filter-bank spectrometers covering 120-180 GHz, coupled to aluminum kinetic inductance detectors. A compact cryostat holds the detectors at 100 mK and performs observations without removing the SPT-3G receiver. SPT-SLIM will be deployed to the 10-m South Pole Telescope for observations during the 2023-24 austral summer. We discuss the overall instrument design, expected detector performance and sensitivity to the LIM signal from CO at 0.5 < z < 2. The technology and observational techniques demonstrated by SPT-SLIM will enable next-generation LIM experiments that constrain cosmology beyond the redshift reach of galaxy surveys.

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K. S. Karkare, A. J. Anderson, P. S. Barry, B. A. Benson, J. E. Carlstrom, T. Cecil, C. L. Chang, M. A. Dobbs, M. Hollister, G. K. Keating, D. P. Marrone, J. McMahon, J. Montgomery, Z. Pan, G. Robson, M. Rouble, E. Shirokoff, G. Smecher. 2021-11-08. SPT-SLIM: A Line Intensity Mapping Pathfinder for the South Pole Telescope. https://doi.org/10.1007/s10909-022-02702-2

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