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arXiv · 2509.02245

Spectral characterization and performance of SPT-SLIM on-chip filterbank spectrometers

C. S. Benson·K. Fichman·M. Adamic·A. J. Anderson·P. S. Barry·B. A. Benson·E. Brooks·J. E. Carlstrom·T. Cecil·C. L. Chang·K. R. Dibert·M. Dobbs·K. S. Karkare·G. K. Keating·A. M. Lapuente·M. Lisovenko·D. P. Marrone·J. Montgomery·T. Natoli·Z. Pan·A. Rahlin·G. Robson·M. Rouble·G. Smecher·V. Yefremenko·M. R. Young·C. Yu·J. A. Zebrowski·C. Zhang
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Abstract

The South Pole Telescope Shirokoff Line Intensity Mapper (SPT-SLIM) experiment is a pathfinder for demonstrating the use of on-chip spectrometers for millimeter (mm) Line Intensity Mapping (LIM). We present spectral bandpass measurements of the SPT-SLIM spectrometer channels made on site using a Fourier Transform Spectrometer during the first deployment of SPT-SLIM in the 2024-2025 Austral summer season. We note the effect of FTS systematics on measurements of on-chip filterbank spectrometer resolutions and demonstrate a technique for measuring the narrow band passes of the SPT-SLIM filterbanks that improves beyond the intrinsic resolution of a Fourier Transform Spectrometer.

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C. S. Benson, K. Fichman, M. Adamic, A. J. Anderson, P. S. Barry, B. A. Benson, E. Brooks, J. E. Carlstrom, T. Cecil, C. L. Chang, K. R. Dibert, M. Dobbs, K. S. Karkare, G. K. Keating, A. M. Lapuente, M. Lisovenko, D. P. Marrone, J. Montgomery, T. Natoli, Z. Pan, A. Rahlin, G. Robson, M. Rouble, G. Smecher, V. Yefremenko, M. R. Young, C. Yu, J. A. Zebrowski, C. Zhang. 2025-09-02. Spectral characterization and performance of SPT-SLIM on-chip filterbank spectrometers. https://doi.org/10.1109/tasc.2026.3694583

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