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arXiv · 2102.08280

Large format imaging spectrograph for the Large Submillimeter Telescope (LST)

K. Kohno·R. Kawabe·Y. Tamura·A. Endo·J. J. A. Baselmans·K. Karatsu·A. K. Inoue·K. Moriwaki·N. H. Hayatsu·N. Yoshida·Y. Yoshimura·B. Hatsukade·H. Umehata·T. Oshima·T. Takekoshi·A. Taniguchi·P. D. Klaassen·T. Mroczkowski·C. Cicone·F. Bertoldi·H. Dannerbauer·T. Tosaki
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Abstract

We present a conceptual study of a large format imaging spectrograph for the Large Submillimeter Telescope (LST) and the Atacama Large Aperture Submillimeter Telescope (AtLAST). Recent observations of high-redshift galaxies indicate the onset of earliest star formation just a few 100 million years after the Big Bang (i.e., z = 12--15), and LST/AtLAST will provide a unique pathway to uncover spectroscopically-identified first forming galaxies in the pre-reionization era, once it will be equipped with a large format imaging spectrograph. We propose a 3-band (200, 255, and 350 GHz), medium resolution (R = 2,000) imaging spectrograph with 1.5 M detectors in total based on the KATANA concept (Karatsu et al. 2019), which exploits technologies of the integrated superconducting spectrometer (ISS) and a large-format imaging array. A 1-deg2 drilling survey (3,500 hr) will capture a large number of [O III] 88 um (and [C II] 158 um) emitters at z = 8--9, and constrain [O III] luminosity functions at z > 12.

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K. Kohno, R. Kawabe, Y. Tamura, A. Endo, J. J. A. Baselmans, K. Karatsu, A. K. Inoue, K. Moriwaki, N. H. Hayatsu, N. Yoshida, Y. Yoshimura, B. Hatsukade, H. Umehata, T. Oshima, T. Takekoshi, A. Taniguchi, P. D. Klaassen, T. Mroczkowski, C. Cicone, F. Bertoldi, H. Dannerbauer, T. Tosaki. 2021-02-16. Large format imaging spectrograph for the Large Submillimeter Telescope (LST). https://doi.org/10.1117/12.2561238

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