FINER: development of the wideband millimeter-wave receiver system and preparations for first light on the Large Millimeter Telescope

Akio Taniguchi; Yoichi Tamura; Takeshi Sakai; Masato Hagimoto; Takuya Hashimoto; Akio K. Inoue; Shun Ishii; Haoran Kang; Masato Kato; Ryohei Kawabe; Kotaro Kohno; Takafumi Kojima; Kianhong Lee; Sho Masui; Akinobu Miyake; Taku Nakajima; Tai Oshima; Wenlei Shan; Tatsuya Takekoshi; Kunihiko Tanaka; Kotomi Taniguchi; Kaoru Tsuji; Issei Watanabe; Tom J. L. C. Bakx; Yoshinobu Fudamoto; Kazuyuki Fujita; Yuichi Harikane; Bunyo Hatsukade; David H. Hughes; Takahiro Iino; Yuki Kimura; Hiroyuki Maezawa; Yuichi Matsuda; Ken Mawatari; Shunichi Nakatsubo; Hideo Sagawa; Peter F. Schloerb; Shigeru Takahashi; Akiyoshi Tsujita; Hideki Umehata; Min S. Yun

arXiv · 2607.03265

FINER: development of the wideband millimeter-wave receiver system and preparations for first light on the Large Millimeter Telescope

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Abstract

The recent discovery of an excess of luminous galaxies in the early Universe necessitates sensitive and wideband millimeter spectroscopy to understand their rapid growth. To address this, we present the development of the Far-Infrared Nebular Emission Receiver (FINER) for the Large Millimeter Telescope (LMT). The FINER frontend comprises two receivers covering 120-350 GHz (corresponding to ALMA Bands 4+5 and 6+7). The warm optics are designed to enable simultaneous two-band observations. Combined with the 10.24-GHz-wide digital spectrometer array, the system aims to deliver an instantaneous bandwidth approximately five times wider than current ALMA capabilities. We report that the 210-350 GHz receiver has already achieved commissioning-level performance, with sideband rejection further enhanced by the digital sideband separation technique. With installation expected in 2026, we discuss parallel preparations, including integrated testing and commissioning plans for first-look targets.

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Akio Taniguchi, Yoichi Tamura, Takeshi Sakai, Masato Hagimoto, Takuya Hashimoto, Akio K. Inoue, Shun Ishii, Haoran Kang, Masato Kato, Ryohei Kawabe, Kotaro Kohno, Takafumi Kojima, Kianhong Lee, Sho Masui, Akinobu Miyake, Taku Nakajima, Tai Oshima, Wenlei Shan, Tatsuya Takekoshi, Kunihiko Tanaka, Kotomi Taniguchi, Kaoru Tsuji, Issei Watanabe, Tom J. L. C. Bakx, Yoshinobu Fudamoto, Kazuyuki Fujita, Yuichi Harikane, Bunyo Hatsukade, David H. Hughes, Takahiro Iino, Yuki Kimura, Hiroyuki Maezawa, Yuichi Matsuda, Ken Mawatari, Shunichi Nakatsubo, Hideo Sagawa, Peter F. Schloerb, Shigeru Takahashi, Akiyoshi Tsujita, Hideki Umehata, Min S. Yun. 2026-07-03. FINER: development of the wideband millimeter-wave receiver system and preparations for first light on the Large Millimeter Telescope. https://arxiv.org/abs/2607.03265

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