The LMT 2 Millimeter Receiver System (B4R). I. Overview and Results of Science Demonstration

Abstract We report on the results of the on-sky test and science demonstration conducted with the 2 mm receiver system, B4R, on the 50 m Large Millimeter Telescope (LMT), located at an altitude of 4600 m in Mexico. The B4R receiver was developed based on the dual-polarization sideband-separating mixer technology of the Atacama Large Millimeter/submillimeter Array and is equipped with a fast Fourier transform digital spectrometer, XFFTS. The primary science objective is the spectroscopic redshift identification of high-redshift dusty star-forming galaxies, complementing the existing 3 mm Redshift Search Receiver by enabling the detection of multiple carbon monoxide lines. Additionally, the B4R receiver broadens the range of science cases possible with the LMT, including astrochemistry, as the 2 mm band encompasses unique molecular lines such as deuterated molecules and shock tracers. During on-site commissioning in 2018 and 2019, we successfully demonstrated on-the-fly mapping and position-switching observations toward the Orion Molecular Cloud 1 and bright high-redshift dusty star-forming galaxies, respectively. We confirmed that the installed B4R system largely met its basic performance specifications. Furthermore, we measured the LMT’s aperture efficiencies across the entire B4R frequency range (130–160 GHz), finding them to be roughly consistent with expectations based on a surface accuracy of 100 μ m and the receiver optics design. These results with the B4R will enable the most sensitive single-dish spectroscopic observations at 2 mm using the LMT.

Authors

Institutions

Publication Details

Journal
The Astronomical Journal
Published
2025-11-24
DOI
https://doi.org/10.3847/1538-3881/ae12eb
Primary Topic
Superconducting and THz Device Technology
Type
article
Field-Weighted Citation Impact
0.00
Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
article

The LMT 2 Millimeter Receiver System (B4R). I. Overview and Results of Science Demonstration

Ryohei Kawabe, Gopal Narayanan, Bunyo Hatsukade, Yoichi Tamura et al.
The Astronomical Journal
Superconducting and THz Device Technology
article

The LMT 2 Millimeter Receiver System (B4R). I. Overview and Results of Science Demonstration

Ryohei Kawabe, Gopal Narayanan, Bunyo Hatsukade, Yoichi Tamura, Teppei Yonetsu, Iván Rodríguez-Montoya, Kevin C. Harrington, Kamal Souccar, Kunihiko Tanaka, Tatsuya Takekoshi, Anastasia Maria Barbano, Edgar Colín-Beltrán, Min S. Yun, Takeshi Sakai, P. Schloerb, Javier Zaragoza-Cardiel, Yuki Yoshimura, Shinji Fujita, O. S. Rojas-García, Arturo I. Gómez-Ruiz, David Sánchez-Argüelles, Víctor Gómez-Rivera, Akio Taniguchi, Fumitaka Nakamura, H. Maezawa, Kotomi Taniguchi, Masato Hagimoto, Kotaro Kohno, Tom J. L. C. Bakx, Yoshito Shimajiri, M. Chávez, Tai Oshima, D. H. Hughes
article en

Abstract

Abstract We report on the results of the on-sky test and science demonstration conducted with the 2 mm receiver system, B4R, on the 50 m Large Millimeter Telescope (LMT), located at an altitude of 4600 m in Mexico. The B4R receiver was developed based on the dual-polarization sideband-separating mixer technology of the Atacama Large Millimeter/submillimeter Array and is equipped with a fast Fourier transform digital spectrometer, XFFTS. The primary science objective is the spectroscopic redshift identification of high-redshift dusty star-forming galaxies, complementing the existing 3 mm Redshift Search Receiver by enabling the detection of multiple carbon monoxide lines. Additionally, the B4R receiver broadens the range of science cases possible with the LMT, including astrochemistry, as the 2 mm band encompasses unique molecular lines such as deuterated molecules and shock tracers. During on-site commissioning in 2018 and 2019, we successfully demonstrated on-the-fly mapping and position-switching observations toward the Orion Molecular Cloud 1 and bright high-redshift dusty star-forming galaxies, respectively. We confirmed that the installed B4R system largely met its basic performance specifications. Furthermore, we measured the LMT’s aperture efficiencies across the entire B4R frequency range (130–160 GHz), finding them to be roughly consistent with expectations based on a surface accuracy of 100 μ m and the receiver optics design. These results with the B4R will enable the most sensitive single-dish spectroscopic observations at 2 mm using the LMT.

The Astronomical JournalVol. 170(6)
Kyushu Kyoritsu University (JP), National Institutes of Natural Sciences (JP), The Graduate University for Advanced Studies, SOKENDAI (JP), Keio University (JP), University of Electro-Communications (JP), University of Massachusetts Amherst (US), Atacama Large Millimeter Submillimeter Array (CL), Mexican Academy of Sciences (MX), National Institute of Astrophysics, Optics and Electronics (MX), European Southern Observatory (CL), The Institute of Statistical Mathematics (JP), National Astronomical Observatory of Japan (JP), Secretaría de Ciencia, Humanidades, Tecnología e Innovación (MX), Osaka Metropolitan University (JP), Nagoya University (JP), Chalmers University of Technology (SE), The University of Tokyo (JP), Kitami Institute of Technology (JP)
Openalex Percentile: Top 75%
Superconducting and THz Device Technology
DOIOpen Access PDFOpenAlex
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.