The LMT 2 Millimeter Receiver System (B4R). I. Overview and Results of Science Demonstration
Journal article, 2025
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 mu 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.
Author
Ryohei Kawabe
The Graduate University for Advanced Studies (SOKENDAI)
National Institutes of Natural Sciences
Takeshi Sakai
University of Electro-Communications
Kunihiko Tanaka
Keio University
Akio Taniguchi
Kitami Institute of Technology
Nagoya University
Bunyo Hatsukade
The Graduate University for Advanced Studies (SOKENDAI)
University of Tokyo
National Institutes of Natural Sciences
Yoichi Tamura
Nagoya University
Yuki Yoshimura
University of Tokyo
Tatsuya Takekoshi
Kitami Institute of Technology
University of Tokyo
Tai Oshima
National Institutes of Natural Sciences
The Graduate University for Advanced Studies (SOKENDAI)
Masato Hagimoto
Nagoya University
Teppei Yonetsu
Osaka Metropolitan University
Kotomi Taniguchi
National Institutes of Natural Sciences
The Graduate University for Advanced Studies (SOKENDAI)
Kotaro Kohno
University of Tokyo
Hiroyuki Maezawa
Osaka Metropolitan University
David H. Hughes
National Institute of Astrophysics, Optics and Electronics
Peter F. Schloerb
University of Massachusetts
Edgar Colin-Beltran
National Council for Science and Technology Mexico
National Institute of Astrophysics, Optics and Electronics
Miguel Chavez Dagostino
National Institute of Astrophysics, Optics and Electronics
Victor Gomez-Rivera
National Institute of Astrophysics, Optics and Electronics
Crp Mexicana Invest Mat SA CV
Arturo I. Gomez-Ruiz
National Council for Science and Technology Mexico
National Institute of Astrophysics, Optics and Electronics
Gopal Narayanan
University of Massachusetts
Ivan Rodriguez-Montoya
National Council for Science and Technology Mexico
National Institute of Astrophysics, Optics and Electronics
David Sanchez-Arguelles
National Institute of Astrophysics, Optics and Electronics
National Council for Science and Technology Mexico
Yoshito Shimajiri
National Institutes of Natural Sciences
Kyushu Kyoritsu Univ
Kamal Souccar
University of Massachusetts
Min S. Yun
University of Massachusetts
Tom Bakx
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Kevin C. Harrington
National Astronomical Observatory of Japan
Atacama Large Millimeter-submillimeter Array (ALMA)
European Southern Observatory Santiago
Shinji Fujita
The Institute of Statistical Mathematics
Fumitaka Nakamura
National Institutes of Natural Sciences
The Graduate University for Advanced Studies (SOKENDAI)
University of Tokyo
O. S. Rojas-Garcia
National Institute of Astrophysics, Optics and Electronics
Alfredo A. Montana Barbano
National Institute of Astrophysics, Optics and Electronics
Javier Zaragoza-Cardiel
National Institute of Astrophysics, Optics and Electronics
National Council for Science and Technology Mexico
Astronomical Journal
0004-6256 (ISSN) 1538-3881 (eISSN)
Vol. 170 6 350Subject Categories (SSIF 2025)
Atom and Molecular Physics and Optics
Astronomy, Astrophysics, and Cosmology
DOI
10.3847/1538-3881/ae12eb