Pages

Instrument papers

Kang, H., Kojima, T., Sakai, T., Tamura, Y., Ishii, S., et al. 2026, “A Wideband Millimeter-wave Receiver at 210–350 GHz for LMT-FINER”, Proc. SPIE, arXiv:2606.25637
Taniguchi, A., Tamura, Y., Sakai, T., Hagimoto, M., Hashimoto, T., et al. 2026, “FINER: development of the wideband millimeter-wave receiver system and preparations for first light on the Large Millimeter Telescope”, Proc. SPIE, arXiv:2607.03265
Tamura, Y., Sakai, T., Kawabe, R., Kojima, T., Taniguchi, A., et al. 2024, “FINER: Far-Infrared Nebular Emission Receiver for the Large Millimeter Telescope”, Proc. SPIE, 13102, 131020G, doi:10.1117/12.3017788, arXiv:2406.07975
Kang, H., et al. 2024, “Development status of wideband millimeter-wave receivers for LMT-FINER”, Proc. SPIE, 13102, 131020J, doi:10.1117/12.3018190, arXiv:2406.07974
Hagimoto, M., Taniguchi, A., et al. 2024, “A 10.24-GHz-wide digital spectrometer array system for LMT-FINER: system design and laboratory performance verification”, Proc. SPIE, 13102, 131020V, doi:10.1117/12.3018296, arXiv:2406.07978

B4R, the precursor of FINER

Yonetsu, T., Kawabe, R., Yoshimura, Y., Taniguchi, K., Shimajiri, Y., et al. 2025, “The LMT 2 millimeter receiver system (B4R). II. Science demonstration observations toward Orion-KL/OMC-1”, arXiv:2511.21845
Kawabe, R., Sakai, T., Tanaka, K., Taniguchi, A., Hatsukade, B., Tamura, Y., et al. 2025, “The LMT 2 Millimeter Receiver System (B4R). I. Overview and Results of Science Demonstration”, AJ, 170, 350, doi:10.3847/1538-3881/ae12eb

SIS mixer technology

Kojima, T., et al. 2020, A&A, 640, L9 (ADS)
Kojima, T., et al. 2017, IEEE Trans. Terahertz Sci. Technol., 7, 694 (ADS)

FINER will be offered on the LMT through the regular LMT Call for Proposals after commissioning. Observing time on the LMT is allocated to the LMT partner communities, and eligibility to propose follows the rules of each Call; there is currently no formal route for proposers outside the LMT partnership.

When does FINER come online?

FINER is expected to come online in 2027, after installation and commissioning on the LMT.

Receiver

Specifications

FINER is a dual-polarization, sideband-separating (2SB) SIS receiver system. The table below summarizes the configuration installed for first light and the design goals of the full system.

General
Number of bands	2 (one band observed at a time at first light)
Number of beams per band	1
Number of polarizations per band	2
Number of sidebands per band	2 (2SB)

	Band 4 (first light)	Band 6+7	Band 4+5 (planned upgrade)
Radio frequency	≈138–178 GHz	≈210–351 GHz	120–210 GHz
Intermediate frequency (per sideband, per polarization)	4–8 GHz	4–20 GHz	4–20 GHz
Receiver noise temperature (SSB, design goal)	—	75 K	45 K

Measured performance will be reported here after commissioning on the LMT.

Science

Galaxy formation in the first half of the epoch of reionization

Background

The James Webb Space Telescope (JWST) has found more than a hundred candidate galaxies at redshifts z > 8, when the Universe was less than about 600 million years old, and has confirmed some of them spectroscopically out to z ≈ 14. The bright end of their ultraviolet luminosity function evolves surprisingly little with redshift (Harikane et al. 2022), which means that massive galaxies had to grow very efficiently within a short time. This places a stringent constraint on models of cosmic structure formation.