FINER: Far-Infrared Nebular Emission Receiver for the Large Millimeter Telescope

TL;DR

FINER is a new dual-polarization receiver for the Large Millimeter Telescope, enabling wideband, high-resolution spectroscopic observations of distant galaxies to study their formation during the early universe.

Contribution

The paper introduces FINER, a novel superconductor-insulator-superconductor mixer receiver with wide bandwidth and high spectral resolution for the LMT, inspired by ALMA's technology.

Findings

Developed a dual-polarization SIS mixer receiver covering 120-360 GHz.

Achieves 5 times wider bandwidth than ALMA for the LMT.

Enables detailed spectral scans of distant galaxies in the northern hemisphere.

Abstract

Unveiling the emergence and prevalence of massive/bright galaxies during the epoch of reionization and beyond, within the first 600 million years of the Universe, stands as a pivotal pursuit in astronomy. Remarkable progress has been made by JWST in identifying an immense population of bright galaxies, which hints at exceptionally efficient galaxy assembly processes. However, the underlying physical mechanisms propelling their rapid growth remain unclear. With this in mind, millimeter and submillimeter-wave spectroscopic observations of redshifted far-infrared spectral lines, particularly the [O III] 88 micron and [C II] 158 micron lines, offers a crucial pathway to address this fundamental query. To this end, we develop a dual-polarization sideband-separating superconductor-insulator-superconductor (SIS) mixer receiver, FINER, for the Large Millimeter Telescope (LMT) situated in Mexico. Harnessing advancements from ALMA's wideband sensitivity upgrade (WSU) technology, FINER covers radio frequencies spanning 120-360 GHz, delivering an instantaneous intermediate frequency (IF) of 3-21 GHz per sideband per polarization, which is followed by a set of 10.24 GHz-wide digital spectrometers. At 40% of ALMA's light-collecting area, the LMT's similar atmospheric transmittance and FINER's 5 times wider bandwidth compared to ALMA culminate in an unparalleled spectral scanning capability in the northern hemisphere, paving the way for finer spectral-resolution detection of distant galaxies.