SuMAC: On-sky demonstration of multi-pixel on-chip millimeter-wave spectroscopy at the Large Millimeter Telescope

Marcial Becerril-Tapia; Peter S. Barry; Christopher S. Benson; Charles M. Bradford; Thomas L. R. Brien; Scott C. Chapman; Simon Doyle; Víctor Gómez-Rivera; Steven Hailey-Dunsheath; Jesús Hernández-Aguilar; José Luis Hernández-Rebollar; David H. Hughes; Elijah Kane; Kirit S. Karkare; Alex M. Lapuente; Ryan McGeehan; Raúl Naranjo-Romero; Andreas Papageorgiou; Joseph Redford; Iván Rodríguez-Montoya; Sam Rowe; David O. Sánchez-Argüelles; Sofia Savorgnano; Annie Tan; Jair Vega-Méndez

arXiv · 2608.03789

SuMAC: On-sky demonstration of multi-pixel on-chip millimeter-wave spectroscopy at the Large Millimeter Telescope

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Abstract

The SuperSpec-MUSCAT Collaboration (SuMAC) is an effort to operate SuperSpec spectrometers in the MUSCAT instrument at the Large Millimeter Telescope (LMT). SuperSpec is an on-chip filterbank spectrometer using kinetic inductance detectors (KIDs), with moderate $R\sim 200$ spectral resolution for observing in the 1 mm atmospheric window (190-300 GHz). While nominally a continuum camera operating a 1.1 mm, MUSCAT was also designed to operate as a testbed for pioneering detection technologies. In July 2025, three SuperSpec devices were installed and commissioned in the MUSCAT cryostat with minimal modifications to the system. This work presents an overview of SuperSpec's deployment and performance in MUSCAT along with the main results from the Summer 2025 observation campaign. Highlights include the detection of CO emission line in the galaxy NGC253, mapping the Orion KL region, and preliminary line intensity mapping scans.

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Marcial Becerril-Tapia, Peter S. Barry, Christopher S. Benson, Charles M. Bradford, Thomas L. R. Brien, Scott C. Chapman, Simon Doyle, Víctor Gómez-Rivera, Steven Hailey-Dunsheath, Jesús Hernández-Aguilar, José Luis Hernández-Rebollar, David H. Hughes, Elijah Kane, Kirit S. Karkare, Alex M. Lapuente, Ryan McGeehan, Raúl Naranjo-Romero, Andreas Papageorgiou, Joseph Redford, Iván Rodríguez-Montoya, Sam Rowe, David O. Sánchez-Argüelles, Sofia Savorgnano, Annie Tan, Jair Vega-Méndez. 2026-08-04. SuMAC: On-sky demonstration of multi-pixel on-chip millimeter-wave spectroscopy at the Large Millimeter Telescope. https://arxiv.org/abs/2608.03789

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