TIME Commissioning Observations: II. On-sky Characterization and the 2D Map Data Processing Pipeline

Benjamin J. Vaughan; Abigail T. Crites; Dongwoo T. Chung; Ryan P. Keenan; James J. Bock; Charles M. Bradford; Victoria L. Butler; Tzu-Ching Chang; Yun-Ting Cheng; Audrey Dunn; Nicholas Emerson; Clifford Frez; Jonathon Hunacek; Chao-Te Li; Ian N. Lowe; King Lau; Daniel P. Marrone; Evan C. Mayer; Sophie M. McAtee; Dang Pham; Shwetha Prakash; Guochao Sun; Isaac Trumper; Anthony D. Turner; Ta-Shun Wei; Selina F. Yang; Michael Zemcov

arXiv · 2607.01220

TIME Commissioning Observations: II. On-sky Characterization and the 2D Map Data Processing Pipeline

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Abstract

The Tomographic Ionized-carbon Mapping Experiment (TIME) is a line intensity mapping (LIM) instrument that is designed to observe the power spectrum of the [CII] $158$~$\mu$m emission line during the Epoch of Reionization. TIME completed a commissioning run in 2022 at the Arizona Radio Observatory onboard the 12-M Radio Telescope at Kitt Peak, where it observed galactic sources for the first time. In this paper we report on an analysis of observations of the Orion Molecular Cloud (OMC) and G49.5 (a local HII region). The OMC observations were taken at least once a day to assess the stability of the instrument and demonstrate its on-sky performance. We describe a spectral image processing pipeline to make calibrated maps of raster scans of these sources, incorporating planet observations for gain calibration. We show with G49.5 that, when compared to the Bolocam Galactic Plane Survey, we are able to achieve a $< 3\%$ calibration difference. Based on the outcomes from this commissioning phase of TIME, we have demonstrated preliminary performance, and identified sources of improvement necessary for pursuing a LIM measurement.

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Benjamin J. Vaughan, Abigail T. Crites, Dongwoo T. Chung, Ryan P. Keenan, James J. Bock, Charles M. Bradford, Victoria L. Butler, Tzu-Ching Chang, Yun-Ting Cheng, Audrey Dunn, Nicholas Emerson, Clifford Frez, Jonathon Hunacek, Chao-Te Li, Ian N. Lowe, King Lau, Daniel P. Marrone, Evan C. Mayer, Sophie M. McAtee, Dang Pham, Shwetha Prakash, Guochao Sun, Isaac Trumper, Anthony D. Turner, Ta-Shun Wei, Selina F. Yang, Michael Zemcov. 2026-07-01. TIME Commissioning Observations: II. On-sky Characterization and the 2D Map Data Processing Pipeline. https://arxiv.org/abs/2607.01220

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