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arXiv · 2609.00357

The Canadian Galactic Emission Mapper (CGEM): A Cosmic Microwave Foreground Experiment

Parham Zarei·Pedro Villalba-González·Mandana Amiri·Charles L. Bennett·Guinevere Berg·Mark Halpern·Gary Hinshaw·Gordon Lacy·Joshua MacEachern·Thomas J. Rennie·Shuyu van Kerkwijk·Bruce Veidt·Janet Weiland·Don Wiebe·Edward J. Wollack
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Abstract

The Canadian Galactic Emission Mapper (CGEM) is a 4-meter single-dish radio telescope located at the Dominion Radio Astrophysical Observatory (DRAO) in Penticton, Canada. CGEM is designed to map polarized Galactic synchrotron emission across the entire northern sky at 8-10 GHz with 1 MHz frequency resolution and 0.5 degree angular resolution. Its goal is to obtain high-fidelity, low-noise maps of polarized Galactic synchrotron radiation, at frequencies where synchrotron dominates, in order to provide a reliable template for CMB B-mode foreground cleaning. We will show on sky performance of CGEM's single-pixel azimuthally-symmetric telescope, its coherent, dual-polarized radiometer, and show maps made from commissioning data from the first few months of operation.

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Parham Zarei, Pedro Villalba-González, Mandana Amiri, Charles L. Bennett, Guinevere Berg, Mark Halpern, Gary Hinshaw, Gordon Lacy, Joshua MacEachern, Thomas J. Rennie, Shuyu van Kerkwijk, Bruce Veidt, Janet Weiland, Don Wiebe, Edward J. Wollack. 2026-08-31. The Canadian Galactic Emission Mapper (CGEM): A Cosmic Microwave Foreground Experiment. https://doi.org/10.1117/12.3105550

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