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NASA NTRS · 20260008661

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

Parham Zarei·Pedro Villalba-Gonzalez·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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Cosmic microwave backgroundGalactic foregroundssynchrotron emissioncosmologyinflation

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Parham Zarei, Pedro Villalba-Gonzalez, 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. 2026-08-20. The Canadian Galactic Emission Mapper (CGEM) A Cosmic Microwave Foreground Experiment. https://ntrs.nasa.gov/citations/20260008661

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