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Galactic contamination in the QMAP experiment

Angelica de Oliveira-Costa·Max Tegmark·Mark J. Devlin·L. M. Haffner·Tom Herbig·Amber D. Miller·Lyman A. Page·Ron J. Reynolds·S. L. Tufte
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Abstract

We quantify the level of foreground contamination in the QMAP Cosmic Microwave Background (CMB) data with two objectives: (a) measuring the level to which the QMAP power spectrum measurements need to be corrected for foregrounds and (b) using this data set to further refine current foreground models. We cross-correlate the QMAP data with a variety of foreground templates. The 30 GHz Ka-band data is found to be significantly correlated with the Haslam 408 MHz and Reich and Reich 1420 MHz synchrotron maps, but not with the Diffuse Infrared Background Experiment (DIRBE) 240, 140 and 100 micron maps or the Wisconsin H-Alpha Mapper (WHAM) survey. The 40 GHz Q-band has no significant template correlations. We discuss the constraints that this places on synchrotron, free-free and dust emission. We also reanalyze the foreground-cleaned Ka-band data and find that the two band power measurements are lowered by 2.3% and 1.3%, respectively.

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Angelica de Oliveira-Costa, Max Tegmark, Mark J. Devlin, L. M. Haffner, Tom Herbig, Amber D. Miller, Lyman A. Page, Ron J. Reynolds, S. L. Tufte. 2000-03-08. Galactic contamination in the QMAP experiment. https://doi.org/10.1086/312909

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