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arXiv · 1608.03707

ABS: an Analytical method of Blind Separation of CMB from foregrounds

Pengjie Zhang·Jun Zhang·Le Zhang
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Abstract

Extracting CMB B-mode polarization from complicated foregrounds is a challenging task in searching for inflationary gravitational waves. We propose the ABS method as a blind and analytical solution to this problem. It applies to the measured cross bandpower between different frequency bands and obtains the CMB B-mode bandpower analytically. It does not rely on assumptions of foregrounds and does not require multiple parameter fitting. Testing against a variety of foregrounds, survey frequency configurations and instrument noise, we verify its applicability and numerical stability. The ABS method also applies to CMB temperature, E-mode polarization, the thermal Sunyaev Zel'dovich effect, spectral distortion, and even significantly different problems such as cosmic magnification.

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Pengjie Zhang, Jun Zhang, Le Zhang. 2019-01-08. ABS: an Analytical method of Blind Separation of CMB from foregrounds. https://arxiv.org/abs/1608.03707

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