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Angular power spectrum of the FastICA CMB component from BEAST data

S. Donzelli·D. Maino·M. Bersanelli·J. Childers·N. Figueiredo·P. M. Lubin·P. R. Meinhold·I. J. O'Dwyer·M. D. Seiffert·T. Villela·B. D. Wandelt·C. A. Wuensche
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Abstract

We present the angular power spectrum of the CMB component extracted with FastICA from the Background Emission Anisotropy Scanning Telescope (BEAST) data. BEAST is a 2.2 meter off-axis telescope with a focal plane comprising 8 elements at Q (38-45 GHz) and Ka (26-36 GHz) bands. It operates from the UC White Mountain Research Station at an altitude of 3800 meters. The BEAST CMB angular power spectrum has been already calculated by O'Dwyer et.al. using only the Q band data. With two input channels FastICA returns two possible independent components. We found that one of these two has an unphysical spectral behaviour while the other is a reasonable CMB component. After a detailed calibration procedure based on Monte-Carlo (MC) simulations we extracted the angular power spectrum for the identified CMB component and found a very good agreement with the already published BEAST CMB angular power spectrum and with the WMAP data.

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S. Donzelli, D. Maino, M. Bersanelli, J. Childers, N. Figueiredo, P. M. Lubin, P. R. Meinhold, I. J. O'Dwyer, M. D. Seiffert, T. Villela, B. D. Wandelt, C. A. Wuensche. 2006-03-20. Angular power spectrum of the FastICA CMB component from BEAST data. https://doi.org/10.1111/j.1365-2966.2006.10320.x

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