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تسجيل مستخدم جديدAngular power spectrum of the FastICA CMB component from BEAST data
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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 ODwyer 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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