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A new estimation of the Archeops angular power spectrum

M. Tristram
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Abstract

We present a refined angular power spectrum of the Cosmic Microwave Background (CMB) anisotropies using the Archeops last flight data. The estimation of the Cl described here is performed using Xspect, a method which uses the cross-power spectra of the maps of 6 different detectors. It covers multipole range from l=10 to l=700 in 25 bins and confirms a strong evidence of a plateau followed by the presence of two Doppler peaks. Archeops was conceived as a precursor of the Planck HFI instrument by using the same optical design and the same technology for the detectors and their cooling. Since last publication, specific methods have been developed, extra bolometers were used and the sky coverage, of about 20%, is almost twice larger. We also present a comparison with first-year WMAP data both using individually spectra and by computing the cross-power spectrum of the two experiments.

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M. Tristram. 2004-08-19. A new estimation of the Archeops angular power spectrum. https://arxiv.org/abs/astro-ph/0408358

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