The CMB temperature power spectrum from an improved analysis of the Archeops data

¹ Laboratoire de Physique Subatomique et de Cosmologie, 53 avenue des Martyrs, 38026 Grenoble Cedex, France e-mail: reprints@archeops.org;tristram@lpsc.in2p3.fr
² Department of Physics & Astronomy, University of British Columbia, Vancouver, Canada
³ Cardiff University, Physics Department, PO Box 913, 5, The Parade, Cardiff, CF24 3YB, UK
⁴ University of California, Berkeley, Dept. of Astronomy, 601 Campbell Hall, Berkeley, CA 94720-3411, USA
⁵ Laboratoire de l'Accélérateur Linéaire, BP 34, Campus Orsay, 91898 Orsay Cedex, France
⁶ CEA-CE Saclay, DAPNIA, Service de Physique des Particules, Bât. 141, 91191 Gif-sur-Yvette Cedex, France
⁷ APC, 11 Pl. M. Berthelot, 75231 Paris Cedex 5, France
⁸ Centre de Recherche sur les Très Basses Températures, BP 166, 38042 Grenoble Cedex 9, France
⁹ Centre d'Étude Spatiale des Rayonnements, BP 4346, 31028 Toulouse Cedex 4, France
¹⁰ Laboratoire d'Astrophysique de Tarbes Toulouse, 14 avenue E. Belin, 31400 Toulouse, France
¹¹ California Institute of Technology, 105-24 Caltech, 1201 East California Blvd, Pasadena CA 91125, USA
¹² Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, California 91109, USA
¹³ Institut d'Astrophysique de Paris, 98bis boulevard Arago, 75014 Paris, France
¹⁴ CNRS-ENST, 46 rue Barrault, 75634 Paris, France
¹⁵ Gruppo di Cosmologia Sperimentale, Dipart. di Fisica, Univ. “La Sapienza”, PA Moro, 2, 00185 Roma, Italy
¹⁶ Laboratoire d'Astrophysique, Obs. de Grenoble, BP 53, 38041 Grenoble Cedex 9, France
¹⁷ CSNSM-IN2P3, Bât. 108, 91405 Orsay Campus, France
¹⁸ CEA-CE Saclay, DAPNIA, Service d'Astrophysique, Bât. 709, 91191 Gif-sur-Yvette Cedex, France
¹⁹ Institute for Astronomy, University of Hawaii, 2680 Woodlawn Dr, Honolulu, HI 96822, USA
²⁰ Institut d'Astrophysique Spatiale, Bât. 121, Université Paris XI, 91405 Orsay Cedex, France
²¹ LPNHE, Universités Paris VI et Paris VII, 4 place Jussieu, Tour 33, 75252 Paris Cedex 05, France
²² School of Physics and Astronomy, 116 Church St. SE, University of Minnesota, Minneapolis MN 55455, USA
²³ LERMA, Observatoire de Paris, 61 Av. de l'Observatoire, 75014 Paris, France

Received: 23 November 2004
Accepted: 16 February 2005

Abstract

We present improved results on the measurement of the angular power spectrum of the Cosmic Microwave Background (CMB) temperature anisotropies using the data from the last Archeops flight. This refined analysis is obtained by using the 6 most sensitive photometric pixels in the CMB bands centered at 143 and 217 GHz and 20% of the sky, mostly clear of foregrounds. Using two different cross-correlation methods, we obtain very similar results for the angular power spectrum. Consistency checks are performed to test the robustness of these results paying particular attention to the foreground contamination level which remains well below the statistical uncertainties. The multipole range from to is covered with 25 bins, confirming strong evidence for a plateau at large angular scales (the Sachs-Wolfe plateau) followed by two acoustic peaks centered around and respectively. These data provide an independent confirmation, obtained at different frequencies, of the Wmap first year results.