HAL : hal-00296577, version 1
 arXiv : 0807.1113
 Code Bibliographique ADS : 2008PhRvD..78h3013F
 Physical Review D 78, 8 (2008) 083013
 CMB power spectrum estimation using wavelets
 G. Faÿ1, F. Guilloux1, M. Betoule1, J.-F. Cardoso1, 2, J. Delabrouille1, M. Le Jeune1
 (30/10/2008)
 Observations of the Cosmic Microwave Background (CMB) provide increasingly accurate information about the structure of the Universe at the recombination epoch. Most of this information is encoded in the angular power spectrum of the CMB. The aim of this work is to propose a versatile and powerful method for spectral estimation on the sphere which can easily deal with non-stationarity, foregrounds and multiple experiments with various specifications. In this paper, we use needlets (wavelets) on the sphere to construct natural and efficient spectral estimators for partially observed and beamed CMB with non stationary noise. In the case of a single experiment, we compare this method with Pseudo-$C_\ell$ methods. The performance of the needlet spectral estimators (NSE) compares very favorably to the best Pseudo--$C_\ell$ estimators, over the whole multipole range. On simulations with a simple model (CMB + uncorrelated noise with known variance per pixel + mask), they perform uniformly better. Their distinctive ability to aggregate many different experiments, to control the propagation of errors and to produce a single wide-band error bars is highlighted. The needlet spectral estimator is a powerful, tunable tool which is very well suited to angular power spectrum estimation of spherical data such as incomplete and noisy CMB maps.
 équipe(s) de recherche : APC - ADAMIS
 Domaine : Physique/Astrophysique/Cosmologie et astrophysique extra-galactiquePlanète et Univers/Astrophysique/Cosmologie et astrophysique extra-galactiqueStatistiques/MéthodologieStatistiques/ApplicationsPlanète et Univers/Astrophysique
 Mots Clés : Spectral estimation – Cosmic Microwave Background – Needlets – Aggregation of estimators
 Lien vers le texte intégral : http://fr.arXiv.org/abs/0807.1113
 hal-00296577, version 1 http://hal.archives-ouvertes.fr/hal-00296577 oai:hal.archives-ouvertes.fr:hal-00296577 Contributeur : Frédéric Guilloux <> Soumis le : Samedi 12 Juillet 2008, 01:54:51 Dernière modification le : Vendredi 22 Juin 2012, 21:46:08