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We describe a fast and accurate method for estimation of the cosmic microwave background (CMB) anisotropy angular power spectrum — Monte Carlo Apodised Spherical Transform EstimatoR. Originally devised for use in the interpretation of the Boomerang experimental data, MASTER is both a computationally efficient method suitable for use with the currently(More)
We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400 deg 2 patch of sky centered on RA 0h, Dec. −57.5 •. The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven(More)
We present an analysis of the Minkowski Functionals (MFs) describing the WMAP three-year temperature maps to place limits on possible levels of primordial non-Gaussianity. In particular, we apply perturbative formulae for the MFs to give constraints on the usual non-linear coupling constant f NL. The theoretical predictions are found to agree with the MFs(More)
We apply the Gabor transform methodology proposed in (Hansen et al. 2002, 2003) to the WMAP data in order to test the statistical properties of the CMB fluctuation field and specifically to evaluate the fundamental assumption of cosmological isotropy. In particular, we apply the transform with several apodisation scales, thus allowing the determination of(More)
We report on the results from two independent but complementary statistical analyses of the WMAP data. In the first, the data are subjected to an N-point correlation function analysis, and in the second to a power spectrum analysis. We focus on large and intermediate scales (larger than about 3 •), and compare the observed data on these scales against Monte(More)
Context. The Planck satellite will map the full sky at nine frequencies from 30 to 857 GHz. The CMB intensity and polarization that are its prime targets are contaminated by foreground emission. Aims. The goal of this paper is to compare proposed methods for separating CMB from foregrounds based on their different spectral and spatial characteristics, and(More)
In our recent paper (Yadav et al. 2007) we described a fast cubic (bispectrum) estimator of the amplitude of primordial non-Gaussianity of local type, f N L , from a combined analysis of the Cosmic Microwave Background (CMB) temperature and E-polarization observations. In this paper we generalize the estimator to deal with a partial sky coverage as well as(More)
Motivated by the recent results of Hansen et al. (2008) concerning a noticeable hemispherical power asymmetry in the WMAP data on small angular scales, we revisit the dipole modulated signal model introduced by Gordon et al. (2005). This model assumes that the true CMB signal consists of a Gaussian isotropic random field modulated by a dipole, and is(More)
Motivated by the large-scale asymmetry observed in the cosmic microwave background sky, we consider a specific class of anisotropic cosmological models – Bianchi type VII h – and compare them to the WMAP first-year data on large angular scales. Remarkably, we find evidence of a correlation which is ruled out as a chance alignment at the 3σ level. The best(More)
We investigate local variations of the primordial non-Gaussianity parameter f N L in the WMAP data, looking for possible influence of foreground contamination in the full-sky estimate of f N L. We first improve the needlet bispectrum estimate in (Rudjord et al. 2009) on the full-sky to f N L = 73±31 using the KQ75 mask on the co-added V+W channel. We find(More)