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We discuss the derivation of the analytic properties of the cross-power spectrum estimator from multi-detector CMB anisotropy maps. The method is computationally convenient and it provides unbiased estimates under very broad assumptions. We…

天体物理学 · 物理学 2007-05-23 G. Polenta , D. Marinucci , A. Balbi , P. de Bernardis , E. Hivon , S. Masi , P. Natoli , N. Vittorio

In (Hansen et al. 2002) we presented a new approach for measuring non-Gaussianity of the Cosmic Microwave Background (CMB) anisotropy pattern, based on the multivariate empirical distribution function of the spherical harmonics a_lm of a…

天体物理学 · 物理学 2010-11-19 Frode K. Hansen , Domenico Marinucci , Nicola Vittorio

We present a new, model-independent approach for measuring non-Gaussianity of the Cosmic Microwave Background (CMB) anisotropy pattern. Our approach is based on the empirical distribution function of the normalized spherical harmonic…

天体物理学 · 物理学 2011-05-10 Frode K. Hansen , Domenico Marinucci , Paolo Natoli , Nicola Vittorio

We use simulated maps of the cosmic microwave background anisotropy to quantify the ability of different statistical tests to discriminate between Gaussian and non-Gaussian models. Despite the central limit theorem on large angular scales,…

天体物理学 · 物理学 2009-10-31 Nicholas G. Phillips , A. Kogut

We develop the tools necessary to assess the statistical significance of resonant features in the CMB correlation functions, combining power spectrum and bispectrum measurements. This significance is typically addressed by running a large…

宇宙学与河外天体物理 · 物理学 2016-03-02 P. Daniel Meerburg , Moritz Münchmeyer , Benjamin Wandelt

Gaussianity is the very base for derivation of the cosmological parameters from the CMB angular power spectrum. Non-Gaussian signal, whether originated from experimental error or primordial source, could mimic extra power in the power…

天体物理学 · 物理学 2009-11-11 Pavel Naselsky , Lung-Yih Chiang , Poul Olesen , Igor Novikov

Since the inhomogeneous instrument noise can produce extra non-Gaussianity in the CMB anisotropy, its effect should be carefully subtracted in the primordial non-Gaussianity estimation. We calculate the probability distribution function of…

天体物理学 · 物理学 2009-02-23 B. Yu , T. Lu

We describe an approximate statistical model for the sample variance distribution of the non-linear matter power spectrum that can be calibrated from limited numbers of simulations. Our model retains the common assumption of a multivariate…

天体物理学 · 物理学 2008-09-22 Michael D. Schneider , Lloyd Knox , Salman Habib , Katrin Heitmann , David Higdon , Charles Nakhleh

We explore power spectrum estimation in the context of a Gaussian approximation to the likelihood function. Using the Saskatoon data, we estimate the power averaged through a set of ten filters designed to make the errors on the power…

天体物理学 · 物理学 2007-05-23 Lloyd Knox , J. Richard Bond , Andrew H. Jaffe

We analyse the large-scale coherence of the CMB anisotropy field with non-gaussian initial conditions usind 2-point function of the power fluctuations in the wavelet space. Employing the multivariate Edgeworth expansion (MEE) we constrain…

天体物理学 · 物理学 2009-10-30 Lucia Popa

Powerful constraints on theories can already be inferred from existing CMB anisotropy data. But performing an exact analysis of available data is a complicated task and may become prohibitively so for upcoming experiments with \gtrsim10^4…

天体物理学 · 物理学 2009-10-30 J. R. Bond , A. H. Jaffe , L. E. Knox

We propose a formalism for estimating the skewness and angular power spectrum of a general Cosmic Microwave Background data set. We use the Edgeworth Expansion to define a non-Gaussian likelihood function that takes into account the…

天体物理学 · 物理学 2010-04-30 C. R. Contaldi , P. G. Ferreira , J. Magueijo , K. M. Gorski

Upcoming surveys will measure the cosmic microwave background (CMB) weak lensing power spectrum in exquisite detail, allowing for strong constraints on the sum of neutrino masses among other cosmological parameters. Standard CMB lensing…

宇宙学与河外天体物理 · 物理学 2024-08-23 Delon Shen , Emmanuel Schaan , Simone Ferraro

We present a Bayesian angular power spectrum and signal map inference engine which can be adapted to interferometric observations of anisotropies inthe cosmic microwave background, 21 cm emission line mapping of galactic brightness…

宇宙学与河外天体物理 · 物理学 2015-05-30 P. M. Sutter , Benjamin D. Wandelt , Siddharth Malu

As the Cosmic Microwave Background (CMB) radiation is observed to higher and higher angular resolution the size of the resulting datasets becomes a serious constraint on their analysis. In particular current algorithms to determine the…

天体物理学 · 物理学 2007-05-23 Julian Borrill

Measurement of Cosmic Microwave Background (CMB) anisotropies has been playing a lead role in precision cosmology by providing some of the tightest constrains on cosmological models and parameters. However, precision can only be meaningful…

宇宙学与河外天体物理 · 物理学 2015-04-16 Santanu Das , Sanjit Mitra , Sonu Tabitha Paulson

The assumption of Gaussianity of the primordial perturbations plays an important role in modern cosmology. The most direct test of this hypothesis consists in testing Gaussianity of the CMB maps. Counting the pixels with the temperatures in…

天体物理学 · 物理学 2011-05-10 Sergei F. Shandarin

We describe and implement an exact, flexible, and computationally efficient algorithm for joint component separation and CMB power spectrum estimation, building on a Gibbs sampling framework. Two essential new features are 1) conditional…

天体物理学 · 物理学 2010-11-11 H. K. Eriksen , J. B. Jewell , C. Dickinson , A. J. Banday , K. M. Gorski , C. R. Lawrence

A maximum-likelihood method is presented for estimating the power spectrum of anisotropies in the cosmic microwave background (CMB) from interferometer observations. The method calculates flat band-power estimates in separate bins in…

天体物理学 · 物理学 2009-11-07 M. P. Hobson , Klaus Maisinger

Band-power estimates of cosmic microwave background fluctuations are now routinely used to place constraints on cosmological parameters. For this to be done in a rigorous fashion, the full likelihood function of band-power estimates must be…

天体物理学 · 物理学 2011-05-23 J. G. Bartlett , M. Douspis , A. Blanchard , M. Le Dour
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