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We improve the algorithm of Kosowsky, Milosavljevic, and Jimenez (2002) for computing power spectra of the cosmic microwave background. The present algorithm computes not only the temperature power spectrum but also the E-mode polarization…

天体物理学 · 物理学 2009-11-10 Raul Jimenez , Licia Verde , Hiranya Peiris , Arthur Kosowsky

There is enormous potential to advance cosmology from statistical characterizations of cosmic microwave background sky maps. The angular power spectrum of the microwave anisotropy is a particularly important statistic. Existing algorithms…

天体物理学 · 物理学 2009-10-30 Siang Peng Oh , David N. Spergel , Gary Hinshaw

We have developed a fast method for predicting the angular power spectrum, C_l, of the cosmic microwave background given cosmological parameters and a primordial power spectrum of perturbations. After pre--computing the radiation…

天体物理学 · 物理学 2009-11-07 Manoj Kaplinghat , Lloyd Knox , Constantinos Skordis

We present a fast method for estimating the cosmic microwave background polarization power spectra using unbiased estimates of heuristically-weighted correlation functions. This extends the O(N_pix^(3/2)) method of Szapudi et al. (2001) to…

天体物理学 · 物理学 2009-11-07 Gayoung Chon , Anthony Challinor , Simon Prunet , Eric Hivon , Istvan Szapudi

We revisit the issue of cosmological parameter estimation in light of current and upcoming high-precision measurements of the cosmic microwave background power spectrum. Physical quantities which determine the power spectrum are reviewed,…

天体物理学 · 物理学 2009-11-07 Arthur Kosowsky , Milos Milosavljevic , Raul Jimenez

Accurate covariance matrices are required for a reliable estimation of cosmological parameters from pseudo-power spectrum estimators. In this work, we focus on the analytical calculation of covariance matrices. We consider the case of…

宇宙学与河外天体物理 · 物理学 2022-12-08 Étienne Camphuis , Karim Benabed , Silvia Galli , Éric Hivon , Marc Lilley

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…

天体物理学 · 物理学 2011-08-11 E. Hivon , K. M. Gorski , C. B. Netterfield , B. P. Crill , S. Prunet , F. Hansen

Extraction of the CMB (Cosmic Microwave Background) angular power spectrum is a challenging task for current and future CMB experiments due to the large data sets involved. Here we describe an implementation of MASTER (Monte carlo Apodised…

天体物理学 · 物理学 2009-11-10 T. Poutanen , D. Maino , H. Kurki-Suonio , E. Keihanen , E. Hivon

Estimation of the angular power spectrum of the Cosmic Microwave Background (CMB) on a small patch of sky is usually plagued by serious spectral leakage, specially when the map has a hard edge. Even on a full sky map, point source masks can…

天体物理学 · 物理学 2009-11-06 Sudeep Das , Amir Hajian , David N. Spergel

In this paper, we focus our attention on the following question: How well can we recover the power spectrum of the cosmic microwave background from the maps of a given experiment?. Each experiment is described by a a pixelization scale, a…

天体物理学 · 物理学 2016-08-15 D. Sáez , J. V. Arnau

We explore the low-l likelihood of the angular spectrum C(l) of masked CMB temperature maps using an adaptive importance sampler. We find that, in spite of a partial sky coverage, the likelihood distribution of each C(l) closely follows an…

宇宙学与河外天体物理 · 物理学 2015-05-13 K. Benabed , J. -F. Cardoso , S. Prunet , E. Hivon

Angular power spectrum of the cosmic microwave background (CMB) temperature anisotropies is one of the most important on characteristics of the Universe such as its geometry and total density. Using flat sky approximation and Fourier…

宇宙学与河外天体物理 · 物理学 2015-05-30 Lung-Yih Chiang , Fei-Fan Chen

The widely used MASTER approach for angular power spectrum estimation was developed as a fast $C_{\ell}$ estimator on limited regions of the sky. This method expresses the power spectrum of a masked map ("pseudo-$C_\ell$") in terms of the…

宇宙学与河外天体物理 · 物理学 2023-04-27 Kristen M. Surrao , Oliver H. E. Philcox , J. Colin Hill

We develop a set of machine-learning based cosmological emulators, to obtain fast model predictions for the $C(\ell)$ angular power spectrum coefficients characterising tomographic observations of galaxy clustering and weak gravitational…

宇宙学与河外天体物理 · 物理学 2022-06-30 Marco Bonici , Luca Biggio , Carmelita Carbone , Luigi Guzzo

We describe an algorithm for the extraction of the angular power spectrum of an intensity field, such as the cosmic microwave background (CMB), from interferometer data. This new method, based on the gridding of interferometer visibilities…

High-resolution Maximum Likelihood map-making of the Cosmic Microwave Background is usually performed using Conjugate Gradients with a preconditioner that ignores noise correlations. We here present a new preconditioner that approximates…

天体物理仪器与方法 · 物理学 2015-06-17 Sigurd Næss , Thibaut Louis

The Fisher information matrix of the cosmic microwave background (CMB) radiation power spectrum coefficients is a fundamental quantity that specifies the information content of a CMB experiment. In the most general case, its exact…

宇宙学与河外天体物理 · 物理学 2012-03-30 Franz Elsner , Benjamin D. Wandelt

The confrontation of the Cosmic Microwave Background (CMB) theoretical angular power spectrum with available data often requires the calculation of large numbers of power spectra. The standard practice is to use a fast code to compute the…

天体物理学 · 物理学 2009-10-31 Kris Sigurdson , Douglas Scott

Empirical estimates of the band power covariance matrix are commonly used in cosmic microwave background (CMB) power spectrum analyses. While this approach easily captures correlations in the data, noise in the resulting covariance estimate…

宇宙学与河外天体物理 · 物理学 2022-03-14 L. Balkenhol , C. L. Reichardt
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