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相关论文: A comparison of CMB Angular Power Spectrum Estimat…

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We use a Quadratic Maximum Likelihood (QML) method to estimate the angular power spectrum of the cross-correlation between cosmic microwave background and large scale structure maps as well as their individual auto-spectra. We describe our…

宇宙学与河外天体物理 · 物理学 2015-06-04 F. Schiavon , F. Finelli , A. Gruppuso , A. Marcos-Caballero , P. Vielva , R. G. Crittenden , R. B. Barreiro , E. Martinez-Gonzalez

Estimating the cross-correlation power spectra of cosmic microwave background (CMB), in particular, the T B and EB spectra, is important for testing parity symmetry in cosmology and diagnosing insidious instruments systematics. The…

天体物理仪器与方法 · 物理学 2022-06-29 Jiming Chen , Shamik Ghosh , Wen Zhao

A Quadratic Maximum Likelihood (QML) estimator is applied to the WMAP 5 year low resolution maps to compute the CMB angular power spectra at large scales for both temperature and polarization. Estimates and error bars for the six angular…

宇宙学与河外天体物理 · 物理学 2010-11-02 A. Gruppuso , A. De Rosa , P. Cabella , F. Paci , F. Finelli , P. Natoli , G. de Gasperis , N. Mandolesi

Fast robust methods for calculating likelihoods from CMB observations on small scales generally rely on approximations based on a set of power spectrum estimators and their covariances. We investigate the optimality of these approximation,…

宇宙学与河外天体物理 · 物理学 2009-11-06 Samira Hamimeche , Antony Lewis

It is widely believed that maximum likelihood estimators must be used to provide optimal estimates of power spectra. Since such estimators require require of order N_d^3 operations they are computationally prohibitive for N_d greater than a…

天体物理学 · 物理学 2008-11-26 G. Efstathiou

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

We use quadratic maximum-likelihood (QML) estimators to constrain models with Gaussian but statistically anisotropic Cosmic Microwave Background (CMB) fluctuations, using CMB maps with realistic sky-coverage and instrumental noise. This…

宇宙学与河外天体物理 · 物理学 2012-03-06 Duncan Hanson , Antony Lewis

We develop two methods for estimating the power spectrum, C_l, of the cosmic microwave background (CMB) from data and apply them to the COBE/DMR and Saskatoon datasets. One method involves a direct evaluation of the likelihood function, and…

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

Constructing a fast and efficient estimator for the B-mode power spectrum of cosmic microwave background (CMB) is of critical importance for CMB science. For a general CMB survey, the Quadratic Maximum Likelihood (QML) estimator for CMB…

宇宙学与河外天体物理 · 物理学 2021-11-17 Jiming Chen , Shamik Ghosh , Hao Liu , Larissa Santos , Wenjuan Fang , Siyu Li , Yang Liu , Hong Li , Jiaxin Wang , Le Zhang , Bin Hu , Wen Zhao

A new method for estimating the angular power spectrum C_l from cosmic microwave background (CMB) maps is presented, which has the following desirable properties: (1) It is unbeatable in the sense that no other method can measure C_l with…

天体物理学 · 物理学 2009-10-07 Max Tegmark

Strong foreground contamination in high resolution CMB data requires masking which introduces statistical anisotropies and renders a full maximum likelihood analysis numerically intractable. Standard analysis methods like the pseudo-C_l…

宇宙学与河外天体物理 · 物理学 2014-03-26 H. F. Gruetjen , E. P. S. Shellard

We revisit the problem of exact CMB likelihood and power spectrum estimation with the goal of minimizing computational cost through linear compression. This idea was originally proposed for CMB purposes by Tegmark et al.\ (1997), and here…

天体物理仪器与方法 · 物理学 2015-11-18 E. Gjerløw , L. P. L. Colombo , H. K. Eriksen , K. M. Górski , A. Gruppuso , J. B. Jewell , S. Plaszczynski , I. K. Wehus

The Quadratic Maximum Likelihood estimator can be used to reconstruct the Cosmic Microwave Background (CMB) power spectra with minimal error bars. Still, it requires an accurate estimate of the datasets noise covariance matrix in order to…

宇宙学与河外天体物理 · 物理学 2018-11-28 S. Vanneste , S. Henrot-Versillé , T. Louis , M. Tristram

The amplitudes of the quadrupole and octopole measured from the Wilkinson Microwave Anisotropy Probe (WMAP) appear to be lower than expected according to the concordance Lambda CDM cosmology. However, the pseudo-Cl estimator used by the…

天体物理学 · 物理学 2009-07-09 G. Efstathiou

We develop the pseudo-Cl method for reconstructing the Cosmic Microwave Background (CMB) temperature and polarization auto- and cross-power spectra, and estimate the pseudo-Cl covariance matrix for a realistic experiment on the cut sky. We…

天体物理学 · 物理学 2009-11-10 M. L. Brown , P. G. Castro , A. N. Taylor

We present two novel methods for the estimation of the angular power spectrum of cosmic microwave background (CMB) anisotropies. We assume an absolute CMB experiment with arbitrary asymmetric beams and arbitrary sky coverage. The methods…

宇宙学与河外天体物理 · 物理学 2017-01-25 Elina Keihänen , Kimmo Kiiveri , Hannu Kurki-Suonio , Martin Reinecke

We present ECLIPSE (Efficient Cmb poLarization and Intensity Power Spectra Estimator), an optimized implementation of the Quadratic Maximum Likelihood (QML) method for the estimation of the power spectra of the Cosmic Microwave Background…

宇宙学与河外天体物理 · 物理学 2021-08-02 J. D. Bilbao-Ahedo , R. B. Barreiro , P. Vielva , E. Martínez-González , D. Herranz

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.…

天体物理学 · 物理学 2011-08-01 G. Faÿ , F. Guilloux , M. Betoule , J. -F. Cardoso , J. Delabrouille , M. Le Jeune

Over the last decade, measurements of the CMB anisotropy has spearheaded the remarkable transition of cosmology into a precision science. However, addressing the systematic effects in the increasingly sensitive, high resolution, `full' sky…

天体物理学 · 物理学 2009-03-31 Sanjit Mitra , Anand S. Sengupta , Subharthi Ray , Rajib Saha , Tarun Souradeep

In the era of high precision CMB measurements, systematic effects are beginning to limit the ability to extract subtler cosmological information. The non-circularity of the experimental beam has become progressively important as CMB…

天体物理学 · 物理学 2011-04-11 Tarun Souradeep , Sanjit Mitra , Anand Sengupta , Subharthi Ray , Rajib Saha
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