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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…

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

We present efficient algorithms for CMB lensing simulation and power spectrum es- timation for flat-sky CMB polarization maps. We build a pure B-mode estimator to remedy E to B leakage due to partial sky coverage. We show that our…

宇宙学与河外天体物理 · 物理学 2013-11-14 Thibaut Louis , Sigurd Næss , Sudeep Das , Joanna Dunkley , Blake Sherwin

Accurate estimation of the Cosmic Microwave Background (CMB) angular power spectrum is enticing due to the prospect for precision cosmology it presents. Galactic foreground emissions, however, contaminate the CMB signal and need to be…

宇宙学与河外天体物理 · 物理学 2021-10-04 Pallav Chanda , Rajib Saha

We present a new, fast, algorithm for the separation of astrophysical components superposed in maps of the sky, based on the fast Independent Component Analysis technique (FastICA). It allows to recover both the spatial pattern and the…

Galactic all-sky maps at very disparate frequencies, like in the radio and $\gamma$-ray regime, show similar morphological structures. This mutual information reflects the imprint of the various physical components of the interstellar…

Gravitational lensing distorts the cosmic microwave background (CMB) anisotropies and imprints a characteristic pattern onto it. The distortions depend on the projected matter density between today and redshift $z \sim 1100$. In this paper…

天体物理学 · 物理学 2016-08-25 Matias Zaldarriaga , Uros Seljak

We present a new method for calculating CMB anisotropies in a non-flat Friedmann universe, relying on a very stable algorithm for the calculation of hyperspherical Bessel functions, that can be pushed to arbitrary precision levels. We also…

宇宙学与河外天体物理 · 物理学 2015-06-18 Julien Lesgourgues , Thomas Tram

By actively distorting the Cosmic Microwave Background (CMB) over our past light cone, cosmic strings are unavoidable sources of non-Gaussianity. Developing optimal estimators able to disambiguate a string signal from the primordial type of…

宇宙学与河外天体物理 · 物理学 2012-08-22 Christophe Ringeval , Francois R. Bouchet

We describe the calibration and data processing methods used to generate full-sky maps of the cosmic microwave background (CMB) from the first year of Wilkinson Microwave Anisotropy Probe (WMAP) observations. Detailed limits on residual…

Cosmic Microwave Background (CMB) has been a cornerstone in many cosmology experiments and studies since it was discovered back in 1964. Traditional computational models like CAMB that are used for generating CMB temperature anisotropy maps…

宇宙学与河外天体物理 · 物理学 2019-12-02 Amit Mishra , Pranath Reddy , Rahul Nigam

We discuss in some details a novel algorithm for performing partial-sky spherical harmonic transforms (SHT), building on the Fourier-sphere method of Reinecke et al (2023) handling efficiently high numbers of arbitrary locations on the…

宇宙学与河外天体物理 · 物理学 2026-03-20 Julien Carron , Martin Reinecke

We present a multi-level solver for drawing constrained Gaussian realizations or finding the maximum likelihood estimate of the CMB sky, given noisy sky maps with partial sky coverage. The method converges substantially faster than existing…

天体物理仪器与方法 · 物理学 2014-02-26 D. S. Seljebotn , K. -A. Mardal , J. B. Jewell , H. K. Eriksen , P. Bull

We have simulated full-sky maps of the Cosmic Microwave Background (CMB) anisotropy expected from Cold Dark Matter (CDM) models at 0.5 and 1.0 degree angular resolution. Statistical properties of the maps are presented as a function of sky…

天体物理学 · 物理学 2007-05-23 G. Hinshaw , C. L. Bennett , A. Kogut

The WMAP satellite has made available high quality maps of the sky in five frequency bands ranging from 22 to 94 GHz, with the main scientific objective of studying the anisotropies of the Cosmic Microwave Background (CMB). These maps,…

天体物理学 · 物理学 2009-11-13 J. Delabrouille , J. -F. Cardoso , M. Le Jeune , M. Betoule , G. Fay , F. Guilloux

A major goal of cosmology is to obtain sensitive, high resolution maps of the Cosmic Microwave Background (CMB) anisotropy. Such maps, as would be produced by the recently proposed Microwave Anisotropy Probe (MAP), will contain a wealth of…

天体物理学 · 物理学 2009-10-28 Edward L. Wright , Gary Hinshaw , Charles L. Bennett

For nonlinear multispectral computed tomography (CT), accurate and fast image reconstruction is challenging when the scanning geometries under different X-ray energy spectra are inconsistent or mismatched. Motivated by this, we propose an…

数值分析 · 数学 2025-07-28 Yu Gao , Chong Chen

We present algorithms for searching for azimuthally symmetric features in CMB data. Our algorithms are fully optimal for masked all-sky data with inhomogeneous noise, computationally fast, simple to implement, and make no approximations. We…

宇宙学与河外天体物理 · 物理学 2015-06-15 Stephen Osborne , Leonardo Senatore , Kendrick Smith

We present a fast, arbitrarily accurate method to simulate the effect of gravitational lensing of the Cosmic Microwave Background anisotropies and polarization fields by large scale structures. We demonstrate the efficiency and accuracy of…

天体物理学 · 物理学 2008-11-12 S. Basak , S. Prunet , K. Benabed

Large-scale skymapping with COMPTEL using the full survey database presents challenging problems on account of the complex response and time-variable background. A new approach which attempts to address some of these problems is described,…

天体物理学 · 物理学 2007-05-23 A. W. Strong , H. Bloemen , R. Diehl , W. Hermsen , V. Schoenfelder

Forthcoming high-resolution observations of the Cosmic Microwave Background (CMB) radiation will generate datasets many orders of magnitude larger than have been obtained to date. The size and complexity of such datasets presents a very…

天体物理学 · 物理学 2016-08-25 Julian Borrill