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相关论文: Best Unbiased Estimates for the Microwave Backgrou…

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We present a technique of calculating microwave anisotropies from global defects in a reionised universe. We concentrate on angular scales down to one degree where we expect the nongaussianity of the temperature anisotropy in these models…

天体物理学 · 物理学 2007-05-23 David Coulson

In this talk, I review some recent work on cosmic microwave background (CMB) anisotropies in an open universe. I emphasize that the observed CMB anisotropies are still consistent with a low value of $\Omega$, and I address the question of…

天体物理学 · 物理学 2007-05-23 Marc Kamionkowski

Cosmic microwave background (CMB) anisotropy may result from both scalar and tensor perturbations. For a sufficiently narrow range of angular scales, CMB perturbations can be characterized by four parameters. Results from the Cosmic…

天体物理学 · 物理学 2009-10-22 Scott Dodelson , Lloyd Knox , Edward W. Kolb

We present a formalism for analyzing interferometric observations of Cosmic Microwave Background (CMB) anisotropy and polarization data. The formalism is based upon the ell-space expansion of the angular power spectrum favoured in recent…

天体物理学 · 物理学 2009-08-18 Martin White , John E. Carlstrom , Mark Dragovan , William L. Holzapfel

The Wavelength-Oriented Microwave Background Analysis Team (WOMBAT) is constructing microwave maps which will be more realistic than previous simulations. Our foreground models represent a considerable improvement: where spatial templates…

We aim to present a tutorial on the detection, parameter estimation and statistical analysis of compact sources (far galaxies, galaxy clusters and Galactic dense emission regions) in cosmic microwave background observations. The topic is of…

宇宙学与河外天体物理 · 物理学 2011-01-05 D. Herranz , P. Vielva

We discuss an approach to the component separation of microwave, multi-frequency sky maps as those typically produced from Cosmic Microwave Background (CMB) Anisotropy data sets. The algorithm is based on the two step, parametric,…

天体物理学 · 物理学 2009-06-23 R. Stompor , S. Leach , F. Stivoli , C. Baccigalupi

The cosmic microwave background (CMB) traveled the cosmos long before it reached our telescopes today. Consequently, it is one of the best probes of fundamental processes in the early Universe that we could hope to observe. The cosmological…

宇宙学与河外天体物理 · 物理学 2025-02-11 Jens Chluba

We test the hypothesis that the temperature of the cosmic microwave background is consistent with a Gaussian random field defined on the celestial sphere, using de-biased internal linear combination (DILC) map produced from the 3-year WMAP…

天体物理学 · 物理学 2010-11-11 Lung-Yih Chiang , Pavel D. Naselsky , Peter Coles

We present a strategy for a statistically rigorous Bayesian approach to the problem of determining cosmological parameters from the results of observations of anisotropies in the cosmic microwave radiation background. We propose the…

天体物理学 · 物理学 2007-05-23 Nelson Christensen , Renate Meyer

I report on recent developments in the theory of cosmic background radiation perturbations. I describe ways of modeling alternatives to the canonical Gaussian theories within the standard framework of cosmological perturbation theory. Some…

天体物理学 · 物理学 2016-08-30 Pedro G. Ferreira

A number of experiments for measuring anisotropies of the Cosmic Microwave Background use scanning strategies in which temperature fluctuations are measured along circular scans on the sky. It is possible, from a large number of such…

天体物理学 · 物理学 2009-10-30 J. Delabrouille , K. M. Górski , E. Hivon

As the data on CMB anisotropies improve and potential cosmological applications are realized, it will be increasingly important for theoretical calculations to be as accurate as possible. All modern calculations for inflationary-inspired…

天体物理学 · 物理学 2008-11-26 Wayne Hu , Douglas Scott , Naoshi Sugiyama , Martin White

Using an approximate likelihood method adapted to band--power estimates, we analyze the ensemble of first generation cosmic microwave background anisotropy experiments to deduce constraints over a six--dimensional parameter space describing…

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

Separating foregrounds from the signal is one of the big challenges in cosmic microwave background (CMB) experiments. A simple way to estimate the CMB temperature in a given pixel is to fit for the amplitudes of the CMB and the various…

天体物理学 · 物理学 2009-10-28 Scott Dodelson

The Cosmic Microwave Background (CMB), which permeates the entire Universe, is the radiation left over from just 380,000 years after the Big Bang. On very large scales, the CMB radiation field is smooth and isotropic, but the existence of…

Fluctuations in the cosmic microwave background (CMB) temperature are being studied with ever increasing precision. Two competing types of theories might describe the origins of these fluctuations: ``inflation'' and ``defects''. Here we…

天体物理学 · 物理学 2010-04-08 Andreas Albrecht , David Coulson , Pedro Ferreira , Joao Magueijo

In this paper, we expand the theory of depth-unbiased source localization to unbiased parameter estimation and signal reconstruction of an arbitrary number of non-zero parameters to be recovered. The topic touches on the concept of exact…

信息论 · 计算机科学 2026-05-08 Joonas Lahtinen

We present a new, fully covariant and manifestly gauge-invariant expression for the temperature anisotropy in the cosmic microwave background radiation resulting from scalar perturbations. We pay particular attention to gauge issues such as…

天体物理学 · 物理学 2009-12-30 A. D. Challinor , A. N. Lasenby

Variations in $\Omega$, the total density of the Universe, leave a clear and distinctive imprint on the power spectrum of temperature fluctuations in the cosmic microwave background (CMB). This signature is virtually independent of other…

天体物理学 · 物理学 2009-10-28 Gerard Jungman , Marc Kamionkowski , Arthur Kosowsky , David N. Spergel