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相关论文: Large-scale power in the CMB and new physics: an a…

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The recent WMAP data represents a milestone in cosmology and helps constrain cosmological parameters with unprecedented accuracy. In this work we combine the WMAP data with previous CMB anisotropy measurements at smaller angular scales to…

天体物理学 · 物理学 2015-06-24 C. J. Odman

We use recent results from the Wilkinson Microwave Anisotropy Probe (WMAP) for the locations of peaks and troughs of the Cosmic Microwave Background (CMB) power spectrum, together with constraints from large-scale structure, to study a…

天体物理学 · 物理学 2009-11-07 T. Barreiro , M. C. Bento , N. M. C. Santos , A. A. Sen

We present the first results from a Bayesian analysis of the WMAP first year data using a Gibbs sampling technique. Using two independent, parallel supercomputer codes we analyze the WMAP Q, V and W bands. The analysis results in a full…

We analyze the three-year WMAP temperature anisotropy data seeking to confirm the power spectrum and likelihoods published by the WMAP team. We apply five independent implementations of four algorithms to the power spectrum estimation and…

CMB mapmaking relies on a data model to solve for the sky map, and this process is vulnerable to bias if the data model cannot capture the full behavior of the signal. We demonstrate that this bias is not just limited to small-scale effects…

天体物理仪器与方法 · 物理学 2024-08-30 Sigurd Naess , Thibaut Louis

Several anomalies appear to be present in the large-angle cosmic microwave background (CMB) anisotropy maps of WMAP. One of these is a lack of large-scale power. Because the data otherwise match standard models extremely well, it is natural…

天体物理学 · 物理学 2008-12-18 Emory F. Bunn , Austin Bourdon

We first discuss the sensitivity of the WMAP CMB power spectrum to systematic errors by calculating the raw CMB power spectrum from WMAP data. We find that the power spectrum is surprisingly sensitive to the WMAP radiometer beam profile…

宇宙学与河外天体物理 · 物理学 2010-06-08 Utane Sawangwit , Tom Shanks

The Cosmic Microwave Background (CMB) power spectrum derived from the first year WMAP data demonstrates an intriguing lack of power at large scales that cannot be accounted for within the framework of the standard cosmological model. We…

天体物理学 · 物理学 2009-11-11 Anastasia Niarchou , Andrew H. Jaffe

We use the results from the Wilkinson Microwave Anisotropy Probe (WMAP) for the locations of peaks and troughs of the Cosmic Microwave Background (CMB) power spectrum, together with constraints from large-scale structure, to study a…

天体物理学 · 物理学 2016-11-09 T. Barreiro , M. C. Bento , N. M . C. Santos , A. A. Sen

The cold dark matter (CDM) model of structure formation, normalized on large scales, leads to excessive pairwise velocity dispersions on small scales. In an attempt to circumvent this problem, we study three scenarios (all with $\Omega=1$)…

高能物理 - 唯象学 · 物理学 2009-10-22 James. M. Gelb , Ben-Ami Gradwohl , Joshua A. Frieman

The cosmic microwave background (CMB) temperature distribution measured by the Wilkinson Microwave Anisotropy Probe (WMAP) exhibits anomalously low correlation at large angles. Quantifying the degree to which this feature in the temperature…

宇宙学与河外天体物理 · 物理学 2015-05-30 Andrew P. Hearin , Cameron Gibelyou , Andrew R. Zentner

We present a Bayesian analysis of large-scale structure and cosmic microwave background data to constrain the form of the primordial power spectrum. We have extended the usual presumption of a scale invariant spectrum to include: (i) a…

天体物理学 · 物理学 2009-11-11 M. Bridges , A. N. Lasenby , M. P. Hobson

Using a nonparametric function estimation methodology, we present a comparative analysis of the WMAP 1-, 3-, 5-, and 7-year data releases for the CMB angular power spectrum with respect to the following key questions: (a) How well is the…

宇宙学与河外天体物理 · 物理学 2012-01-10 Amir Aghamousa , Mihir Arjunwadkar , Tarun Souradeep

We have investigated the constraints on the Cardassian model using the recent results from the Wilkinson Microwave Anisotropy Probe (WMAP) for the locations of the peaks of the Cosmic Microwave Background (CMB) anistropy spectrum. We find…

天体物理学 · 物理学 2016-08-30 A. A. Sen , S. Sen

We estimate the amplitude of perturbation in dark energy at different length scales for a quintessence model with an exponential potential. It is shown that on length scales much smaller than hubble radius, perturbation in dark energy is…

天体物理学 · 物理学 2008-12-18 Sanil Unnikrishnan , H. K. Jassal , T. R. Seshadri

In recent years the goal of estimating different cosmological parameters precisely has set new challenges in the effort to accurately measure the angular power spectrum of CMB. This has required removal of foreground contamination as well…

天体物理学 · 物理学 2008-11-26 Rajib Saha , Simon Prunet , Pankaj Jain , Tarun Souradeep

(Abridged)Motivated by the recent results of Hansen et al. (2008) concerning a noticeable hemispherical power asymmetry in the WMAP data on small angular scales, we revisit the dipole modulated signal model introduced by Gordon et al.…

宇宙学与河外天体物理 · 物理学 2011-02-11 J. Hoftuft , H. K. Eriksen , A. J. Banday , K. M. Gorski , F. K. Hansen , P. B. Lilje

The power spectrum of mass density fluctuations is estimated from the Mark III and the SFI catalogs of peculiar velocities by applying a maximum likelihood analysis, using parametric models for the power spectrum and for the errors.…

天体物理学 · 物理学 2007-05-23 Idit Zehavi

We constrain the shape of the primordial power spectrum using recent measurements of the cosmic microwave background (CMB) from the Wilkinson Microwave Anisotropy Probe (WMAP) 7-year data and other high-resolution CMB experiments. We also…

宇宙学与河外天体物理 · 物理学 2012-06-27 J. Alberto Vazquez , A. N. Lasenby , M. Bridges , M. P. Hobson

Suppression in primordial power on the Universe's largest observable scales has been invoked as a possible explanation for large-angle observations in the cosmic microwave background, and is allowed or predicted by some inflationary models.…

宇宙学与河外天体物理 · 物理学 2011-04-04 Cameron Gibelyou , Dragan Huterer , Wenjuan Fang
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