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Related papers: A low CMB variance in the WMAP data

200 papers

We present new full-sky temperature maps in five frequency bands from 23 to 94 GHz, based on the first three years of the WMAP sky survey. The new maps, which are consistent with the first-year maps and more sensitive, incorporate…

We perform a blind multi-component analysis of the WMAP 1 year foreground cleaned maps using SMICA (Spectral Matching Independent Component Analysis). We provide a new estimate of the CMB power spectrum as well as the amplitude of the CMB…

Astrophysics · Physics 2009-11-10 G. Patanchon , J. -F. Cardoso , J. Delabrouille , P. Vielva

Accurate measurements of the cosmic microwave background (CMB) anisotropies with an angular resolution of a few arcminutes can be used to determine fundamental cosmological parameters such as the densities of baryons, cold and hot dark…

Astrophysics · Physics 2016-01-13 J. Richard Bond , George Efstathiou , Max Tegmark

Several accurate analyses of the CMB temperature maps from the Wilkinson Microwave Anisotropy Probe (WMAP) have revealed a set of anomalous results, at large angular scales, that appears inconsistent with the statistical isotropy expected…

Astrophysics · Physics 2009-07-22 A. Bernui , W. S. Hipolito-Ricaldi

Estimation of the angular power spectrum is one of the important steps in Cosmic Microwave Background (CMB) data analysis. Here, we present a nonparametric estimate of the temperature angular power spectrum for the Planck 2013 CMB data. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Amir Aghamousa , Arman Shafieloo , Mihir Arjunwadkar , Tarun Souradeep

We study constraints on time variation of the fine structure constant alpha from cosmic microwave background (CMB) taking into account simultaneous change in alpha and the electron mass m_e which might be implied in unification theories. We…

Astrophysics · Physics 2008-11-26 Kazuhide Ichikawa , Toru Kanzaki , Masahiro Kawasaki

The statistical expectation values of the temperature fluctuations and polarization of cosmic microwave background (CMB) are assumed to be preserved under rotations of the sky. We investigate the statistical isotropy (SI) of the CMB maps…

Astrophysics · Physics 2009-11-11 Tarun Souradeep , Amir Hajian , Soumen Basak

Upcoming surveys will measure the cosmic microwave background (CMB) weak lensing power spectrum in exquisite detail, allowing for strong constraints on the sum of neutrino masses among other cosmological parameters. Standard CMB lensing…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-23 Delon Shen , Emmanuel Schaan , Simone Ferraro

[Abridged] In this paper we explore a local non-linear perturbative model up to third order as a general characterization of the CMB anisotropies. We focus our analysis in large scale anisotropies. At these angular scales, the non-Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 P. Vielva , J. L. Sanz

The current enthusiam to measure fluctuations in the CMB power spectrum at angular scales between 0.1 and 1 degree is largely motivated by the expectation that CMB determinations of cosmological parameters will be of unprecedented…

Astrophysics · Physics 2007-05-23 C. H. Lineweaver

We introduce a new CMB temperature likelihood approximation called the Gaussianized Blackwell-Rao (GBR) estimator. This estimator is derived by transforming the observed marginal power spectrum distributions obtained by the CMB Gibbs…

Astrophysics · Physics 2011-02-11 Ø. Rudjord , N. E. Groeneboom , H. K. Eriksen , Greg Huey , K. M. Górski , J. B. Jewell

An unexpected distribution of temperatures in the CMB could be a sign of new physics. In particular, the existence of cosmic defects could be indicated by temperature discontinuities via the Kaiser-Stebbins effect. In this paper, we show…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Jude Bowyer , Andrew H. Jaffe

In this paper, we explore the power of the cosmic microwave background (CMB) polarization (E-mode) data to corroborate four potential anomalies in CMB temperature data: the lack of large angular-scale correlations, the alignment of the…

The Cosmic Microwave Background (CMB) anisotropy power on the largest angular scales observed both by WMAP and COBE DMR appears to be lower than the one predicted by the standard model of cosmology with almost scale free primordial…

Astrophysics · Physics 2009-09-29 Carlo R. Contaldi , Marco Peloso , Lev Kofman , Andrei Linde

We study the angular distribution of temperature fluctuations in the cosmic microwave background (CMB) to probe the statistical isotropy of the universe by using precise full-sky CMB data with a model-independent approach. We investigated…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-01 C. E. Kester , A. Bernui , W. S. Hipólito-Ricaldi

While the observed nearly scale-invariant initial power spectrum is regarded as one of the favorable evidence of the standard inflationary cosmology, precision observations of the Cosmic Microwave Background (CMB) anisotropies also suggest…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-06 Koichiro Horiguchi , Kiyotomo Ichiki , Jun'ichi Yokoyama

The detection of non-Gaussianity in the CMB data would rule out a number of inflationary models. A null detection of non-Gaussianity, instead, would exclude alternative models for the early universe. Thus, a detection or non-detection of…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-15 A. Bernui , M. J. Rebouças , A. F. F. Teixeira

The success of precision cosmology depends not only on accurate observations, but also on the theoretical model - which must be understood to at least the same level of precision. Subtle relativistic effects can lead to biased measurements…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Chris Clarkson , Obinna Umeh , Roy Maartens , Ruth Durrer

An intriguing discrepancy emerging in the concordance model of cosmology is the tension between the locally measured value of the Hubble rate, and the 'global' value inferred from the cosmic microwave background (CMB). This could be due to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Vinicius C. Busti , Chris Clarkson , Marina Seikel

We review the present status of Cosmic Microwave Background (CMB) anisotropy observations and discuss the main related astrophysical issues, instrumental effects and data analysis techniques. We summarise the balloon-borne and ground-based…

Astrophysics · Physics 2007-05-23 M. Bersanelli , D. Maino , A. Mennella