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Related papers: Examining statistical isotropy of CMB low multipol…

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We develop the XFaster Cosmic Microwave Background (CMB) temperature and polarization anisotropy power spectrum and likelihood technique for the Planck CMB satellite mission. We give an overview of this estimator and its current…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 G. Rocha , C. R. Contaldi , J. R. Bond , K. M. Gorski

The temperature fluctuations of the Cosmic Microwave Background (CMB) are supposed to be distributed randomly in both magnitude and phase, following to the simplest model of inflation. In this paper, we look at the odd and even multipoles…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 M. Hansen , A. M. Frejsel , J. Kim , P. Naselsky , F. Nesti

The largest temperature anisotropy in the cosmic microwave background (CMB) is the dipole. The simplest interpretation of the dipole is that it is due to our motion with respect to the rest frame of the CMB. As well as creating the $\ell$=1…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-25 Raelyn M. Sullivan , Douglas Scott

We apply the Gabor transform methodology proposed in (Hansen et al. 2002, 2003) to the WMAP data in order to test the statistical properties of the CMB fluctuation field and specifically to evaluate the fundamental assumption of…

Astrophysics · Physics 2009-05-29 F. K. Hansen , A. J. Banday , K. M. Gorski

ABRIDGED: We introduce and analyze a method for testing statistical isotropy and Gaussianity and apply it to the WMAP CMB foreground reduced, temperature maps, and cross-channel difference maps. We divide the sky into regions of varying…

Astrophysics · Physics 2009-06-23 Bartosz Lew

We present the temperature and polarization angular power spectra of the cosmic microwave background (CMB) derived from the first 5 years of WMAP data. The 5-year temperature (TT) spectrum is cosmic variance limited up to multipole l=530,…

The statistics of the temperature anisotropies in the primordial cosmic microwave background radiation field provide a wealth of information for cosmology and for estimating cosmological parameters. An even more acute inference should stem…

Instrumentation and Methods for Astrophysics · Physics 2009-11-13 J. L. Starck , Y. Moudden , J. Bobin

We discuss how an extended foreground of the cosmic microwave background (CMB) can account for the anomalies in the low multipoles of the CMB anisotropies. The distortion needed to account for the anomalies is consistent with a cold spot…

Astrophysics · Physics 2009-11-11 L. Raul Abramo , Laerte Sodre , Carlos Alexandre Wuensche

The most general homogeneous and isotropic statistical ensemble of linear scalar perturbations which are regular at early times, in a universe with only photons, baryons, neutrinos, and a cold dark matter (CDM) component, is described by a…

Astrophysics · Physics 2009-10-31 Martin Bucher , Kavilan Moodley , Neil Turok

Recently, it was shown that local variance maps of temperature anisotropy are simple and useful tools for the study of large scale hemispherical power asymmetry. This was done by studying the distribution of dipoles of the local variance…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-12 Saroj Adhikari

The cosmic microwave background (CMB) contains perturbations that are close to Gaussian and isotropic. This means that its information content, in the sense of the ability to constrain cosmological models, is closely related to the number…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-06 Douglas Scott , Dagoberto Contreras , Ali Narimani , Yin-Zhe Ma

Large-scale modes in the temperature anisotropy power spectrum C_l measured by the Wilkinson Microwave Anisotropy Probe (WMAP), seem to have lower amplitudes (C_2, C_3 and C_4) than that expected in the so called concordance LCDM model. In…

Astrophysics · Physics 2009-11-07 E. Gaztanaga , J. Wagg , T. Multamaki , A. Montana , D. H. Hughes

The cosmic microwave background (CMB) temperature maps from the Wilkinson Microwave Anisotropy Probe (WMAP) are of great importance for cosmology. In previous work we had developed a pipeline for map-making independently of the WMAP team.…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-23 Hao Liu , Shao-Lin Xiong , Ti-Pei Li

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

The Wilkinson Microwave Anisotropy Probe (WMAP) has measured lower amplitudes for the temperature quadrupole and octopole anisotropies than expected in the best fitting (concordance) Lambda-dominated cold dark matter cosmology. Some authors…

Astrophysics · Physics 2009-11-10 G. Efstathiou

The statistical properties of the temperature anisotropies and polarization of the of cosmic microwave background (CMB) radiation offer a powerful probe of the physics of the early universe. In recent works a statistical procedure based…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-15 M. J. Reboucas , A. Bernui

Diffusion damping of the cosmic microwave background (CMB) power spectrum results from imperfect photon-baryon coupling in the pre-recombination plasma. At redshift $5 \times 10^4 < z < 2 \times 10^6$, the plasma acquires an effective…

We consider the possibility that the primordial curvature perturbation is direction-dependent. To first order this is parameterised by a quadrupolar modulation of the power spectrum and results in statistical anisotropy of the CMB, which…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-15 Amel Durakovic , Paul Hunt , Suvodip Mukherjee , Subir Sarkar , Tarun Souradeep

Since WMAP and Planck some anomalous features appeared in the Cosmic Microwave Background (CMB) large-angle anisotropy, the so-called anomalies. One of these is the hemispherical power asymmetry, i.e. a difference in the average power on…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-06 Giacomo Galloni , Nicola Bartolo , Sabino Matarrese , Marina Migliaccio , Angelo Ricciardone , Nicola Vittorio

The precise measurements of Cosmic Microwave Background Anisotropy angular power spectra made by the Planck satellite show an anomalous value for the lensing amplitude, defined by the parameter $A_{lens}$, at more than $2$ standard…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-17 Fabrizio Renzi , Eleonora Di Valentino , Alessandro Melchiorri