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Asymmetric beams can create significant bias in estimates of the power spectra from CMB experiments. With the temperature power spectrum many orders of magnitude stronger than the B-mode power spectrum any systematic error that couples the…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-08 Christopher G. R. Wallis , Michael L. Brown , Richard A. Battye , Giampaolo Pisano , Luca Lamagna

Several recent papers have made claims about the detection of an asymmetric distribution of large scale power in the cosmic microwave background anisotropy as measured by the WMAP satellite. In this paper, we investigate how the estimates…

Astrophysics · Physics 2009-11-10 F. K. Hansen , A. Balbi , A. J. Banday , K. M. Gorski

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 presence of a dipolar statistical anisotropy in the spectrum of cosmic microwave background (CMB) fluctuations was reported by the Wilkinson Microwave Anisotropy Probe (WMAP), and has recently been confirmed in the Planck 2013 analysis…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-29 Sugumi Kanno , Misao Sasaki , Takahiro Tanaka

One of the most tantalizing results from the WMAP experiment is the suggestion that the power at large scales is anomalously low when compared to the prediction of the ``standard'' Lambda-CDM model. The same anomaly, although with somewhat…

Astrophysics · Physics 2009-11-10 Anastasia Niarchou , Andrew H. Jaffe , Levon Pogosian

The angular power spectrum of the cosmic microwave background temperature anisotropy observed by WMAP has an anomalous dip at l~20 and bump at l~40. One explanation for this structure is the presence of features in the primordial curvature…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-19 Michael J. Mortonson , Cora Dvorkin , Hiranya V. Peiris , Wayne Hu

One of the most intriguing hints of a departure from the standard cosmological model is a large-scale dipolar power asymmetry in the cosmic microwave background (CMB). If not a statistical fluke, its origins must lie in the modulation of…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-23 J. P. Zibin , D. Contreras

A new method for estimating the angular power spectrum C_l from cosmic microwave background (CMB) maps is presented, which has the following desirable properties: (1) It is unbeatable in the sense that no other method can measure C_l with…

Astrophysics · Physics 2009-10-07 Max Tegmark

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

We present limits to the amplitude of non-Gaussian primordial fluctuations in the WMAP 1-year cosmic microwave background sky maps. A non-linear coupling parameter, f_NL, characterizes the amplitude of a quadratic term in the primordial…

We measure the skewness power spectrum of the Cosmic Microwave Background (CMB) anisotropies optimized for a detection of the secondary bispectrum generated by the correlation of the CMB lensing potential with integrated Sachs-Wolfe effect…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 Erminia Calabrese , Joseph Smidt , Alexandre Amblard , Asantha Cooray , Alessandro Melchiorri , Paolo Serra , Alan Heavens , Dipak Munshi

Bianchi VII_h models have been recently proposed to explain potential anomalies in the CMB anisotropy as observed by WMAP. We investigate the violation of statistical isotropy due to an embedded Bianchi VII_h templates in the CMB anisotropy…

Astrophysics · Physics 2008-11-26 Tuhin Ghosh , Amir Hajian , Tarun Souradeep

The connection between the dipolar modulation asymmetry and the quadrupole-octopole alignment in the CMB is studied in this work. First, a generalization of the dipolar modulation model is proposed by considering that the amplitude may…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-06 A. Marcos-Caballero , E. Martínez-González

We introduce a class of models in which statistical isotropy is broken spontaneously in the CMB by a non-linear response to long-wavelength fluctuations in a mediating field. These fluctuations appear as a gradient locally and pick out a…

Astrophysics · Physics 2008-11-26 Christopher Gordon , Wayne Hu , Dragan Huterer , Tom Crawford

The lack of power of large--angle CMB anisotropies is known to increase its statistical significance at higher Galactic latitudes, where a string--inspired pre--inflationary scale $\Delta$ can also be detected. Considering the Planck 2015…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-13 A. Gruppuso , N. Kitazawa , M. Lattanzi , N. Mandolesi , P. Natoli , A. Sagnotti

We present an updated data-analysis comparison of the most recent observations of the Cosmic Microwave Background temperature anisotropies and polarization angular power spectra released by four different experiments: the Planck satellite…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-15 Eleonora Di Valentino , William Giarè , Alessandro Melchiorri , Joseph Silk

We derive the CMB radiative transfer equation in the form of a multipole hierarchy in the nearly-Friedmann-Robertson-Walker limit of homogeneous, but anisotropic, universes classified via their Bianchi type. Compared with previous…

Astrophysics · Physics 2007-09-13 Andrew Pontzen , Anthony Challinor

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…

Astrophysics · Physics 2009-11-07 T. Barreiro , M. C. Bento , N. M. C. Santos , A. A. Sen

In this paper, we present results from the complete set of cosmic microwave background (CMB) radiation temperature anisotropy observations made with the Arcminute Cosmology Bolometer Array Receiver (ACBAR) operating at 150 GHz. We include…

In this work, we study a direction dependent power spectrum in anisotropic Finsler space-time. We use this direction dependent power spectrum to address the low-l power observed in WMAP and PLANCK data. The angular power spectrum of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-04 Zhe Chang , Pranati K. Rath , Yu Sang , Dong Zhao