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We scrutinize the reported lensing anomaly of the CMB by considering several phenomenological modifications of the lensing consistency parameter, $A_{\rm L}$. Considering Planck spectra alone, we find statisically significant evidence for…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-23 Ido Ben-Dayan , Utkarsh Kumar , Meir Shimon , Amresh Verma

The scattering of cosmic microwave background (CMB) radiation in galaxy clusters induces polarization signals according to the quadrupole anisotropy in the photon distribution at the cluster location. This `remote quadrupole' derived from…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-23 Kiyotomo Ichiki , Kento Sumiya , Guo-Chin Liu

Using the formalism of spin-weighted functions we present an all-sky analysis of polarization in the Cosmic Microwave Background (CMB). Linear polarization is a second-rank symmetric and traceless tensor, which can be decomposed on a sphere…

Astrophysics · Physics 2009-10-28 Matias Zaldarriaga , Uros Seljak

We investigate the hemispherical power asymmetry in the cosmic microwave background on small angular scales. We find an anomalously high asymmetry in the multipole range l=601-2048, with a naive statistical significance of 6.5 sigma.…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-30 Samuel Flender , Shaun Hotchkiss

The characterisation of CMB polarisation is one of the next challenge in observationnal cosmology. This is especially true for the so-called B-modes that are at least 3 order of magnitude lower than CMB temperature fluctuations. A precise…

Astrophysics · Physics 2007-05-23 M. Piat , C. Rosset , the BRAIN , CLOVER Collaboration

Estimates of inflationary parameters from the CMB B-mode polarization spectrum on the largest scales depend on knowledge of the reionization history, especially at low tensor-to-scalar ratio. Assuming an incorrect reionization history in…

Astrophysics · Physics 2008-11-26 Michael J. Mortonson , Wayne Hu

We investigate the impact of peculiar velocity effects due to the motion of the solar system relative to the microwave background (CMB) on high resolution CMB experiments. It is well known that on the largest angular scales the combined…

Astrophysics · Physics 2009-11-07 Anthony Challinor , Floor van Leeuwen

The motion of the solar system barycenter with respect to the cosmic microwave background (CMB) induces a very large apparent dipole component into the CMB brightness map at the 3 mK level. In this Letter we discuss another kinematic effect…

Astrophysics · Physics 2009-11-11 Scott Burles , Saul Rappaport

Searches for the imprint of primordial gravitational waves in degree-scale CMB $B$-mode polarisation data must account for significant contamination from gravitational lensing. Fortunately, the lensing effects can be partially removed by…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-12 Antón Baleato Lizancos , Anthony Challinor , Julien Carron

If the primordial bispectrum is sufficiently large then the CMB hemispherical asymmetry may be explained by a large-scale mode of exceptional amplitude which perturbs the zeta two-point function. We extend previous calculations, which were…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-27 Christian T. Byrnes , Donough Regan , David Seery , Ewan R. M. Tarrant

The reconstruction of the CMB lensing potential is based on a Taylor expansion of lensing effects which is known to have poor convergence properties. For lensing of temperature fluctuations, an understanding of the higher order terms in…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Ethan Anderes

The standard theoretical description $\Theta(\hat n)$ of the observed CMB temperature anisotropies is gauge-dependent. It is, however, well known that the gauge mode is limited to the monopole and the higher angular multipoles $\Theta_l$…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-18 Sandra Baumgartner , Jaiyul Yoo

In general relativity gravitational waves propagate at the speed of light, however in alternative theories of gravity that might not be the case. We study the effects of a modified speed of gravity, $c_T^2$, on the B-modes of the Cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-11 Marco Raveri , Carlo Baccigalupi , Alessandra Silvestri , Shuang-Yong Zhou

The Cosmological Principle assumes a statistically isotropic Universe, but the Cosmic Microwave Background (CMB) exhibits some anomalous statistical features, such as the hemispherical power asymmetry, that challenge this core assumption.…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-25 Javier Carrón Duque , Mikel Martin Barandiaran , Joseba Martínez-Arrizabalaga

It is known that in contrast with the E-mode polarization, the B-mode polarization of the Cosmic Microwave Background cannot be generated by the Compton scattering in the case of scalar mode of metric perturbation. However it is possible to…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-29 Rohoollah Mohammadi , Jafar Khodagholizadeh , Mahdi Sadegh , She-Sheng Xue

We simulate Planck observations by adopting a detailed model of the microwave sky including monopole, dipole, anisotropies of the cosmic microwave background (CMB) and galactic and extragalactic foregrounds. We estimate the impact of main…

We compute the secondary CMBR anisotropy signal from the reionization of the universe in the presence of tangled magnetic fields. We consider the tangled magnetic-field-induced scalar, vector, and tensor modes for our analysis. The most…

Astrophysics · Physics 2008-11-26 Rajesh Gopal , Shiv K. Sethi

We compute the imprints left on the CMB by two cosmic reionization models consistent with current observations but characterized by alternative radiative feedback prescriptions (suppression and filtering) resulting in a different…

Astrophysics · Physics 2015-05-13 C. Burigana , L. A. Popa , R. Salvaterra , R. Schneider , T. Roy Choudhury , A. Ferrara

A non-cosmological origin for the CMB quadrupole moment is suggested in this paper. Geometric distortions to an otherwise isotropic CMB could be imprinted on the CMB radiation as it propagates through the asymmetric termination shock formed…

Solar and Stellar Astrophysics · Physics 2009-05-20 H. N. Sharpe

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