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Related papers: Dipole Anisotropy in the COBE DMR First-Year Sky M…

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The hierarchy of motions that we are participating is well known, from the Earth's motion around the Sun and Sun's motion in the Milky Way, up to the Local Group's motion within the Virgo Supercluster of galaxies. The dipole anisotropy of…

Astrophysics of Galaxies · Physics 2021-11-03 V. G. Gurzadyan , A. L. Kashin , A. A. ~Kocharyan , A. Stepanian

The recent study of BOOMERanG 150 GHz Cosmic Microwave Background (CMB) radiation maps have detected ellipticity of the temperature anisotropy spots independent on the temperature threshold. The effect has been found for spots up to several…

An observer in relative motion to the Cosmic Microwave Background (CMB) rest frame is sensitive to both aberration and Doppler effects. Both effects introduce similar but non-identical off-diagonal couplings in the spherical harmonic…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-06 Pedro da Silveira Ferreira , Miguel Quartin

Our local motion with respect to the cosmic frame of rest is believed to be dominantly responsible for the observed dipole anisotropy in the Cosmic Microwave Background Radiation (CMBR). We study the effect of this motion on the sky…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-21 Gopal Kashyap , Naveen K. Singh , Khun Sang Phukon , Sarah Caudill , Pankaj Jain

Density perturbations at the decoupling epoch produce angular fluctuations in the temperature of the Cosmic Microwave Background (CMB) radiation that may appear as hot and cold spots. Observational data of the CMB includes instrumental…

Astrophysics · Physics 2009-10-28 Laura Cayon , George Smoot

We determine the dipole in the WISE galaxy catalogue. After reducing star contamination to <0.1% by rejecting sources with high apparent motion and those close to the Galactic plane, we eliminate low redshift sources to suppress the…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-30 M. Rameez , R. Mohayaee , S. Sarkar , J. Colin

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 analyze the Cosmic Microwave Background (CMB) anisotropy data from the independent COBE FIRAS and DMR observations. We extract the frequency spectrum of the FIRAS signal that has the spatial distribution seen by DMR and show that it is…

Astrophysics · Physics 2009-10-30 D. J. Fixsen , G. Hinshaw , C. L. Bennett , J. C. Mather

We report the detection of polarized anisotropy in the Cosmic Microwave Background radiation with the Degree Angular Scale Interferometer (DASI), located at the Amundsen-Scott South Pole research station. Observations in all four Stokes…

Astrophysics · Physics 2011-05-05 J. Kovac , E. M. Leitch , C. Pryke , J. E. Carlstrom , N. W. Halverson , W. L. Holzapfel

We estimate the depolarizing effect of a primordial magnetic field upon the cosmic microwave background radiation due to differential Faraday rotation across the last scattering surface. The degree of linear polarization of the CMB is…

Astrophysics · Physics 2014-10-13 Diego Harari , Justin Hayward , Matias Zaldarriaga

The first observations of the cosmic microwave background (CMB) from NASA's \emph{Wilkinson Microwave Anisotropy Probe} (WMAP) led to finding `alignment' anomalies not expected from fluctuations in the isotropic cosmological model. We study…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-03 Sanjeet Kumar Patel , Pavan Kumar Aluri , John P. Ralston

Several statistical anomalies in the CMB temperature anisotropies seem to defy the assumption of a homogeneous and isotropic universe. In particular, a dipole modulation has been detected both in WMAP and Planck data. We adapt the…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-29 R. Fernández-Cobos , P. Vielva , D. Pietrobon , A. Balbi , E. Martínez-González , R. B. Barreiro

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

Astrophysics · Physics 2007-05-23 Tarun Souradeep , Amir Hajian

The sky-RMS is the simplest model-independent characterization of a cosmological anisotropy signal. The RMS temperature fluctuations determined from the $COBE$-DMR four-year sky maps are frequency independent, consistent with the hypothesis…

The motion of our solar system relative to the CMB rest frame leads to subtle distortions in the observed CMB sky map due to the aberration effect. Usually the corresponding peculiar velocity is determined from the CMB dipole but neglecting…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-30 Ralf Aurich , David Reinhardt

To reliably detect the cosmic microwave background (CMB) anisotropy is of great importance in understanding the birth and evolution of the Universe. One of the difficulties in CMB experiments is the domination of measured CMB anisotropy…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-28 Hao Liu , Ti-Pei Li

The dipole anisotropy seen in the {cosmic microwave background radiation} is interpreted as due to our peculiar motion. The Cosmological Principle implies that this cosmic dipole signal should also be present, with the same direction, in…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-24 Carlos A. P. Bengaly , Thilo M. Siewert , Dominik J. Schwarz , Roy Maartens

We question the global universe isotropy by probing the alignment of local structures in the cosmic microwave background (CMB) radiation. The original method proposed relies on a steerable wavelet decomposition of the CMB signal on the…

Astrophysics · Physics 2007-05-23 Y. Wiaux , P. Vielva , E. Martinez-Gonzalez , P. Vandergheynst

We investigate the imprint of nonlinear matter condensations on the Cosmic Microwave Background (CMB) in an $\Omega=1$, Cold Dark Matter (CDM) model universe. Temperature anisotropies are obtained by numerically evolving matter…

Astrophysics · Physics 2016-08-30 Robin Tuluie , Pablo Laguna

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