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We investigate a possibility of constraining statistical anisotropies of the primordial tensor perturbations by using future observations for the Cosmic Microwave Background (CMB) B-mode polarization. By parameterizing a…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-24 Takashi Hiramatsu , Shuichiro Yokoyama , Tomohiro Fujita , Ippei Obata

Various so-called anomalies have been found in both the WMAP and Planck cosmic microwave background (CMB) temperature data that exert a mild tension against the highly successful best-fit 6 parameter cosmological model, potentially…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-25 A. J. Banday , C. Gimeno-Amo , P. Diego-Palazuelos , E. de la Hoz , A. Gruppuso , N. Raffuzzi , E. Martínez-González , P. Vielva , R. B. Barreiro , M. Bortolami , C. Chiocchetta , G. Galloni , D. Scott , R. M. Sullivan , D. Adak , E. Allys , A. Anand , J. Aumont , C. Baccigalupi , M. Ballardini , N. Bartolo , S. Basak , M. Bersanelli , A. Besnard , D. Blinov , F. Bouchet , T. Brinckmann , F. Cacciotti , E. Calabrese , P. Campeti , A. Carones , F. J. Casas , K. Cheung , M. Citran , L. Clermont , F. Columbro , A. Coppolecchia , P. de Bernardis , M. De Lucia , S. Della Torre , E. Di Giorgi , H. K. Eriksen , F. Finelli , C. Franceschet , U. Fuskeland , M. Galloway , M. Gervasi , R. T. Génova-Santos , T. Ghigna , S. Giardiello , M. Hazumi , L. T. Hergt , E. Hivon , K. Ichiki , H. Ishino , B. Jost , K. Kohri , L. Lamagna , M. Lattanzi , C. Leloup , F. Levrier , A. I. Lonappan , M. López-Caniego , G. Luzzi , J. Macias-Perez , V. Maranchery , S. Masi , S. Matarrese , T. Matsumura , S. Micheli , M. Migliaccio , M. Monelli , L. Montier , G. Morgante , M. Najafi , T. Namikawa , A. Novelli , I. Obata , A. Occhiuzzi , A. Paiella , D. Paoletti , G. Pascual-Cisneros , F. Piacentini , G. Piccirilli , G. Polenta , L. Porcelli , M. Remazeilles , A. Rizzieri , J. A. Rubiño-Martín , M. Ruiz-Granda , Y. Sakurai , J. Sanghavi , M. Shiraishi , G. Signorelli , Y. Takase , L. Terenzi , M. Tomasi , M. Tristram , L. Vacher , B. van Tent , I. K. Wehus , G. Weymann-Despres , E. J. Wollack , Y. Zhou

We investigate large-angle scale temperature anisotropy in the Cosmic Microwave Background (CMB) with the Wilkinson Microwave Anisotropy Probe (WMAP) data and model the large-angle anomalies as the effect of the CMB quadrupole anisotropies…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Li-Ping He , Quan Guo

Measurements of the cosmic microwave background (CMB) temperature anisotropies have revealed a dipolar asymmetry in power at the largest scales, in apparent contradiction with the statistical isotropy of standard cosmological models. The…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-07 D. Contreras , J. Hutchinson , A. Moss , D. Scott , J. P. Zibin

The current available CMB data show an anomalously low value of the CMB temperature fluctuations at large angular scales (l < 40). This lack of power is not explained by the minimal LCDM model, and one of the possible mechanisms explored in…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-07 Simony Santos da Costa , Micol Benetti , Jailson Alcaniz

Both WMAP and Planck data show a significant odd-multipole preference in the large scales of the cosmic microwave background (CMB) temperature anisotropies. If this pattern originates from cosmological effects, then it can be considered a…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-18 Cheng Cheng , Wen Zhao , Qing-Guo Huang , Larissa Santos

Observations of the Cosmic Microwave Background (CMB) have cemented the notion that the large-scale Universe is both statistically homogeneous and isotropic. But is it invariant also under reflections? To probe this we require…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-25 Oliver H. E. Philcox

Anomalies of the cosmic microwave background (CMB) maps have been widely acquainted nowadays from the Wilkinson Microwave Anisotropy Probe (WMAP) satellite to the Planck satellite. One of the anomalies is a multipole alignment from $l=2$ to…

High Energy Astrophysical Phenomena · Physics 2014-06-30 Lixiong Gan , Yuan-Chuan Zou , Zi-Gao Dai

The quadrupole power of cosmic microwave background (CMB) temperature anisotropies seen in the WMAP data is puzzlingly low. In this paper we demonstrate that Minimum Variance Optimization (MVO), a technique used by many authors (including…

Astrophysics · Physics 2009-03-18 Lung-Yih Chiang , Pavel D. Naselsky , Peter Coles

We repeat and extend the analysis of Eriksen et al 2004 and Hansen et al 2004 testing the isotropy of the Cosmic Microwave Background (CMB) fluctuations. We find that the hemispherical power asymmetry previously reported for the largest…

Astrophysics · Physics 2014-11-18 F. K. Hansen , A. J. Banday , K. M. Gorski , H. K. Eriksen , P. B. Lilje

Several unexpected features have been observed in the microwave sky at large angular scales, both by WMAP an by Planck. Among those features is a lack of both variance and correlation on the largest angular scales, alignment of the lowest…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-07 Dominik J. Schwarz , Craig J. Copi , Dragan Huterer , Glenn D. Starkman

We present new limits on the amplitude of potential primordial magnetic fields (PMFs) using temperature and polarization measurements of the cosmic microwave background (CMB) from Planck, BICEP2/Keck Array, POLARBEAR, and SPTpol. We reduce…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Dylan R. Sutton , Chang Feng , Christian L. Reichardt

We use quadratic maximum-likelihood (QML) estimators to constrain models with Gaussian but statistically anisotropic Cosmic Microwave Background (CMB) fluctuations, using CMB maps with realistic sky-coverage and instrumental noise. This…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-06 Duncan Hanson , Antony Lewis

We test anisotropic dark energy models with the 7-year WMAP temperature observations data. In the presence of imperfect sources, due to large-scale gradients or anisotropies in the dark energy field, the CMB sky will be distorted…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-08 Magnus J. Axelsson , Frode K. Hansen , Tomi Koivisto , David F. Mota

Measurements of the cosmic microwave background (CMB) allow high precision observation of the Last Scattering Surface at redshift $z\sim$1100. After the success of the NASA satellite COBE, that in 1992 provided the first detection of the…

We present a simple way of coding and compressing the data on board the Planck instruments (HFI and LFI) to address the problem of the on board data reduction. This is a critical issue in the Planck mission. The total information that can…

Astrophysics · Physics 2009-10-31 E. Gaztanaga , A. Romeo , J. Barriga , E. Elizalde

We examine the internal consistency of the Planck 2015 cosmic microwave background (CMB) temperature anisotropy power spectrum. We show that tension exists between cosmological constant cold dark matter (LCDM) model parameters inferred from…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-24 G. E. Addison , Y. Huang , D. J. Watts , C. L. Bennett , M. Halpern , G. Hinshaw , J. L. Weiland

Cosmic Microwave Background (CMB) experiments, such as WMAP and Planck, measure intensity anisotropies and build maps using a \emph{linearized} formula for relating them to the temperature blackbody fluctuations. However such a procedure…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-24 Alessio Notari , Miguel Quartin

We constrain several models of the early Universe that predict a statistical anisotropy of the cosmic microwave background (CMB) sky. We make use of WMAP9 maps deconvolved with beam asymmetries. As compared to previous releases of WMAP…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-03 Sabir Ramazanov , Grigory Rubtsov

We consider an inhomogeneous model and independently an anisotropic model of primordial power spectrum in order to describe the observed hemispherical anisotropy in Cosmic Microwave Background Radiation. This anisotropy can be parametrized…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-31 Rahul Kothari , Shamik Ghosh , Pranati K. Rath , Gopal Kashyap , Pankaj Jain
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