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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 Correlated Component Analysis (CCA) allows us to estimate how the different diffuse emissions mix in CMB experiments, exploiting also complementary information from other surveys. It is especially useful to deal with possible additional…

Astrophysics · Physics 2009-01-13 A. Bonaldi , S. Ricciardi , S. Leach , F. Stivoli , C. Baccigalupi , G. De Zotti

Recent results of the ESA Planck satellite have confirmed the existence of some anomalies in the statistical distribution of the cosmic microwave background (CMB) anisotropies. One of the most intriguing anomalies is the Cold Spot, firstly…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 R. Fernández-Cobos , P. Vielva , E. Martínez-González , M. Tucci , M. Cruz

We present a thorough and detailed investigation of baryon isocurvature models including realistic thermal histories, \ie, late or partial reionization of the universe and compact object formation after standard recombination. Constraints…

Astrophysics · Physics 2009-07-17 Wayne Hu , Naoshi Sugiyama

Analyses of recent cosmic microwave background (CMB) observations have provided increasing indications for the existence of large scale anisotropy in the universe. Given the far reaching consequences of such an anisotropy for our…

Astrophysics · Physics 2009-09-29 A. Bernui , B. Mota , M. J. Reboucas , R. Tavakol

The low quadrupole of the cosmic microwave background (CMB), measured by COBE and confirmed by WMAP, has generated much discussion recently. We point out that the well-known correlation between temperature and polarization anisotropies of…

Astrophysics · Physics 2009-06-15 Olivier Doré , Gilbert P. Holder , Abraham Loeb

We describe a sampling method to estimate the polarized CMB signal from observed maps of the sky. We use a Metropolis-within-Gibbs algorithm to estimate the polarized CMB map, containing Q and U Stokes parameters at each pixel, and its…

We constrain the spectrum of primordial curvature perturbations by using recent Cosmic Microwave Background (CMB) and Large Scale Structure (LSS) data. Specifically, we consider CMB data from the COBE, Boomerang and Maxima experiments, the…

Astrophysics · Physics 2009-11-06 S. Hannestad , S. H. Hansen , F. L. Villante , A. J. S. Hamilton

Current observational bounds on dark energy depend on assumptions about the curvature of the universe. We present a simple and efficient method for incorporating constraints from CMB anisotropy data, and use it to derive constraints on…

Astrophysics · Physics 2010-04-06 Yun Wang , Pia Mukherjee

We study CMB constraints on non-Gaussianity from isocurvature perturbations of general types. Specifically, we study CDM/neutrino isocurvature perturbations which are uncorrelated or totally correlated with adiabatic ones. Using the data…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Chiaki Hikage , Masahiro Kawasaki , Toyokazu Sekiguchi , Tomo Takahashi

(abridged) We study the impact of the large-angle CMB polarization datasets publicly released by the WMAP and Planck satellites on the estimation of cosmological parameters of the $\Lambda$CDM model. To complement large-angle polarization,…

The main goals of this study is to use the information from both WMAP intensity and polarization data to do a separation of the Galactic components, with a focus on the synchrotron and anomalous emissions. Our analysis is made at 23 GHz…

(Abridged) We present the angular power spectra derived from the 7-year maps and discuss the cosmological conclusions that can be inferred from WMAP data alone. The third acoustic peak in the TT spectrum is now well measured by WMAP. In the…

Observations of the polarization of the cosmic microwave backround (CMB) have the potential to place much tighter constraints on cosmological parameters than observations of the fluctuations in temperature alone. We discuss using CMB…

Astrophysics · Physics 2009-10-30 William H. Kinney

We derive an upper limit on the neutrino mass from the WMAP three-year data alone by employing a deterministic minimisation method based on a grid search in multi-parameter space. Assuming the flat LCDM model with power-law adiabatic…

Astrophysics · Physics 2008-11-26 Masataka Fukugita , Kazuhide Ichikawa , Masahiro Kawasaki , Ofer Lahav

STPpol, POLARBEAR and BICEP2 have recently measured the cosmic microwave background (CMB) B-mode polarization in various sky regions of several tens of square degrees and obtained BB power spectra in the multipole range 20-3000, detecting…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-14 Sperello di Serego Alighieri , Wei-Tou Ni , Wei-Ping Pan

We investigate whether non-adiabatic perturbations from inflation could produce an asymmetric distribution of temperature anisotropies on large angular scales in the cosmic microwave background (CMB). We use a generalised non-linear $\delta…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Hooshyar Assadullahi , Hassan Firouzjahi , Mohammad Hossein Namjoo , David Wands

We have investigated the constraints on the Cardassian model using the recent results from the Wilkinson Microwave Anisotropy Probe (WMAP) for the locations of the peaks of the Cosmic Microwave Background (CMB) anistropy spectrum. We find…

Astrophysics · Physics 2016-08-30 A. A. Sen , S. Sen

We present the constraints on isocurvature fluctuations for a flat universe implied by the Boomerang and Maxima-1 data on the anisotropy of the cosmic microwave background. Because the new data defines the shape of the angular power…

Astrophysics · Physics 2008-11-26 Kari Enqvist , Hannu Kurki-Suonio , Jussi Valiviita

We investigate the accuracy attainable by forthcoming space-based observations of the cosmic microwave background (CMB) temperature and polarization anisotropy in constraining the dark energy density parameter $\Oq$ and equation of state…

Astrophysics · Physics 2009-11-07 A. Balbi , C. Baccigalupi , F. Perrotta , S. Matarrese , N. Vittorio
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