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In this paper, we combine the the latest observational data, including the WMAP five-year data (WMAP5), the baryon acoustic oscillations (BAO) and type Ia supernovae (SN) "union" compilation, and use the Markov Chain Monte Carlo method to…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-11 Hong Li , Jun-Qing Xia

We analyse WMAP 7-year temperature data, jointly modeling the cosmic microwave background (CMB) and Galactic foreground emission. We use the Commander code based on Gibbs sampling. Thus, from the WMAP7 data, we derive simultaneously the CMB…

We perform a wavelet analysis of the temperature and polarization maps of the Cosmic Microwave Background (CMB) delivered by the WMAP experiment in search for a parity violating signal. Such a signal could be seeded by new physics beyond…

Astrophysics · Physics 2008-11-26 Paolo Cabella , Paolo Natoli , Joseph Silk

The polarization of the Cosmic Microwave Background (CMB)is a powerful observational tool at hand for modern cosmology. It allows to break the degeneracy of fundamental cosmological parameters one cannot obtain using only anisotropy data…

Astrophysics · Physics 2007-05-23 M. V. Sazhin , G. Sironi , O. S. Khovanskaya

(Abridged) The WMAP 5-year data strongly limit deviations from the minimal LCDM model. We constrain the physics of inflation via Gaussianity, adiabaticity, the power spectrum shape, gravitational waves, and spatial curvature. We also…

Inter alia, the high precision WMAP data on Cosmic Microwave Background Radiation marginally indicate that the universe has positively curved (and hence spherical) spatial sections. In this paper, we take this data seriously and consider…

Astrophysics · Physics 2009-11-07 Jean-Philippe Uzan , Ulrich Kirchner , George F. R. Ellis

We present the first Bayesian constraints on the single field inflationary reheating era obtained from Cosmic Microwave Background (CMB) data. After demonstrating that this epoch can be fully characterized by the so-called reheating…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Jerome Martin , Christophe Ringeval

The improved data on the cosmic microwave background (CMB) anisotropy allow a better determination of the adiabaticity of the primordial perturbation. Interestingly, we find that recent CMB data seem to favor a contribution of a primordial…

Astrophysics · Physics 2008-11-26 Reijo Keskitalo , Hannu Kurki-Suonio , Vesa Muhonen , Jussi Valiviita

In the standard inflationary scenario, primordial perturbations are adiabatic. The amplitudes of most types of isocurvature perturbations are generally constrained by current data to be small. If, however, there is a baryon-density…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-24 Julian B. Muñoz , Daniel Grin , Liang Dai , Marc Kamionkowski , Ely D. Kovetz

We study the observational constraints of CMB temperature and polarization anisotropies on models of dark energy, with special focus on models with variation in properties of dark energy with time. We demonstrate that the key constraint…

Astrophysics · Physics 2014-10-13 H. K. Jassal , J. S. Bagla , T. Padmanabhan

We present new full-sky temperature and polarization maps in five frequency bands from 23 to 94 GHz, based on data from the first five years of the WMAP sky survey. The five-year maps incorporate several improvements in data processing made…

We use the WMAP 7 data to place constraints on oscillations supplementing an almost scale-invariant primordial power spectrum. Such oscillations are predicted by a variety of models, some of which amount to assuming there is some…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 P. Daniel Meerburg , Ralph Wijers , Jan Pieter van der Schaar

Parity-odd non-Gaussianities create a variety of temperature bispectra in the cosmic microwave background (CMB), defined in the domain: $\ell_1 + \ell_2 + \ell_3 = {\rm odd}$. These models are yet unconstrained in the literature, that so…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-09 Maresuke Shiraishi , Michele Liguori , James R. Fergusson

We assay how inflationary models whose properties are dominated by the dynamics of a single scalar field are constrained by cosmic microwave background (CMB) data from the Wilkinson Microwave Anisotropy Probe (WMAP). We classify…

High Energy Physics - Phenomenology · Physics 2009-09-15 V. Barger , Hye-Sung Lee , Danny Marfatia

Primordial fluctuations in the relative number densities of particles, or isocurvature perturbations, are generally well constrained by cosmic microwave background (CMB) data. A less probed mode is the compensated isocurvature perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-30 Chen He , Daniel Grin , Wayne Hu

In this paper we study the isocurvature mode contribution to the cosmic microwave background anisotropies and the large scale structure power spectrum, for a two-field model of inflation proposed by Linde and Mukhanov. We provide…

High Energy Physics - Phenomenology · Physics 2008-11-26 Elena Pierpaoli , Juan Garcia-Bellido , Stefano Borgani

A simple cosmological model with only six parameters (matter density, Omega_m h^2, baryon density, Omega_b h^2, Hubble Constant, H_0, amplitude of fluctuations, sigma_8, optical depth, tau, and a slope for the scalar perturbation spectrum,…

Two different predictions for the primordial curvature fluctuation bispectrum are compared through their effects on the Cosmic Microwave Background temperature fluctuations. The first has a local form described by a single parameter f_{NL}.…

Astrophysics · Physics 2009-06-23 Ian G Moss , Chris M Graham

We present new measurements of the cosmic microwave background (CMB) polarization from the final season of the Cosmic Anisotropy Polarization MAPper (CAPMAP). The data set was obtained in winter 2004-2005 with the 7 m antenna in Crawford…

Anomalies in the large-scale CMB temperature sky measured by WMAP have been suggested as possible evidence for a violation of statistical isotropy on large scales. In any physical model for broken isotropy, there are testable consequences…

Astrophysics · Physics 2008-12-18 Cora Dvorkin , Hiranya V. Peiris , Wayne Hu