English
Related papers

Related papers: A search for concentric circles in the 7-year WMAP…

200 papers

WMAP observations have accurately determined the position of the first two peaks and dips in the CMB temperature power spectrum. These encode information on the ratio of the distance to the last scattering surface to the sound horizon at…

Astrophysics · Physics 2008-11-26 Pier Stefano Corasaniti , Alessandro Melchiorri

The Wilkinson Microwave Anisotropy Probe (WMAP) has mapped the full sky in Stokes I, Q, and U parameters at frequencies 23, 33, 41, 61, and 94 GHz. We detect correlations between the temperature and polarization maps significant at more…

A number of theoretically well-motivated additions to the standard cosmological model predict weak signatures in the form of spatially localized sources embedded in the cosmic microwave background (CMB) fluctuations. We present a…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-18 Stephen M. Feeney , Matthew C. Johnson , Jason D. McEwen , Daniel J. Mortlock , Hiranya V. Peiris

Gravitational lensing by large scale structure introduces non-Gaussianity into the Cosmic Microwave Background and imprints a new observable, which can be used as a cosmological probe. We apply a four-point estimator to the Wilkinson…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-06 Chang Feng , Brian Keating , Hans P. Paar , Oliver Zahn

We have conducted a systematic near-infrared circular polarization (CP) survey in star-forming regions, covering high-mass, intermediate-mass, and low-mass young stellar objects. All the observations were made using the SIRPOL imaging…

We develop a new Bayesian method for estimating white noise levels in CMB sky maps, and apply this algorithm to the 5-year WMAP data. We assume that the amplitude of the noise RMS is scaled by a constant value, alpha, relative to a…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-24 N. E. Groeneboom , H. K. Eriksen , K. Gorski , G. Huey , J. Jewell , B. Wandelt

We report and analyse the presence of foregrounds in the cosmic microwave background (CMB) radiation associated to extended galactic halos. Using the cross correlation of Planck and WMAP maps and the 2MRS galaxy catalogue, we find that the…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-19 Heliana E. Luparello , Ezequiel F. Boero , Marcelo Lares , Ariel G. Sánchez , Diego García Lambas

Using a Gibbs sampling algorithm for joint CMB estimation and component separation, we compute the large-scale CMB and foreground posteriors of the 3-yr WMAP temperature data. Our parametric data model includes the cosmological CMB signal…

Astrophysics · Physics 2010-11-11 H. K. Eriksen , C. Dickinson , J. B. Jewell , A. J. Banday , K. M. Gorski , C. R. Lawrence

Recently, full sky maps from Planck have been made publicly available. In this paper, we do consistency tests for the three Planck CMB sky maps. We assume that the difference between two maps represents the contributions from systematics,…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-27 Anne Mette Frejsel , Martin Hansen , Hao Liu

Temperature maps are presented of the 9 largest clusters in the mock catalogues of Muanwong et al. for both the Preheating and Radiative models. The maps show that clusters are not smooth, featureless systems, but contain a variety of…

Astrophysics · Physics 2009-11-07 Lesley I. Onuora , Scott T. Kay , Peter A. Thomas

Local scaling properties of the co-added foreground-cleaned three-year Wilkinson Microwave Anisotropy Probe (WMAP) data are estimated using weighted scaling indices. The scaling index method (SIM) is - for the first time - adapted and…

Astrophysics · Physics 2009-05-21 C. Raeth , P. Schuecker , A. J. Banday

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 cross-correlate the cosmic microwave background temperature anisotropy maps from the WMAP, MAXIMA-I, and MAXIMA-II experiments. We use the cross-spectrum, which is the spherical harmonic transform of the angular two-point correlation…

The non-Gaussian cold spot detected in wavelet space in the WMAP 1-year data, is detected again in the coadded WMAP 3-year data at the same position (b = -57, l = 209) and size in the sky (around 10 degrees). The present analysis is based…

Astrophysics · Physics 2008-11-26 M. Cruz , L. Cayon , E. Martinez-Gonzalez , P. Vielva , J. Jin

We compute the two-, three- and four-point correlation functions from the Wilkinson Microwave Anisotropy Probe (WMAP) first-year data, and compare these to a Monte Carlo ensemble of 5000 realizations, based on the best-fit WMAP…

Astrophysics · Physics 2009-11-10 H. K. Eriksen , A. J. Banday , K. M. Gorski , P. B. Lilje

We present a search for non-Gaussianity in the WMAP first-year data using the two-point correlation function of maxima and minima in the temperature map. We find evidence for non-Gaussianity on large scales, whose origin appears to be…

Astrophysics · Physics 2009-11-13 R. Tojeiro , P. G. Castro , A. F. Heavens , S. Gupta

The spectral variation of the cosmic microwave background (CMB) as observed by WMAP was tested using foreground reduced WMAP5 data, by producing subtraction maps at the 1$^\circ$ angular resolution between the two cosmological bands of V…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Bi-Zhu Jiang , Richard Lieu , Shuang-Nan Zhang , Bart Wakker

The latest cosmological data seem to indicate a significant deviation from scale invariance of the primordial power spectrum when parameterized either by a power law or by a spectral index with non-zero "running". This deviation, by itself,…

Astrophysics · Physics 2011-05-12 Licia Verde , Hiranya V. Peiris

We performed a comprehensive statistical analysis using complex phases of the a_lm coefficients computed from the most recent data of the Wilkinson Microwave Anisotropy Probe (WMAP). Our aim was to confirm or constrain the presence of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 András Kovács , István Szapudi , Zsolt Frei

We cross-correlate the recent CMB WMAP 1 year data with the diffuse soft X-ray background map of ROSAT. We look for common signatures due to galaxy clusters (SZ effect in CMB, bremsstrahlung in X-rays) by cross-correlating the two maps in…

Astrophysics · Physics 2015-06-24 J. M. Diego , J. Silk , W. Sliwa