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The existing analysis of WMAP data is based on approximations for the likelihood function, which is likely to be inaccurate on large scales. Here we present exact evaluations of the likelihood of the low multipoles by direct inversion of…

Astrophysics · Physics 2009-11-10 A. Slosar , U. Seljak , A. Makarov

We present a new estimate of foreground emission in the WMAP data, using a Markov chain Monte Carlo (MCMC) method. The new technique delivers maps of each foreground component for a variety of foreground models, error estimates of the…

[Abridged] We have produced a cleaned map of the Wilkinson Microwave Anisotropy Probe (WMAP) 3-year data using an improved foreground subtraction technique. We perform an internal linear combination (ILC) to subtract the Galactic foreground…

Astrophysics · Physics 2008-11-26 Chan-Gyung Park , Changbom Park , J. Richard Gott

In cosmic microwave background (CMB) experiments, foreground-cleaned temperature maps are still contaminated by the residual dipole due to uncertainties of the Doppler dipole direction and microwave radiometer sidelobe. To obtain reliable…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-16 Hao Liu , Ti-Pei Li

Recent analyses of the WMAP data have suggested that the low-order multipoles of the CMB anisotropy distribution show cosmologically interesting and unexpected morphologies and amplitudes. In this paper, we apply a power equalization (PE)…

Astrophysics · Physics 2009-11-10 P. Bielewicz , K. M. Gorski , A. J. Banday

[Abridged] We apply the multipole vector framework to full-sky maps derived from the first year WMAP data. We significantly extend our earlier work showing that the two lowest cosmologically interesting multipoles, l=2 and 3, are not…

Astrophysics · Physics 2009-11-11 C. J. Copi , D. Huterer , D. J. Schwarz , G. D. Starkman

We search for planar deviations of statistical isotropy in the Wilkinson Microwave Anisotropy Probe (WMAP) data by applying a recently introduced angular-planar statistics both to full-sky and to masked temperature maps, including in our…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 L. Raul Abramo , Armando Bernui , Thiago S. Pereira

Obscuration due to Galactic emission complicates the extraction of information from cosmological surveys, and requires some combination of the (typically imperfect) modeling and subtraction of foregrounds, or the removal of part of the sky.…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-14 Stephen M. Feeney , Hiranya V. Peiris , Andrew Pontzen

Large-scale anomalies have been reported in CMB data with both WMAP and Planck data. These could be due to foreground residuals and or systematic effects, though their confirmation with Planck data suggests they are not due to a problem in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 A. Rassat , J. -L. Starck , P. Paykari , F. Sureau , J. Bobin

We apply the recently defined multipole vector framework to the frequency-specific first-year WMAP sky maps, estimating the low-l multipole coefficients from the high-latitude sky by means of a power equalization filter. While most previous…

Astrophysics · Physics 2009-11-13 P. Bielewicz , H. K. Eriksen , A. J. Banday , K. M. Gorski , P. B. Lilje

We present a framework and an open-source python toolkit to analyse the 2-point statistics of 3D fluctuations in the context of HI intensity maps using the multipole expansion formalism. We include simulations of the cosmological HI signal…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-19 Steven Cunnington , Alkistis Pourtsidou , Paula S. Soares , Chris Blake , David Bacon

We revisit the alignments of the largest structures observed in the cosmic microwave background (CMB) using the seven and nine-year WMAP and first-year Planck data releases. The observed alignments -- the quadrupole with the octopole and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Craig J. Copi , Dragan Huterer , Dominik J. Schwarz , Glenn D. Starkman

Polarization is the next frontier of CMB analysis, but its signal is dominated over much of the sky by foregrounds which must be carefully removed. To determine the efficacy of this cleaning it is necessary to have sensitive tests for…

Astrophysics · Physics 2007-09-06 Duncan Hanson , Douglas Scott , Emory F. Bunn

We investigate the large scale anomalies in the angular distribution of the cosmic microwave background radiation as measured by WMAP using several tests. These tests, based on the multipole vector expansion, measure correlations between…

WMAP has provided CMB maps of the full sky. The raw data is subject to foreground contamination, in particular near to the Galactic plane. Foreground cleaned maps have been derived, e.g., the internal linear combination (ILC) map of Bennett…

Astrophysics · Physics 2008-11-26 H. Then

We analyze whether there is any residual foreground contamination in the cleaned WMAP 7 years data for the differential assemblies, Q, V and W. We calculate the correlation between the foreground map, from which long wavelength correlations…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Pravabati Chingangbam , Changbom Park

In this paper, we present a foreground analysis of the WMAP 5-year data using the FASTICA algorithm, improving on the treatment of the WMAP 3-year data in Bottino et al 2008. We revisit the nature of the free-free spectrum with the emphasis…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 M. Bottino , A. J. Banday , D. Maino

ABRIDGED: We introduce and analyze a method for testing statistical isotropy and Gaussianity and apply it to the WMAP CMB foreground reduced, temperature maps, and cross-channel difference maps. We divide the sky into regions of varying…

Astrophysics · Physics 2009-06-23 Bartosz Lew

We analyze the effect of foregrounds on the observed alignment of CMBR quadrupole and octopole. The alignment between these multipoles is studied by using a symmetry based approach which assigns a principal eigenvector (PEV) or an axis with…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-03 Pavan K. Aluri , Pramoda K. Samal , Pankaj Jain , John. P. Ralston

The extraction of a 'haze' from the WMAP microwave skymaps is based on subtraction of known foregrounds, viz. free-free (bremsstrahlung), thermal dust and synchrotron, each traced by other skymaps. While the 408 MHz all-sky survey is used…

High Energy Astrophysical Phenomena · Physics 2010-10-19 Philipp Mertsch , Subir Sarkar
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