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Related papers: Maximum-Likelihood Analysis of the COBE Angular Co…

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The power spectrum (PS) of mass density fluctuations, independent of `biasing', is estimated from the Mark III catalog of peculiar velocities using Bayesian statistics. A parametric model is assumed for the PS, and the free parameters are…

Astrophysics · Physics 2009-10-28 S. Zaroubi , I. Zehavi , A. Dekel , Y. Hoffman , T. Kolatt

The first two years of COBE DMR observations of the CMB anisotropy are analyzed and compared with our previously published first year results. The results are consistent, but the addition of the second year of data increases the precision…

The power spectrum (PS) of {\it mass} density fluctuations, independent of ``biasing", is estimated from the Mark3 Catalog of Peculiar Velocities of galaxies using Bayesian statistics. A parametric model is assumed for the PS, and the free…

Astrophysics · Physics 2016-08-30 S. Zaroubi , A. Dekel , Y. Hoffman , T. Kolatt

We employ a pixel-based likelihood technique to estimate the angular power spectrum of the COBE Differential Microwave Radiometer (DMR) 4-year sky maps. The spectrum is consistent with a scale-invariant power-law form with a normalization,…

Astrophysics · Physics 2009-10-28 G. Hinshaw , A. J. Banday , C. L. Bennett , K. M. Gorski , A. Kogut , G. F. Smoot , E. L. Wright

A phenomenological power spectrum of primordial density perturbations has been constructed by using both COBE data to probe the large wavelength region, and a double power law, locally deduced from galaxy catalogs, which describes the…

Astrophysics · Physics 2008-02-03 S. Torres , R. Fabbri , R. Ruffini

This is a brief progress report on a long-term collaborative project to measure the power spectrum (PS) of mass density fluctuations from the Mark III and the SFI catalogs of peculiar velocities. The PS is estimated by applying maximum…

Astrophysics · Physics 2007-05-23 Idit Zehavi

We have made a likelihood statistical analysis of the angular correlations in the {\it COBE}-DMR two-year sky maps by Monte Carlo simulation of the temperature fluctuations. We assume an open universe and consider as primordial power…

Astrophysics · Physics 2015-06-24 L. Cayon , E. Martinez-Gonzalez , J. L. Sanz , N. Sugiyama , S. Torres

We construct a simple analytical model to study the effects of cosmic strings on the microwave background radiation. Our model is based on counting random multiple impulses inflicted on photon trajectories by the string network between the…

High Energy Physics - Phenomenology · Physics 2009-10-22 Leandros Perivolaropoulos

The power spectrum of mass density fluctuations is estimated from the Mark III and the SFI catalogs of peculiar velocities by applying a maximum likelihood analysis, using parametric models for the power spectrum and for the errors.…

Astrophysics · Physics 2007-05-23 Idit Zehavi

We perform the stastistics of temperature maxima and minima in COBE-DMR 2-year maps. For power-law spectra the surface distribution of peaks implies an amplitude consistent with more conventional analyses of COBE data (for instance, we get…

Astrophysics · Physics 2011-05-10 R. Fabbri , S. Torres

The index $n$ of a power law power spectrum of primordial density fluctuations, $P(k) \propto k^n$, has been estimated using many different techniques. The most precise compare the COBE DMR large angular scale $\Delta T$ to the amplitude of…

Astrophysics · Physics 2007-05-23 Edward L. Wright

We use a Quadratic Maximum Likelihood (QML) method to estimate the angular power spectrum of the cross-correlation between cosmic microwave background and large scale structure maps as well as their individual auto-spectra. We describe our…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 F. Schiavon , F. Finelli , A. Gruppuso , A. Marcos-Caballero , P. Vielva , R. G. Crittenden , R. B. Barreiro , E. Martinez-Gonzalez

We estimate the mass density fluctuations power spectrum (PS) on large scales by applying a maximum likelihood technique to the peculiarvelocity data of the recently completed redshift-distance survey of early-type galaxies (ENEAR). The…

A new technique of Fourier analysis on a cut sky (Gorski, 1994) has been applied to the two year COBE DMR sky maps. The Bayesian power spectrum estimation results are consistent with the Harrison-Zel'dovich n=1 model. The maximum likelihood…

Astrophysics · Physics 2009-06-16 K. M. Gorski , G. Hinshaw , A. J. Banday , C. L. Bennett , E. L. Wright , A. Kogut , G. F. Smoot , P. Lubin

Cosmological theories for the origin and evolution of structure in the Universe are highly predictive of the form of the angular power spectrum of cosmic microwave background fluctuations. We present new results from a comprehensive study…

Astrophysics · Physics 2007-05-23 Stephen Hancock , Graca Rocha

A statistical analysis of texture on the {\it COBE}-DMR first year sky maps based on the genus and spot number is presented. A generalized $\chi^2$ statistic is defined in terms of ``observable'' quantities: the genus and spot density that…

Astrophysics · Physics 2015-06-24 S. Torres , L. Cayon , E. Martinez-Gonzalez , J. L. Sanz

More than a dozen papers analyzing the COBE data have now appeared. We review the different techniques and compare them to a ``brute force" likelihood analysis where we invert the full 4038 x 4038 Galaxy-cut pixel covariance matrix. This…

Astrophysics · Physics 2008-11-26 Max Tegmark , Emory Bunn

We use the POTENT reconstruction of the mass density field in the nearby universe to estimate the amplitude of the density fluctuation power spectrum for various cosmological models. We find sigma_8\Omega_m^{0.6}= 1.3^{+0.4}_{-0.3}, almost…

Astrophysics · Physics 2009-10-22 Uros Seljak , Edmund Bertschinger

The frequency-independent RMS temperature fluctuations determined from the COBE-DMR two year sky maps are used to infer the parameter Q_{rms-PS}, which characterizes the normalization of power law models of primordial cosmological…

Using COBE-DMR 4-year data, we find a general expression yielding the likelihood distribution in the 3-dimensional parameter space spanned by the spectral index $n$, the spectral amplitude $a_{10}$ and the false-vacuum density parameter…

Astrophysics · Physics 2009-11-06 Marco Tucci , Angela Contaldo , Silvio Bonometto
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