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Related papers: Features in the Primordial Spectrum from WMAP: A W…

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CMB photons travel from the last scattering surface, when the primary CMB has been generated, along the surface of the light cone to us. During their travel, they are affected by many secondary effects such as the integrated Sachs-Wolfe…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-11 Mario Ballardini

Statistical isotropy of primordial perturbations is a common assumption in cosmology, but it is an assumption that should be tested. To this end, we develop cosmic microwave background statistics for a primordial power spectrum that depends…

Astrophysics · Physics 2008-12-18 Anthony R. Pullen , Marc Kamionkowski

Most parameter constraints obtained from cosmic microwave background (CMB) anisotropy data are based on power estimates and rely on approximate likelihood functions; computational difficulties generally preclude an exact analysis based on…

Astrophysics · Physics 2009-11-06 M. Douspis , J. G. Bartlett , A. Blanchard , M. Le Dour

In recent years the goal of estimating different cosmological parameters precisely has set new challenges in the effort to accurately measure the angular power spectrum of CMB. This has required removal of foreground contamination as well…

Astrophysics · Physics 2008-11-26 Rajib Saha , Simon Prunet , Pankaj Jain , Tarun Souradeep

We use the results from the Wilkinson Microwave Anisotropy Probe (WMAP) for the locations of peaks and troughs of the Cosmic Microwave Background (CMB) power spectrum, together with constraints from large-scale structure, to study a…

Astrophysics · Physics 2016-11-09 T. Barreiro , M. C. Bento , N. M . C. Santos , A. A. Sen

We develop an accurate and efficient Bayesian method to reconstruct the primordial power spectrum in a model-independent way, and apply it to the latest cosmic microwave background measurement from Planck mission, and the large scale…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-28 Xin Wang , Gong-Bo Zhao

The six parameters of the standard $\Lambda$CDM model have best-fit values derived from the Planck temperature power spectrum that are shifted somewhat from the best-fit values derived from WMAP data. These shifts are driven by features in…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-22 Planck Collaboration , N. Aghanim , Y. Akrami , M. Ashdown , J. Aumont , M. Ballardini , A. J. Banday , R. B. Barreiro , N. Bartolo , S. Basak , K. Benabed , M. Bersanelli , P. Bielewicz , A. Bonaldi , L. Bonavera , J. R. Bond , J. Borrill , F. R. Bouchet , C. Burigana , E. Calabrese , J. -F. Cardoso , A. Challinor , H. C. Chiang , L. P. L. Colombo , C. Combet , B. P. Crill , A. Curto , F. Cuttaia , P. de Bernardis , A. de Rosa , G. de Zotti , J. Delabrouille , E. Di Valentino , C. Dickinson , J. M. Diego , O. Doré , A. Ducout , X. Dupac , S. Dusini , G. Efstathiou , F. Elsner , T. A. Enßlin , H. K. Eriksen , Y. Fantaye , F. Finelli , F. Forastieri , M. Frailis , E. Franceschi , A. Frolov , S. Galeotta , S. Galli , K. Ganga , R. T. Génova-Santos , M. Gerbino , J. González-Nuevo , K. M. Górski , A. Gruppuso , J. E. Gudmundsson , D. Herranz , E. Hivon , Z. Huang , A. H. Jaffe , W. C. Jones , E. Keihänen , R. Keskitalo , K. Kiiveri , J. Kim , T. S. Kisner , L. Knox , N. Krachmalnicoff , M. Kunz , H. Kurki-Suonio , G. Lagache , J. -M. Lamarre , A. Lasenby , M. Lattanzi , C. R. Lawrence , M. Le Jeune , F. Levrier , A. Lewis , P. B. Lilje , M. Lilley , V. Lindholm , M. López-Caniego , P. M. Lubin , Y. -Z. Ma , J. F. Macías-Pérez , G. Maggio , D. Maino , N. Mandolesi , A. Mangilli , M. Maris , P. G. Martin , E. Martínez-González , S. Matarrese , N. Mauri , J. D. McEwen , P. R. Meinhold , A. Mennella , M. Migliaccio , M. Millea , M. -A. Miville-Deschênes , D. Molinari , A. Moneti , L. Montier , G. Morgante , A. Moss , A. Narimani , P. Natoli , C. A. Oxborrow , L. Pagano , D. Paoletti , G. Patanchon , L. Patrizii , V. Pettorino , F. Piacentini , L. Polastri , G. Polenta , J. -L. Puget , J. P. Rachen , B. Racine , M. Reinecke , M. Remazeilles , A. Renzi , M. Rossetti , G. Roudier , J. A. Rubiño-Martín , B. Ruiz-Granados , L. Salvati , M. Sandri , M. Savelainen , D. Scott , C. Sirignano , G. Sirri , L. Stanco , A. -S. Suur-Uski , J. A. Tauber , D. Tavagnacco , M. Tenti , L. Toffolatti , M. Tomasi , M. Tristram , T. Trombetti , J. Valiviita , F. Van Tent , P. Vielva , F. Villa , N. Vittorio , B. D. Wandelt , I. K. Wehus , M. White , A. Zacchei , A. Zonca

(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…

Angular anisotropy techniques for cosmic diffuse radiation maps are powerful probes, even for quite small data sets. A popular observable is the angular power spectrum; we present a detailed study applicable to any unbinned source skymap…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Sheldon S. Campbell

Using a directional spherical wavelet analysis we detect the integrated Sachs-Wolfe (ISW) effect, indicated by a positive correlation between the first-year Wilkinson Microwave Anisotropy Probe (WMAP) and NRAO VLA Sky Survey (NVSS) data.…

Astrophysics · Physics 2009-09-29 J. D. McEwen , P. Vielva , M. P. Hobson , E. Martinez-Gonzalez , A. N. Lasenby

Constraints on the main cosmological parameters using CMB or large scale structure data are usually based on power-law assumption of the primordial power spectrum (PPS). However, in the absence of a preferred model for the early universe,…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-14 Dhiraj Kumar Hazra , Arman Shafieloo , Tarun Souradeep

We carry out the determination of the amplitude of relic gravitational waves power spectrum. Indirect best-fit technique was applied to compare observational data and theory predictions. As observations we have used data on large-scale…

Astrophysics · Physics 2007-05-23 B. Novosyadlyj , S. Apunevych

We present new constraints on possible features in the primordial inflationary density perturbations power spectrum in light of the recent Cosmic Microwave Background Anisotropies measurements from the Planck satellite. We found that the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Micol Benetti

In this work we explore the power of future large-scale surveys to constrain possible deviations from the standard single-field slow-roll inflationary scenario. Specifically, we parametrize possible fluctuations around the almost…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-14 Muhammad Sadegh Esmaeilian , Marzieh Farhang , Shirin Khodabakhshi

We perform a cosmological analysis in which we allow the primordial power spectrum of scalar perturbations to assume a shape that is different with respect to the usual power-law, arising from the simplest models of cosmological inflation.…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-22 Stefano Gariazzo

We show that the first year results of the Wilkinson Microwave Anisotropy Probe (WMAP) constrain very efficiently the energy density in relativistic particles in the universe. We derive new bounds on additional relativistic degrees of…

Astrophysics · Physics 2016-08-30 Patrick Crotty , Julien Lesgourgues , Sergio Pastor

Cosmological models predict transfer functions by which primordial density perturbations develop into CMB anisotropy and Large-Scale Structure. We use the current set of observations to reconstruct the primordial power spectrum for standard…

Astrophysics · Physics 2007-05-23 Eric Gawiser

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

We constrain several models of the early Universe that predict a statistical anisotropy of the cosmic microwave background (CMB) sky. We make use of WMAP9 maps deconvolved with beam asymmetries. As compared to previous releases of WMAP…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-03 Sabir Ramazanov , Grigory Rubtsov

The angular power spectrum estimator developed by Peebles (1973) and Hauser & Peebles (1973) has been modified and applied to the 2 year maps produced by the COBE DMR. The power spectrum of the real sky has been compared to the power…

Astrophysics · Physics 2009-09-25 E. L. Wright , G. F. Smoot , C. L. Bennett , P. M. Lubin
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