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Related papers: Detection of non-Gaussianity in the WMAP 1-year da…

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In this paper we pursue the origin of the non-Gaussianity determined by a bispectrum analysis of the COBE-DMR 4-year sky maps. The robustness of the statistic is demonstrated by the rebinning of the data into 12 coordinate systems. By…

Astrophysics · Physics 2010-02-23 A. J. Banday , S. Zaroubi , K. M. Gorski

We use the full bispectrum of spherical needlets applied to the WMAP data of the cosmic microwave background as an estimator for the primordial non-Gaussianity parameter f_NL. We use needlet scales up to l_max=1000 and the KQ75 galactic cut…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-11 Oystein Rudjord , Frode K. Hansen , Xiaohong Lan , Michele Liguori , Domenico Marinucci , Sabino Matarrese

We have analyzed the efficiency in source detection and flux density estimation of blind and non-blind detection techniques exploiting the MHW2 filter applied to the Wilkinson Microwave Anisotropy Probe (WMAP) 5-year maps. A comparison with…

Astrophysics · Physics 2009-11-13 M. Massardi , M. López-Caniego , J. González-Nuevo , D. Herranz , G. De Zotti , J. L. Sanz

We use South Pole Telescope data from 2008 and 2009 to detect the non-Gaussian signature in the cosmic microwave background (CMB) produced by gravitational lensing and to measure the power spectrum of the projected gravitational potential.…

We present an alternative estimate of the unresolved point source contribution to the WMAP temperature power spectrum based on current knowledge of sources from radio surveys in the 1.4-90 GHz range. We implement a stochastic extrapolation…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Loris P. L. Colombo , Elena Pierpaoli

We revisit the anisotropic universe model previously developed by Ackerman, Carroll and Wise (ACW), and generalize both the theoretical and computational framework to include polarization and various forms of systematic effects. We apply…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Nicolaas E. Groeneboom , Lotty Ackerman , Ingunn Kathrine Wehus , Hans Kristian Eriksen

The three Minkowski functionals and the recently defined length of the skeleton are estimated for the co-added first-year Wilkinson Microwave Anisotropy Probe (WMAP) data and compared with 5000 Monte Carlo simulations, based on Gaussian…

Astrophysics · Physics 2008-11-26 H. K. Eriksen , D. I. Novikov , P. B. Lilje , A. J. Banday , K. M. Gorski

We present a new method to estimate three-point correlations in Cosmic Microwave Background maps. Our Fast Fourier Transform based implementation estimates three-point functions using all possible configurations (triangles) at a controlled…

Astrophysics · Physics 2009-11-13 Gang Chen , Istvan Szapudi

Non-commutative geometry at inflation can give arise to parity violating modulations of the primordial power spectrum. We develop the statistical tools needed for investigating whether these modulations are evident in the Cosmic Microwave…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-25 N. E. Groeneboom , M. Axelsson , D. F. Mota , T. Koivisto

(Abridged) Estimating the uncertainty on the matter power spectrum internally (i.e. directly from the data) is made challenging by the simple fact that galaxy surveys offer at most a few independent samples. In addition, surveys have…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Joachim Harnois-Deraps , Ue-Li Pen

We search the BOOMERanG maps of the anisotropy of the Cosmic Microwave Background (CMB) for deviations from gaussianity. In this paper we focus on analysis techniques in pixel-space, and compute skewness, kurtosis and Minkowski functionals…

The first-year WMAP data, in combination with any one of a number of other cosmic probes, show that we live in a flat \Lambda-dominated CDM universe with \Omega_m ~ 0.27 and \Omega_\Lambda ~ 0.73. In this model the late-time action of the…

A remarkable similarity between the large-scale non-Gaussian pattern of cosmic microwave background (CMB) temperatures obtained by Wilkinson Microwave Anisotropy Probe (WMAP) mission and the distribution feature of observation numbers is…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-01 Ti-Pei Li , Hao Liu , Li-Ming Song , Shao-Lin Xiong , Jian-Yin Nie

Since the first LIGO/Virgo detection, Gravitational Waves (GWs) have been very promising as a new complementary probe to understand our Universe. One of the next challenges of GW search is the detection and characterization of the…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-14 Gabriele Perna , Angelo Ricciardone , Daniele Bertacca , Sabino Matarrese

In this work we present constraints on different shapes of primordial non-Gaussianity using the Wilkinson Microwave Anisotropy Probe (WMAP) 7-year data and the spherical Mexican hat wavelet fnl estimator including the linear term…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 A. Curto , E. Martinez-Gonzalez , R. B. Barreiro

A search for matched circle pairs of similar temperature fluctuations in the final WMAP 9yr data is carried out. Such a signature is expected if the space of the Universe is multiply connected. We investigate the relation between the pixel…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-22 Ralf Aurich , Sven Lustig

The identification and extraction of non-Gaussian signals is one of the main cosmological challenges facing future experimental measurements of the cosmic microwave background temperature pattern. We present a generalized statistical…

Astrophysics · Physics 2009-11-07 Lung-Yih Chiang , Pavel Naselsky , Peter Coles

We introduce and study the distribution of an estimator for the normalized bispectrum of the Cosmic Microwave Background (CMB) anisotropy. We use it to construct a goodness of fit statistic to test the coadded 53 and 90 GHz COBE-DMR 4 year…

Astrophysics · Physics 2009-10-30 Pedro G. Ferreira , Joao Magueijo , Krzysztof M. Górski

We review our recent claim that there is evidence of non-Gaussianity in the 4 Year COBE DMR data. We present some new results concerning the effect of the galactic cut upon the non-Gaussian signal. These findings imply a localization of the…

Astrophysics · Physics 2009-10-31 Joao Magueijo , Pedro G. Ferreira , Krzysztof M. Gorski

Recent simulations show the Epoch of Reionization (EoR) 21-cm signal to be inherently non-Gaussian whereby the error covariance matrix $\mathbf{C}_{ij}$ of the 21-cm power spectrum (PS) contains a trispectrum contribution that would be…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-01 Abinash Kumar Shaw , Somnath Bharadwaj , Rajesh Mondal