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We present results from a first test of the Gaussianity of degree-scale cosmic microwave background (CMB) anisotropy. We investigate Gaussianity of the CMB anisotropy by studying the topology of CMB anisotropy maps from the QMAP and…

Astrophysics · Physics 2009-10-07 Chan-Gyung Park , Changbom Park , Bharat Ratra , Max Tegmark

We present a measurement of the angular power spectrum of the cosmic microwave background (CMB) using data from the South Pole Telescope (SPT). The data consist of 790 square degrees of sky observed at 150 GHz during 2008 and 2009. Here we…

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

We investigate the anisotropy in cosmic microwave background Planck maps due to the coupling between its beam asymmetry and uneven scanning strategy. Introducing a pixel space estimator based on the temperature gradients, we find a highly…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-17 Ben Rathaus , Ely D. Kovetz

The anisotropies in the cosmic microwave background (CMB) provide our best laboratory for testing models of the formation and evolution of large-scale structure. The rich features in the cosmic microwave background anisotropy spectrum, in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Zhen Pan , Lloyd Knox , Martin White

Scattering of cosmic microwave background (CMB) radiation in galaxy clusters induces a polarization signal proportional to the CMB quadrupole anisotropy at the cluster's location and look-back time. A survey of such remote quadrupole…

Astrophysics · Physics 2007-05-23 Emory F. Bunn

Combined analyses of WMAP 3-year and ACBAR Cosmic Microwave Anisotropies angular power spectra have presented evidence for gravitational lensing >3 sigma level. This signal could provide a relevant test for cosmology. After evaluating and…

Galactic foreground emission is a limiting factor for precise cosmic microwave background (CMB) anisotropy measurements. We perform an angular power spectrum analysis (APS) of all-sky total intensity maps at 408 MHz and 1420 MHz, which are…

Astrophysics · Physics 2009-11-13 L. La Porta , C. Burigana , W. Reich , P. Reich

The Wilkinson Microwave Anisotropy Probe (WMAP) has mapped the full sky in five frequency bands between 23 and 94 GHz. The primary goal of the mission is to produce high-fidelity, all-sky, polarization-sensitive maps that can be used to…

Astrophysics · Physics 2007-05-23 Lyman Page

As the era of high precision cosmology approaches, the empirically determined power spectrum of the microwave background anisotropy $C_l$ will provide a crucial test for cosmological theories. We present an exact semi-analytic framework for…

Astrophysics · Physics 2015-06-24 Benjamin D. Wandelt , Eric Hivon , Krzysztof M. Gorski

We propose a new formalism to handle asymmetric beams in the data analysis of cosmic microwave background anisotropy experiments. For any beam shape, the formalism finds the optimal circularly symmetric equivalent and is thus easily…

Simulated observations of a $10\dg \times 10\dg$ field by the Microwave Anisotropy Probe (MAP) are analysed in order to separate cosmic microwave background (CMB) emission from foreground contaminants and instrumental noise and thereby…

Astrophysics · Physics 2009-10-31 A. W. Jones , M. P. Hobson , A. N. Lasenby

The large-angle (low-ell) correlations of the Cosmic Microwave Background (CMB) as reported by the Wilkinson Microwave Anisotropy Probe (WMAP) after their first year of observations exhibited statistically significant anomalies compared to…

Astrophysics · Physics 2008-11-26 Craig J. Copi , Dragan Huterer , Dominik J. Schwarz , Glenn D. Starkman

Statistical Isotropy of the Cosmic Microwave Background (CMB) radiation has been studied and debated extensively in recent years. Under this assumption, the hot spots and cold spots of the CMB are expected to be uniformly distributed over a…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-14 Md Ishaque Khan , Rajib Saha

The third flight of the Medium Scale Anisotropy Measurement (MSAM1), in June 1995, observed a new strip of sky, doubling the sky coverage of the original MSAM1 dataset. MSAM1 observes with a 0.5 deg beam size in four bands from 5-20 icm.…

Gaussianity and statistical isotropy of the Universe are modern cosmology's minimal set of hypotheses. In this work we introduce a new statistical test to detect observational deviations from this minimal set. By defining the temperature…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-30 Thiago S. Pereira , L. Raul Abramo

Measurements of CMB anisotropy are ideal experiments for discovering the non-trivial global topology of the universe. To evaluate the CMB anisotropy in multiply-connected compact cosmological models, one needs to compute eigenmodes of the…

Astrophysics · Physics 2007-05-23 Kaiki Taro Inoue

We review the recently found large-scale anomalies in the maps of temperature anisotropies in the cosmic microwave background. These include alignments of the largest modes of CMB anisotropy with each other and with geometry and direction…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-10 Craig J. Copi , Dragan Huterer , Dominik J. Schwarz , Glenn D. Starkman

During the past two decades, experiments in both the northern and southern hemispheres have observed a small but measurable energy-dependent sidereal anisotropy in the arrival direction distribution of Galactic cosmic rays with relative…

High Energy Astrophysical Phenomena · Physics 2017-08-11 The HAWC Collaboration , The IceCube Collaboration

We have investigated the cosmic microwave background (CMB) anisotropy in closed multiply connected universes (flat and hyperbolic) with low matter density. We show that the COBE constraints on these low matter density models with…

Astrophysics · Physics 2016-08-30 Kaiki Taro Inoue
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