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Astrophysical and cosmological signals such as the cosmic microwave background radiation, as observed, typically contain contributions of different components, and their statistical properties can be used to distinguish one from the other.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 V. G. Gurzadyan , T. Ghahramanyan , S. Sargsyan

The technique of degree of randomness is used to model the correlations in sequences containing various subsignals and noise. Kolmogorov stochasticity parameter enables to quantify the randomness in number sequences and hence appears as an…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 S. Sargsyan

Kolmogorov's statistic is used for the analysis of properties of perturbations in the Cosmic Microwave Background signal. We obtain the maps of the Kolmogorov stochasticity parameter for W and V band temperature data of WMAP which are…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-13 T. Ghahramanyan , S. Mirzoyan , E. Poghosian , G. Yegorian

The plane-mirror symmetry previously noticed in the Cosmic Microwave Background (CMB) temperature anisotropy maps of Wilkinson Microwave Anisotropy Probe is shown to possess certain anomalous properties. The degree of the randomness…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 V. G. Gurzadyan , T. Ghahramanyan , A. L. Kashin , H. G. Khachatryan , A. A. Kocharyan , H. Kuloghlian , D. Vetrugno , G. Yegorian

The problem of separation of different signals in the Cosmic Microwave Background (CMB) radiation using the difference in their statistics is analyzed. Considering samples of sequences which model the CMB as a superposition of signals, we…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 S. Mirzoyan , E. Poghosian

We develop a powerful analytical formalism for calculating the energy density of the stochastic gravitational wave background, including a full description of its anisotropies. This is completely general, and can be applied to any…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Alexander C. Jenkins , Mairi Sakellariadou

Despite the fact that the physics of the cosmic microwave background anisotropies is most naturally expressed in Fourier space, pixelised maps are almost always used in the analysis and simulation of microwave data. A complementary approach…

I report on recent developments in the theory of cosmic background radiation perturbations. I describe ways of modeling alternatives to the canonical Gaussian theories within the standard framework of cosmological perturbation theory. Some…

Astrophysics · Physics 2016-08-30 Pedro G. Ferreira

The Kolmogorov stochasticity parameter is shown to act as a tool to detect point sources in the cosmic microwave background (CMB) radiation temperature maps. Kolmogorov CMB map constructed for the WMAP's 7-year datasets reveals tiny…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 V. G. Gurzadyan , A. L. Kashin , H. G. Khachatryan , A. A. Kocharyan , E. Poghosian , D. Vetrugno , G. Yegorian

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 combine detections of anisotropy in the Cosmic Microwave Background radiation with observations of inhomogeneity in the large-scale distribution of galaxies to test the predictions of models of cosmological structure formation. This…

Astrophysics · Physics 2009-09-25 Eric Gawiser

In this article we focus on the astrophysical results and the related cosmological implications derived from recent microwave surveys, with emphasis to those coming from the Planck mission. We critically discuss the impact of systematics…

I develop a method for assessing the ability of an instrument, coupled with an observing strategy, to measure the angular power spectrum of the cosmic microwave background (CMB). It allows for efficient calculation of expected parameter…

Astrophysics · Physics 2009-10-28 Lloyd Knox

The Kolmogorov stochasticity parameter (KSP) is applied to quantify the degree of randomness (stochasticity) in the temperature maps of the Cosmic Microwave Background radiation maps. It is shown that, the KSP for the WMAP5 maps is about…

Astrophysics · Physics 2009-11-13 V. G. Gurzadyan , A. A. Kocharyan

The cosmic microwave background anisotropy is sensitive to the slope and amplitude of primordial energy density and gravitational wave fluctuations, the baryon density, the Hubble constant, the cosmological constant, the ionization history,…

We show that the anisotropies of the astrophysical stochastic gravitational wave background in the mHz band have a strong dependence on the modelling of galactic and sub-galactic physics. We explore a wide range of self-consistent…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Giulia Cusin , Irina Dvorkin , Cyril Pitrou , Jean-Philippe Uzan

The paper explores the use of various machine learning methods to search for heterogeneous or atypical structures on astronomical maps. The study was conducted on the maps of the cosmic microwave background radiation from the Planck mission…

Instrumentation and Methods for Astrophysics · Physics 2024-11-14 I. A. Karkin , A. A. Kirillov , E. P. Savelova

In this paper we develop the theory of clusterization of peaks in a Gaussian random field. We have obtained new mathematical results from this theory and the theory of percolation and have proposed a topological method of analysis of sky…

Astrophysics · Physics 2009-10-28 D. I. Novikov , H. E. Jorgensen

We introduce a simple yet powerful {\it analytic} method which obtains the structure of cosmic microwave background anisotropies to better than 5-10\% in temperature fluctuations on {\it all} scales. It is applicable to {\it any} model in…

Astrophysics · Physics 2009-07-17 Wayne Hu , Naoshi Sugiyama

We consider several factors concerning the design of observing strategies in Cosmic Microwave Background (CMB) anisotropy experiments. First we consider the number of independent points on the sky one should observe given a fixed observing…

Astrophysics · Physics 2007-05-23 R. K. Schaefer , L. Piccirillo
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