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Related papers: Angular Power Spectra with Finite Counts

200 papers

We present the first targeted measurement of the power spectrum of anisotropies of the radio synchrotron background, at 140 MHz where it is the overwhelmingly dominant photon background. This measurement is important for understanding the…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-06 A. R. Offringa , J. Singal , S. Heston , S. Horiuchi , D. M. Lucero

The origin of power asymmetry and other measures of statistical anisotropy on the largest scales of the universe, as manifested in Cosmic Microwave Background (CMB) and large-scale structure data, is a long-standing open question in…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-12 Pablo Fosalba , Enrique Gaztanaga

Precision measurements of anisotropies in the cosmic microwave background and of the clustering of large-scale structure have supposedly confirmed that the primordial density perturbation has a (nearly) scale-invariant spectrum. However…

High Energy Physics - Phenomenology · Physics 2011-02-16 Subir Sarkar

Cosmic microwave background observations are most commonly analyzed by estimating the power spectrum. In the limit where the CMB statistics are perfectly Gaussian, this extracts all the information, but the CMB also contains detectable…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-09 Kendrick M. Smith

Polarization induced by cosmological scalar perturbations leads to a typical anisotropy pattern, which can best be analyzed in Fourier domain. This allows one to unambiguously distinguish cosmological signal of polarization from other…

Astrophysics · Physics 2009-10-28 Uros Seljak

Extracting the three dimensional power spectrum from the 2D distribution of galaxies has become a standard tool of cosmology. This extraction requires some assumptions about the scaling of the power spectrum with redshift; all treatments to…

Astrophysics · Physics 2007-05-23 R. Scranton , S. Dodelson

The genuine quantum gravity effects can already be around us. It is likely that the observed large-angular-scale anisotropies in the microwave background radiation are induced by cosmological perturbations of quantum-mechanical origin. Such…

General Relativity and Quantum Cosmology · Physics 2007-05-23 L. P. Grishchuk

Statistical isotropy is often assumed in cosmology and should be tested rigorously against observational data. We construct simple quadratic estimators to reconstruct asymmetry in the primordial power spectrum from CMB temperature and…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-16 Yin-Zhe Ma , George Efstathiou , Anthony Challinor

We develop a method for estimating the shear power spectra from weak lensing observations and test it on simulated data. Our method describes the shear field in terms of angular power spectra and cross correlation of the two shear modes…

Astrophysics · Physics 2008-11-26 Wayne Hu , Martin White

Second-order power spectra of Cosmic Microwave Background (CMB) anisotropies due to random primordial perturbations at the matter dominant stage are studied, based on the relativistic second-order theory of perturbations in flat…

Astrophysics · Physics 2008-11-26 Kenji Tomita

We predict that neutrino sources following the matter distribution of the universe result in an anisotropy in the neutrino sky imprinted by the local large-scale structure. We calculate the level of this anisotropy and explore how it…

High Energy Astrophysical Phenomena · Physics 2025-11-13 Marco Stein Muzio , Noémie Globus

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…

In the last decade, a number of experiments dealt with the problem of measuring the arrival direction distribution of cosmic rays, looking for information on the propagation mechanisms and the identification of their sources. Any deviation…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Roberto Iuppa , Giuseppe Di Sciascio

The marked power spectrum - a two-point correlation function of a transformed density field - has emerged as a promising tool for extracting cosmological information from the large-scale structure of the Universe. In this work, we present…

We present a maximum-likelihood analysis for estimating the angular distribution of power in an anisotropic stochastic gravitational-wave background using ground-based laser interferometers. The standard isotropic and gravitational-wave…

Instrumentation and Methods for Astrophysics · Physics 2013-09-05 Eric Thrane , Stefan Ballmer , Joseph D. Romano , Sanjit Mitra , Dipongkar Talukder , Sukanta Bose , Vuk Mandic

A model-independent determination of the primordial power spectrum of matter density fluctuations could uniquely probe physics of the very early universe, and provide powerful constraints on inflationary models. We parametrize the…

Astrophysics · Physics 2009-10-31 Yun Wang , Grant J. Mathews

The theoretical basis for the prediction of anisotropies in the cosmic microwave background is very well developed. Very low amplitude density and temperature perturbations produce small gravitational effects, leading to an anisotropy that…

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

We analyze observations of the microwave sky made with the Python experiment in its fifth year of operation at the Amundsen-Scott South Pole Station in Antarctica. After modeling the noise and constructing a map, we extract the cosmic…

Astrophysics · Physics 2009-11-07 K. Coble , S. Dodelson , M. Dragovan , K. Ganga , L. Knox , J. Kovac , B. Ratra , T. Souradeep

Several early Universe scenarios predict a direction-dependent spectrum of primordial curvature perturbations. This translates into the violation of the statistical isotropy of cosmic microwave background radiation. Previous searches for…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 S. Ramazanov , G. Rubtsov , M. Thorsrud , F. R. Urban

The angular power spectrum of the Cosmic Microwave Background has been measured out to sufficiently small angular scale to encompass a few acoustic oscillations. We use a phenomenological fit to the angular power spectrum to quantify the…

Astrophysics · Physics 2009-11-07 M. Douspis , P. G. Ferreira