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We search for the presence of cosmological neutrino background (CNB) anisotropies in recent WMAP 5-year data using their signature imprinted on modifications to cosmic microwave background (CMB) anisotropy power spectrum. By parametrizing…

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. The relative…

High Energy Astrophysical Phenomena · Physics 2015-10-16 The HAWC Collaboration , The IceCube Collaboration

A conventional explanation of the dipole anisotropy of the cosmic microwave background (CMB) radiation is in terms of the Doppler effect: our galaxy is moving with respect to CMB frame with $ \sim 600 ~ km ~ s^{-1} $. However, as the deep…

Astrophysics · Physics 2007-05-23 M. Jaroszynski , B. Paczynski

The Wilkinson Microwave Anisotropy Probe WMAP has mapped the entire sky in five frequency bands between 23 and 94 GHz with polarization sensitive radiometers. We present three-year full-sky maps of the polarization and analyze them for…

We consider the issue of hemispherical power asymmetry in the three-year WMAP data, adopting a previously introduced modulation framework. Computing both frequentist probabilities and Bayesian evidences, we find that the model consisiting…

Astrophysics · Physics 2009-11-13 H. K. Eriksen , A. J. Banday , K. M. Gorski , F. K. Hansen , P. B. Lilje

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

We have used the Berkeley-Illinois-Maryland-Association (BIMA) array outfitted with sensitive cm-wave receivers to expand our search for arcminute scale anisotropy of the Cosmic Microwave Background (CMB). The interferometer was placed in a…

Astrophysics · Physics 2009-10-31 K. S. Dawson , W. L Holzapfel , J. E. Carlstrom , M. Joy , S. J. LaRoque , E. D. Reese

The Microwave Anisotropy Probe and Planck missions will provide low noise maps of the temperature of the cosmic microwave background (CMB). These maps will allow measurement of the power spectrum of the CMB with measurement noise below…

The cosmic microwave background radiation provides unique constraints on cosmological models. In this Letter we present a summary of the spatial properties of the cosmic microwave background radiation based on the full 4 years of COBE DMR…

Observations of the Cosmic Microwave background have provided many of the most powerful constraints we have on cosmology and events in the early universe. The spectrum and isotropy of CBR have long been a pillar of Big Bang models. The…

Astrophysics · Physics 2016-08-30 George F. Smoot

We investigate the hemispherical power asymmetry in the cosmic microwave background on small angular scales. We find an anomalously high asymmetry in the multipole range l=601-2048, with a naive statistical significance of 6.5 sigma.…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-30 Samuel Flender , Shaun Hotchkiss

The Cosmic Microwave Background Radiation (CMB) is an invaluable probe of the conditions of the early universe. Recent measurements of its spatial anisotropy have allowed accurate determinations of several fundamental cosmological…

Astrophysics · Physics 2009-09-29 Christopher O'Dell

A ground-based polarimeter, PIQUE, operating at 90 GHz has set a new limit on the magnitude of any polarized anisotropy in the cosmic microwave background. The combination of the scan strategy and full width half maximum beam of 0.235…

Astrophysics · Physics 2009-10-31 M. M. Hedman , D. Barkats , J. O. Gundersen , S. T. Staggs , B. Winstein

We have simulated cosmic microwave background (CMB) anisotropy maps for several COBE-DMR-normalized cold dark matter (CDM) cosmogonies, to make predictions for the upcoming MAP experiment. We have studied the sensitivity of the simulated…

We reexamine the evidence of the hemispherical power asymmetry, detected in the CMB WMAP data using a new method. At first, we analyze the hemispherical variance ratios and compare these with simulated distributions. Secondly, working…

Astrophysics · Physics 2014-11-18 Bartosz Lew

This document describes the Millimeter Anisotropy eXperiment IMaging Array (MAXIMA), a balloon-borne experiment measuring the temperature anisotropy of the Cosmic Microwave Background (CMB) on angular scales of 10 arcminutes to 5 degrees.…

Astrophysics · Physics 2011-11-09 Bahman Rabii

We present the angular power spectrum derived from the first-year Wilkinson Microwave Anisotropy Probe (WMAP) sky maps. We study a variety of power spectrum estimation methods and data combinations and demonstrate that the results are…

The Standard Inflationary model predicts an isotropic distribution of the Cosmic Microwave Background temperature fluctuations. Detection of deviations from statistical isotropy would call for a revision of the physics of the early…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Laura Cayon

We consider an inhomogeneous model and independently an anisotropic model of primordial power spectrum in order to describe the observed hemispherical anisotropy in Cosmic Microwave Background Radiation. This anisotropy can be parametrized…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-31 Rahul Kothari , Shamik Ghosh , Pranati K. Rath , Gopal Kashyap , Pankaj Jain

The primary goal of the MAP satellite, now in orbit, is to make high fidelity polarization sensitive maps of the full sky in five frequency bands between 20 and 100 GHz. From these maps we will characterize the properties of the cosmic…