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Under the assumption that the concordance Lambda cold dark matter (CDM) model is the correct model, we test the cosmic microwave background (CMB) anisotropy data for systematic effects by examining the band pass temperature residuals with…

Astrophysics · Physics 2007-05-23 Louise M. Griffiths , Charles H. Lineweaver

Measurement of Cosmic Microwave Background (CMB) temperature by Planck has resulted in extremely tight constraints on the $\Lambda$CDM model. However the data indicates a evidence of dipole modulated temperature fluctuations at large…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-06 Suvodip Mukherjee

The study of the angular power spectrum of Cosmic Microwave Background (CMB) anisotropies, both in intensity and in polarisation, has led to the tightest constraints on cosmological parameters. However, this statistical quantity is not…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-08 Javier Carrón Duque , Alessandro Carones , Domenico Marinucci , Marina Migliaccio , Nicola Vittorio

We study the cosmic microwave background (CMB) anisotropy due to spherically symmetric nonlinear structures in flat universes with dust and a cosmological constant. By modeling a time-evolving spherical compensated void/lump by…

Astrophysics · Physics 2009-02-20 Nobuyuki Sakai , Kaiki Taro Inoue

Recent tentative findings of non-Gaussian structure in the COBE-DMR dataset have triggered renewed attention to candidate models from which such intrinsic signature could arise. In the framework of slow roll inflation with built-in non…

Astrophysics · Physics 2009-10-31 Alejandro Gangui , Jerome Martin

We study the possibility for constraining the topology of the Universe by means of the matched circles statistic applied to polarised cosmic microwave background (CMB) anisotropy maps. The advantages of using the CMB polarisation maps in…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-09 P. Bielewicz , A. J. Banday , K. M. Gorski

We present a simple, yet accurate approximation for calculating the cosmic microwave background anisotropy power spectrum in adiabatic models. It consists of solving for the evolution of a two-fluid model until the epoch of recombination…

Astrophysics · Physics 2009-10-22 Uros Seljak

In the first part of this work, I review the theoretical framework of cosmological perturbation theory necessary to understand the generation and evolution of cosmic microwave background (CMB) anisotropies. Using analytical and numerical…

Astrophysics · Physics 2009-09-29 Roberto Trotta

The Cosmic Microwave Background (CMB) bispectrum of the temperature anisotropies induced by a network of cosmic strings is derived for small angular scales, under the assumption that the principal cause of temperature fluctuations is the…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-06 Mark Hindmarsh , Christophe Ringeval , Teruaki Suyama

The properties of the Cosmic Microwave Background (CMB) maps carry valuable cosmological information. Here we report the results of the analysis hot and cold CMB anisotropy spots in the BOOMERanG 150 GHz map in terms of number, area,…

Accurate measurements of the cosmic microwave background (CMB) anisotropies with an angular resolution of a few arcminutes can be used to determine fundamental cosmological parameters such as the densities of baryons, cold and hot dark…

Astrophysics · Physics 2016-01-13 J. Richard Bond , George Efstathiou , Max Tegmark

We investigate parity-violating signatures of temperature and polarization bispectra of the cosmic microwave background (CMB) in an inflationary model where a rolling pseudoscalar produces large equilateral tensor non-Gaussianity. By a…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-22 Maresuke Shiraishi , Angelo Ricciardone , Shohei Saga

A major problem in Cosmic Microwave Background (CMB) anisotropy mapping, especially in a total-power mode, is the presence of low-frequency noise in the data streams. If unproperly processed, such low-frequency noise leads to striping in…

Astrophysics · Physics 2009-10-31 B. Revenu , A. Kim , R. Ansari , F. Couchot , J. Delabrouille , J. Kaplan

We calculate the cosmic microwave background (CMB) angular trispectrum, spherical harmonic transform of the four-point correlation function, from primordial non-Gaussianity in primordial curvature perturbations characterized by a constant…

Astrophysics · Physics 2009-11-11 Noriyuki Kogo , Eiichiro Komatsu

We develop an efficient method based on the linear regression algorithm to probe the cosmological CPT violation using the CMB polarisation data. We validate this method using simulated CMB data and apply it to recent CMB observations. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-06 Gong-Bo Zhao , Yuting Wang , Jun-Qing Xia , Mingzhe Li , Xinmin Zhang

We present a new and especially powerful signature of cosmic strings and other topological or non-topological defects in the polarization of the cosmic microwave background (CMB). We show that even if defects contribute 1% or less in the…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Juan Garcia-Bellido , Ruth Durrer , Elisa Fenu , Daniel G. Figueroa , Martin Kunz

Most of the cosmological information extracted from the CMB has been obtained through the power spectrum, however there is much more to be learnt from the statistical distribution of the temperature random field. We review some recent…

Astrophysics · Physics 2015-06-24 Enrique Martinez-Gonzalez

We present a new, model-independent approach for measuring non-Gaussianity of the Cosmic Microwave Background (CMB) anisotropy pattern. Our approach is based on the empirical distribution function of the normalized spherical harmonic…

Astrophysics · Physics 2011-05-10 Frode K. Hansen , Domenico Marinucci , Paolo Natoli , Nicola Vittorio

In this lecture, after a synthetic review of measurements of CMB temperature anisotropies and of their cosmological implications, the theoretical background of CMB polarization is summarized and the concepts of the main experiments that are…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-14 Gianfranco De Zotti

Cosmic microwave background (CMB) anisotropy may result from both scalar and tensor perturbations. For a sufficiently narrow range of angular scales, CMB perturbations can be characterized by four parameters. Results from the Cosmic…

Astrophysics · Physics 2009-10-22 Scott Dodelson , Lloyd Knox , Edward W. Kolb
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