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We present results from the QMAP balloon experiment, which maps the Cosmic Microwave Background (CMB) and probes its angular power spectrum on degree scales. In two separate flights, data were taken in six channels at two frequency bands…

With polarization of the cosmic microwave background (CMB) now detected, and confirmed by several independent experiments, the next goal is to characterise accurately its statistical properties. In these lecture notes we review the physical…

Astrophysics · Physics 2018-05-02 Anthony Challinor

We present a new blind formulation of the Cosmic Microwave Background (CMB) inference problem. The approach relies on a phenomenological model of the multi-frequency microwave sky without the need for physical models of the individual…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-30 Flavien Vansyngel , Benjamin D. Wandelt , Jean-François Cardoso , Karim Benabed

Most cosmic microwave background experiments observe the sky along circular or near-circular scans on the celestial sphere. For such experiments, we show that simple linear systems connect the Fourier spectra of temperature and polarization…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-25 Jia-Rui Li , Chunlong Li , Jie Jiang , Yi-Fu Cai , Jacques Delabrouille , Deliang Wu , Hong Li

We study the large-scale angular correlation signatures of the Cosmic Microwave Background (CMB) temperature fluctuations from WMAP data in several spherical cap regions of the celestial sphere, outside the Kp0 or Kp2 cut-sky masks. We…

Spectral distortions of the Cosmic Microwave Background (CMB) offer the possibility of probing processes which occurred during the evolution of our Universe going back up to Z$\simeq 10^7$. Unfortunately all the attempts so far carried out…

Instrumentation and Methods for Astrophysics · Physics 2017-02-22 Giorgio Sironi

Following Kamionkowski (2008), a quadratic estimator of the rotation of the plane of polarization of the CMB is constructed. This statistic can estimate a spatially varying rotation angle. We use this estimator to quantify the prospects of…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-03 Amit P. S. Yadav , Rahul Biswas , Meng Su , Matias Zaldarriaga

In this paper, we investigate the effects of helical primordial magnetic fields (PMFs) on the cosmic microwave background (CMB) reduced bispectrum. We derive the full three-point statistics of helical magnetic fields and numerically…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-13 Hector J. Hortua , Leonardo Castañeda

A complete numerical calculation of the temperature anisotropies and the polarization of the cosmic microwave background (CMB) is presented for a non zero cross correlation of a stochastic magnetic field with the primordial curvature…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-15 Kerstin E. Kunze

I review the general aspects of cosmological parameter estimation from observations of the cosmic microwave background (CMB) temperature anisotropies in the framework of inflationary adiabatic models. The most recent CMB datasets are…

Astrophysics · Physics 2009-10-31 A. Balbi

Searching for the signal of primordial gravitational waves in the B-modes (BB) power spectrum is one of the key scientific aims of the cosmic microwave background (CMB) polarization experiments. However, this could be easily contaminated by…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-18 Si-Yu Li , Jun-Qing Xia , Mingzhe Li , Hong Li , Xinmin Zhang

The natural approach to a spectral analysis of data distributed on the sky employs spherical harmonic decomposition. A common problem encountered in practical astronomy is the lack of full sky coverage in the available data. For example,…

Astrophysics · Physics 2009-10-22 Krzysztof M. Gorski

We have studied the cosmic microwave background (CMB) map looking for features beyond cosmological isotropy. We began by tiling the CMB variance map (which are produced by different smoothing scales) with stripes of different sizes along…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-12 MohammadHossein Jamshidi , Abdolali Banihashemi , Nima Khosravi

The anisotropies of the cosmic microwave background (CMB) are computed for the half-turn space E_2 which represents a compact flat model of the Universe, i.e. one with finite volume. This model is inhomogeneous in the sense that the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 R. Aurich , S. Lustig

Primordial magnetic fields lead to non-Gaussian signals in the Cosmic Microwave Background (CMB) even at the lowest order, as magnetic stresses, and the temperature anisotropy they induce, depend quadratically on the magnetic field. In…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-03 T. R. Seshadri , Kandaswamy Subramanian

Certain modified gravity theories predict the existence of an additional, non-conformally coupled scalar field. A disformal coupling of the field to the Cosmic Microwave Background (CMB) is shown to affect the evolution of the energy…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Carsten van de Bruck , Jack Morrice , Susan Vu

The weak lensing effect on the cosmic microwave background (CMB) induces distortions in spatial pattern of CMB anisotropies, and statistical properties of CMB anisotropies become a weakly non-Gaussian field. We first summarize the weak…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-17 Toshiya Namikawa

Large-scale magnetic fields affect the scalar modes of the geometry whose ultimate effect is to determine the anisotropies of the Cosmic Microwave Background (CMB in what follows). For the first time, a consistent numerical approach to the…

Astrophysics · Physics 2010-04-29 Massimo Giovannini , Kerstin E. Kunze

The recent Planck data on the power spectrum of temperature anisotropies of the cosmic microwave background marginally support deviations from the $\Lambda$CDM model at several multipoles. With a view towards current and forthcoming…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-27 Spyros Sypsas

Suggestions have been made that the microwave background observed by COBE and WMAP and dubbed Cosmic Microwave Background (CMB) may have an origin within our own Galaxy or Earth. To consider the signal that may be correlated with Earth, a…

Astrophysics · Physics 2007-05-23 Ria Follop , Anais Rassat , Asantha Cooray , Filipe B. Abdalla
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