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The V-mode polarization of the Cosmic Microwave Background is discussed in a weakly magnetized plasma. The VV and VT angular power spectra are computed for adiabatic initial conditions of the Einstein-Boltzmann hierarchy. Depending upon the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Massimo Giovannini

The standard cosmological model, which includes only Compton scattering photon interactions at energy scales near recombination, results in zero primordial circular polarization of the cosmic microwave background. In this paper we consider…

Astrophysics · Physics 2009-11-13 Stephon Alexander , Joseph Ochoa , Arthur Kosowsky

A theoretical study of spin dynamics in non-relativistic particle beams with interacting angular momenta traversing static, spatially varying magnetic fields is presented. The computational framework evaluates sinusoidal magnetic field…

The redshifted 21-cm line of distant neutral H atoms provides a probe of the cosmic ``dark ages'' and the epoch of reionization (``EOR'') which ended them. The radio continuum produced by this redshifted line can be seen in absorption or…

Astrophysics · Physics 2009-11-13 Paul R. Shapiro , Ilian T. Iliev , Garrelt Mellema , Ue-Li Pen , Hugh Merz

In addition to its spectrum and temperature anisotropy, the 2.7K Cosmic Microwave Background is also expected to exhibit a low level of polarization. The spatial power spectrum of the polarization can provide details about the formation of…

Astrophysics · Physics 2009-10-30 Brian Keating , Peter Timbie , Alexander Polnarev , Julia Steinberger

Electron scattering induces a polarization in the cosmic microwave background (CMB) signal measured in the direction of a galaxy cluster due to the presence of a quadrupole component in the CMB temperature distribution. Measuring the…

Astrophysics · Physics 2009-10-31 S. Y. Sazonov , R. A. Sunyaev

We calculate the secondary anisotropies in the CMB produced by inhomogeneous reionization from simulations in which the effects of radiative and stellar feedback effects on galaxy formation have been included. This allows to…

Astrophysics · Physics 2009-10-31 M. Bruscoli , A. Ferrara , R. Fabbri , B. Ciardi

The configuration of the regular magnetic field in M31 is deduced from radio polarization observations at the wavelengths 6, 11 and 20 cm. By fitting the observed azimuthal distribution of polarization angles, we find that the regular…

Astrophysics · Physics 2009-11-10 A. Fletcher , E. M. Berkhuijsen , R. Beck , A. Shukurov

Tangled, primordial cosmic magnetic fields create small rotational velocity perturbations on the last scattering surface (LSS) of the cosmic microwave background radiation (CMBR). For fields which redshift to a present value of $B_0 =…

Astrophysics · Physics 2009-10-31 T. R. Seshadri , Kandaswamy Subramanian

With the advent of the first luminous sources at Cosmic Dawn (CD), the redshifted 21-cm signal, from the neutral hydrogen in the Inter-Galactic Medium (IGM), is predicted to undergo a transition from absorption to emission against the CMB.…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-04 Mohd Kamran , Suman Majumdar , Raghunath Ghara , Garrelt Mellema , Somnath Bharadwaj , Jonathan R. Pritchard , Rajesh Mondal , Ilian T. Iliev

We compute numerically the scalar- and tensor-mode induced Stokes parameters of the cosmic microwave background, by taking into account the basis rotation effects. It is found that the tensor contribution to the polarization power spectrum…

Astrophysics · Physics 2009-10-28 Ka Lok Ng , Kin-Wang Ng

It should be possible to generate multi-ampere spin-polarized beams of hydrogen isotopes by repeated charge-transfer collisions in highly spin-polarized Cs vapor. Estimates suggest that off-resonant Raman pumping with kW scale narrowband…

Atomic Physics · Physics 2026-05-19 Thad G. Walker , Cary B. Forest , Deniz D. Yavuz

We measure several properties of the reionization process and the corresponding low-frequency 21-cm signal associated with the neutral hydrogen distribution, using a large volume, high resolution simulation of cosmic reionization. The…

The 21-cm signal of neutral hydrogen is a sensitive probe of the Epoch of Reionization (EoR) and Cosmic Dawn. Currently operating radio telescopes have ushered in a data-driven era of 21-cm cosmology, providing the first constraints on the…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-10 Aviad Cohen , Anastasia Fialkov , Rennan Barkana , Raul Monsalve

Circular polarization of the cosmic microwave background (CMB) can be induced by Faraday conversion of the primordial linearly polarized radiation as it propagates through a birefringent medium. Recent work has shown that the dominant…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-13 Keisuke Inomata , Marc Kamionkowski

We study contributions from inhomogeneous (patchy) reionization to arcminute scale ($1000 < \ell < 10,000$) cosmic microwave background (CMB) anisotropies. We show that inhomogeneities in the ionization fraction, rather than in the mean…

Astrophysics · Physics 2008-11-26 M. G. Santos , A. Cooray , Z. Haiman , L. Knox , C. -P. Ma

A new spin wavelet transform on the sphere is proposed to analyse the polarisation of the cosmic microwave background (CMB), a spin $\pm 2$ signal observed on the celestial sphere. The scalar directional scale-discretised wavelet transform…

Instrumentation and Methods for Astrophysics · Physics 2014-12-04 Jason D. McEwen , Martin Büttner , Boris Leistedt , Hiranya V. Peiris , Pierre Vandergheynst , Yves Wiaux

We will show that isotropic collisions of electrons and protons with neutral hydrogen can lead to creation of net orientation of the atomic levels in the presence of a magnetic field. Consequently, the emitted Stokes-V profile of the…

Astrophysics · Physics 2008-12-01 Jiri Stepan , Sylvie Sahal-Brechot

We examine the polarization signal of the cosmic microwave background radiation associated with distant clusters. The polarization is induced by the Thomson scattering of microwave photons with ionized gas of clusters and contains…

Astrophysics · Physics 2016-08-30 Naoki Seto , Misao Sasaki

Polarimetry of the Cosmic Microwave Background (CMB) represents one of the possible diagnostics aimed at testing large-scale magnetism at the epoch of the photon decoupling. The propagation of electromagnetic disturbances in a magnetized…

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