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We solve the wave equation for the electromagnetic field tensors associated with the CMBR photons in a universe with scalar metric perturbations. We show that the coupling of the electromagnetic fields with the curvature associated with the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Subhendra Mohanty , A. R. Prasanna

The emission in the hyperfine structure 21 cm line of atomic hydrogen arising in the halos with masses $\sim10^6-10^{10}$ M$_\odot$ from the Dark Ages in the models with Warm Dark Matter (WDM) is analysed. The halos are assumed to be formed…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-25 B. Novosyadlyj , V. Shulga , Yu. Kulinich , W. Han

We report a systematic rotation of the plane of polarization of electromagnetic radiation propagating over cosmological distances. The effect is extracted independently from Faraday rotation, and found to be correlated with the angular…

Astrophysics · Physics 2008-11-26 Borge Nodland , John P. Ralston

We discuss the large scale polarization of the cosmic microwave background induced by the anisotropy of the spatial geometry of our universe. Assuming an eccentricity at decoupling of about $0.64 10^{-2}$, we find an average large scale…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-18 Paolo Cea

Recently, Pang et al reported a novel polarization transfer scheme applicable to three-spin systems, whereby a rotating-frame NMR analogue of the cross effect could transfer polarization between; e.g., two 13Cs and an 15N in a single…

Quantum Physics · Physics 2026-04-21 Sundaresan Jayanthi , Adonis Lupulescu , Julia Grinshtein , Lucio Frydman

A particle, which moves in a crystal, experiences weak interactions with electrons and nuclei alongside with electromagnetic interaction. Measuring the polarization vector and the angular distribution of charged and neutral particles…

High Energy Physics - Phenomenology · Physics 2019-05-17 V. G. Baryshevsky

The change of the transverse spin asymmetry in the scattering of highly-relativistic spin-polarized electrons from nuclei by vacuum polarization effects is calculated within the Uehling approximation. Results are provided for 1 - 100 MeV…

Atomic Physics · Physics 2014-07-28 D. H. Jakubassa-Amundsen

A classical circularly polarized electromagnetic wave carries angular momentum, and represents the classical limit of a photon, which carries quantized spin. It is shown that a very similar picture of a circularly polarized coherent wave…

Quantum Physics · Physics 2007-05-23 Alan M. Kadin

The precise measurement of the sky-averaged HI absorption signal between 50 and 200 MHz is the primary goal of global 21-cm cosmology. This measurement has the potential to unravel the underlying physics of cosmic structure formation and…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-04 Emma Shen , Dominic Anstey , Marta Spinelli , Eloy de Lera Acedo , Anastasia Fialkov

We compute the polarized signal from atmospheric molecular oxygen due to Zeeman effect in the Earth magnetic field for various sites suitable for CMB measurements such as South Pole, Dome C (Antarctica) and Atacama desert (Chile). We…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-05 Giulio Fabbian , Sebastiano Spinelli , Massimo Gervasi , Andrea Tartari , Mario Zannoni

A primordial degree of circular polarization of the Cosmic Microwave Background is not observationally excluded. The hypothesis of primordial dichroism can be quantitatively falsified if the plasma is magnetized prior to photon decoupling…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Massimo Giovannini

Cosmic evolution in the hydrogen content of the Universe through recombination and up to the end of reionization is expected to be revealed as subtle spectral features in the uniform extragalactic cosmic radio background. The redshift…

Instrumentation and Methods for Astrophysics · Physics 2015-01-20 Ravi Subrahmanyan , N. Udaya Shankar , Jonathan Pritchard , Harish K. Vedantham

We calculate nuclear-polarization energy shifts for hydrogenlike $^{208}_{~82}$Pb$^{81+}$. A retarded transverse part as well as the Coulomb part is taken into account as the electromagnetic interaction between an electron and the nucleus.…

Nuclear Theory · Physics 2009-11-07 Akihiro Haga , Yataro Horikawa , Yasutoshi Tanaka

The 21\,cm transition of neutral hydrogen is opening an observational window into the cosmic dawn of the universe---the epoch of first star formation. We use 28\,hr of data from the Owens Valley Radio Observatory Long Wavelength Array…

We study the polarization characteristics of x-ray photons scattered by hydrogenic atoms, based on the Dirac equation and second-order perturbation theory. The relativistic states used in calculations are obtained using the finite basis set…

Atomic Physics · Physics 2014-10-23 Laleh Safari , Jose Paulo Santos , Pedro Amaro , Filippo Fratini

The global and local spin polarization measurements of $\Lambda$ ($\bar{\Lambda}$) hyperons by STAR and ALICE Collaborations open up an immense interest in investigating the spin polarization dynamics in heavy-ion collisions. Recent studies…

High Energy Physics - Phenomenology · Physics 2025-05-30 Bhagyarathi Sahoo , Captain R. Singh , Raghunath Sahoo

We compute the circularly polarized signal from atmospheric molecular oxygen. Polarization of O2 rotational lines is caused by Zeeman effect in the Earth magnetic field. We evaluate the circularly polarized emission for various sites…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Sebastiano Spinelli , Giulio Fabbian , Andrea Tartari , Mario Zannoni , Massimo Gervasi

The anomalous 21 cm absorption feature reported by EDGES has galvanized the study of scenarios in which dark matter (DM) siphons off thermal energy from the Standard Model (SM) gas. In a departure from the much-discussed models that achieve…

High Energy Physics - Phenomenology · Physics 2020-12-15 Lucas Johns , Seth Koren

We calculate the polarization of synchrotron radiation produced at the relativistic reconfinement shocks, taking into account globally ordered magnetic field components, in particular toroidal and helical fields. In these shocks, toroidal…

High Energy Astrophysical Phenomena · Physics 2012-07-02 Krzysztof Nalewajko , Marek Sikora
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