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arXiv · 1406.6213

Photon-neutrino scattering and the B-mode spectrum of CMB photons

Jafar Khodagholizadeh·Rohoollah Mohammadi·She-Sheng Xue
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Abstract

On the basis of the quantum Boltzmann equation governing the time-evolution of the density matrix of polarized CMB photons in the primordial scalar perturbations of metric, we calculate the B-mode spectrum of polarized CMB photons contributed from the scattering of CMB photons and CNB neutrinos (Cosmic Neutrino Background). We show that such contribution to the B-mode spectrum is negligible for small $\ell$, however is significantly large for $50 < \ell< 200$ by plotting our results together with the BICEP2 data. Our study and results imply that in order to theoretically better understand the origin of the observed B-mode spectrum of polarized CMB photons ($r$-parameter), it should be necessary to study the relevant and dominate processes in both tensor and scalar perturbations.

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Jafar Khodagholizadeh, Rohoollah Mohammadi, She-Sheng Xue. 2014-06-24. Photon-neutrino scattering and the B-mode spectrum of CMB photons. https://doi.org/10.1103/physrevd.90.091301

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